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."
Your Privacy vs. the Public's Health: High-Tech Tracking to Fight COVID-19 Evokes Orwell
The COVID-19 pandemic has placed public health and personal privacy on a collision course, as smartphone technology has completely rewritten the book on contact tracing.
It's not surprising that an autocratic regime like China would adopt such measures, but democracies such as Israel have taken a similar path.
The gold standard – patient interviews and detective work – had been in place for more than a century. It's been all but replaced by GPS data in smartphones, which allows contact tracing to occur not only virtually in real time, but with vastly more precision.
China has gone the furthest in using such tech to monitor and prevent the spread of the coronavirus. It developed an app called Health Code to determine which of its citizens are infected or at risk of becoming infected. It has assigned each individual a color code – red, yellow or green – and restricts their movement depending on their assignment. It has also leveraged its millions of public video cameras in conjunction with facial recognition tech to identify people in public who are not wearing masks.
It's not surprising that an autocratic regime like China would adopt such measures, but democracies such as Israel have taken a similar path. The national security agency Shin Bet this week began analyzing all personal cellphone data under emergency measures approved by the government. It texts individuals when it's determined they had been in contact with someone who had the coronavirus. In Spain and China, police have sent drones aloft searching for people violating stay-at-home orders. Commands to disperse can be issued through audio systems built into the aircraft. In the U.S., efforts are underway to lift federal restrictions on drones so that police can use them to prevent people from gathering.
The chief executive of a drone manufacturer in the U.S. aptly summed up the situation in an interview with the Financial Times: "It seems a little Orwellian, but this could save lives."
Epidemics and how they're surveilled often pose thorny dilemmas, according to Craig Klugman, a bioethicist and professor of health sciences at DePaul University in Chicago. "There's always a moral issue to contact tracing," he said, adding that the issue doesn't change by nation, only in the way it's resolved.
"Once certain privacy barriers have been breached, it can be difficult to roll them back again."
In China, there's little to no expectation for privacy, so their decision to take the most extreme measures makes sense to Klugman. "In China, the community comes first. In the U.S., individual rights come first," he said.
As the U.S. has scrambled to develop testing kits and manufacture ventilators to identify potential patients and treat them, individual rights have mostly not received any scrutiny. However, that could change in the coming weeks.
The American approach is also leaning toward using smartphone apps, but in a way that may preserve the privacy of users. Researchers at MIT have released a prototype known as Private Kit: Safe Paths. Patients diagnosed with the coronavirus can use the app to disclose their location trail for the prior 28 days to other users without releasing their specific identity. They also have the option of sharing the data with public health officials. But such an app would only be effective if there is a significant number of users.
Singapore is offering a similar app to its citizens known as TraceTogether, which uses both GPS and Bluetooth pings among users to trace potential encounters. It's being offered on a voluntary basis.
The Electronic Frontier Foundation, the leading nonprofit organization defending civil liberties in the digital world, said it is monitoring how these apps are developed and deployed. "Governments around the world are demanding new dragnet location surveillance powers to contain the COVID-19 outbreak," it said in a statement. "But before the public allows their governments to implement such systems, governments must explain to the public how these systems would be effective in stopping the spread of COVID-19. There's no questioning the need for far-reaching public health measures to meet this urgent challenge, but those measures must be scientifically rigorous, and based on the expertise of public health professionals."
Andrew Geronimo, director of the intellectual property venture clinic at the Case Western University School of Law, said that the U.S. government is currently in talks with Facebook, Google and other tech companies about using deidentified location data from smartphones to better monitor the progress of the outbreak. He was hesitant to endorse such a step.
"These companies may say that all of this data is anonymized," he said, "but studies have shown that it is difficult to fully anonymize data sets that contain so much information about us."
Beyond the technical issues, social attitudes may mount another challenge. Epic events such as 9/11 tend to loosen vigilance toward protecting privacy, according to Klugman and Geronimo. And as more people are sickened and hospitalized in the U.S. with COVID-19, Klugman believes more Americans will be willing to allow themselves to be tracked. "If that happens, there needs to be a time limitation," he said.
However, even if time limits are put in place, Geronimo believes it would lead to an even greater rollback of privacy during the next crisis.
"Once certain privacy barriers have been breached, it can be difficult to roll them back again," he warned. "And the prior incidents could always be used as a precedent – or as proof of concept."
Stem Cell Therapy for COVID-19 Is Gaining Steam in China, But Some Skeptical Scientists Urge Caution
Over the past two months, China's frantic search for an effective COVID-19 treatment has seen doctors trying everything from influenza drugs to traditional herbal remedies and even acupuncture, in a bid to help patients suffering from coronavirus-induced pneumonia.
"This treatment is particularly aimed at older patients who are seriously ill. These kinds of patients are in the danger zone."
Since mid February, one approach that has gained increasing traction is stem cell therapies, treatments that have often been viewed as a potential panacea by desperate patients suffering from degenerative incurable conditions ranging from Parkinson's to ALS. In many of these diseases, reality has yet to match the hype.
