Test water for bacterial indicators (such as E.coli, fecal coliforms or total coliforms). Frequency of water test varies depending on the water source, history of water quality, intended use of water and if water is in contact with fruits. When test results indicate fecal contamination, test the water for hepatitis A virus (HAV) and norovirus (NoV). If virus is detected, stop activities involving water (such as equipment sanitation and harvesting), repeat the water test to look for source of contamination and confirmed the presence of virus. Consider changing water source and notify local health authorities.