ALBANY, N.Y. (AP) — 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, saying “one New Yorker paralyzed by polio is already too many.”

“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,” Bassett said in a prepared release.

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.

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