Rotavirus is the leading cause of severe, acute gastroenteritis among infants and young children throughout the world and is responsible for an estimated 527,000 deaths among children under five each year. More than 90% of childhood deaths attributed to rotavirus infection occur in developing countries. Symptoms include severe diarrhoea and vomiting, leading to loss of fluid and electrolytes which can result in dehydration, shock, and death.
Safety and efficacy trials have already been conducted with two new rotavirus vaccines in Europe and the Americas which found they were more than 90% effective in preventing severe rotavirus gastroenteritis, but until now, no trials had been carried out in Africa or Asia, where the burden of disease is greatest.
One of the rotavirus vaccines – Rotarix, developed by GlaxoSmithKline Biologicals (GSK) – was tested in the Phase III clinical trial in Malawi and South Africa, which found that the vaccine reduced the overall incidence of severe rotavirus diarrhoea by 61.2%, although vaccine efficacy was lower in Malawi (49.4%) compared with South Africa (76.9%). The vaccine was able to prevent more rotavirus diarrhoea episodes in Malawi because of a higher rate of severe disease in the country. The new data informed a recent global recommendation of rotavirus vaccine by the World Health Organisation (WHO).
Dr Nigel Cunliffe, Reader in Medical Microbiology at the University of Liverpool, who led the study team in Malawi, said: "These data show for the first time that rotavirus vaccination can prevent severe diarrhoea in an African setting, where almost half of the total global burden of rotavirus deaths occurs.
"They demonstrate the large impact that rotavirus vaccines could have in countries with high diarrhoeal disease burden when introduced into their national childhood immunisation schedules."
The study in Malawi was conducted through a public-private partnership that included the University of Liverpool, University of Malawi College of Medicine, GAVI, PATH and GSK. Dr Cunliffe has investigated the disease burden and epidemiology of rotavirus infection in Malawi since 1997 in studies funded by The Wellcome Trust, the WHO and GSK.
The research is published in the New England Journal of Medicine.
Source: University of Liverpool