“Just a few years ago, many of us in the global health policy community were thrilled at the prospect of eliminating catastrophic infectious and tropical diseases,” Peter Hotez writes in his new book, “Preventing the Next Pandemic” (Johns Hopkins). He dates this high point of optimism to the start of 2015, when the success of vaccination campaigns had become dramatically evident. Polio, once endemic in more than a hundred countries, had been limited to three—Afghanistan, Nigeria, and Pakistan. Measles deaths were down by eighty per cent, from half a million children worldwide in 2000 to a fifth of that number. Vaccination campaigns achieved similar reductions in mortality with diphtheria, whooping cough, tetanus, and a type of bacterial meningitis.
As the world nervously watches the rollout of the various COVID-19 vaccines and surveys the human and economic cost of the pandemic, this period of optimism is hard to imagine. Yet Hotez, a pediatrician and a specialist in tropical infectious diseases at Baylor College of Medicine who co-directs a vaccine-development center at the Texas Children’s Hospital, shows that pandemics had been rebounding well before the first COVID-19 cases emerged in Wuhan. His book draws lessons from the field of tropical infectious diseases, and also from his international work as a science envoy—a position created jointly by the State Department and the White House—during Barack Obama’s Presidency. Hotez is perhaps uniquely positioned to expound a broad vision that marries science with geopolitics. (In the past year, he has been a prominent TV expert on the pandemic.) We learn not only about familiar scourges such as polio and diphtheria but also about a host of so-called neglected tropical diseases, including dengue, leishmaniasis, schistosomiasis, and Chagas. He melds an account of their biology with documentation of the social and political factors that enable them to spread, and passionately insists that we cannot prevent pandemics in isolation from wider global currents. He identifies a cluster of non-medical drivers of deadly outbreaks—war, political instability, human migration, poverty, urbanization, anti-science and nationalist sentiment, and climate change—and maintains that advances in biomedicine must be accompanied by concerted action on these geopolitical matters.
The message comes at a time when the Biden Administration has done much both to stem the pandemic in the United States and to reverse the deleterious approach of the Trump White House. Biden has facilitated widespread distribution of vaccines, recently announcing that all adult Americans would be eligible for shots by the beginning of May, and he has instituted public-health measures, such as mandatory masks on trains and planes, that should have been in place a year ago. He has reaffirmed U.S. membership in the World Health Organization, appointing Anthony Fauci as the head delegate. And the Administration has withdrawn numerous budget-cut requests that Trump sent to Congress, including one that would have cancelled four billion dollars of funding for Gavi, a public-private partnership that provides vaccinations in low-income countries.
As welcome as all this is, any hope of containing future outbreaks will require tackling deeply rooted global problems. President Biden’s belief in the power of revitalized American diplomacy will be tested not only in such areas as trade agreements and nuclear-arms control but also in the fight against epidemics that occur far from American soil.
War and Pestilence ride together as two of the Four Horsemen of the Apocalypse, and there is no shortage of historical precedent to demonstrate the aptness of the allegory. The great influenza pandemic that began in 1918 was propelled, in part, by troop movements and population shifts at the end of the First World War. Both the First and the Second World Wars produced typhus epidemics. Armed conflicts cause malnutrition, poor pest control, and sanitation problems; even the soil often becomes contaminated. Medical facilities are destroyed; doctors and nurses, diverted to combat duty, are unable to provide care, and vaccination and other mass-treatment programs usually falter.
The first two decades of this century have furnished many fresh examples. The ongoing conflict in Yemen has produced the largest cholera outbreak in history, which has infected two and a half million people since it began, in 2016. Wars in Syria and Iraq led to a resurgence of measles and polio. The collapse of insect-control programs sparked the spread of cutaneous leishmaniasis, a parasitic disease that results in disfiguring skin ulcers. Known as “Baghdad boil” or “Aleppo evil,” it is transmitted through the bite of blood-feeding sand flies, which flourish in uncollected garbage. By 2016, the destruction of infrastructure in conflict zones had brought about a tenfold increase in such cases in Syria, some two hundred and seventy thousand a year, with another hundred thousand a year recorded in Iraq.
