Aug. 12, 2022 -- Polio virus has been discovered in New York City’s sewers, suggesting the virus is circulating in the city, New York’s health authorities said today.

New York State Health Commissioner Mary Bassett, MD, MPH, called the detection of polio in NYC alarming.

Before this outbreak, the last case of polio in the United States was in 2013.

“For every one case of paralytic polio identified, hundreds more may be undetected,” Bassett said in a statement. “The best way to keep adults and children polio-free is through safe and effective immunization.”

Polio can cause permanent paralysis of limbs and even death in some cases.

Today’s announcement comes after a man in Rockland County, NY, north of the city, developed polio at the end of July and was paralyzed.

Now health officials fear the detection of polio in NYC wastewater could bring other cases of paralytic polio.

“It is not surprising since this is something already seen with Rockland County. This is solely the result of under-vaccination in the area. I think it’s likely that we will see a few paralytic cases but not a high number,” says  Amesh Adalja, MD, senior scholar at the Johns Hopkins Center for Health Security in Baltimore.
“It’s also critical to draw the distinction between circulating vaccine-derived polio [VDPV] and wild polio, which is only circulating in Afghanistan, Pakistan, and Mozambique,” Adalja says.  

Vaccine-derived polio “is a separate problem,” he says. It comes from the fact that much of world still uses the oral Polio vaccine – known as the Sabin vaccine --  which in rare circumstances can lead to polio disease in some unvaccinated people.

“Vaccine-derived polio will always be an issue so long as the Sabin vaccine is used — and it is used for good reasons since it is an oral vaccine and also induces shedding that can immunize others in close proximity.”

Vaccinations Declined in Pandemic

Among the worries is that vaccination rates across New York City dipped during the pandemic, as pediatrician visits were postponed.

In New York City, the overall rate of polio vaccination among children 5  and under is 86%. Still, in some city ZIP codes,  fewer than two-thirds of children in that age group have received the full dosage, which worries health officials. 

However, the Times notes, most adults were vaccinated against polio as children.

Across New York State, nearly 80% of people have been vaccinated. The unvaccinated are at risk but the polio vaccine is nearly 100% effective in people fully immunized.

New York health authorities are calling on the unvaccinated to get their shots immediately.

“The risk to New Yorkers is real but the defense is so simple – get vaccinated against polio,” New York City Health Commissioner Ashwin Vasan, MD, PhD,said in a statement. “Polio is entirely preventable and its reappearance should be a call to action for all of us.”

New York health authorities say that though many of the infected have no symptoms, about 4% will get viral meningitis “and about one in 200 will become paralyzed.”

Symptoms Can be Flu-Like

Symptoms can include those similar to the flu such as sore throat, fever, fatigue, nausea, and stomach ache. There is no cure for the disease. 

The city’s health department has given no details about where exactly polio had been found in NYC’s wastewater, nor did they give dates the virus was detected.

Health authorities urged parents of children who are not yet fully vaccinated to bring them to their pediatricians.

In 1916, polio killed 6,000 people in the US and left at least another 21,000 — most of them children — permanently disabled.

An outbreak in 1952 caused paralysis in more than 20,000 people and left many children on iron lungs. The first effective vaccine emerged just a few years later and the virus began to wane.