The polio virus was present in sewage in a New York City suburb a month before health authorities announced a confirmed case of the disease last month, the state health officials Monday and urged residents to make sure they’ve been vaccinated.

The discovery of the illness from sewage samples collected in June means the virus was present in the community before the Rockland County adult’s diagnosis was made public on July 21.

Laboratory tests also confirmed that the strain in the case is genetically linked to one found in Israel, though that doesn’t mean the patient traveled there, authorities added.

The Global Polio Eradication Initiative, a nonprofit organization, said last week that initial genetic sequencing also linked him to samples of the highly contagious and life-threatening virus in the UK.

The patient had started showing symptoms in June, when local officials asked doctors to be on the lookout for possible cases, according to the New York Times.

“Given how quickly polio can spread, now is the time for all adults, parents and guardians to vaccinate themselves and their children as soon as possible,” said State Health Commissioner Dr. Mary Bassett. .

There is no cure for polio, once one of the most feared diseases given its ability to cause irreversible paralysis in some cases, but it can be prevented with a vaccine available since 1955.

New York officials have said they are opening vaccine clinics to help unvaccinated residents get their dose. Polio is often asymptomatic, and people can spread the virus even when they don’t appear to be sick. However, it can produce mild flu-like symptoms that can take up to 30 days to appear, officials said.

It can appear at any age, but most of those affected are children three years old or younger.

Representatives from the New York health department could not immediately be reached for more details about the findings in sewage. The US Centers for Disease Control and Prevention also did not immediately return a request for comment.

The polio vaccine developed by Dr. Jonas Salk in the 1950s was heralded as a scientific breakthrough in tackling the global scourge. The United States has not seen a domestically generated case of polio since 1979, although cases were found from a traveler and an oral vaccine was discovered in 1993 and 2013.