Polio virus detected in more upstate NY wastewater

State health officials in New York are warning of expanding "community spread" of the polio virus after it was found in wastewater samples from another upstate county.

The state Department of Health said Friday the polio virus was detected in four samples from Sullivan County, two each in July and August. Sullivan County is several dozen miles northwest of Rockland County, where officials on July 21 announced the first case of polio in the United States in nearly a decade. The unidentified young adult was unvaccinated.

The Sullivan County samples are genetically-linked to the case of paralytic polio in Rockland County.

State Health Commissioner Dr. Mary T. Bassett again urged residents to make sure they are immunized.

"One New Yorker paralyzed by polio is already too many, and I do not want to see another paralytic case," State Health Commissioner Dr. Mary T. Bassett said in a news release. "The polio in New York today is an imminent threat to all adults and children who are unvaccinated or not up to date with their polio immunizations. Every New Yorker, parent, guardian, and pediatrician must do everything possible to ensure they, their children, and their patients are protected against this dangerous, debilitating disease through safe and effective vaccination."

What to know about polio in NY

The virus has now been identified in wastewater samples in three contiguous counties north of New York City: Rockland, Orange and Sullivan. The polio virus also has been found in New York City sewage.

Officials have said that it is possible that hundreds of people in the state have gotten polio and don’t know it. Most people infected with polio have no symptoms but can still give the virus to others for days or weeks.

Polio was once one of the nation’s most feared diseases, with annual outbreaks causing thousands of cases of paralysis. The disease mostly affects children.

How Does Polio Spread?

Polio is considered very contagious and spreads mostly from person to person, through contaminated water and via fecal particles.

Health officials say the virus also can spread through droplets from an infected person's cough or sneeze, though that is less common.

What Are the Symptoms of Polio?

Most infected people have no visible symptoms. About a quarter will endure a few days of flu-like symptoms, such as fever, sore throat, headache and nausea.

A small fraction of people, however, can get more serious illness. The virus can infect a person's spinal cord, causing paralysis and possibly permanent disability and death.

The Associated Press contributed to this report.