Why Neglected Tropical Diseases Should Matter to Americans
Daisy Hernández was five years old when one of her favorite aunts was struck with a mysterious illness. Tía Dora had stayed behind in Colombia when Daisy's mother immigrated to Union City, New Jersey. A schoolteacher in her late 20s, she began suffering from fevers and abdominal pain, and her belly grew so big that people thought she was pregnant. Exploratory surgery revealed that her large intestine had swollen to ten times its normal size, and she was fitted with a colostomy bag. Doctors couldn't identify the underlying problem—but whatever it was, they said, it would likely kill her within a year or two.
Tía Dora's sisters in New Jersey—Hernández's mother and two other aunts—weren't about to let that happen. They pooled their savings and flew her to New York City, where a doctor at Columbia-Presbyterian Medical Center with a penchant for obscure ailments provided a diagnosis: Chagas disease. Transmitted by the bite of triatomine insects, commonly known as kissing bugs, Chagas is endemic in many parts of Latin America. It's caused by the parasite Trypanoma cruzi, which usually settles in the heart, where it feeds on muscle tissue. In some cases, however, it attacks the intestines or esophagus. Tía Dora belonged to that minority.
In 1980, U.S. immigration laws were more forgiving than they are today. Tía Dora was able to have surgery to remove a part of her colon, despite not being a citizen or having a green card. She eventually married a legal resident and began teaching Spanish at an elementary school. Over the next three decades, she earned a graduate degree, built a career, and was widowed. Meanwhile, Chagas continued its slow devastation. "Every couple of years, we were back in the hospital with her," Hernández recalls. "When I was in high school, she started feeling like she couldn't swallow anything. It was the parasite, destroying the muscles of her esophagus."
When Tía Dora died in 2010, at 59, her niece was among the family members at her bedside. By then, Hernández had become a journalist and fiction writer. Researching a short story about Chagas disease, she discovered that it affected an estimated 6 million people in South America, Central America, and Mexico—as well as 300,000 in the United States, most of whom were immigrants from those places. "I was shocked to learn it wasn't rare," she says. "That made me hungry to know more about this disease, and about the families grappling with it."
Hernández's curiosity led her to write The Kissing Bug, a lyrical hybrid of memoir and science reporting that was published in June. It also led her to another revelation: Chagas is not unique. It's among the many maladies that global health experts refer to as neglected tropical diseases—often-disabling illnesses that afflict 1.7 billion people worldwide, while getting notably less attention than the "big three" of HIV/AIDs, malaria, and tuberculosis. NTDs cause fewer deaths than those plagues, but they wreak untold suffering and economic loss.
Shortly before Hernández's book hit the shelves, the World Health Organization released its 2021-2030 roadmap for fighting NTDs. The plan sets targets for controlling, eliminating, or eradicating all the diseases on the WHO's list, through measures ranging from developing vaccines to improving healthcare infrastructure, sanitation, and access to clean water. Experts agree that for the campaign to succeed, leadership from wealthy nations—particularly the United States—is essential. But given the inward turn of many such countries in recent years (evidenced in movements ranging from America First to Brexit), and the continuing urgency of the COVID-19 crisis, public support is far from guaranteed.
As Hernández writes: "It is easier to forget a disease that cannot be seen." NTDs primarily affect residents of distant lands. They kill only 80,000 people a year, down from 204,000 in 1990. So why should Americans to bother to look?
Breaking the circle of poverty and disease
The World Health Organization counts 20 diseases as NTDs. Along with Chagas, they include dengue and chikungunya, which cause high fevers and agonizing pain; elephantiasis, which deforms victims' limbs and genitals; onchocerciasis, which causes blindness; schistosomiasis, which can damage the heart, lungs, brain, and genitourinary system; helminths such as roundworm and whipworm, which cause anemia, stunted growth, and cognitive disabilities; and a dozen more. Such ailments often co-occur in the same patient, exacerbating each other's effects and those of illnesses such as malaria.
