The Challenge

Globally, almost 1.9 million children die each year from diarrheal diseases caused by unsafe drinking water, inadequate sanitation facilities and poor hygiene each year.  It is the second largest cause of child mortality, after respiratory infections, accounting for 15 percent of child deaths globally, and 18 percent of child deaths in the poorest countries.  Chronic diarrhea in early childhood contributes to decreased food intake and nutrient absorption, malnutrition, reduced resistance to infection, and impaired physical growth and cognitive development, with long-term consequences for educational attainment and income.

The Global Health Response

The primary government and donor response to this disease burden has been to fund the construction of new water sources (e.g. wells), but recontamination during transport and storage remains a problem.

Treating water with chlorine has been a preferred solution as it both disinfects water and protects against recontamination.  Bottled chlorine sold in stores is widely available and well-known in the developing world, though it has been challenging to achieve high usage rates in rural households that are unable to afford commercial products.

The Challenge

Almost 5,000 children die each day from diarrheal diseases, a leading cause of which is unsafe drinking water. Chronic diarrhea in early childhood is believed to contribute to morbidity, malnutrition, stunting, and cognitive impairments, with lifelong consequences for educational attainment and income. Diarrhea’s serious impacts occur almost exclusively in the first 5 years of life, and it is recognized by the World Health Organization as a leading cause of child mortality as well as malnutrition.

Health interventions to reduce diarrheal disease in the development context fall into four general categories:  Improved water supply; household water treatment; the promotion of hand washing, and the provision of sanitation.

In poor rural areas where constructing piped water systems are prohibitively expensive, the government and donor response has generally been to fund new water sources such as wells or boreholes.  

However, this approach fails to ensure the safety of water after its transported home.  Because of unhygienic water collection behaviors and unsafe storage practices, re-contamination presents a major challenge in many settings. A study in Western Kenya showed that spring protection led to a 66% reduction in fecal contamination at the water source, but the reductions were only 24% in water stored in people’s homes. 

One inexpensive, safe, and effective option to improve water quality while protecting against re-contamination is to treat water with chlorine.  Chlorinated water provides ongoing protection from re-contamination typically lasting 24 hours. This method has been used for the last century to purify urban water supply in major cities in the developed world.  Chlorine can help at unimproved water sources and also help ensure that the benefits from source improvements, such as digging wells and protecting springs, are not lost due to re-contamination between collection and consumption

Chlorine is used to treat water in settings where piped systems are infeasible or prohibitively expensive. This water intervention comes in the form of household chlorination products which are promoted and sold at shops.  A common such product is a small bottle of chlorine solution with a special cap for adding a dose of chlorine to each container of water after it is collected. 

Extensive research has shown that treating household drinking water with dilute chlorine can reduce diarrhea in children by 40% for those who use chlorine regularly.  Unfortunately few households choose to regularly purchase and use such products.  Despite the relatively low price charged for point-of-use chlorine solution ($ 0.40 for a family of five for a month in Kenya) and years of extensive social marketing, well under ten percent of the population purchases chlorine each month.

Given the significant benefits of chlorination, finding ways to increase adoption by households can lead to significant progress on increased child survival as well as improved child health and development.