US doctor: “There could be hundreds or even thousands of undiagnosed polio cases”

A New York State health official told the BBC that in this area “there could be hundreds or even thousands of undiagnosed polio cases”.

The statement comes after it was announced last month that an unvaccinated man had been diagnosed with polio in Rockland, New York, the first case identified in the US in nearly a decade.

Dr. Patricia Schnabel Ruppert, Rockland’s health commissioner, said she is concerned because undetected polio is circulating in the state.

“Most cases are asymptomatic or mildly symptomatic, which are often missed.

“So there are hundreds, maybe even thousands of existing cases that we don’t see until we find a case with paralysis.”

The paralyzed US man has a form of polio derived from the vaccine containing an attenuated segment of the virus. Although weaker than the original or “wild” form of the disease, vaccine-derived polio can still cause serious illness. The virus can attack nerves in the spine and brain. This can cause paralysis, usually in the legs. If the respiratory muscles are affected, the patient’s life is endangered.

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