Less than a month after a polio case was diagnosed in New York for the first time in almost a decade, researchers in New York detected the presence of the poliovirus in wastewater samples.
Polio Case Identified in New York
On July 21, 2022, a resident of Rockland County, New York, tested positive for the poliovirus, which was the first time in almost ten years that the virus had been detected in the United States. Although public health officials are still not certain of where the individual had contracted the disease, they believe that the infected individual had previously interacted with someone who had received the oral polio vaccine. Importantly, this individual did not have any prior history of travel outside of the United States during the transmission window.
An unvaccinated person who is exposed to the poliovirus, even in a weakened form, can still become infected. Since up to 95% of individuals infected with poliovirus will remain asymptomatic, it has been challenging to identify potentially infected individuals.
Overview
Poliovirus is a nonenveloped, positive-sense, and single-stranded ribonucleic acid (RNA) virus that is a member of the Enterovirus genus within the Picornaviridae family. The most common route of exposure to the poliovirus is through the mouth, typically from hands that have been contaminated with the fecal matter of an infected person; however, respiratory and oral-to-oral transmission is also possible.
Following infection with the highly contagious poliovirus, the initial symptoms can resemble those commonly observed with the flu. These may include fatigue, fever, headache, congestion, muscle pain, and vomiting.
Although these symptoms will typically resolve within 30 days, rare severe forms of the disease can lead to paralysis and/or death. Importantly, an infected individual can continue to spread the virus to others during this symptomatic period.
Vaccination
The oral polio vaccine, which contains a weakened version of the live virus, has not been administered in the United States since 2000. Nevertheless, this version of the vaccine is safe and administered in many countries throughout the world.
In New York City, about 86% of individuals aged five and older are completely vaccinated against polio, with most adults having been immunized as children. The current polio vaccination schedule recommended by the United States Centers for Disease Control and Prevention (CDC) includes a total of four polio vaccine doses that are administered at two months old, four months old, between six and 18 months old, and between four and six years of age.
Notably, individuals who have received at least three doses of the current vaccine exhibit at least 99% protection against severe disease.
Conclusion
Despite the several decades of research supporting the safety and efficacy of current poliovirus vaccines, many vaccine-hesitant parents have declined to immunize their children or practice a “delayed vaccine schedule.” Thus, these children, as well as individuals who remain unvaccinated as adults, are at significant risk of infection, particularly if the virus remains in circulation.
The New York City Health Commissioner Dr. Ashwin Vasan emphasized the importance of vaccination, particularly in light of the probable local circulation of this virus.
Source:
https://www.news-medical.net/news/20220814/Poliovirus-detected-in-New-York-City-wastewater.aspx