Newborns and small children vaccinated against stomach flu are nearly 90 percent shielded against the bug that causes this potentially lethal disease, according to a study published.
More than half a million children under five die every year from gastroenteritis, mainly in low-income countries.
The rotavirus that causes the disease also accounts for more than 25 million outpatient visits and two million hospitalisations in the same age group every year.
The disease provokes severe diarrhoea and dehydration, which is especially dangerous in very young children.
In the study, led by Timo Vesikari of the University of Tampere in Finland, two-thirds of 3 994 infants between the age of six and 14 weeks were given two oral doses of Rotarix, a vaccine produced by GlaxoSmithKline.
The remaining newborns in the double-blind study were given a placebo, according to the study, published in the British journal The Lancet.
The vaccine offered 87 percent protection in the first flu season against rotavirus infection of any kind, and 96 percent protection against severe strains provoking serious diarrhoea.
Even a year later, the vaccine continued to work, providing 79 and 90 percent protection, respectively, against ordinary and severe forms of stomach flu.
Rotarix is one of two such vaccines on the market. The other, RotaTeq, produced by Merck and Co, has been shown to be similarly effective in preventing serious gastroenteritis infection.
In a commentary, also published in The Lancet, Kieth Grimwood of the Royal Children's Hospital in Brisbane, Australia and Julie Bines of the University of Melbourne say Rotarix "might do well in low-income countries in Africa and Asia, where rotaviruses circulate all year."
But they cautioned that due to the variety of strains present on these continents, further studies were needed before any recommendations could be made.
The peer-reviewed study, and the commentary, are authored by doctors who acknowledged having received payments in the past from GlaxoSmithKline for research, lectures or consulting.
The World Health Organisation (WHO) has said that rotavirus vaccines should be included in national immunisation schedules in regions with effective public health infrastructure.