SODIS, short for solar disinfection, is one of the verified ways to sanitize water (1). SODIS utilizes the natural heat and UV-A rays directly from sunlight to kill viruses, parasites, and bacteria, making unclean water safe to drink (1).
The ability to disinfect water with solar radiation was first discovered by a Lebanese scientists in 1984. However, the method was not heavily investigated until the 1990s, when it was verified by the Swiss Federal Institute of Aquatic Sciences and Technology (2). The main criteria of interest were the efficacy and global applicability of solar disinfection. The end result was that it was determined that solar disinfection was effective at killing pathogens, affordable, and easy to use (3). These investigations led to the development of a standard procedure, known as the SODIS method (3).
The Swiss Federal Institute began implementing several SODIS projects in developing countries in 2001 (2). Additionally, several multi-institutional efforts continued to verify the efficacy and health benefits of SODIS, as well as explore innovations in SODIS procedure that can improve its use globally, particularly in developing countries that suffer the most from unclean water (4).
Today, SODIS is recognized by the World Health Organization, the CDC, UNICEF, and the Red Cross as a way to sanitize water in developing countries (3). The CDC estimates that over 5 million people in nearly 30 developing countries use SODIS for daily drinking water (5). However, it remains that SODIS is not consistently promoted or adopted around the world for a myriad of reasons, such as cultural or lifestyle differences, understanding of the procedure, and efficacy of SODIS teaching (2). Thus, while SODIS may be verified as an effective sanitation method, the challenge to implement it still remains.