Poliovirus was recently found in wastewater in three New York counties, including New York City. One case of paralytic polio was confirmed in an unvaccinated adult in Rockland County, which health officials say means the virus is likely circulating undetected.
“For every one case of paralytic polio identified, hundreds more may be undetected,” New York State Health Commissioner Dr. Mary Bassett said on Friday.
Polio vaccines are required for children entering kindergarten in all 50 states and the District of Columbia, though states allow medical exemptions and, in some cases, religious or philosophical exemptions as well.
The Centers for Disease Control and Prevention recommends four doses administered at specific intervals between the ages of 2 months and 6 years. The vaccine protects against severe disease in 99% of children who get the recommended doses, the CDC said.
CDC data shows that around 93% of U.S. kindergarteners had received four doses by the 2020-2021 school year. In Louisiana and Mississippi, vaccination rates were above 98%. But rates were far lower in other areas of the country: around 80% in the District of Columbia, 86% in Idaho and 87% in Wisconsin.
In Rockland County, where New York’s polio case was detected, only 60% of children have received three doses by the age of 2, according to the New York State Department of Health. The statewide average is nearly 79%.
National vaccination coverage dropped slightly among kindergarteners in 2020-2021 compared to previous school years.
In the 2019-2020 school year, 95% of kindergarteners were fully vaccinated for polio. Similarly, 95% had received the recommended vaccines for diseases like measles, whooping cough and chickenpox. Like the polio vaccination rate, that share fell slightly in the 2020-2021 school year, to 94%.