NTDs may be spread by insects, animals, soil, or tainted water; they may be parasitic, bacterial, viral, or—in the case of snakebite envenoming—non-infectious. What they have in common is their longtime neglect by public health agencies and philanthropies. In part, this reflects their typically low mortality rates. But the biggest factor is undoubtedly their disempowered patient populations.
"These diseases occur in the setting of poverty, and they cause poverty, because of their chronic and debilitating effects," observes Peter Hotez, dean of the National School of Tropical Medicine at Baylor University and co-director of the Texas Children's Hospital for Vaccine Development. And historically, the everyday miseries of impoverished people have seldom been a priority for those who set the global health agenda.
That began to change about 20 years ago, when Hotez and others developed the conceptual framework for NTDs and early proposals for combating them. The WHO released its first roadmap in 2012, targeting 17 NTDs for control, elimination, or eradication by 2020. (Rabies, snakebite, and dengue were added later.) Since then, the number of people at risk for NTDs has fallen by 600 million, and 42 countries have eliminated at least one such disease. Cases of dracunculiasis—known as Guinea worm disease, for the parasite that creates painful blisters in a patient's skin—have dropped from the millions to just 27 in 2020.
Yet the battle is not over, and the COVID-19 pandemic has disrupted prevention and treatment programs around the globe.
A new direction — and longstanding obstacles
The WHO's new roadmap sets even more ambitious goals for 2030. Among them: reducing by 90 percent the number of people requiring treatment for NTDs; eliminating at least one NTD in another 100 countries; and fully eradicating dracunculiasis and yaws, a disfiguring skin infection.
The plan also places an increased focus on "country ownership," relying on nations with high incidence of NTDs to design their own plans based on local expertise. "I was so excited to see that," says Kristina Talbert-Slagle, director of the Yale College Global Health Studies program. "No one is a better expert on how to address these situations than the people who deal with it day by day."
Another fresh approach is what the roadmap calls "cross-cutting" targets. "One of the really cool things about the plan is how much it emphasizes coordination among different sectors of the health system," says Claire Standley, a faculty member at Georgetown University's Center for Global Health Science and Security. "For example, it explicitly takes into account the zoonotic nature of many neglected tropical diseases—the fact that we have to think about animal health as well as human health when we tackle NTDs."
Whether this grand vision can be realized, however, will depend largely on funding—and that, in turn, is a question of political will in the countries most able to provide it. On the upside, the U.S. has ended its Trump-era feud with the WHO. "One thing that's been really encouraging," says Standley, "has been the strong commitment toward global cooperation from the current administration." Even under the previous president, the U.S. remained the single largest contributor to the global health kitty, spending over $100 million annually on NTDs—six times the figure in 2006, when such financing started.
On the downside, America's outlay has remained flat for several years, and the Biden administration has so far not moved to increase it. A "back-of-the-envelope calculation," says Hotez, suggests that the current level of aid could buy medications for the most common NTDs for about 200 million people a year. But the number of people who need treatment, he notes, is at least 750 million.
Up to now, the United Kingdom—long the world's second-most generous health aid donor—has taken up a large portion of the slack. But the UK last month announced deep cuts in its portfolio, eliminating 102 previously supported countries and leaving only 34. "That really concerns me," Hotez says.
The struggle for funds, he notes, is always harder for projects involving NTDs than for those aimed at higher-profile diseases. His lab, which he co-directs with microbiologist Maria Elena Bottazzi, started developing a COVID-19 vaccine soon after the pandemic struck, for example, and is now in Phase 3 trials. The team has been working on vaccines for Chagas, hookworm, and schistosomiasis for much longer, but trials for those potential game-changers lag behind. "We struggle to get the level of resources needed to move quickly," Hotez explains.
Two million reasons to care
One way to prompt a government to open its pocketbook is for voters to clamor for action. A longtime challenge with NTDs, however, has been getting people outside the hardest-hit countries to pay attention.
The reasons to care, global health experts argue, go beyond compassion. "When we have high NTD burden," says Talbert-Slagle, "it can prevent economic growth, prevent innovation, lead to more political instability." That, in turn, can lead to wars and mass migration, affecting economic and political events far beyond an affected country's borders.
