The CDC says the discovery of polio in New York City wastewater is the tip of the iceberg. That has many wondering if the contagious virus could also be in the Philadelphia region. Eyewitness News couldn’t find one location in the region that is testing wastewater for polio. Doctors say most people are vaccinated so the risk is considered low, but for those who aren’t protected, the CDC is worried about what it’s calling a silent spread. To read the full story.