A study published in The Lancet is the first clinical trial to show that immunisation with a new vaccine called Vi-TT is safe, well tolerated and will have significant impact on disease incidence in typhoidendemic areas that introduce the vaccine.
The vaccine has been submitted by Bharat Biotech of India Ltd. to the World Health Organisation (WHO) for prequalification. This determines that the vaccine is safe and effective and can be procured by UNICEF for use in low-resource settings.
Typhoid is caused by the bacterium Salmonella Typhi, and is responsible for around 20 million new infections and 200,000 deaths each year, mainly in South and South East Asia and Africa.
The disease is associated with inadequate sanitation and contaminated drinking water, and common symptoms include fever, stomach pain, headache and constipation or diarrhea.
Children are especially susceptible, but the currently licensed vaccines do not confer lasting immunity in children, and/or come in inappropriate formats.
The trial was led by Professor of Paediatric Infection and Immunity at the University of Oxford, and Director of the Oxford Vaccine Group, Professor Andrew Pollard and funded by a grant from the Bill & Melinda Gates Foundation.