Like Hernández's aunt Dora, many people driven out of NTD-wracked regions wind up living elsewhere. And that points to another reason to care about these diseases: Some of your neighbors might have them. In the U.S., up to 14 million people suffer from neglected parasitic infections—including 70,000 with Chagas in California alone.
When Hernández was researching The Kissing Bug, she worried that such statistics would provide ammunition to racists and xenophobes who claim that immigrants "bring disease" or exploit overburdened healthcare systems. (This may help explain some of the stigma around NTDs, which led Tía Dora to hide her condition from most people outside her family.) But as the book makes clear, these infections know no borders; they flourish wherever large numbers of people lack access to resources that most residents of rich countries take for granted.
Indeed, far from gaming U.S. healthcare systems, millions of low-income immigrants can't access them—or must wait until they're sick enough to go to an emergency room. Since Congress changed the rules in 1996, green card holders have to wait five years before they can enroll in Medicaid. Undocumented immigrants can never qualify.
Closing the great divide
Hernández uses a phrase borrowed from global health crusader Paul Farmer to describe this access gap: "the great epi divide." On one side, she explains, "people will die from cancer, from diabetes, from chronic illnesses later in life. On the other side of the epidemiological divide, people are dying because they can't get to the doctor, or they can't get medication. They don't have a hospital anywhere near them. When I read Dr. Farmer's work, I realized how much that applied to neglected diseases as well."
When it comes to Chagas disease, she says, the epi divide is embodied in the lack of a federal mandate for prenatal or newborn screening. Each year, according to the Centers for Disease Control and Prevention, up to 300 babies in the U.S. are born with Chagas, which can be passed from the mother in utero. The disease can be cured with medication if treated in infancy. (It can also be cured in adults in the acute stage, but is seldom detected in time.) Yet the CDC does not require screening for Chagas—even though newborns are tested for 15 diseases that are less common. According to one study, it would be 10 times cheaper to screen and treat babies and their mothers than to cover the costs related to the illness in later years. Few states make the effort.
The gap that enables NTDs to persist, Hernández argues, is the same one that has led to COVID-19 death rates in Black and Latinx communities that are double those elsewhere in America. To close it, she suggests, caring is not enough.
"When I was working on my book," she says, "I thought about HIV in the '80s, when it had so much stigma that no one wanted to talk about it. Then activists stepped up and changed the conversation. I thought a lot about breast cancer, which was stigmatized for years, until people stepped forward and started speaking out. I thought about Lyme disease. And it wasn't only patients—it was also allies, right? The same thing needs to happen with neglected diseases around the world. Allies need to step up and make demands on policymakers. We need to make some noise."
Announcing "The Future of Science in America: The Election Issue"
As reviewed in The Washington Post, "Tomorrow's challenges in science and politics: Magazine offers in-depth takes on these U.S. issues":
"Is it time for a new way to help make adults more science-literate? What should the next president know about science? Could science help strengthen American democracy? "The Future of Science in America: The Election Issue" has answers. The free, online magazine is packed with interesting takes on how science can serve the common good. And just in time. This year has challenged leaders, researchers and the public with thorny scientific questions, from the coronavirus pandemic to widespread misinformation on scientific issues. The magazine is a collaboration of the Aspen Institute, a think tank that brings together a variety of public figures and private individuals to tackle thorny social issues, the digital science magazine Leapsmag and GOOD, a social impact company. It's packed with 15 in-depth articles about science with a view toward our campaign year."
The Future of Science in America: The Election Issue offers wide-ranging perspectives on challenges and opportunities for science as we elect our next national and local leaders. The fast-striking COVID-19 pandemic and the more slowly moving pandemic of climate change have brought into sharp focus how reliant we will be on science and public policy to work together to rescue us from crisis. Doing so will require cooperation between both political parties, as well as significant public trust in science as a beacon to light the path forward.
In spite of its unfortunate emergence as a flash point between two warring parties, we believe that science is the driving force for universal progress. No endeavor is more noble than the quest to rigorously understand our world and apply that knowledge to further human flourishing. This magazine aspires to promote roadmaps for science as a tool for health, a vehicle for progress, and a unifier of our nation.
