GlaxoSmithKline's vaccine against rotavirus, a disease which kills one child a minute in the developing world, has been endorsed by the World Health Organisation.
This is the first such vaccine to win "pre-qualification status", which certifies its quality, safety and efficacy and allows agencies such as Unicef to use it for mass vaccination programmes.
Glaxo's vaccines head, Jean Stephenne, said the vaccine Rotarix would be offered at tiered prices, with the lowest prices reserved for the public sector in the world's poorest countries.
Rotavirus infects virtually every child in the world within the first five years of its life and is the most common cause of severe diarrhoea in children. Europe accounts for 20 per cent of the total market for the vaccine. But poor provision of healthcare in developing countries makes the disease a killer as children suffering from diarrhoea-related diseases do not get effective treatment. Globally, rotavirus infections are responsible for more than 600,000 deaths per year.
Glaxo said it first registered Rotarix in Latin America and Africa due to the "dire healthcare provision" in countries there.
In Latin America and the Caribbean, rotavirus is responsible for 13,100 deaths each year. Around 170,000 children have to go to hospital with rotavirus gastroenteritis every year in Latin America, creating a massive economic, social and emotional burden.
The rotavirus market is estimated to be worth a potential £1bn to £1.3bn by 2010. Although children in about 50 countries are already being vaccinated, after yesterday's ruling this will increase to 90 countries.
WHO pre-qualification status facilitates the supply of vaccines to countries where they are most urgently needed.
Dr Jon Andrus, from the Pan-American Health Organisation (PAHO), said the decision will allow PAHO and other groups to buy vaccines on behalf of "resource-poor and middle-income countries".
Along with sales of its vaccines, Glaxo also runs a global education programme across 10 countries.Reuse content