Given the impact of handwashing on health, nutrition, education, and equity, lack of investment in handwashing has important economic implications at the population level. Investigations are currently underway to quantify the costs of not investing in handwashing, contrasted with the benefits of making these investments.
Focusing just on the health returns, handwashing is one of the most cost-effective investments in public health. Disability-adjusted life years (DALYs) are a unit of measurement that help define the burden of any particular disease by combining information about years of life lost and years lived with a disability. DALYs help us measure the effectiveness of health interventions. So, when we compare interventions that have health benefits, like handwashing to prevent diarrheal diseases, we are comparing the cost per one DALY averted. Handwashing with soap has been shown to be the most effective way to avert DALYs associated with diarrheal diseases.
The World Health Organization’s Commission on Macroeconomics and Health outlines the cost effectiveness of health interventions based on the cost per DALY averted. For example, interventions that avert one DALY at less than the cost of the per capita Gross Domestic Product (GDP) are classified as “very cost effective”. Interventions that avert one DALY at 1-3 times the cost of GDP are designated “effective”. The cost of averting one DALY through hygiene promotion including handwashing is US$3.35. The country with the lowest per capita GDP is currently Congo, where the per capita GDP is US$394.25. Thus, even in the world’s lowest income countries, handwashing is expected to be highly cost effective.[i]
Handwashing is particularly cost effective when compared to other interventions. For example, a US$3.35 investment in handwashing promotion is estimated to deliver the same amount of health benefits as a US$11 investment in latrine construction, a US$200 investment in household water supply, or an investment of many thousands of US dollars in immunizations.
Handwashing is also orders of magnitude less expensive than other public health interventions. For instance, one DALY requires investment in measles immunization anywhere from US$250 to US$4,500. This is not to say that immunization is not essential; it is simply to point out the tremendously inexpensive life-saving opportunities being missed by the widespread failure to invest in handwashing promotion.
Economic analyses conducted for Bangladesh, Kenya, Malawi, and Zambia suggest that in these countries combined over half a billion US dollars a year could be saved by investing in handwashing programs to prevent diarrhea and pneumonia in children under the age of 5.
A 2017 study estimated that a national handwashing programme in India could yield returns of net US$ 5.64 billion. This amounts to a 92-fold return on investment. In China, a similar program for China could yield a net annual return of US$ 2.64 billion, which amounts to a 35-fold return on investment. According the the authors of this study, “With these very high estimates of benefits to costs, well-designed national handwashing behaviour change programmes in India and China should substantially reduce the heavy burden of disease and offer excellent value for money.”
The economic benefit from handwashing is not isolated to the prevention of diarrhea and pneumonia, as infections from other sources also pose an economic cost to countries. Healthcare-associated infections (HAIs), the majority of which can be prevented by good hand hygiene, are extremely costly to individuals, healthcare systems, and countries. The economic loss attributed to the direct costs associated with HAIs in Europe is €7 billion per year. In the United States, the annual cost was estimated in 2004 to be US$6.5 billion.
[i] Walker DG, Hutubessy R, Beutels P. WHO guide for standardisation of economic evaluations of immunizations programmes. Vaccine. 2010 Mar 8; 28(11):2356-9.
[ii] Jamison DT. Disease Control Priorities in Developing Countries. World Bank; 2006.
[iii] Townsend J, Greenland K, Curtis V. Costs of diarrhoea and acute respiratory infection attributable to not handwashing: the cases of India and China. Tropical Medicine & International Health. 2017