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A person in the first stages of multiple sclerosis may have trouble gripping objects or experience dizziness, fatigue, and vision problems. Symptoms may get progressively worse. Image Credit: © Minerva Studio/Shutterstock

Epstein-Barr infection found to increase risk of multiple sclerosis

Multiple sclerosis (MS) is an incurable autoimmune disease that afflicts 2.8 million people worldwide. People diagnosed with MS experience progressive damage to their central nervous system and can lose about seven years of their life expectancy, according to the National Multiple Sclerosis Society. Now, using data from more than 10 million U.S. military recruits monitored over a 20-year period, researchers at the Harvard T.H. Chan School of Public Health determined that the biggest risk factor for contracting the disease may be previous infection with the Epstein-Barr virus (EBV). The team published its findings on January 13 in the journal <a href="https://www.science.org/doi/10.1126/science.abj8222">Science</a>.
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While there are nearly 1,000 genetic precursors for MS, including sex, “no risk factor stands out like Epstein-Barr infections,” epidemiologist and Principal Investigator of the study Alberto Ascherio <a href="https://www.nytimes.com/2022/01/13/health/multiple-sclerosis-epstein-barr-virus.html">told The New York Times.</a> In fact, nearly every case of MS observed by Ascherio and his team was preceded by infection with EBV, a common strain of herpes spread through saliva and other bodily fluids. Of the 10 million military personnel involved in the study, 955 were diagnosed with MS during their service. Risk of MS increased 32-fold after infection with EBV, researchers found, a correlation not seen with any other viruses that the subjects contracted during their service. Additionally, other clinical biomarkers of MS increased only after EBV antibodies were detected in the patients' blood.Researchers say the findings suggest that EBV is the leading contributor to the development of MS. But how EBV leads to MS remains “unknown and elusive,” two Stanford University immunologists who were not involved in the study told <a href="https://www.scientificamerican.com/article/epstein-barr-virus-found-to-trigger-multiple-sclerosis/">Scientific American</a>.<a href="https://www.cdc.gov/epstein-barr/about-ebv.html">According to the CDC</a>, most people will be infected with EBV at some point in their lives. The virus also causes mononucleosis, commonly called “mono,” which more than 3 million people fall ill with every year in the U.S. Initial EBV infections cause few symptoms, but once EBV gets into the body’s immune cells, “it lurks in them permanently,” Michael Le Page <a href="https://www.newscientist.com/article/2304340-strongest-evidence-yet-that-ms-is-caused-by-epstein-barr-virus/">writes for New Scientist.</a>But contracting EBV will not necessarily lead someone to develop MS, the study authors caution. “Most people infected with this common virus do not develop multiple sclerosis,” the team reports in its paper. Still, like many other common viruses, EBV’s potential to wreak havoc on the body through reactivation is cause for investigation. There is currently no vaccine for EBV. Its status as a "non life-threatening" illness has led to a “lack of investment” in creating a vaccine, Michael Wilson, a neurologist at the University of California San Francisco <a href="https://www.statnews.com/2022/01/13/strong-new-evidence-suggests-virus-triggers-multiple-sclerosis/">told STAT News</a>. A preventative vaccine against EBV—much like the one launched for human papillomavirus (HPV), a common virus that in rare cases can cause cancer—may reduce the incidence of MS. “Studies like this suggest we should be pushing harder on developing a vaccine against EBV,” Wilson told STAT News.
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MS is diagnosed with an MRI of a person’s brain, usually between the ages of 20 and 50. In MS patients, a brain scan reveals small lesions, which are dead networks of thousands or millions of neurons. People who develop MS tend to have overactive immune systems, Gina Kolata writes for The New York Times. Patients may report “never getting a cold,” because their immune systems so quickly fight off viruses. Neurons are insulated by myelin sheaths, which not only protect the cells but also facilitate communication from the brain to the rest of the body. In MS patients, the immune system eats away at these myelin sheaths. Without the ability to send messages from the brain to the body, a person in the first stages of MS may have trouble gripping objects or experience dizziness, fatigue, and vision problems. As a patient’s immune system continues to attack their myelin sheaths, their symptoms may get progressively worse.  “But what triggers the immune system to turn on itself,” Megan Molteni writes for STAT News, “is still a mystery.” The connection between EBV and MS is helping demystify some of the questions around the debilitating chronic disease and accelerating vaccine development. Both Moderna, one of the first companies to produce an mRNA COVID-19 vaccine, and the National Institute of Allergy and Infectious Diseases are looking into manufacturing an EBV vaccine. This month, Moderna launched its first phase trial for an mRNA vaccine against EBV. If successful, Lydia Denworth reports for Scientific American, the vaccines could reduce the incidence of mono, some EBV-associated cancers, and potentially MS. 
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The underlying cause of multiple sclerosis is not yet known, but Epstein-Barr virus is a possible culprit, Harvard researchers say.

An artist's concept of a near-Earth asteroid like 2022 EB5. Image Credit: NASA/JPL-Caltech

