‘Cholera hospital-based intervention for 7 days’ (CHoBI7) promotes handwashing with soap and treatment of water with chlorine tablets to protect people at risk of contracting cholera during the one week-period that a cholera case is admitted to hospital.
The scientists who developed CHoBI7 observed high rates of infection within households of cholera patients because of shared environments and poor hygiene practices. Their findings from a study on CHoBI7, conducted in 2013—2014 and due to be published in Emerging Infectious Diseases this month (February), show that household members had a 100 times higher risk of contracting cholera than the general population.
The study involved randomised trials among 219 intervention household contacts of 82 cholera patients and 220 control contacts of 83 cholera patients at the international centre for diarrhoeal disease research (icddr,b), Dhaka. Intervention contacts had significantly fewer symptoms of cholera infections than control contacts and 47 per cent fewer infections.
Munirul Alam, an author of the study, tells SciDev.Net that “no standard of care exists for household contacts of these patients despite their very high risk for cholera contamination. We communicated information about water sanitation and hygiene when patients and their accompanying family members spend time at our hospital facility and also provided them with a kit.” The CHoBI7 kit includes a pictorial on how cholera can spread through contaminated food and water in the home and instructions on proper handwashing with soap and treatment of water and a package containing supplies of chlorine tablets for water treatment, bottles of soapy water and a covered vessel for safe water storage.
Alam says that CHoBI7 was developed as a low-cost standard of care for members of the households of cholera patients. “The bigger story of this study’s outcome is that CHoBI7 could prevent a cholera epidemic and stunting, because multiple episodes of diarrhoea can lead to loss of nutrition which is a major factor in child growth.”
Christine Marie George, lead author of the study and assistant professor at the Johns Hopkins Bloomberg School of Public Health, tells SciDev.Net that the findings suggest that hospital-based intervention is a cost-effective approach that could be initiated as standard of care for household members of cholera patients. “Future studies should investigate the efficacy of CHoBI7 in other settings affected by cholera globally, evaluate the effects of CHoBI7 on other enteric pathogens, and identify effective low-cost approaches to take CHoBI7 to a larger scale,” she says.
Christine Marie George acknowledges limitations in the study such as the inability to establish the effect of handwashing with soap and treating water, the small sample size and the inability to obtain culture results from as many household contacts as anticipated.
Mohammad Yunus, a world expert on diarrhoea and formerly attached to the icddr,b, says that the findings of the study are “crucial as it can benefit global communities burdened with such deadly waterborne diseases.”
Christine Marie George — who was awarded US$ 1.5 million from the US Agency for International Development to partner with Alam and his team to develop the intervention — says that severe cholera without adequate treatment turns fatal in 50 per cent of cases.
According to WHO estimates 3–5 million cholera cases occur worldwide annually.
This piece was produced by SciDev.Net’s South Asia desk.