PHILADELPHIA (WPVI) -- The CDC is including Philadelphia in its expanded wastewater testing to detect polio.
Specific communities will be targeted for analysis based on low polio vaccination rates.
"Wastewater testing can be an important tool to help us understand if poliovirus may be circulating in communities in certain circumstances," Dr. José R. Romero, Director of CDC's National Center for Immunization and Respiratory Diseases, said in a news release Wednesday.
The goal is to help prioritize vaccination efforts in communities of concern.
When poliovirus is found in communities that have low vaccination rates, the CDC says it can spread among unvaccinated individuals, putting them at risk for becoming infected and developing polio.
"Vaccination remains the best way to prevent another case of paralytic polio, and it is critically important that people get vaccinated to protect themselves, their families and their communities against this devastating disease," Romero said.
The testing program will last at least four months.
The CDC says finding poliovirus in sewage or wastewater indicates that someone in the community is shedding poliovirus.
"Wastewater data cannot be used to determine or identify who is infected or how many people or households are affected, but it can enhance other data that are used as part of polio prevention programs, including rapid investigation of suspected polio cases," the CDC said.
The CDC says in the United States, the risk of polio to the public is low because most people - greater than 92% of Americans - were vaccinated during childhood.