Astronomers successfully predict an asteroid impact above Iceland

On Friday, Mar. 11 at around 7:30 p.m. GMT, an astronomer spotted an asteroid hurtling toward our planet at an estimated speed of 39,600 mph. By 9:30 p.m., the asteroid, dubbed “2022 EB5,” entered Earth’s atmosphere. It disintegrated over Jan Mayen island near Iceland, its pieces most likely plunging into the Arctic Ocean, the International Meteor Organization <a href="https://www.imo.net/2022-eb5-5th-predicted-earth-impactor-asteroid-on-march-11/">reports</a>. 2022 EB5’s descent marks the fifth time astronomers successfully mapped out an asteroid’s collision course with Earth ahead of impact.
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Krisztián Sárneczky, the astronomer who first spotted 2022 EB5, was at Konkoly Observatory’s Piszkéstető Mountain Station near Budapest, Hungary when he made the observation. Soon after reporting his finding of a mysterious object hurtling toward Earth to the International Astronomical Union's Minor Planet Center, fellow astronomers identified it as a near-Earth asteroid. “The sighting soon got a lot more interesting,” Chelsea Gohd <a href="https://www.space.com/asteroid-discovered-hours-before-earth-atmosphere-impact">writes for Space.com</a>. “​​Just 30 minutes after the discovery, data showed that the space rock was a mere two hours away from colliding with Earth's atmosphere.”2022 EB5 belongs to the Apollo asteroids, space rocks considered by NASA to be “potentially hazardous” because of the close approaches they make to Earth. Named for 1862 Apollo, an asteroid discovered by German astronomer Karl Reinmuth 90 years ago, it takes Apollo asteroids less than two years to orbit the Sun. Asteroid 2022 EB5, which astronomers believe was 10 feet wide prior to its descent to Earth (or as some news outlets say, “<a href="https://www.sciencetimes.com/articles/36593/20220314/asteroid-half-size-giraffe-hits-iceland-2-hours-astronomers-spotted.htm">half the size of a giraffe</a>”) quickly caught headlines and the attention of social media users on <a href="https://www.reddit.com/r/worldnews/comments/te89dm/asteroid_half_the_size_of_a_giraffe_strikes_earth/">platforms like Reddit</a>.
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<figcaption>NASA scientists predicted asteroid 2022 EB5's trajectory before hitting the Earth’s atmosphere on Mar. 11, 2022. The asteroid—estimated to be about 6.5 feet wide—was discovered only two hours before impact. Credit: NASA/JPL-Caltech
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Shortly after Sárneczky’s observation and report, NASA's "Near-Earth Asteroid Scout" (NEA Scout), “a miniaturized spacecraft known as a CubeSat,” <a href="https://www.nasa.gov/content/nea-scout">NASA writes</a>, began calculating 2022 EB5’s trajectory toward our planet. "As soon as Scout determined that 2022 EB5 was going to hit Earth's atmosphere," NASA's <a href="https://www.jpl.nasa.gov/news/nasa-system-predicts-impact-of-small-asteroid">Jet Propulsion Laboratory (JPL) reports</a>, NEA Scout alerted NASA's Center for Near Earth Objects (CNEOS) and its Planetary Defense Coordination Office, which is managing a new asteroid-deflection mission called <a href="https://www.youtube.com/watch?v=nGwnl7K5IWc">DART</a>. After only 40 minutes, NEA Scout and its team of scientists were able to predict 2022 EB5's exact impact time and location.
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Asteroids like 2022 EB5 are not big enough to be a hazard to our planet or society, researchers believe. Though 2022 EB5 likely “started out about 10 feet wide,” Kelly Kizer Whitt writes for <a href="https://earthsky.org/space/asteroid-discovered-hours-before-earth-impact-eb5/">EarthSky,</a> 2022 EB5 sizzled during its descent to about 6.5 feet according to NASA estimates, "much smaller than the objects that the Planetary Defense Coordination Office is tasked by NASA with detecting and warning about," NASA JPL reports. In fact, tiny asteroids "impact the atmosphere quite frequently," <a href="https://www.jpl.nasa.gov/news/nasa-system-predicts-impact-of-small-asteroid">CNEOS Director Paul Chodas</a> told NASA JPL. But unlike 2022 EB5, “very few of these asteroids have actually been detected in space and observed extensively prior to impact," Chodas said.In fact, “this is probably a once in a lifetime experience for an ‘asteroid hunter,’” Sárneczky told Space.com.2022 EB5's fiery plummet to the Earth may have caused a brilliant, visible shooting star, astronomers believe, but no citizen observations have been reported. While the remnants of some other Earth-striking asteroids have been recovered, "all of 2022 EB5 almost certainly burned up or fell into the Arctic Ocean," Eric Mack writes for <a href="https://www.forbes.com/sites/ericmack/2022/03/13/astronomer-spotted-an-asteroid-just-hours-before-it-impacted-earth/?sh=2f30ff9558fc">Forbes</a>, so it’s unlikely humans will recover pieces of the asteroid. Still, 2022 EB5 now joins an exclusive cosmic club of asteroids—2008 TC3, 2014 AA, 2018 LA, and 2019 MO—each named for their year of impact and whose collision courses with Earth were discovered before they came in contact with our atmosphere.
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Two hours before asteroid 2022 EB5 entered Earth’s atmosphere, scientists knew exactly when and where the space rock would strike.

The second-ever direct image of a black hole features Sagittarius A*, the supermassive black hole at the center of our galaxy. Image Credit: Event Horizon Telescope collaboration

Scientists capture first-ever image of our galaxy’s supermassive black hole

On Thursday morning, an international team of astrophysicists and other researchers released the world’s first image of the supermassive black hole at the center of our galaxy, 27,000 light-years from Earth. The event marks “the dawn of a new era of black hole physics,” the team<a href="https://twitter.com/ehtelescope/status/1524737908892049408"> announced on Twitter</a>.More than 4 million times the mass of our sun, the black hole, named Sagittarius A* (or Sgr A*, pronounced “sadge ay star,” for short) is so dense and massive that no light can escape its gravity. The visible light in the new image comes from bright stars, gas, and other space matter swarming around the black hole itself.
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The image is the first visual evidence of Sgr A*’s existence; the black hole was previously only indirectly confirmed by observations of stars in orbit around it. The image comes from the Event Horizon Telescope’s (EHT) international consortium. A group of more than 300 scientists helped with the effort to capture it, “compiling information from radio observatories around the world,” Bill Chappell <a href="https://www.npr.org/2022/05/12/1098472567/image-black-hole-milky-way">reports for NPR</a>. (The EHT, named for the event horizon, or “point of no return” from a black hole, consists of eight radio telescopes scattered across the globe.)In 2019, the EHT team compiled an <a href="https://www.pbs.org/wgbh/nova/article/first-black-hole-image/">image of Pōwehi</a>, a supermassive black hole 55 million light-years away in the galaxy Messier 87. Similar in appearance to Sgr A* but much more massive, Pōwehi is 6.5 billion times the mass of our sun.The much smaller Sgr A* proved difficult for scientists to visually capture: It’s a “dynamic environment” full of burbling and gurgling, Feryal Özel, a professor of astronomy and physics at the University of Arizona, told NPR. And the necessity to look through both the Earth’s atmosphere, gas clouds, and interstellar dust near the Milky Way’s center added to the challenge, Özel said. “It took several years to refine our image and confirm what we had, but we prevailed," Özel told NPR. And, despite its meager distance from Earth compared to Pōwehi, Sgr A* is far enough away to appear “to us to have about the same size in the sky as a donut on the Moon,” the EHT team stated <a href="https://eventhorizontelescope.org/blog/astronomers-reveal-first-image-black-hole-heart-our-galaxy">in a press release.</a>Hot gas whirling around Sgr A* at nearly the speed of light made capturing an image of this black hole considerably more difficult than Pōwehi, the EHT team said in the press release. “The brightness and pattern of the gas around Sgr A* was changing rapidly as the EHT was observing it,” EHT scientist Chi-Kwan Chan said in the press release.
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Images of Pōwehi captured by astronomers across the EHT were visually similar to one another, allowing scientists to compile a sharp composite image of Messier 87’s black hole. “That was not the case for Sgr A*,” the EHT team said in the press release. But despite these initial inconsistencies, the scientists were eventually able to compile an image of Sgr A*.Now, having images of such differently sized black holes provides a better look into the behavior of swirling gas around supermassive black holes, a phenomenon that’s not yet fully understood, but thought to play a key role in how galaxies, like our own, came to be. "Now we can study the differences between these two supermassive black holes to gain valuable new clues about how this important process works," EHT scientist Keiichi Asada said in the press release. 
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The Event Horizon Telescope team has captured the first image of Sagittarius A*, the black hole at the center of the Milky Way.

A man receives a coronavirus vaccine at Mass General Brigham's mobile clinic in Chelsea, Mass. Image Credit: Arlo Pérez Esquivel, WGBH

