Researchers recently found that preventing the chain of cholera transmission within households in high-burden areas may significantly impact efforts to reduce the number of cases worldwide.
Work by Wellcome Sanger Institute and their collaborators published in Nature Genetics outlined nearly 80 percent of the cholera transmission in Dhaka, Bangladesh, a city with a hyper-endemic level of the disease, occurred between people who shared a household.
Authors said the work involved tracking cholera strains at a local level, from people within households, who shared a cooking pot and ate together.
Between 2002 and 2005, samples were taken from cholera patients admitted to the Dhaka Hospital of Bangladesh. Over a surveillance period of three weeks, follow-up samples were taken from other members in the same household of each cholera patient – as 303 Vibrio cholerae samples were collected from 224 individuals across 103 homes.
Investigators said they learned nearly 80 percent of the secondary infections were linked to the first case in that household, lending credence to the theory meant once cholera entered the household it was spreading between household members, rather than repeatedly coming in from outside, within the critical time period.
“Using genomics, we found that cholera is easily transmitted within the household,” Dr. Daryl Domman, the study’s first author from the Wellcome Sanger Institute, said. “Preventing this spread within the household could enormously reduce cholera outbreaks and highlights the need for prioritising local control strategies. This could have a huge impact, not only on the individual households but also on the entire region.”
According to figures released by UNICEF, cholera cases are on the rise, with 1.4 billion people at risk in endemic countries and an estimated 3 million to 5 million cases each year. It is estimated the disease causes up to 120,000 deaths per year globally.