In COVID-19, there are hopes it might, though some experts are warning not to count on it. At Beijing's YouAn Hospital, doctors have been treating patients at various stages of the illness with intravenous infusions of so-called mesenchymal stem cells taken from umbilical cord tissue, as part of an ongoing clinical trial since January 21. The outcomes of the initial seven patients – published last month – appeared promising and the trial has since been expanded to 31 patients according to Dr. Kunlin Jin, a researcher at University of North Texas Health Science Center who is collaborating with the doctors in Beijing.
"Sixteen of these patients had mild symptoms, eight are severe, and seven are critically severe," Jin told leapsmag. "But all patients have shown improvements in lung function following the treatment, based on CT scans -- most of them in the first three days and seven have now been completely discharged from hospital. This treatment is particularly aimed at older patients who are seriously ill. These kinds of patients are in the danger zone; it's essential that they receive treatment, but right now we have nothing for most of them. No drugs or anything."
The apparent success of the very small Beijing trial has since led to a nationwide initiative to fast-track stem cell therapies for COVID-19. Across China, there are currently 36 clinical trials intending to use mesenchymal stem cells to treat COVID-19 patients that are either in the planning or recruiting phases. The Chinese Medical Association has now issued guidelines to standardize stem cell treatment for COVID-19, while Zhang Xinmin, an official in China's Ministry of Science and Technology, revealed in a press conference last week that a stem cell-based drug has been approved for clinical trials.
The thinking behind why stem cells could be a fast-acting and effective treatment is due to the nature of COVID-19. The thousands of fatalities worldwide are not from the virus directly, but from a dysfunctional immune response to the infection. Patients die because their respiratory systems become overwhelmed by a storm of inflammatory molecules called cytokines, causing lung damage and failure. However, studies in mice have long shown that stem cells have anti-inflammatory properties with the ability to switch off such cytokine storms, reducing such virus-induced lung injuries.
"There has been an enormous amount of hype about these cells, and there is scant scientific evidence that they have any therapeutic effect in any situation. "
"The therapy can inhibit the overactivation of the immune system and promote repair by improving the pulmonary microenvironment and improve lung function," explained Wei Hou, one of the doctors conducting the trial at YouAn Hospital.
However not everyone is convinced, citing the small number of patients treated to date, and potential risks from such therapy. "We just don't know enough to believe that stem cells might be helpful with COVID-19," said Paul Knoepfler, professor of cell biology at UC Davis. "The new stem cell studies are too small and lack controls, making it impossible to come to any solid conclusions. The chance of benefit is low based on the little we know so far and there are going to be risks that are hard to pin down. For instance, what if a stem cell infusion impairs some kind of needed immune response?"
Other scientists are even more skeptical. "I am concerned about all treatments that use mesenchymal stem cells," warned Jeanne Loring, the Director of the Center for Regenerative Medicine at Scripps Research in La Jolla, Calif. "There has been an enormous amount of hype about these cells, and there is scant scientific evidence that they have any therapeutic effect in any situation. Typically, these treatments are offered to people who have diseases without cures. I'm certain that there will be evidence-based treatments for COVID19, but I understand that they are not yet available, people are desperate, and they will try anything. I hope the sick are not taken advantage of because of their desperation."
Despite such concerns, the steadily rising death toll from COVID-19 means other nations are preparing to proceed with their own clinical trials of mesenchymal stem cells. Jin said he has been contacted by researchers and clinicians around the world seeking information on how to conduct their own trials, with the University of Cambridge's Stem Cell Institute in the U.K. reportedly looking to initiate a trial.
The scale of the global emergency has seen governments repeatedly calling on the corporate world to invest in the search for a cure, and the Australian company Mesoblast – a global leader in cell-based therapies for a range of diseases – are expecting to receive the green light to initiate clinical trials of their own stem cell based product against COVID-19.
"We're talking to at least three major governments," said Silviu Itescu, CEO and Managing Director of Mesoblast. "We are working with groups in Australia, the U.S. and the U.K., and I expect there'll be trials starting imminently in all those jurisdictions."
Itescu is bullish that the therapy has a good chance of proving effective, as it recently successfully completed Phase III trials for severe steroid-refractory acute graft versus host disease (GVHD) – a condition which leads to a very similar disease profile to COVID-19.
"The exact same cytokine profile is occurring in the lungs of COVID-19 infected patients as in GVHD which is destructive to the local lung environment," he said. "If our cells are able to target that in GVHD, they ought to be able to switch off the cytokine response in COVID lung disease as well."
"What we should be focusing on now is not the possible boost to the stem cell field, but rather doing rigorous science to test whether stem cells can help COVID-19 patients."
Jin is hopeful that if the imminent trials yield successful results, the U.S. FDA could fast-track mesenchymal stem cells as an approved emergency therapy for COVID-19. However, Knoepfler cautions that there is a need for far more concrete and widespread proof of the benefit before regulatory bodies start ushering through the green light.
"What we should be focusing on now is not the possible boost to the stem cell field, but rather doing rigorous science to test whether stem cells can help COVID-19 patients," he said. "During a pandemic, it's reasonable to do some testing of unproven interventions like stem cells in small studies, but results from them should be discussed in a sober, conservative manner until there is more evidence."