Addressing vaccine hesitancy in Massachusetts’ hardest-hit community

On a recent Sunday afternoon, Flor Amaya and <a href="https://www.massgeneralbrigham.org/">Mass General Brigham</a> health care workers drove a blue bus into the parking lot of Highland Park in Chelsea, Massachusetts. With this mobile clinic, the team aimed to vaccinate some of the Boston suburb’s younger community members and anyone who has had limited access to the COVID-19 vaccines.“You will find many people from many countries playing soccer at Highland Park on Sunday,” Amaya says. Eastern Europeans, Africans, and Latin Americans—people from countries where soccer is “big”—are known to frequent this field, she says. “That’s part of the reason why we chose that as a location,” says Amaya, who emigrated with her family from El Salvador to Massachusetts when she was nine years old. Now Chelsea’s director of public health, Amaya’s lived in Chelsea ever since.Parallel to the soccer field, the park’s concession stand advertises $3 horchata, popsicles, and the weekend’s vaccination clinic.
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Chelsea is a suburb of Boston “filled with essential workers, hardworking immigrants mostly from Central America,” <a href="https://www.boston25news.com/news/health/boston-doctors-will-volunteer-time-educate-chelsea-residents-about-vaccine/R62YR4V7M5BHJBXDQ4L4XKDIHM/">Boston 25 News reports</a>. About 67% of its residents identify as Hispanic. In 2020, Chelsea had the <a href="https://www.nytimes.com/2020/04/25/us/coronavirus-chelsea-massachusetts.html">highest COVID-19 infection rate</a> of any town in the state of Massachusetts, with nearly 4,000 cases per 100,000 people.“When you’d ask people how many are living in their home, it wasn’t uncommon for them to say, ‘Oh I have nine people living in my home; there are a couple families in one house’,” says Vivek Naranbhai, a clinical fellow at Dana Farber Cancer Institute who conducted pedestrian PCR testing in Chelsea in 2020.The weekly infection rates have since lowered, with <a href="https://www.chelseama.gov/COVID">64% of the Chelsea population</a> fully vaccinated against the coronavirus as of July 15. But the overall toll of COVID-19 on Chelsea—8,905 total cases among a population of just under 40,000 and 228 reported deaths—reflects the disproportionate way the virus has spread among underserved communities, particularly among <a href="https://www.cdc.gov/mmwr/volumes/70/wr/mm7011e1.htm">Hispanics and Latinos</a>.Amaya now organizes vaccine clinics, using her perspective as a city resident to better approach her community. Having lived in Chelsea for the last 29 years, Amaya has seen “the different chronic health conditions and lifestyle conditions that frequently plague minorities—ethnic communities—whether it is Latinx [or] African Americans,” she says. “I think a lot of us face similar challenges.”<a href="https://www.commonwealthfund.org/publications/newsletter-article/2021/jan/medical-mistrust-among-black-americans">Medical mistrust</a> among African Americans has been documented for more than 30 years, with the legacy of the infamous Tuskegee study serving as the basis for different research surrounding current attitudes toward health care in Black communities. But some cite ongoing <a href="https://www.npr.org/sections/health-shots/2021/03/23/974059870/stop-blaming-tuskegee-critics-say-its-not-an-excuse-for-current-medical-racism">discrimination</a> and racism from health care providers and the disproportionately high <a href="https://pubmed.ncbi.nlm.nih.gov/29346121/">Black maternal mortality rate</a>—as stronger drivers for medical mistrust today. Though research surrounding medical mistrust in the Latinx community is <a href="https://pubmed.ncbi.nlm.nih.gov/31343969/">not as extensive</a>, healthcare providers, religious leaders, and public health officials in majority Hispanic communities have observed hesitancy among those they serve firsthand.“It seems to be a very gut feeling that people who are resistant to getting the vaccine are experiencing,” Amaya says, “whether it is holding on to ideas of conspiracy theories, whether it is not trusting the government, or not trusting pharmaceutical companies.”
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<img alt="Chelsea, MA COVID vaccination mobile clinic" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/Chelsea_Vaxx_3.width-990_ejwN26G.jpg"/>
<figcaption>Healthcare providers stand behind Mass General Brigham's mobile vaccination clinic. Image Credit: Arlo Pérez Esquivel, WGBH
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Hosffman Ospino, a minister, professor, and chair of the Department of Religious Education at Boston College, has seen the effects of COVID-19 on his parish in Lawrence, Massachusetts, a city 26 miles north of Boston in which <a href="https://www.census.gov/quickfacts/lawrencecitymassachusetts">more than 80%</a> of residents identify as Hispanic or Latino. “It’s worrisome,” he says. “We know of a number of parishioners [who] have had the virus, and we know people in [Lawrence] who have died as well.” Because of the long history of mistreatment of people of color under medical care, whether the people Ospino serves hear true stories or myths about it, he says, “there’s a cultural distrust of medicine.”“We’ve been seeing vaccine hesitancy in general with Black and brown communities, says primary care doctor and Medical Director of MGH Chelsea HealthCare Center Dr. Dean Xerras. “We have always had issues around that in communities like Chelsea. I do see this as a long-term issue with education, engagement, and building trust.Building trust with our patients in our communities: that’s going to get us through this,” he says.This need for trust is driving Amaya, Ospino, and Dr. Xerras, and their organizations to both educate and create sensitive public health interventions for the communities most vulnerable to COVID-19.<h3>Barriers to vaccination</h3>Ospino, a Catholic theologian who works as a minister, is helping parishioners understand the nuances of how their religious beliefs intersect with health interests so they can make educated decisions. In December 2020, the Catholic church put out a statement condemning the use of the Johnson &amp; Johnson COVID-19 vaccine due to its use of <a href="https://www.gmp-creativebiolabs.com/per-c6-cell-lines_74.htm">PER.C6 stem cells</a>, a cell line derived from the retinal tissue of an 18-week-old fetus aborted in the Netherlands in 1985. (Dutch laboratory Crucell—which became Janssen Vaccines after being bought by Johnson &amp; Johnson in 2011—developed the cell line, which has been used in flu, tuberculosis, and malaria vaccines.)There is some nuance to the Church’s statement: Because Catholics have a moral obligation to pursue the common good (which is, during a pandemic, to get vaccinated), they can take the Johnson &amp; Johnson vaccine when no others are available. Still, there could be fear of “cooperating in an abortion” among Catholics nationwide, 38% to 40% of which self-identify as Hispanic. “Many people are confused,” says Ospino, adding that the vaccine “does not imply direct collaboration with abortions.” He says that a lack of Spanish-language resources about the stem cells contributes to a misunderstanding of the Johnson &amp; Johnson vaccine.
