How are dormant diseases making a comeback?

Two diseases that are usually dormant in the United States – monkeypox and polio – have been found in the country.

Monkeypox is an outbreak for the first time since 2003. It is most prevalent among gay men. 

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Also, the first case of polio in the country since 2013 was found in a New York resident who was unvaccinated, but may have had contact with someone who received an oral polio vaccine. The U.S. no longer uses these vaccines.

But how are these usually dormant diseases infecting people?

"Any infectious disease can get into the population if it infects the wrong person at the wrong time, who can then spread it," said Dr. Matthew Sims, the director of infectious disease at Beaumont. 

Sims says outbreaks happen when there’s a significant number of unvaccinated people. 

While most cases of monkeypox and the case of polio happened to adults, the World Health Organization says globally 23 million children did not receive their routine vaccines during the height of the COVID-19 pandemic. 

Several studies show children vaccination rates dropped 80% during the pandemic, making diseases like chickenpox, measles, and mumps prime for a potential outbreak. 

"There is definitely a concern about kids who missed vaccines during the pandemic when we were in lockdown and have not caught up, some of which the parents aren’t intending to catch up," Sims said.