The CDC has sent a team to New York to assist the state's health department with its investigation of a recent polio case in an unvaccinated man in Rockland County, ABC News reported Aug. 8.
The federal team is also helping with vaccination efforts.
"CDC continues to collaborate with the New York State Department of Health to investigate a recent case of paralytic polio in an unvaccinated individual from Rockland County," the CDC said in a statement to ABC News. "These efforts include ongoing testing of wastewater samples to monitor for poliovirus and deploying a small team to New York to assist on the ground with the investigation and vaccination efforts.
The health department on July 21 said an unvaccinated Rockland County resident contracted a case of vaccine-derived polio, meaning the person was likely infected by someone who received the oral polio vaccine, which uses active virus and is no longer used in the U.S. "This suggests the virus may have originated in a location outside of the U.S.," where the oral vaccine is still used, the health department said.
On Aug. 1, state health officials said polio virus had been detected in wastewater samples collected in June, suggesting it was present before the case was reported in July. Mary Bassett, MD, the state's health commissioner, on Aug. 4 said the case may be the "tip of the iceberg," with hundreds of other people potentially infected, based on additional wastewater samples genetically linked to the Rockland County patient.
"Although no additional cases have been identified at this time, these results indicate there is more than one person shedding the virus in their stool in these communities," the CDC said in its statement. "These individuals might have no symptoms or only mild symptoms, such as a sore throat and fever, but they can unknowingly still spread polio to those who are not protected by vaccination."