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And then in mid-April, the use of Johnson &amp; Johnson’s vaccine was paused due to rare but severe blood clots <a href="https://www.cdc.gov/media/releases/2021/s0413-JJ-vaccine.html">in six patients</a>. Amaya and her colleagues had been planning a Johnson &amp; Johnson vaccine clinic at a church in Chelsea just before the distribution pause. Many people from local congregations had signed up for the clinic, Amaya says, and while she and the faith leaders were planning it, the use of PER.C6 stem cells in developing the vaccine did not come into question.Amaya has noticed some hesitation in her Chelsea community toward the Johnson &amp; Johnson vaccine. But most people, she says, cite a fear of developing blood clots, not religious conviction. “It’s really hard to override those beliefs,” Amaya says. “We’re trying to figure out what it’s going to take right now to motivate people. We’re trying different modes of vaccine delivery. And for some people, it might just require time.”
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<figcaption>Community members line up behind Mass General Brigham's mobile clinic to receive Pfizer's coronavirus vaccine. Image Credit: Arlo Pérez Esquivel, WGBH
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In Chelsea, where religious leaders and healthcare providers alike are working to improve their community’s health, access to vaccination may be a greater issue than hesitancy and trust. Ospino says of the Catholic church’s recommendations, “most people actually will simply either ignore or somehow look at those issues and not understand them and then move on.”Among undocumented members in his community, Ospino sees fear of the legal system as a vaccination barrier. “In order to register, you have to give your name. Sometimes they ask for your address,” he says. Ospino recalls his own vaccination appointment at Boston’s Hynes Convention Center—a massive event center turned into a large-scale vaccination clinic. “When I went...what’s the first thing I see at the door? The military; the police and the military. So people are saying, ‘No way, I’m not going there!’” he says. “We need safe spaces for the immigrant community, spaces that are not threatening.”<h3>Meeting patients "where they're at"</h3>To create these safe spaces, Dr. Xerras believes it’s important to “meet patients where they’re at,” whether that be at churches, apartment buildings, or parks. And the ways the intersection of equity and health care is studied may also need to change, suggests Dr. John Iafrate, a pathologist at Massachusetts General Hospital. Researchers and health care providers, he and Dana Farber Cancer Institute clinical fellow Naranbhai explains, may shy away from creating tailored public health interventions in fear of being patronizing. “Many people don’t do these kinds of studies because they’re afraid to hurt the community or cause more mistrust,” says Dr. Iafrate, who with Naranbhai in 2020 set up a <a href="https://www.boston25news.com/news/health/antibody-testing-how-lessons-learned-chelsea-hotspot-are-shaping-testing-massachusetts/XUPJEBDX35BV7IMKWTBXDV5UQY/">COVID-19 antibody testing site</a> on the street in Chelsea in order to <a href="https://www.youtube.com/watch?v=GLQ9Alai5Ps">track the level of infection in the city</a>.Even as outsiders, Dr. Iafrate and Naranbhai were able to “meet a balance” to best serve the population and “tried hard to do it right,” Dr. Iafrate says. Their study included providers that spoke Spanish and represented members of the community, but most importantly, made participants feel safe, they say: The study did not collect information that could make participants feel like they would be tracked later, a key aspect of making a population where some people may have undocumented family members—or be undocumented themselves—feel comfortable.At the vaccination clinics she operates, Amaya pushes to have “people that represent the fabric of the community here in Chelsea,” she says. Her FEMA-supported vaccination clinic, based out of the Chelsea Senior Center, works with the nonprofit volunteer organization Chelsea Black Community to manage lines, registration, and other outdoor operations at the clinic. “We are multilingual, so we have Spanish speakers there to help with the consenting process,” she says. “We understand that a lot of people cannot read or write in their own native language, so we have the staff to verbally ask some of the screening questions and provide that support that people need.”
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<img alt="Coronavirus vaccination team at St. Patrick Parish in Lawrence, MA" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/St._Patrick_Parish_-_Lawrence_MA_-_Vaccination.width-990_n1EAeBr.jpg"/>
<figcaption>Hoffsman Ospino’s parish in Lawrence, Mass. has teamed up with Greater Lawrence Family Health Center to bring parishioners a walk-up, outdoor vaccine clinic in the church’s parking lot. “We continue to do our best to encourage vaccination and work for the common good,” Ospino said in an email. “It’s the least faith communities should be doing at this time.” Image courtesy of St. Patrick Parish, Lawrence, Mass.
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Amaya and her team’s community savvy helps the Department of Public Health and Mass General Brigham employ approaches that state government and faith-based organizations might overlook, including Chelsea’s Highland Park vaccination van.As community members start queuing up for their vaccine, Mass General Brigham site contact Damien Leach offers free personal protective equipment care kits and information about vaccination to them. People are very responsive to the <a href="https://www.massgeneralbrigham.org/newsroom/articles/mass-general-brigham-delivers-care-kits-vulnerable-populations">care kits</a>, Leach says, because the materials inside make navigating the pandemic—and adhering to state and CDC guidelines—easier. “I’ve had people try to give me $10 bills for these care kits,” he says. “We try to think about what the community needs and give it to them.”Inside the vaccination van, one health care provider draws up doses of the Pfizer vaccine, and Mass General Kraft Center medical director Dr. Priya Sarin Gupta vaccinates patients. She receives a vaccine syringe from the staff member inside the van, and in the blink of an eye, her patient—the first person in line at Highland Park that day—gets his first dose. Behind him, people play basketball, while just a few yards away, a crowd of spectators cheers loudly for their soccer team’s goal.“Could you make sure he knows he has to come back for a second shot?” Dr. Sarin Gupta asks her colleague, Eddie Taborda. Taborda steps out of the van and lets the patient know, in Spanish, to return for a second dose.
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Healthcare providers, religious leaders, and public health officials are coming together in Chelsea, Mass., a predominantly Hispanic community, to inform and vaccinate residents against COVID-19.