This special issue is a collaboration among LeapsMag, the Aspen Institute Science & Society Program, and GOOD, with support from the Gordon and Betty Moore Foundation and the Rita Allen Foundation.
It is available as a free, beautifully designed digital magazine for both desktop and mobile.
TABLE OF CONTENTS:
- SCIENTISTS:
Award-Winning Scientists Offer Advice to the Next President of the United States - PUBLIC OPINION:
National Survey Reveals Americans' Most Important Scientific Priorities - GOVERNMENT:
The Nation's Science and Health Agencies Face a Credibility Crisis: Can Their Reputations Be Restored? - TELEVISION:
To Make Science Engaging, We Need a Sesame Street for Adults - IMMIGRATION:
Immigrant Scientists—and America's Edge—Face a Moment of Truth This Election - RACIAL JUSTICE:
Democratize the White Coat by Honoring Black, Indigenous, and People of Color in Science - EDUCATION:
I'm a Black, Genderqueer Medical Student: Here's My Hard-Won Wisdom for Students and Educational Institutions - TECHNOLOGY:
"Deep Fake" Video Technology Is Advancing Faster Than Our Policies Can Keep Up - VOTERS:
Mind the (Vote) Gap: Can We Get More STEM Students to the Polls? - EXPERTS:
Who Qualifies as an "Expert" and How Can We Decide Who Is Trustworthy? - SOCIAL MEDIA:
Why Your Brain Falls for Misinformation—And How to Avoid It - YOUTH:
Youth Climate Activists Expand Their Focus and Collaborate to Get Out the Vote - SUPREME COURT:
Abortions Before Fetal Viability Are Legal: Might Science and a Change on the Supreme Court Undermine That? - NAVAJO NATION:
An Environmental Scientist and an Educator Highlight Navajo Efforts to Balance Tradition with Scientific Priorities - CIVIC SCIENCE:
Want to Strengthen American Democracy? The Science of Collaboration Can Help
Kira Peikoff was the editor-in-chief of Leaps.org from 2017 to 2021. As a journalist, her work has appeared in The New York Times, Newsweek, Nautilus, Popular Mechanics, The New York Academy of Sciences, and other outlets. She is also the author of four suspense novels that explore controversial issues arising from scientific innovation: Living Proof, No Time to Die, Die Again Tomorrow, and Mother Knows Best. Peikoff holds a B.A. in Journalism from New York University and an M.S. in Bioethics from Columbia University. She lives in New Jersey with her husband and two young sons. Follow her on Twitter @KiraPeikoff.
Scientists Envision a Universal Coronavirus Vaccine
With several companies progressing through Phase III clinical trials, the much-awaited coronavirus vaccines may finally become reality within a few months.
But some scientists question whether these vaccines will produce a strong and long-lasting immunity, especially if they aren't efficient at mobilizing T-cells, the body's defense soldiers.
"When I look at those vaccines there are pitfalls in every one of them," says Deborah Fuller, professor of microbiology at the Washington University School of Medicine. "Some may induce only transient antibodies, some may not be very good at inducing T-cell responses, and others may not immunize the elderly very well."
Generally, vaccines work by introducing an antigen into the body—either a dead or attenuated pathogen that can't replicate, or parts of the pathogen or its proteins, which the body will recognize as foreign. The pathogens or its parts are usually discovered by cells that chew up the intruders and present them to the immune system fighters, B- and T-cells—like a trespasser's mug shot to the police. In response, B-cells make antibodies to neutralize the virus, and a specialized "crew" called memory B-cells will remember the antigen. Meanwhile, an army of various T-cells attacks the pathogens as well as the cells these pathogens already infected. Special helper T-cells help stimulate B-cells to secrete antibodies and activate cytotoxic T-cells that release chemicals called inflammatory cytokines that kill pathogens and cells they infected.
