Fortified salt delivered through a social enterprise proves cost effective for warding off tropical disease, study finds
A University of Notre Dame study has shown that a novel social enterprise program to fortify and deliver salt via the marketplace in Haiti has not only been effective at combatting a tropical disease, but is also more cost-effective and financially sustainable than annual mass drug distribution efforts.
Salt fortified with the drug diethylcarbamazine (DEC) was found to be effective at killing the parasitic worms, spread by mosquitos, which cause Lymphatic Filariasis (LF), according to the study by Edwin Michael, professor in the Department of Biological Sciences. Published in PLOS Neglected Tropical Diseases, the study also showed that Bon Sel+ Dayiti, a fortified salt social enterprise, became profitable over time. This indicates that introducing DEC through edible salt sold in the market can offer a sustainable option for eliminating LF in difficult to control settings.
LF is caused by parasitic worms that attack the lymphatic system. It is often contracted during childhood, but the symptoms — including severe swelling, embarrassing disfigurement, and pain — usually don’t manifest themselves until adulthood. The World Health Organization (WHO) originally set 2020 as the year for worldwide eradication.
Fortified salt had already proven to be effective in other parts of the world. In China, for example, the government mandated its use, and LF has been eradicated there. The method was more difficult in Haiti because of government unrest, natural disasters, and distribution issues because of a transient population. Mass drug administration (MDA) was the primary way to fight against the disease.
“But it is very difficult to get high coverage,” Michael said. “And because it is given only annually, patients are getting the DEC intermittently rather than continuously over time.” Such applications only kill 40 to 50 percent of the worms each time, and it takes six to 10 years of MDA to control the disease.
The large dose also had more side effects. But when small amounts are mixed in salt, along with iodine — which combats iodine deficiency, the leading cause of mental retardation worldwide — people are receiving a more frequent, sustained, and controlled dose. Since 2006, the Notre Dame Haiti Program supported production of salt, with technical assistance provided by Cargill Salt. Distribution has been done through a direct sales force in Leogane, Haiti, as well as a top food company in the country.
Michael’s study used a cost-revenue analysis and financial forecasting to compare the cost of the salt social-enterprise program with the MDA program. Results showed the salt program costs about 30 percent of the cost of the traditional MDA program, which is still being done in tandem.
“This year or next year, the salt enterprise is predicted to break even, and everything after that is profit,” Michael said. “And now that our paper has modeled the impact of the program, we would like to look at empirically measuring the impact on infection in the field, as well as investigate the impact that iodine has on health in the country.”
Michael, who is affiliated with the Kellogg Institute for International Studies, sits on the WHO/Gates Foundation panel for modeling neglected tropical diseases and has suggested the approach be tried in Africa. “For me this is the most exciting thing, that the Notre Dame Haiti Program has helped build an innovative social enterprise approach that is helping eradicate a neglected tropical disease. This will add to the mix of approaches we currently have for combating diseases that continue to afflict the poorest populations of the world. It will also foster a ‘rethink’ of the ways by which these diseases can be cost-effectively eliminated ”
In addition to Michael, collaborators include Swarnarli Sharma, Morgan E. Smith, Jean M. Brissau, Marie C. Donahue, and Clarence E. Carter, all of the University of Notre Dame, as well as James Reimer, salt program director, and David B. O’Brien, retired international tax planner at Deloitte. The study was funded through the Notre Dame Haiti Program.