NOVA’s top 5 science stories of 2020

Uneventful but eventful, stagnant yet progressive: 2020 has been a year of contrasts for society as well as for science, medicine, and technology. Despite facing coronavirus-related setbacks, researchers made profound discoveries and helped people understand some startling realities. NASA’s OSIRIS-REx probe grabbed a piece of an asteroid, and the Japan Space Agency’s Hayabusa2 spacecraft returned samples of another asteroid to Earth. Scientists found signatures of water on the moon and nearby space rocks, and an obscure gas on our celestial neighbor, <a href="https://www.youtube.com/watch?v=htcj0G3yjsA&amp;t=146s">Venus</a>. Meanwhile, other scientific endeavors—like <a href="https://www.pbs.org/wgbh/nova/video/antarctic-extremes-thwaits-icefin-threatened-glaciers/">climate change research</a> at the poles—faced a freeze as the pandemic brought “normal” life here on Earth <a href="https://www.youtube.com/watch?v=rgz9CZzR2Dk&amp;t=1s">to a halt</a>. COVID-19 had a devastating, disproportionate impact on people of color in the U.S., bringing new attention to racial disparities in health and medicine. And as widespread protests triggered a societal reckoning with police brutality and systemic racism, many in the scientific community celebrated Black scientists and trailblazers in STEM fields.
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<h3>1. COVID-19 pandemic strikes; scientists race to understand and contain the virus</h3>The <a href="https://www.pbs.org/wgbh/nova/video/decoding-covid-19/">COVID-19 pandemic</a> of 2020 was the biggest worldwide event of the year, and unfortunately, it’s not over yet. On Dec. 31, 2019, the World Health Organization announced that pneumonia from an unknown source, later to be identified as the novel coronavirus, had sickened dozens of people in Wuhan, China. Then, on Jan. 21, 2020, a Washington state resident who had traveled to Wuhan became the first-reported American to contract the coronavirus. The first U.S. cases of non-travel-related COVID-19 were confirmed in late February, marking the earliest confirmation of community transmission, <a href="https://www.cdc.gov/mmwr/volumes/69/wr/mm6922e1.htm#:~:text=One%20possible%20early%20source%20is,%2C%20on%20January%2015.">the CDC reported</a>. By the end of April, after watching <a href="https://apnews.com/article/pandemics-europe-italy-coronavirus-pandemic-france-7594be9ff72658f7c49d9312609e8c34">hard-hit countries like Italy</a> experience harrowing daily death tolls, 1 million Americans had contracted SARS-CoV-2, the virus responsible for COVID-19.At the same time, an unprecedented global effort to understand and contain the virus—and find a treatment for the disease it causes—was already underway. Now, as 2020 comes to a close, we’ve learned how a pandemic can affect the medical supply chain and availability of personal protective equipment (PPE), and the measures health care workers have taken to try to make sure <a href="https://www.pbs.org/wgbh/nova/article/covid19-ventilators-sharing-safe/">everyone gets treatment</a>. We’ve watched researchers quickly <a href="https://www.youtube.com/watch?v=an9W0tAOe80">develop vaccines</a>, and even <a href="https://www.pbs.org/wgbh/nova/article/polio-pandemic-coronavirus-vaccine/">drawn inspiration from the past</a> to learn how to better navigate life in a locked-down world. And COVID-19 has illustrated many ways that  long-standing health and social inequities have put Black, Indigenous, and people of color at an increased risk of illness.With FDA approval of both the <a href="https://www.pbs.org/wgbh/nova/article/pfizer-moderna-covid-vaccines-clinical-trials/">Pfizer/BioNTech and Moderna vaccines</a>, several more vaccines in clinical trials, and <a href="https://www.youtube.com/watch?v=COKn_1J522s">vaccination efforts underway</a>, some epidemiologists and healthcare providers are looking to 2021 with optimism. But skepticism toward the already-approved vaccines, both of which use new mRNA technology, exists with <a href="https://www.pewresearch.org/science/2020/12/03/intent-to-get-a-covid-19-vaccine-rises-to-60-as-confidence-in-research-and-development-process-increases/">as many as 40% of Americans</a> saying they do not plan to get vaccinated, according to polls taken Nov. 18-29. Fueled by a history of medical mistreatment, many Black and Indigenous Americans remain <a href="https://time.com/5925074/black-americans-covid-19-vaccine-distrust/">wary toward coronavirus vaccines</a>, making <a href="https://www.npr.org/sections/health-shots/2020/12/16/942452184/california-may-consider-historical-injustice-when-allocating-coronavirus-vaccine">addressing racial and social equities</a> during their distribution paramount.
<h3>2. OSIRIS-REx snags sample of an asteroid; Hayabusa2 returns an asteroid sample to Earth</h3>In the pursuit to better understand the history of our solar system and Earth, NASA’s <a href="https://www.pbs.org/wgbh/nova/video/touching-the-asteroid/">OSIRIS-REx</a> and the Japan Space Agency’s <a href="https://www.pbs.org/wgbh/nova/article/hayabusa2-returns-asteroid-ryugu-sample/">Hayabusa2</a> space missions set out to sample rock, dirt, and debris from space rocks. On Tuesday, Oct. 20, the OSIRIS-REx probe <a href="https://www.pbs.org/wgbh/nova/article/osiris-rex-bennu-asteroid-touchdown/">successfully touched down</a> on the surface of Bennu, a space rock about 200 million miles from Earth. Its team briefly feared that they may have bit off more than it could chew: OSIRIS-REx scooped up so much material from Bennu that its sampling container became jammed open, causing asteroid bits to leak out and forcing <a href="https://www.pbs.org/wgbh/nova/article/nasa-osiris-rex-spacecraft-stow-asteroid-bennu-sample-early/">an early stow</a> of the sample. (The OSIRIS-REx team aimed to collect at least 60 grams, or 2.1 ounces, of rock and dust from Bennu.) In more than two years, as it passes over the Utah desert, OSIRIS-REx will drop off a small capsule containing its sample, which will parachute to a landing—and a team of eager scientists—in September 2023.
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On Dec. 8, the Hayabusa2 spacecraft <a href="https://www.pbs.org/wgbh/nova/article/hayabusa2-returns-asteroid-ryugu-sample/">returned a sample from Ryugu</a>, an asteroid 180 million miles away, to Earth. The Hayabusa2 team successfully collected a surface and a subsurface sample from Ryugu in 2019 after deploying hopping robots to identify a safe sampling spot. The sample parachuted to the red desert sand of the Australian Outback, where a Japan Space Agency recovery team collected it. Now, the team is analyzing the <a href="http://www.hayabusa2.jaxa.jp/en/topics/20201225_samples/">black, gravelly sample</a>, which includes chunks of rock larger than 1millimeter. Some 10% of the material will be sent to NASA in December 2021 in exchange for samples from asteroid Bennu. Another 15% will be made available to international researchers, and about 40% will be stored for future scientists to investigate, Smriti Mallapaty <a href="https://www.nature.com/articles/d41586-020-03451-6">reports for Nature News and Comment</a>.Scientists suspect that when asteroids like Ryugu and Bennu pummeled a proto-Earth billions of years ago, they may have helped kick-start life by delivering the necessary building blocks.
<h3>3. Racial disparities in science and medicine persist; #BlackinSTEM weeks foster inclusivity and empowerment</h3>Discussions about inclusivity and racial disparities in science, medicine, and technology—and coronavirus treatment and prevention—have come to the forefront this year. In June, amid the turmoil of COVID-19, the senseless killings of George Floyd, Breonna Taylor, Ahmaud Arbery, and other Black Americans catalyzed protests across the U.S. and spotlighted police brutality, systemic racism, and the <a href="https://www.nytimes.com/2020/12/09/health/coronavirus-black-hispanic.html">disproportionate effect of the pandemic</a> on people of color.As of July, Native Americans were hospitalized for extreme coronavirus symptoms more than five times as often as white people, with hospitalization rates among Latino and Black Americans similarly high, <a href="https://www.cdc.gov/coronavirus/2019-ncov/community/health-equity/race-ethnicity.html">the CDC reported</a>. Despite making up only about 13% of the population, Black Americans represent nearly a quarter of COVID-19 deaths in the U.S. And according to <a href="https://www.nytimes.com/interactive/2020/07/05/us/coronavirus-latinos-african-americans-cdc-data.html">CDC data reported on May 28</a>, African American and Latinx residents of the U.S. are three times more likely to contract the coronavirus and nearly twice as likely to die from the virus as their white neighbors. <a href="https://www.nytimes.com/2020/12/09/health/coronavirus-black-hispanic.html?searchResultPosition=2">Inequities</a> in healthcare access and utilization, occupation, housing, and educational, income, and wealth affecting racial and ethnic minority groups “are interrelated and influence a wide range of health and quality-of-life outcomes and risks,” the CDC reported. <a href="https://www.pbs.org/wgbh/nova/article/racism-stress-covid-allostatic-load/">Chronic stress brought on by racism</a> can cause wear and tear on the body, potentially increasing individuals’ risk of hypertension, depression, diabetes, and other underlying conditions linked with more severe cases of COVID-19. Amid protests against systemic racism, the scientific community asked: What does it mean to be Black in STEM? For many Black researchers, like <a href="https://www.pbs.org/wgbh/nova/article/blackinnature-tropical-paleontology/">paleobiologist Melissa Kemp</a>, it means perseverance, resistance, and passion. Highlighting <a href="https://www.pbs.org/wgbh/nova/article/inaugural-black-x-weeks-foster-inclusivity-and-empowerment-stem/">#BlackinSTEM</a> folks from summer onward, various “Black in___” weeks gave us a look into the experiences and perspectives of Black experts and scholars in astronomy, neuroscience, math and more. For Kemp, #BlackinNature and the conversations it sparked were important, she said, because they reinforced, “particularly for us as Black people, that we belong here, that this country is ours. We had a very, very instrumental part in creating what we have today in this country, even as we continue to be oppressed. I think it's also important for non-Black people to hear that as well, that they recognize those contributions.”
