The U.S. Centers for Disease Control and Prevention is expanding its wastewater testing for polio in parts of Michigan and Pennsylvania, officials announced Wednesday.
Polio outbreaks once caused panic in the United States but those concerns died once a vaccine was created and widely distributed in the 1950s and 1960s.
Concerns over the spread of polio have been renewed this year, however, after the first case of paralytic polio in nearly a decade was diagnosed in an unvaccinated man in Rockland County, N.Y., in July.
Since then, New York health officials have detected 89 “cases of interest,” 82 of which have been linked to the infected Rockland man. The virus has been found in sewage water in New York City, Orange County, Sullivan County, Queens County and Nassau County.
The CDC will begin wastewater testing in Michigan’s Oakland County and an unspecified area around Philadelphia.
“Wastewater testing can be an important tool to help us understand if poliovirus may be circulating in communities in certain circumstances,” said Dr. José R. Romero, director of the CDC’s national center for immunization and respiratory diseases. “Vaccination remains the best way to prevent another case of paralytic polio, and it is critically important that people get vaccinated to protect themselves, their families and their communities against this devastating disease.”
Polio can be found among communities with low vaccination rates and the virus can quickly spread. One out of every four people who contract the virus will eventually show flu-like symptoms such as a sore through, fever, nausea, headache and exhaustion.
But most people who contract the virus will show no symptoms, according to the CDC.
A smaller percentage of people will develop serious complications after contracting the virus.
There are two types of poliovirus vaccines. The first is a shot that can be administered in the leg or the arm that has an inactivated spread of the virus which has been in the United States since 2000.
The second in the oral vaccine which contains a weakened strain of the virus administered via a few small drops in the mouth. The oral vaccine is common outside of the U.S. but in communities with low vaccination rates, this method may allow the poliovirus to mutate leading to the spread of vaccine-derived poliovirus.