Hotez writes that wars in the Middle East have made the region “a new global hot zone of emerging and neglected tropical diseases.” The news elsewhere is scarcely better. During conflicts in the Democratic Republic of the Congo, the Central African Republic, and South Sudan, measles returned, along with kala-azar, another type of leishmaniasis, which attacks internal organs and is frequently fatal. The 2018 Ebola outbreak in the Democratic Republic of the Congo left more than two thousand dead. In northeastern Nigeria, attacks by Boko Haram have destroyed as much as three-quarters of the infrastructure required for vaccinations, and there has been a corresponding rise in cases of polio, measles, whooping cough, bacterial meningitis, and yellow fever. A 2019 study cited by Hotez found that a child born within six miles of the conflict zone is half as likely to receive any vaccine as other Nigerian children.
Even in the absence of war, political instability can produce comparable results. Hotez discusses Venezuela, which, under Nicolás Maduro, has suffered a level of economic collapse and social chaos that has led to the unravelling of the country’s health-care system. Measles had been eradicated, but it reëmerged in 2017. As public-hygiene infrastructure has deteriorated, there has been a spread of schistosomiasis, a disease transmitted by freshwater snails and typically contracted when people bathe or wash laundry in infested rivers. (The snails are vectors for a microscopic parasite whose eggs end up in the liver and gut, causing inflammation and tissue damage.) A breakdown in pest-control measures fuelled a rise in mosquito-borne illnesses, including the Zika virus, chikungunya, and dengue. Of course, once infectious diseases take hold in one country they easily spread to others. A diphtheria outbreak in Venezuela’s illegal mining camps crossed the border into Brazil. A flareup of dengue recently reported on the Portuguese island of Madeira, off the coast of Africa, may well have originated in Venezuela.
It is estimated that ten per cent of Venezuela’s population—more than three million people—has emigrated, joining the ranks of the world’s refugees. In war-torn countries, people flee at even greater rates, whether within the country or outside it. As Hotez points out, refugees often lack adequate food and shelter, as well as access to health care. In makeshift camps, malnutrition, crowding, and lack of vaccination or medical care increase exposure to insects and microbes. Sexual violence spreads viruses like H.I.V.
As refugees from African and Middle Eastern wars have fled to Europe, diseases long thought eliminated have begun reappearing: chikungunya and dengue have surfaced in Italy, Spain, and Portugal; malaria in Greece and Italy. The island of Corsica has experienced its first-ever cases of schistosomiasis. Hotez is rightly careful not to attribute these infections strictly to the migration of refugees, noting that warming temperatures in Southern Europe, owing to climate change, and recessions in Italy and Greece may also be factors. Another factor is that refugees tend to flee to urban areas: in Syria, thousands have crowded into slums in Aleppo; in the Democratic Republic of the Congo, Kinshasa has become a major hub.
Migration aside, dense urbanization leads to the spread of infectious disease, too, because burgeoning populations quickly outstrip sanitation infrastructure. The coming decade, Hotez writes, will witness “the unprecedented creation of new megacities,” heavily populated urban centers with at least ten million inhabitants. Some forty megacities are predicted to emerge by 2030, many of them in low-income nations of Africa, Asia, and Latin America. Hotez paints an alarming picture of megacities incapable of providing safe water and adequate sanitation, leading to typhoid fever and cholera, as well as leptospirosis, which festers in the kidneys of urban rats and dogs and can be passed to people through contaminated drinking water.
To complete this dystopian vision, Hotez highlights how climate change will further inflame contagious disease. Unprecedented heat waves in the Middle East have produced droughts that create food insecurity and fierce competition for water supplies, driving rural populations to already overcrowded urban centers. Warming temperatures also shift insect ecosystems. West Nile virus is now common in Southern Europe. Mosquito-transmitted viruses have swept across South and Central America into the Caribbean and then into Texas and Florida. Hotez cites a recent study, led by the epidemiologist Simon Hay, which predicts that by 2050 dengue infections will have made further inroads into the United States.
