While nutritional issues and diarrhoea have long been blamed for causing these, scientists are now looking at two new studies that found a large number of children with stunted growth did not suffer from diarrhoea.
According to them, infections due to the presence of four main pathogens -- Shigella bacteria, Campylobacter bacteria, enteroaggregative E. coli bacteria and the giardia parasite -- could be preventing them from reaching their full potential and perpetuate a vicious cycle of poverty.
In the studies, published in the journal The Lancet Global Health, the team found that more than 95 per cent of the children tested positive for at least one of these pathogens.
"It was surprising that these infections without diarrhoea were so common, and that they seemed to explain a large amount of the stunting," said Eric R. Houpt, from the University of Virginia.
"If we're just targeting diarrhoea, that may not be enough. We need to be addressing these asymptomatic exposures as well," added Liz Rogawski McQuade, from the varsity.
The studies examined more than 44,000 stool samples from children in eight countries: India, Pakistan, Nepal, Bangladesh, Tanzania, South Africa, Peru and Brazil.
Houpt noted that childhood infections have lasting effects.
"Stunting means children aren't growing and means that they get sick more easily," he said. "They don't do as well in school, and this can trap them in poverty."
Finding ways to address these infections among the world's children could have tremendous benefits. Vaccines, for example, are being developed for both Shigella and Campylobacter.
"If we could have interventions against just four pathogens, we would expect an improvement in growth that's similar to what has been seen for nutritional interventions in similar settings.
"This puts pathogen exposure, in terms of importance, on the same level as nutrition, which in the past has been considered the main reason for poor growth," McQuade said.
(With inputs from agencies.)