Acanthamoeba cysts are known to be resistant to chlorine used for disinfecting water and therefore may survive in water.[1] This may lead to widespread dispersal of cysts. Many hospitals have water storage tanks for emergency water supply. They may also act as source of contamination by FLA.[12] One sample in our study was collected from such storage tank but it turned out to be negative in culture thereby demonstrating that contamination was taking place in pipes which may be due to the persistence of these FLA in the biofilms. Taking into account, the increase in the immunosuppressed population, it is very important to take urgent steps to prevent nosocomial infections by these agents or by the drug resistant bacteria they harbour. There are no guidelines for the prevention of colonisation by amoeba in health care settings. However, going by the results of our study and others, there is an urgent need to focus on methods of prevention/removal of biofilms caused by FLA in hospital water especially those housing high risk patients. Servicing/ replacement of the RO filter seemed to eradicate the focus. However the frequency of sampling and/or servicing needs to be explored in future studies.