UNB, Dhaka :
A double-dose, low-cost oral cholera vaccine administered through routine government health services can substantially reduce hospitalisation and deaths from cholera in densely-populated urban settings, finds a new study by icddr’b.
While oral cholera vaccines were previously shown to be effective in trial settings, this is the first study to prove their effectiveness and feasibility in a real-life situation.
The findings of the study, published in The Lancet, lend support to the use of vaccines in routine mass vaccination programmes to help control cholera in endemic countries.
The cholera burden is greatest in the developing countries where a large number of people live in unsanitary conditions without access to clean water, factors which are critical to the spread of cholera.
Bangladesh alone has an estimated 300,000 cases and 4,500 deaths each year due to cholera
(WHO 2012).
Dr Firdausi Qadri, Director for Centre for Vaccine Sciences at icddr’b and the principal researcher, said their findings show that a routine oral cholera vaccination programme in cholera-endemic countries could substantially reduce the burden of disease and greatly contribute to cholera control efforts.
The study took a cluster-randomised trial approach where the participants were randomly assigned to one of three groups: those who received Shanchol vaccine, those who received Shanchol and an intervention that encouraged hand washing and drinking water treatment with chlorine, and those who received no intervention at all, the control group.
The results show that at 65 percent vaccination coverage level the incidence of severely dehydrating cholera was reduced by 37 percent in the overall study population, irrespective of their vaccination status.
The incidence of cholera decreased by 45 percent in the group that received both vaccination and hand washing-water treatment intervention.
For participants that received the full two doses of the vaccine, the rate of hospitalisation decreased by more than 50 percent.
For individuals who were vaccinated, it was shown to confer 53 percent protection two years after the vaccine was administered, a finding consistent with previous field trials.
Dr Qadri said, ultimately the key to controlling cholera is clean water, improved hygiene practices and adequate sanitation facilities, which half the developing world – around 2.5 billion people – lack.
These improvements require large investments for major infrastructural changes which remain a rather difficult reality for the world’s poorest nations as well as those affected by climate change, war and natural disasters.
A double-dose, low-cost oral cholera vaccine administered through routine government health services can substantially reduce hospitalisation and deaths from cholera in densely-populated urban settings, finds a new study by icddr’b.
While oral cholera vaccines were previously shown to be effective in trial settings, this is the first study to prove their effectiveness and feasibility in a real-life situation.
The findings of the study, published in The Lancet, lend support to the use of vaccines in routine mass vaccination programmes to help control cholera in endemic countries.
The cholera burden is greatest in the developing countries where a large number of people live in unsanitary conditions without access to clean water, factors which are critical to the spread of cholera.
Bangladesh alone has an estimated 300,000 cases and 4,500 deaths each year due to cholera
(WHO 2012).
Dr Firdausi Qadri, Director for Centre for Vaccine Sciences at icddr’b and the principal researcher, said their findings show that a routine oral cholera vaccination programme in cholera-endemic countries could substantially reduce the burden of disease and greatly contribute to cholera control efforts.
The study took a cluster-randomised trial approach where the participants were randomly assigned to one of three groups: those who received Shanchol vaccine, those who received Shanchol and an intervention that encouraged hand washing and drinking water treatment with chlorine, and those who received no intervention at all, the control group.
The results show that at 65 percent vaccination coverage level the incidence of severely dehydrating cholera was reduced by 37 percent in the overall study population, irrespective of their vaccination status.
The incidence of cholera decreased by 45 percent in the group that received both vaccination and hand washing-water treatment intervention.
For participants that received the full two doses of the vaccine, the rate of hospitalisation decreased by more than 50 percent.
For individuals who were vaccinated, it was shown to confer 53 percent protection two years after the vaccine was administered, a finding consistent with previous field trials.
Dr Qadri said, ultimately the key to controlling cholera is clean water, improved hygiene practices and adequate sanitation facilities, which half the developing world – around 2.5 billion people – lack.
These improvements require large investments for major infrastructural changes which remain a rather difficult reality for the world’s poorest nations as well as those affected by climate change, war and natural disasters.