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<figcaption>Black Birders Week has united environmental professionals across the globe. In this photo, Black Birders Week co-organizer Corina Newsome is surrounded by birds of North America, including her spark bird, the blue jay. Illustration By: Aliisa Lee
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<h3>4. Despite coronavirus lockdowns, climate change intensifies</h3>In the fall of 2019, a crew set out to lock its 400-foot icebreaker ship named Polarstern in a sheet of floating Arctic ice for 13 months as part of the Multidisciplinary drifting Observatory for the Study of Arctic Climate (<a href="https://www.pbs.org/wgbh/nova/article/mosaic-polarstern-departs/">MOSAiC</a>), an endeavor to monitor climate change at the <a href="https://arcticwwf.org/work/climate/">fastest-warming part of our planet</a>. Unfortunately, polar climate research projects like MOSAiC and the International Thwaites Glacier Collaboration, a climate research program on <a href="https://www.pbs.org/wgbh/nova/article/warm-water-found-beneath-thwaites-glacier-antarctica/">Antarctica’s “doomsday” glacier</a>, have been put on hold because of the pandemic-related travel restrictions. (Antarctica had been free of COVID-19 until Dec. 22, when Chilean officials reported an outbreak of <a href="https://www.livescience.com/antarctica-covid-19-outbreak.html">36 COVID-19 cases</a> at a Chilean research base.)Although some climate research has faced delays or come to a standstill, climate change hasn’t. Temporary reductions to carbon emissions, thanks to pandemic shutdowns, are just a blip in the upward trajectory of global greenhouse gas emissions, Bob Berwyn <a href="https://insideclimatenews.org/news/23112020/covid-19-coronavirus-shutdowns-greenhouse-gas-emissions/">reports for Inside Climate News</a>: Though 2020’s emissions will drop by 4-7% as compared to 2019’s, atmospheric carbon dioxide levels will increase, the World Meteorological Organization found.
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January 2020 was marked by the <a href="https://www.nytimes.com/2020/01/21/world/australia/fires-size-climate.html">Australian bushfires</a>, the first in a devastating series of wildfires and other natural disasters <a href="https://www.pbs.org/wgbh/nova/video/inside-the-megafire/">likely worsened by climate change</a>. Similarly, <a href="https://www.scientificamerican.com/article/californias-mega-fires-have-arrived-30-years-early/">megafires occurring in California</a>, <a href="https://www.cpr.org/2020/08/20/colorado-wildfires-climate-change-drought-snowpack/">Colorado</a> and<a href="https://theconversation.com/historic-amazon-rainforest-fires-threaten-climate-and-raise-risk-of-new-diseases-146720"> the Amazon</a> this year were exacerbated by dry climate conditions—an environmental shift that may become the “new norm” as rainfall in temperate areas decreases. “I think the frequency of these kinds of summers where we get in these hot, dry conditions is probably going to increase,” climatologist Russ Schumacher <a href="https://www.cpr.org/2020/08/20/colorado-wildfires-climate-change-drought-snowpack/">told Colorado Public Radio</a>. “When the pattern sets up for these hot, dry periods of time, they're going to be more intense. That's what we've seen the last few years here,” he added.Despite pandemic shutdowns, young activists like Greta Thunberg are still finding ways to fight for a greener future. “All movements have had to step back during this pandemic, because that’s simply what you have to do during the crisis,” Thunberg <a href="https://time.com/5918448/greta-thunberg-coronavirus-climate-change/">told TIME Magazine</a>. In late November, more than 350 young activists from around the world held a two-week virtual climate summit called Mock COP 26, which aimed to <a href="https://time.com/5916293/mock-cop26-youth-climate-activists/">elevate the voices</a> of young people on the front lines of the climate crisis in developing countries, Suyin Haynes writes for TIME Magazine.
<h3>5. Scientists discover molecules on three of our celestial neighbors</h3>In August, a team of researchers announced an <a href="https://www.pbs.org/wgbh/nova/article/dwarf-planet-ceres-water-geologically-active/">exciting find on Ceres</a>, the largest asteroid in our solar system. Using high-resolution images collected by NASA’s Dawn Orbiter, the team found that Ceres has water seeping onto its surface, suggesting the presence of an ancient underground ocean. The liquid, the researchers concluded, comes from an underground reservoir of saltwater 25 miles beneath Ceres’ Occator Crater. The reservoir may be hundreds of miles wide and could still be actively dribbling briny liquid onto the asteroid’s surface, some scientists believe. Skeptics caution, however, that water on the dwarf planet’s surface doesn’t entail the presence of an underground ocean but perhaps a smaller reservoir.
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<figcaption>The dwarf planet Ceres, photographed by NASA’s Dawn orbiter. False-color renderings highlight differences in its surface materials. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
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The search for water and other molecules in space didn’t stop with Ceres: In October 2020, NASA announced that, by using its Stratospheric Observatory for Infrared Astronomy (SOFIA) telescope on a Boeing 747SP airplane, its scientists discovered water on the surface of the moon. Equipped with an onboard infrared camera, SOFIA detected the specific wavelength unique to water molecules, finding a relatively dense concentration of water in the moon’s sunny Clavius Crater in its southern hemisphere. The discovery indicates that water may be distributed across the lunar surface, and not limited to cold, shadowed places. The finding raises some intriguing questions: “Without a thick atmosphere, water on the sunlit lunar surface [would] just be lost to space,” NASA postdoctoral fellow and lead author Casey Honniball said in <a href="https://www.nasa.gov/press-release/nasa-s-sofia-discovers-water-on-sunlit-surface-of-moon/">a NASA press release</a>. “Yet somehow we’re seeing it. Something is generating the water, and something must be trapping it there,” she added.In September, <a href="https://www.pbs.org/wgbh/nova/video/signs-life-venus/">scientists found a gas called phosphine</a> in Venus’ atmosphere. Phosphine, which is found in oxygen-free environments, is associated with microbial life on Earth. Its presence on Venus could hint at signs of life in the planet’s atmosphere—an environment often considered to be too hot and sulfuric to be habitable. Astronomer Jane Greaves used the James Clerk Maxwell Telescope in Hawaii to detect the first signal of phosphine in Venus’ atmosphere. She and her team then used the Atacama Large Millimeter Array Telescope (ALMA), a more powerful telescope in the high deserts of Chile, to pick up a much stronger phosphene signal. “I think it could be game-changing for everyone. Not just because it would mean that there's life next door, which in itself, I think is a big enough deal,” astrochemist Clara Sousa-Silva, who was involved in the study, told NOVA. “It might just be extremely common and inevitable, which means that there's thousands and thousands of possibilities for life in the galactic neighborhood just waiting to be discovered.”But some enthusiasm has dissipated in the months since the big announcement, Marina Koren <a href="https://www.theatlantic.com/science/archive/2020/12/life-on-venus-the-debate-is-far-from-over/617331/">reports for The Atlantic</a>. “The science community is divided—enough that one rebuttal <a href="http://astrobiology.com/2020/10/no-phosphine-in-the-atmosphere-of-venus.html">paper</a> had the authors ‘invite’ the researchers who originally identified the phosphine to consider retracting their study altogether,” she writes. While the team expected criticism, it didn’t expect to have a problem with the raw data from one of the telescopes involved in the research, which had been used to confirm the presence of phosphine. <a href="https://arxiv.org/abs/2012.05844">Reanalyses</a> show that the gas is present in Venus’ atmosphere, but the signal is far fainter than originally reported.
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Asteroid samples and strange space molecules wowed us—while past epidemics taught us valuable lessons.