Most of Hotez’s infection-boosting factors have clear physical manifestations. The exception, “anti-science and nationalism,” is in many ways the most exasperating. How can it be that we are threatened not only by insects and filth and the frailties of our own bodies but also by something as intangible as our beliefs? For Hotez, the rise of anti-science ideology—most particularly, the anti-vaccine movement—is highly personal. His previous book centered on his daughter Rachel, now in her twenties, and bore the title “Vaccines Did Not Cause Rachel’s Autism” (2018). He now updates us on the results of his efforts to dispel claims that vaccines cause autism-spectrum disorders. Noting that these claims were producing “steep declines in the numbers of kids vaccinated,” he attempted to publicize the “massive evidence refuting any link, or even plausibility, given what we have learned about the genetics, natural history, and developmental pathways of autism.” For his pains, he was pursued online by anti-vaxxers who propagate specious accusations that he personally profited from vaccines.
Hotez observes that there are some five hundred Web sites spreading anti-vaccine misinformation, whose assertions are further disseminated on social media and on e-commerce platforms. “The largest e-commerce platform of them all, Amazon, is now the most active promoter of fake anti-vaccine books,” he writes. “Go to Amazon books, click on ‘Health, Fitness, and Dieting’ on the scroll down menu at the left, and then click on ‘Vaccinations’ to see how legitimate books on vaccines are pushed behind by the fake ones.” He finds that the online sensorium is so clogged with misinformation that it is now hard for concerned parents to find trustworthy data: “Serious and meaningful information regarding this topic resembles a lost message in a bottle floating aimlessly in the Atlantic Ocean.” Action is urgently needed; measles cases are spiking in Europe, and the W.H.O. has identified “vaccine hesitancy” as one of the world’s most urgent health issues.
Hotez goes on to survey the political power of the anti-vaccine camp. In the United States and Europe, anti-vaxxers have joined forces with populist and libertarian movements, and American groups aligned with the Tea Party invoke “medical freedom,” “health freedom,” or “choice” to justify withholding vaccines from children. Anti-vaxxer political-action committees lobby state legislatures to allow parents to opt out of school vaccine requirements. Under the Trump Administration, more than eight hundred and fifty thousand dollars in loans from the federal Paycheck Protection Program went to five major anti-vaccine groups—including such deceptively named entities as the National Vaccine Information Center and Children’s Health Defense. In January, when COVID-19 vaccines were being administered at Dodger Stadium, in Los Angeles, far-right and anti-vaxxer groups blocked the entrance to the site, forcing the police to temporarily shut it down.
Hotez examines how this obscurantist ideology circulates, and offers three case studies. Starting in around 2008, the Somali immigrant community in Minneapolis was offered “town hall meetings” touting the vaccine-autism link, and by 2017 the same community was in the throes of a measles outbreak. In 2019, the Orthodox Jewish community in New York was treated to ads with “fake Holocaust imagery, including yellow stars, to compare vaccines to the Holocaust.” The result was “one of America’s worst measles epidemics in decades.” The third target was the African-American community in Harlem, which received propaganda in which vaccines were compared to the infamous Tuskegee syphilis study. Probing the motivation of the groups that spread such lies, Hotez follows the money and concludes that the perpetrators are often just “monetizing the Internet by selling phony autism therapies (including bleach enemas) and nutritional supplements, fake books, or advertising.”
His suggested remedy is to pressure social-media and e-commerce sites to take down misleading content. This is already happening, to some extent. In December, Facebook at last banned misinformation about the COVID vaccines—a rule that was expanded, in February, to cover vaccines of any kind—and it has since suspended groups like the National Vaccine Information Center and Stop Mandatory Vaccination. Nonetheless, anti-vaccine accounts on social media continue to flourish, having gained more than ten million new followers since 2019.