An unvaccinated young adult in New York recently contracted polio, the first case in the United States in nearly a decade, health officials said Thursday.
Officials said the patient, who lives in Rockland County, had developed paralysis. The person developed symptoms a month ago and had not recently traveled out of the country, county health officials said.
The patient appears to have had a vaccine-derived strain of the virus, perhaps from someone who received a live vaccine, available in other countries but not in the U.S., and spread it, officials said.
The person is no longer considered contagious, but investigators are trying to figure out how the infection occurred and whether other people were exposed to the virus. Most Americans are vaccinated against polio, but this should serve as a wake-up call to the unvaccinated, said Jennifer Nuzzo, a pandemic researcher at Brown University.
“This is not normal. We don’t want to see this,” Nuzzo said. “If you are vaccinated, you don’t have to worry. But if you haven’t had your kids vaccinated, it’s really important to make sure they’re up to date.”
Health officials scheduled vaccination clinics in New York for Friday and Monday and encouraged everyone who has not been vaccinated to get their shots.
“We want shots in the arms of those who need them,” Rockland County Health Commissioner Patricia Schnabel Ruppert said at a news conference Thursday.
Polio was once one of the most feared diseases in the country, with annual outbreaks resulting in thousands of cases of paralysis. The disease mainly affects children.
Vaccines became available starting in 1955, and a national vaccination campaign reduced the number of annual cases in the United States to less than 100 in the 1960s and to less than 10 in the 1970s, according to the Centers for Disease Control and Disease Prevention.
In 1979, polio was declared eliminated in the US, meaning it no longer routinely spread.
Rarely, travelers have brought polio infections to the US. The last such case was in 2013, when a seven-month-old boy who had recently moved to the United States from India was diagnosed in San Antonio, Texas, according to federal health officials. That child also had the type of polio found in the live vaccine used in other countries.
There are two types of polio vaccines. The US and many other countries use shots made from an inactivated version of the virus. But some countries where polio has been more of a threat recently use a live, weakened virus that is given to children as mouth drops. In rare cases, the weakened virus can mutate into a form capable of causing new outbreaks.
American children are still routinely vaccinated against polio with the inactivated vaccine. Federal officials recommend four doses: it should be given at two months of age; four months; six to 18 months; and from four to six years. Some states require only three doses.
According to the CDC’s most recent childhood vaccination data, about 93% of two-year-olds had received at least three doses of polio vaccine.
Polio is spread mainly from person to person or through contaminated water. It can infect a person’s spinal cord, causing paralysis and possibly permanent disability and death.
Rockland County, in the northern suburbs of New York City, has been a hotbed of vaccine resistance in recent years. A measles outbreak in 2018-2019 infected 312 people.
Last month, UK health officials warned parents to make sure children were vaccinated because the polio virus was found in sewage samples from London. No cases of paralysis were reported.