Red hot chili peppers, and other hot peppers within the Capsicum genus, get their heat from the chemical capsaicin. Image credit: Austin Kirk, Flickr

From jumping horses to jalapeños: the science of spicy peppers

A few months after competing in the 2008 Summer Olympics in Beijing, Norweigian horseback rider Tony André Hansen was stripped of his bronze medal. His horse Camiro had failed a drug test during the Games, testing positive for capsaicin. The International Equestrian Federation <a href="https://www.nytimes.com/2008/08/22/sports/olympics/22doping.html">dismissed the pair</a>, along with three other showjumping riders and horses, from the competition. Hansen has not competed in the show ring since.Capsaicin is the chemical responsible for the “heat” in chile peppers. Like many over-the-counter muscle rubs—think “IcyHot”—capsaicin can bring on both tingling sensitivity and numbness.
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When applied as a <a href="https://www.reuters.com/article/us-olympics-equestrian-doping/norway-bronze-medalist-suspended-idUSPEK303420080821">paste or lotion to horses’ forelegs</a>, capsaicin can cause a burning sensation that would be exacerbated by knocking against the rails of a jump. If a showjumping horse lifts its legs higher, it avoids the potentially irritating touch of a fence—and its rider avoids incurring penalties. But capsaicin can also soothe aches and pains by temporarily <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6006555/">deactivating the nerve endings</a> where it’s applied. An exhausted horse with numbed nerves will perform better than an equally tired one that can feel the full pain of its aching muscles, according to the <a href="https://aaep.org/horsehealth/lameness-and-poor-performance-sport-horse-eventing">American Association of Equine Practitioners</a>, which is why capsaicin is banned from equestrian competitions to this day. “Capsaicin binds to the TRPV-1 receptor—a pain receptor present all over our bodies,” says Ivette Guzmán, a horticulturist and member of the Chile Pepper Institute of New Mexico State University. If a horse is sore, “applying capsaicin binds up those pain receptors,” she says. A horse may feel a little bit of heat from topical capsaicin, but “they won’t feel the pain,” Guzmán explains. “It works on us, too.”Just as horses experience a numbing feeling from a topical application of capsaicin, your tongue will tingle when you chew a hot pepper. This numbing sensation is often coupled with a burning one that’s enjoyed by spicy food-lovers around the world: Whether eating centuries-old cuisines like <a href="https://www.theatlantic.com/health/archive/2019/04/why-we-call-indian-dishes-curry-colonial-history/586828/">Indian curry</a> or saucy chicken wings on the popular YouTube series “Hot Ones,” human beings have subjected themselves to the uncomfortable chemistry of capsaicin <a href="http://sitn.hms.harvard.edu/flash/2012/issue131b/">for millennia</a>.<h3>The need for heat</h3>Pepper species native to the Americas fall within the genus Capsicum. Some Capsicum peppers, like the mild bell pepper, have no capsaicin at all. Others, like the jalapeño and habanero pepper—popular additions to dishes requiring some extra “heat”—do have the chemical. (A few Capsicum peppers, including the incredibly-hot ghost pepper, were developed in South Asia by hybridizing varieties from the Americas.)“A lot of people mistakenly think the seeds are what hold the spice,” Guzmán says. But “capsaicin is found in the part of the fruit called the placenta: the membrane that holds onto the seeds.”But spicy food doesn’t have to be hot to convey heat. In fact, capsaicin doesn’t physically burn your tongue and innards at all. When your body processes capsaicin, your nervous system sends out a response that activates your senses for touch and temperature. The same receptors responsible for blocking topical pain send signals to your brain that you’re being burned when you eat something spicy. And here’s the kick: Capsaicin alters the sensitivity of the pain receptors in your mouth, effectively lowering the temperature at which you feel burning pain. This is why jalapeño sauce feels burning hot even after being refrigerated.“These [receptors] work really well when they detect the correct stimulus,” says Joanna Buckley, a chemist at the University of Sheffield in England. “They respond to anything over 43 C (109 F). So if you have a hot cup of tea, this receptor will work correctly and tell you, ‘Oh, your tea’s a bit hot.’” The problem is, Buckley adds, these heat-sensing receptors are also triggered by a class of compounds called vanilloids. Capsaicin is one of them.
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Chemically, capsaicin is corrosive (like hydrogen peroxide), acutely toxic (like chlorine), and irritating (like ammonia). And its irritant qualities won’t just fire up your mouth: Capsaicin can have a similar effect on other mucous membranes. If you’ve ever chopped peppers and then accidentally touched your eye, you understand how irritating this compound can be. So why do some people enjoy—and even get a thrill out of—eating a fruit with such a kick?“We get interviewed often by chiliheads,” Guzmán says. “I’m Mexican. I grew up eating jalapeños, I grew up eating really spicy food, and I understand that there are other chemicals in [peppers] that are medicinal. But when it comes to chiliheads, I think they’re fascinated by the chemistry of capsaicin and how it makes you feel something you’ve never felt before. It gives you a euphoria.” Measuring that euphoria depends on the Scoville scale.<h3>Let’s talk Scovilles</h3>Named for American pharmacist Wilbur Scoville, <a href="https://www.vox.com/2016/1/22/10810564/wilbur-scoville-google-doodle">the Scoville scale</a> ranks the pungency of chile peppers based on the concentration of capsaicin in the pepper. It’s this concentration that determines how our bodies will react to peppers; while small amounts of capsaicin fall within the “spicy chicken dinner” category, stronger concentrations spell out “weapon-grade pepper spray.” In the early 1900s, Scoville, who was working as a chemist at the time, attempted to test out people’s relative capsaicin tolerance. He recruited five human subjects to taste-test mixtures of dried pepper and sugar water and had them report how hot they found each mixture to be. The basis of his heat scale is the amount of sugar water needed to dilute the mixture enough for the majority of his subjects to no longer feel the heat. These days, a technique called high-performance liquid chromatography is used to determine exactly how much capsaicin a pepper contains in parts per million, and multiplying the result by 16 converts it to <a href="https://www.smithsonianmag.com/arts-culture/how-hot-is-that-pepper-how-scientists-measure-spiciness-884380/">Scoville Heat Units (SHUs)</a>.
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The highest level of naturally occuring capsaicin is in the Carolina Reaper, the hottest pepper in the world. Its creator, chile pepper grower Ed Currie, bred the pepper by taking one uniquely spicy <a href="https://www.palmettobluff.com/discover/fear-the-reaper">habanero</a> grown on the La Soufrière volcano on Saint Vincent in the Caribbean and crossing it with a Naga Viper pepper, which was developed in the United Kingdom from peppers hailing from the Caribbean and South Asia. The hottest single Carolina Reaper ever to be harvested rang in at 2.2 million SHU, meaning that more than a tenth of the pepper was pure capsaicin.High amounts of capsaicin, like those found in the Carolina Reaper, can cause injury. “Capsaicin is a really potent chemical. If you have too much of it, it can be toxic,” Buckley says. “It’s the thing that’s used in pepper spray. We’ve all seen images of people who have been pepper sprayed. Their eyes are swollen up, they’re crying, they can’t see…so it’s incredibly important to know how to handle capsaicin” safely, she says.<h3>Your body’s battle against spice</h3>If you don’t welcome spicy burns, there’s a way to neutralize the compound’s effects: dairy. “Capsaicin is an oil and it is insoluble in cold water,” Buckley says. Though it’s somewhat soluble in alcohol, like beer, Buckley explains, capsaicin is best dissolved by another oil. “You need to find something that’s fatty to dissolve the capsaicin,” she says. “That’s why the best thing to drink is milk.” Although spicy food is sometimes associated with stomach problems—Currie, who not only created the Carolina Reaper but also eats one every day, still <a href="https://www.latimes.com/nation/la-na-reaper-pepper-20141127-story.html#">experiences severe stomach cramps</a>—there is no direct evidence that spicy food causes belly cramps or nausea. The perceived pain, Guzmán explains, may just be a side effect of your gut membranes being irritated. While a 2016 study showed capsaicin can cause those with abdominal disorders to experience <a href="https://pubmed.ncbi.nlm.nih.gov/27094759/">flare-ups in their symptoms,</a> the same can be said for <a href="https://www.pbs.org/wgbh/nova/article/unless-you-have-celiac-disease-gluten-sensitivity-is-probably-just-in-your-head/">too much bread</a>, a famously unspicy food.But there are always worst-case scenarios.
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<img alt="Trinidad scorpion pepper" class="richtext-image full-width" src="https://staging.pbs.org/wgbh/nova/media/images/Trinidad_Scorpion_Pepper.width-990_7SVn9Gn.jpg"/>
<figcaption>A Trinidad moruga scorpion pepper, which is currently the second hottest pepper in the world to the Carolina reaper. Image credit: John Vonderlin, Flickr
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More than 150 different varieties of chile grow in a garden at New Mexico State University’s Chile Pepper Institute. “One year we had a group of students we were doing a tour with in the garden. And one student thought it would be funny if he bit a tiny piece off a Trinidad Scorpion pepper,” Guzmán says. “He did that, and he threw up in the garden, and he passed out, and we had to carry him to a shaded area under some trees.” Because capsaicin is a toxin, Guzmán explains, the human body’s first response to an excess of it is to flush it out. (In the student’s case, by vomiting.) In 2018, the <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5893965/">National Institutes of Health reported</a> that a previously healthy 34-year-old man was admitted to the hospital with “thunderclap headaches”—sudden, severe head pain accompanied by fever, blurred vision, and even seizures—after eating a Carolina Reaper whole. Doctors treated him by flushing the capsaicin out of his body, which, like many chemical compounds in large amounts, can be dangerous. Of course, Olympic equestrian Tony André Hansen’s story shows that even a small amount of this complex compound can be damaging (and in some cases, even career-ruining). It just depends on where—or upon whom—the capsaicin ends up.
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Discover capsaicin, the active ingredient in chile peppers. (If you can take the heat.)

