Purpose: The objective of this study was to evaluate the effectiveness of typical hand-washing techniques in villages in Malawi.
Methods: Children and adults (n = 113) from of Malawi were assigned one of four treatment groups (water only, and water with red bar soap (RS), green bar soap (GS), or liquid soap (LS)). Objective cleanliness scores were recorded for each set of hands. A sterile swab was used to sample one hand, assigned washing treatment performed, and another swab was used on the other hand of the same individual. Water samples were collected using sterile plastic tubes (n = 3) and utensils used to transport water were swabbed prior to filling with water (n =2). All samples were analyzed for aerobic plate count (APC), coliform and generic Escherichia coli in duplicate. Samples were quantified at two university laboratories in Malawi.
Results: Before washing, hands averaged 5.24 log CFU/hand, with no reduction of APC from any treatment. Liquid soap was most effective at reducing coliforms from 5.29 to 4.27 CFU/hand, and generic E. coli from 5.42 to 2.87 CFU/hand after washing. Water samples tested averaged an APC total of 3.09 log CFU/ml and 36.33 CFU/ml of coliforms, while utensils used to transport water had an average of 7.48 CFU/swab APC indicating that they could be a source of hand contamination.
Significance: The importance of hygiene beyond a request to utilize hand-washing was made evident in this study. Further investigation and outreach is needed to educate these communities on the importance of cleaning available water and washing utensils for hand-washing to be an effective hygiene improvement.