By Ethan Covey
A case of paralytic poliovirus occurring in a previously healthy, yet unvaccinated, adult in New York with no history of international travel highlights the risks associated with polio, especially as vaccination rates wane.
Although only a single case has been identified, wastewater sampling has found vaccine-derived poliovirus type 2 (VDPV2) in two neighboring New York counties (MMWR Morb Mortal Wkly Rep 2022;71[33]:1065-1068).
“This is the first case of polio reported in the U.S. in nearly 10 years, and only the second instance of community transmission identified in the U.S. since 1979,” Ruth Link-Gelles, PhD, a doctoral epidemiologist with the CDC’s Division of Viral Diseases, told Infectious Disease Special Edition. “Thanks to widespread routine childhood polio vaccination in the U.S., the risk to the public is low and population immunity against paralytic polio is high.”
However, Dr. Link-Gelles noted that “even a single case of paralytic polio represents a public health emergency in the U.S.”
In June 2022, a young adult man arrived at an emergency department in Rockland County, New York, with a low-grade fever, neck stiffness, back and abdominal pain, constipation, and two days of bilateral lower extremity weakness. Stool specimens obtained on days 11 and 12 after initial symptom onset were positive for VDPV2.
Among 260 wastewater samples taken by Aug. 10 from treatment plants in Rockland and Orange counties, New York, 8% ¬yielded positive poliovirus test results (13 samples from Rockland County and eight from Orange County).
“Although no additional cases of polio have been reported at this time, these wastewater findings indicate that others in the community are likely shedding the virus in their stool,” Dr. Link-Gelles said.
Data from the New York State Immunization Information System show that polio vaccination levels in Rockland County are low, with just 67% of infants and children younger than 24 months of age having received three-dose polio vaccination coverage as of July 2020, and dropping to 60.3% by August 2022.
“This case and investigation provide an urgent reminder of the importance of vaccination,” Dr. Link-Gelles said. “Polio is a serious, life-threatening disease that has no cure, but it can be prevented through safe and effective vaccination.
“Anyone who is unvaccinated or incompletely vaccinated is at risk for developing paralysis if infected, and low vaccination coverage in the patient’s county of residence in New York indicates that the community is at risk for additional cases of paralytic polio,” she continued. “CDC urges all healthcare providers to ensure their patients are current on polio vaccine, especially those who may travel or be exposed to recent international travelers.”
Dr. Link-Gelles reported no relevant financial disclosures.