Katherine Julian, physician and associate dean of graduate medical education at the University of California, San Francisco (UCSF). Image courtesy of UCSF

A physician on her grandfather’s experience as a minority in STEM—and the state of progress today

The grandson of Alabama slaves, Percy Julian worked tirelessly—transitioning from university classrooms to private laboratories; from the U.S. to Austria and back—to find a place that would allow him to work in chemistry. After one year as a department head at Howard University—a stint <a href="https://www.pbs.org/wgbh/nova/video/forgotten-genius/">that ended in his resignation</a>—Julian would go on to work at DePauw University, where he became the first to ever totally synthesize physostigmine, an alkaloid used to treat glaucoma.His other successes, which include synthesizing cortisone (used to treat arthritis) and progesterone (used to prevent miscarriages) improved society. They also helped pave the way for Black, Indigenous, and other people of color in STEM, and <a href="https://www.pbs.org/wgbh/nova/article/percy-julian/">inspire the next generation of scientists</a>.
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One of those scientists is Percy Julian’s granddaughter, Katherine Julian. A physician and associate dean of graduate medical education at the University of California, San Francisco, Katherine trains medical residents and fellows, and researches medical education. Her work of practicing science and educating others mirrors—and honors—her grandfather’s legacy, and she sees Percy Julian’s sacrifices reflected in the work she and other Black scientists do today. A lot of Black people “have to work three times as hard” to be taken seriously, Katherine says. “I think that kind of work ethic is something that I have to continue to uphold—certainly in my professional world. That has been instilled in me in a lasting manner.” Katherine spoke with NOVA about her memories of Percy, her career, and the effect his life and work has had on the way she perceives progress in STEM today.Hanna Ali: <a href="https://www.pbs.org/wgbh/nova/article/blackinnature-tropical-paleontology/">Black scientists</a> and <a href="https://www.pbs.org/wgbh/nova/video/joys-challenges-birding-while-black-christian-cooper/">hobbyists</a> still face discrimination in the lab and in public, much like Percy Julian did himself. More often than not, the onus is on Black, Indigenous, and other people of color to push their way into STEM environments and educate their peers on what it means to treat them with humanity.Do you often find that your cohort of students is fairly diverse, and have you seen more strides being made at UCSF to make more opportunities for students of color?Katherine Julian: In my almost 25-year career—and I think this is not just at UCSF, this is on a larger scale—we’ve made great strides to become more diverse in science. Do I think we are where we need to be? No, of course not. And I still feel like we have a ways to go. We are not perfect. We have many things to learn and change. But I do feel like we are at a unique point—particularly now—because, unfortunately, of many current events. There is more consciousness-raising presently than I have seen in the last 20 years. I feel like that’s an incredible opportunity to be able to continue to make change.HA: In the time that your lives overlapped, did you witness your grandfather working as a chemist? If so, what impression did this leave on you?KJ: Well, he passed away when I was pretty young. The side that I saw of him was not necessarily the scientist side. I saw a side that was super passionate about gardening: the garden he had, around his house [in Chicago] and on the grounds of his home. He loved tulips—and planted thousands and thousands and thousands of tulip bulbs in the ground. [He’d] go out and garden every morning before going to work. I think it does reflect that he was someone who worked so incredibly hard. I think he was someone that put himself fully into many, many things. Obviously he had science. And moving that forward and to do the things that he did, I think required such incredible fortitude.HA: Did your grandfather use gardening as a way to educate the younger children in your family?KJ: I definitely remember being out there with him. I was probably too young for there to be any sort of education aspect. But I do think after he passed away, there has been an education aspect: from my grandmother and my father and my aunt, in terms of his legacy and what that meant, and almost a responsibility for that legacy. And that goes a little bit toward having to work twice as hard and how important education is. I think that there was very much a feeling that he had worked so hard to be able to advance Black and African Americans and to be able to provide for his family. HA: It seems like, instead of a hands-on teaching approach, there was more of a legacy of learning.KJ: That’s exactly right. 
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HA: “Forgotten Genius” offers a perspective of Percy Julian’s career and also suggests that he made lots of friends along the way, including some overseas in Austria, that came to do research with him in the States later on. Are you in touch with any of them?KJ: You know, I actually am in touch with a family friend—she's now of advanced age. Her family worked with my grandfather. She now lives in Israel. She travels to the U.S. once a year—well, not in COVID times—usually for competitions. She's a scientist herself, and we get together every year when she comes. So there is some of that connection, obviously, because my grandfather now would be very old, and a lot of those connections have now passed. Staying in touch with her [has] really been terrific. And [being] able to hear old stories has been great. 
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HA: It’s interesting to think about how Percy Julian had to go out of the country just to get more research and work experience. KJ: And to encounter all of the racism and barriers there—just even to try and live in the community of what he was trying to live—I think required incredible fortitude. HA: My family members are immigrants, and we don’t have that sort of long story of a family legacy in America. It’s more like, “Your parents came here to go to school and they made a life for themselves. Any sort of family history is back in Somalia.” KJ: I see an immigrant's story in a way very similar to the way you think back to fortitude. How hard it is to leave everything behind, to go someplace new to try and make a better life—whether it's for you or often really for your kids—right? So I see it as very, very similar. I can't speak for children of immigrants, but having spoken to several of my friends, I do think they also feel a big responsibility. It's like, “Wow, my parents went through all of this for me…I have a responsibility to pay that forward in a way.” HA: We’ve been highlighting <a href="https://www.pbs.org/wgbh/nova/article/inaugural-black-x-weeks-foster-inclusivity-and-empowerment-stem/">"Black in X" weeks at NOVA</a>, talking about what it means to be a Black scientist. Being a physician, do you find yourself having to explain the most basic inequities in health care or STEM to your peers, where you say something like, “I shouldn’t have to tell you this, but I do?”KJ: You know, not so much now. Some of that is a function of the stage I'm at in my career, [and] where I'm at, being at UCSF, where I do think people are really looking at <a href="https://www.pbs.org/wgbh/nova/video/covid-19-vaccine/">health equity</a> in a real way and thinking deeply about it. I do feel fortunate that I am not having those conversations in my workplace, at least presently. I have, years and years ago, [but] I do feel that that's a marker where I am in terms of change. Because I also recognize that's not the case for many, many other people and where they are. The current pandemic has just uncovered so much <a href="https://www.pbs.org/wgbh/nova/article/racism-stress-covid-allostatic-load/">health inequity.</a> And I think people—at least the folks I’m working with—realize that. I do think folks are really looking and thinking about “How can we, as a medical community, make a difference in terms of really trying to eliminate those disparities and help?” This interview has been edited for length and clarity.
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Dr. Katherine Julian, the granddaughter of famed chemist Percy Julian, discusses her grandfather’s legacy—and how barriers for people of color in science still exist.

Hanna Ali

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