The unnamed patient in Rockland County is said no longer to be contagious, but has developed paralysis from the virus, reports BBC.

Officials were quoted as saying by BBC that the person was unvaccinated, and was probably exposed to an individual who received a vaccine that contains the weakened live virus.

The US had last reported a polio infection case in 2013.

"Based on what we know about this case, and polio in general, the Department of Health strongly recommends that unvaccinated individuals get vaccinated or boosted with the FDA-approved IPV polio vaccine as soon as possible," State Health Commissioner Dr. Mary T. Bassett said."The polio vaccine is safe and effective, protecting against this potentially debilitating disease, and it has been part of the backbone of required, routine childhood immunizations recommended by health officials and public health agencies nationwide."

Polio is very contagious, and a person can spread the virus even if they aren't sick. Symptoms, which can be mild and flu-like (fatigue, fever, headache, stiffness, muscle pain, vomiting), can take up to 30 days to appear, during which time an infected individual can be shedding virus to others. Though rare, some polio cases can result in paralysis or death.

In this case, sequencing performed by the Wadsworth Center – NYSDOH's public health laboratory – and confirmed by CDC showed revertant polio Sabin type 2 virus.

This is indicative of a transmission chain from an individual who received the oral polio vaccine (OPV), which is no longer authorized or administered in the U.S., where only the inactivated polio vaccine (IPV) has been given since 2000.

This suggests that the virus may have originated in a location outside of the U.S. where OPV is administered, since revertant strains cannot emerge from inactivated vaccines.

"Many of you may be too young to remember polio, but when I was growing up, this disease struck fear in families, including my own," County Executive Ed Day said. "The fact that it is still around decades after the vaccine was created shows you just how relentless it is. Do the right thing for your child and the greater good of your community and have your child vaccinated now."

Due to the success of the vaccine, which was introduced in 1955, and a national vaccination program, polio cases were cut dramatically in the late 1950s and early 1960s, with the last naturally occurring cases of polio in the U.S. in 1979.

"Vaccines have protected our health against old and new viruses for decades," New York City Health Commissioner Dr. Ashwin Vasan said. "The fact is, the urgency of safe and effective vaccines has always been here, and we need New Yorkers to protect themselves against completely preventable viruses like Polio."