"Each of these components of the immune system are important and orchestrated to talk to each other," says professor Larry Corey, who studies vaccines and infectious disease at Fred Hutch, a non-profit scientific research organization. "They optimize the assault of the human immune system on the complexity of the viral, bacterial, fungal and parasitic infections that live on our planet, to which we get exposed."
Despite their variety, coronaviruses share certain common proteins and other structural elements, Fuller explains, which the immune system can be trained to identify.
The current frontrunner vaccines aim to train our body to generate a sufficient amount of antibodies to neutralize the virus by shutting off its spike proteins before it enters our cells and begins to replicate. But a truly robust vaccine should also engender a strong response from T-cells, Fuller believes.
"Everyone focuses on the antibodies which block the virus, but it's not always 100 percent effective," she explains. "For example, if there are not enough titers or the antibody starts to wane, and the virus does get into the cells, the cells will become infected. At that point, the body needs to mount a robust T-cytotoxic response. The T-cells should find and recognize cells infected with the virus and eliminate these cells, and the virus with them."
Some of the frontrunner vaccine makers including Moderna, AstraZeneca and CanSino reported that they observed T-cell responses in their trials. Another company, BioNTech, based in Germany, also reported that their vaccine produced T-cell responses.
Fuller and her team are working on their own version of a coronavirus vaccine. In their recent study, the team managed to trigger a strong antibody and T-cell response in mice and primates. Moreover, the aging animals also produced a robust response, which would be important for the human elderly population.
But Fuller's team wants to engage T-cells further. She wants to try training T-cells to recognize not only SARV-CoV-2, but a range of different coronaviruses. Wild hosts, such as bats, carry many different types of coronaviruses, which may spill over onto humans, just like SARS, MERS and SARV-CoV-2 have. There are also four coronaviruses already endemic to humans. Cryptically named 229E, NL63, OC43, and HKU1, they were identified in the 1960s. And while they cause common colds and aren't considered particularly dangerous, the next coronavirus that jumps species may prove deadlier than the previous ones.
Despite their variety, coronaviruses share certain common proteins and other structural elements, Fuller explains, which the immune system can be trained to identify. "T-cells can recognize these shared sequences across multiple different types of coronaviruses," she explains, "so we have this vision for a universal coronavirus vaccine."
Paul Offit at Children's Hospitals in Philadelphia, who specializes in infectious diseases and vaccines, thinks it's a far shot at the moment. "I don't see that as something that is likely to happen, certainly not very soon," he says, adding that a universal flu vaccine has been tried for decades but is not available yet. We still don't know how the current frontrunner vaccines will perform. And until we know how efficient they are, wearing masks and keeping social distance are still important, he notes.
Corey says that while the universal coronavirus vaccine is not impossible, it is certainly not an easy feat. "It is a reasonably scientific hypothesis," he says, but one big challenge is that there are still many unknown coronaviruses so anticipating their structural elements is difficult. The structure of new viruses, particularly the recombinant ones that leap from wild hosts and carry bits and pieces of animal and human genetic material, can be hard to predict. "So whether you can make a vaccine that has universal T-cells to every coronavirus is also difficult to predict," Corey says. But, he adds, "I'm not being negative. I'm just saying that it's a formidable task."
Fuller is certainly up to the task and thinks it's worth the effort. "T-cells can cross-recognize different viruses within the same family," she says, so increasing their abilities to home in on a broader range of coronaviruses would help prevent future pandemics. "If that works, you're just going to take one [vaccine] and you'll have lifetime immunity," she says. "Not just against this coronavirus, but any future pandemic by a coronavirus."
Lina Zeldovich has written about science, medicine and technology for Popular Science, Smithsonian, National Geographic, Scientific American, Reader’s Digest, the New York Times and other major national and international publications. A Columbia J-School alumna, she has won several awards for her stories, including the ASJA Crisis Coverage Award for Covid reporting, and has been a contributing editor at Nautilus Magazine. In 2021, Zeldovich released her first book, The Other Dark Matter, published by the University of Chicago Press, about the science and business of turning waste into wealth and health. You can find her on http://linazeldovich.com/ and @linazeldovich.