Evidence provides an important catalyst for advocacy as well as for driving investments. One of the first tasks is to review the evidence base, determine where there is sufficient evidence to make further estimates, especially regarding burden of disease associated with WASH in health care facilities, and to identify the priority evidence gaps, and how they can be best addressed in tandem with health colleagues.
In addition, operational research on how to improve WASH services and practices in health care facilities most effectively is needed to inform effective implementation and further understand what drives and sustains change at the facility level and the other benefits of improving WASH such as increase uptake of services and greater patient satisfaction and confidence in care. Specific areas requiring further study include:
The interactions between WASH and IPC are many and includes issues such as personal washing, hand hygiene, cleaning of medical and surgical apparatus and equipment, general ward cleanliness, provision of sanitation, drinking water and washing water safety, health care waste and wastewater disposal. These distinct interactions may be classified into one of three broad areas:
 Nejad, S. B., Allegranzi, B., Syed, S. B., Ellis, B., & Pittet, D. (2011). Health-care-associated infection in Africa: a systematic review. Bulletin of the World Health Organization, 89 (10), 757-765.