REVENGE OF THE PATHOGENS

THE WORLD SEEMS TO BE ENTERING A NEW, DEADLY ERA OF HEALTH THREATS FROM INFECTIOUS DISEASES-OLD ONES WE THOUGHT WE'D WIPED OUT, AND NEW ONES ON THE RISE 

- DAVID H. FREEDMAN

FROM OLD TO NEW

Children with tuberculosis in London in 1932

AS THE WORLD GRAPPLES WITH THE REALITY OF living with COVID-19, a rogue's gallery of deadly pathogens seems to have stepped up the attack. Monkeypox, a close relation of smallpox, is officially a public health emergency worldwide. The current outbreak the first large one ever outside of Africa has spread globally to more than 45,000 people, including more than 16,000 confirmed cases in the U.S. And polio, a disease routinely referred to as "eradicated," is circulating in and around New York City and London, bringing with it the irreversible paralysis that strikes about one of 200 people infected with the disease.

These two headline-grabbing afflictions are only the most visible elements in a spate of new outbreaks. The world seems to be entering a new, deadly era of health threats from infectious diseases-old ones we thought we'd wiped out, and new ones on the rise. "It feels like COVID-19 has opened up a Pandora's box of infectious disease surprises," says Michael Osterholm, director of the Center for Infectious Disease Research and Policy at the University of Minnesota. "What's next?"

an illustration of the coronavirus that causes COVID-19.

Why this deadly trend is happening at this particular moment is something of a mystery. The rise in anti-vax sentiment and the politicization of public health during the pandemic hasn't helped, but a panoply of other factors seems to be in play, too-including, in the case of polio, vaccines themselves. In recent years, commercial development has brought more people into contact with new diseases. Climate change has helped diseases spread to new animal and human populations. Airplane travel means an outbreak in one part of the world can quickly spread to another. And better testing is revealing outbreaks and new pathogens that might previously have gone unnoticed (the optimist's view).