COVID cases are on the rise again in many countries. And this time, the SARS-CoV-2 virus has company. In the United States, Europe and Asia, the flu virus and a third dangerous pathogen—the respiratory syncytial virus—are surging at the same time as the novel-coronavirus.
It’s a “tripledemic,” to use an admittedly non-scientific term. And it’s a harbinger of our pathogenic future. As we chop down more forests, releasing more and more animal viruses into the human population—and as disinformation floods social media, driving vaccine-skepticism to startling highs—overlapping viral outbreaks could become the norm.
Add another monkeypox or bird flu outbreak, and we might even experience a “quadrupledemic.” Besides potentially overwhelming health systems, the simultaneous outbreaks come with another troubling risk. Research indicates they might actually make each other worse.
Epidemiologists expect viral infections to spike in the winter months. People are traveling for various holidays, dragging their viruses along with them and exposing everyone else along the way. Cold weather drives people indoors, where they share air, spittle and any pathogens riding on the air and spittle.
Hence the seasonal flu outbreaks we usually see in the winter. COVID has also developed a seasonal pattern for the same reasons. So it came as no surprise that COVID cases began ticking upward in the U.S., Europe and Japan in recent weeks. There’s an alarming surge in novel-coronavirus infections in China, too—but there are unique reasons for that.
COVID and flu were about to begin their usual winter rampage when the respiratory syncytial virus showed up in a big way, too. At the peak of the RSV outbreak in the U.S. in mid-November, the Centers for Disease Control and Prevention logged a case-rate five times as high as last year.
The European division of the World Health Organization summed up the crisis in a Dec. 1 statement. “The region is currently experiencing increasing circulation of influenza and RSV. Together with COVID-19, these viruses are expected to have a high impact on our health services and populations this winter.”
RSV usually causes mild, cold-like symptoms—and most people recover quickly. In infants and seniors, however, RSV can be deadly. It’s the leading cause of pneumonia in newborns. Besides the cumulative strain that RSV and other viruses can place on hospitals when they surge simultaneously, there are signs that the flu and COVID are making RSV more dangerous—and vice versa.
James Lawler, an infectious disease expert at the University of Nebraska Medical Center, pieced together the clues. “We had relatively normal levels of flu and RSV activity last year, but with relatively normal … hospitalization [or] death consequences,” he told The Daily Beast. “This year, we have somewhat higher than normal flu and RSV activity—at least earlier for flu—and much higher rates of hospitalization in young people.”
Last year’s winter surge in COVID, driven by the Omicron variant, may have weakened millions of people who wouldn’t normally be at high risk for flu and RSV. “COVID results in long-lasting disruption in immune function and health effects in people well after acute infection,” Lawler explained.
It’s okay to be skeptical of possible interplay between the three viruses. “It’s difficult to say we have hard evidence,” Lawler stressed. But he noted a compelling bit of circumstantial evidence. “Countries that have done better controlling COVID—South Korea, Japan, Taiwan—are not experiencing increased levels of hospitalization from flu or RSV this year.” Sure, the rate of flu and RSV is high in Japan, but the severity is normal—and most people are recovering at home.
Research could eventually prove, or disprove, that the immune effects of one viral infection make a separate and different infection more likely or worse. While we wait for the science to catch up, we’re walking on epidemiological thin ice. Humanity seems determined to expose itself to more and more viruses. At same time, it’s equally determined not to protect itself from the effects of these pathogens.
Many of the worst human viruses didn’t start in humans. They’re animal viruses that made the leap to homo sapiens after prolonged exposure. Monkeypox was endemic in monkey and rodent populations in West and Central Africa and only became a human problem with the accelerating destruction of the African rainforest in the 1970s. COVID appears to have jumped from pangolins (a kind of scaly anteater) or bats to people, possibly at a wildlife market in Wuhan, China. Bird flu, which occasionally rages through human populations, is—as its name implies—a bird virus.
The more forests we chop down, the more wild animals we trade as pets or for food and the more chickens we cram into industrial farms, the more viruses we come into contact with—and the greater the risk of animal-to-people transmission. A process scientists call “zoonosis.”
Barring a profound shift in the way people build and eat, zoonosis is only going to get worse. “Larger human population overall—increases the number of human-animal contact events,” Tony Moody, a professor of immunology at the Duke Human Vaccine Institute, told The Daily Beast. There’s also a “need for increased food production because of the increased population, so increasing domestic animal contacts.”
We could protect ourselves from the worst outcomes with vaccines. But the trends on that front are equally discouraging. As trust in science wanes and more people get their “news” from conspiracy theorists on social media, vaccine uptake is beginning to suffer.
A quarter of Americans still refuse to get any COVID vaccines. Uptake of the latest booster is catastrophically low in the U.S. More people didn’t bother getting their flu jabs this year, as well. Vulnerable communities eagerly embraced the monkeypox vaccine, thank goodness, but rejection of the tried-and-true polio vaccine in a handful of New York counties led to a rare—and frankly terrifying—surge in polio cases this summer. Polio, once widespread, can cause paralysis in a small number of cases.
Zoonosis and vaccine-hesitancy are the twin forces of the overlapping viral outbreaks that could define our epidemiological future as a species. It’s hard to imagine any point in the foreseeable future when humanity won’t be grappling with at least one major viral outbreak, because it’s hard to imagine humanity swiftly ending deforestation and quickly reversing the flow of disinformation on the internet.
Preventable outbreaks are here to stay. From probably more than one major virus at a time.