Following the discovery of a single confirmed case of polio, wastewater samples have suggested that the disease is spreading quietly across New York. Gov. Kathy Hochul declared a state disaster over polio on Sept. 9 in an effort to open up more vaccine resources. 

For every reported case of polio, hundreds more people may be infected, health officials said.

Nassau County is the newest county confirmed to have polio in its wastewater, according to a Sept. 9 announcement by New York's Department of Health. Polio has also been detected in samples from Rockland County, Orange County, Sullivan County and New York City. The findings in New York City's wastewater in August increased concern over polio because they suggest that the virus is circulating in the country's largest city. 

The first confirmed case of polio in the US in about a decade was reported in July in an unvaccinated person from Rockland County.

Hochul's declaration is meant to increase polio vaccination in New York by allowing additional people to administer polio vaccines, including midwives, pharmacists, emergency medical workers and other health care workers. The declaration will also require better information-sharing on polio immunization data among health officials, according to the news release.

"On polio, we simply cannot roll the dice," State Health Commissioner Dr. Mary T. Bassett said in the release. "If you or your child are unvaccinated or not up to date with vaccinations, the risk of paralytic disease is real." 

"I urge New Yorkers to not accept any risk at all," said Bassett.

Polio is a viral disease that disabled more than 35,000 people each year in the 1940s before there was a vaccine. It was declared eliminated from the US in 1979. 

Most people who contract polio have only mild or no symptoms, but others can become paralyzed or die. Between one in every 200 and one in every 2,000 people with polio will become paralyzed, according to the US Centers for Disease Control and Prevention, depending on the type of virus circulating.

But polio is a vaccine-preventable disease, and most adults today were vaccinated against polio as children. It's also a requirement for attending public schools in New York. The available vaccine for polio in the US -- which is recommended as a four-dose series typically given from the ages of 2 months through 6 years -- may be more than 99% effective at preventing paralysis and is credited with eliminating polio in the US. Though it isn't known how long the vaccine makes you immune, you're likely protected for many years after vaccination, per the CDC.

Some adults, including those traveling to certain countries and some health care or lab workers, may have had another vaccine dose after childhood. 

Rockland County and Orange County, where polio was previously detected, have vaccination rates of a little more than 60% and about 59%, respectively, compared with the statewide average of about 79%, health officials said. Vaccination rates against polio in New York City are a little over 86% in children up to 5 years old. 

"The risk to New Yorkers is real but the defense is so simple -- get vaccinated against polio," New York City Health Commissioner Dr. Ashwin Vasan said in August. "With polio circulating in our communities there is simply nothing more essential than vaccinating our children to protect them from this virus."

New York's health department recommends that all children and babies start the vaccination series for polio immediately if they haven't already. The health department also recommends that adults get three doses of the polio vaccine if they're unvaccinated, or are unsure whether they received the vaccine. Adults should also get the last one or two doses if they started the polio vaccine series but didn't finish, regardless of when they started it. 

Some people who have already been vaccinated against polio but are at increased risk of coming into contact with it may also get a booster, according to the latest announcement. This includes people who will have contact or might have had close contact with a person suspected to have polio (or that person's close contacts). It also includes health care providers in New York who might be in contact with the virus or handle samples, as well as people who are exposed to wastewater at their job.

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.