Polio has been found in the sewer water of New York State, prompting health authorities to urge residents to get vaccinated to stop the spread of the easily preventable disease.
The New York State Department of Health (NYSDOH) launched a wastewater surveillance program to keep an eye out for polio after an unvaccinated adult contracted the disease in Rockland County in July 2022. This was the first confirmed case in the US since 2013.
Following probing from the US Centers for Disease Control and Prevention (CDC), the polio virus was then detected in wastewater samples from Rockland County that date back to June 2022.
Further analysis could even genetically link the wastewater polio virus to the human case identified in July, plus other environmental samples recently collected elsewhere in the world.
The person with polio in Rockland County was found to be infected with a virus strain called type 2 VDPV (vaccine-derived poliovirus). Genetic analysis found it to be related to the strain of the virus recently collected from environmental samples collected in the Israeli capital Jerusalem and the sewer water of London, UK.
These polioviruses are related to a weakened form of the virus used in some older forms of the oral polio vaccine. This weakened form of the virus can evolve over time and behave more like the naturally occurring virus, meaning it can potentially infect the unvaccinated. However, this oral polio vaccine has not been used in the UK or US for decades, suggesting the cases were likely imported from elsewhere in the world where this vaccine is still used.
Polio is a highly infectious viral disease that can affect the nervous system and cause muscle weakness, largely affecting children under 5 years of age. The polio virus typically enters the body through the mouth, usually from hands contaminated with the poop of an infected person, but transmission through saliva can also occur.
Although a huge threat to the population just decades ago, the disease is now preventable thanks to a safe and effective vaccination (which doesn’t include the weakened virus found in the oral polio vaccine).
Given the low vaccination rates in Rockland County though, it’s woefully unsurprising that polio has managed to experience a comeback. The polio vaccination rate here is 60.5 percent among two-year-olds, compared to the statewide average of 79.1 percent. Meanwhile, the US nationwide vaccination rate against polio is 92.6 percent.
Following the detection of the virus in Rockland County’s sewer water, public health experts are calling on all New Yorkers to make sure they and their families are up-to-date with their polio vaccinations.
"In the United States, we are so fortunate to have available the crucial protection offered through polio vaccination, which has safeguarded our country and New Yorkers for over 60 years. Given how quickly polio can spread, now is the time for every adult, parent, and guardian to get themselves and their children vaccinated as soon as possible," Dr Mary T. Bassett, State Health Commissioner, said in a statement.