This photograph depicted a Centers for Disease Control and Prevention (CDC) scientist, concentrating poliovirus from sewage, so that the virus could be grown in cultured cells, and then tested using molecular methods. She was performing a polio environmental surveillance technique. There is no routine polio environmental surveillance in the U.S., but surveillance is done in many countries. A few other countries, like Haiti, send their sewage to CDC for analysis. This is a standard, World Health Organization (WHO) method, for processing and concentrating sewage, and environmental waters.