Deworming programme in India sparks controversy

India’s health ministry has launched the world’s largest mass deworming programme amid concerns that the government has disregarded multiple medical studies, including a Cochrane review that failed to find significant public health benefits for community deworming.

The programme, which began on 10 February, will provide albendazole twice a year to 140 million children aged 1-19 in 11 states with presumed high levels of soil transmitted helminths and once a year to 100 million children in other states.

The government said in a statement that the World Health Organization has estimated that about 241 million Indian children are at risk of infection with parasitic worms that have been associated with debilitating consequences on health and education. It said that the worms cause anaemia and undernutrition and that “rigorous research evidence shows that children when dewormed attend school more and have better cognitive development.”

But senior paediatricians and nutrition researchers have said that the government’s decision seems intended to launch something visible and convenient with little regard for evidence that raises questions about the effectiveness of mass deworming. “This decision does not appear to have been guided by evidence based medicine,” a senior community medicine and nutrition specialist in a government health institution told The BMJ, requesting not to be named.

A Cochrane review published three years ago found that community deworming had little or no effect on haemoglobin or cognition, and the evidence in relation to attendance and performance at school was “generally poor with no obvious or consistent effects.”1

A landmark study of one million children in northern India, published in 2013, found that taking albendazole twice a year had little impact on weight—after two years of treatment, the children who received albendazole weighed on average 0.04 kg more than those not given the drug.2

Paul Garner, professor at the Liverpool School of Tropical Medicine and coordinating editor of the Cochrane Infectious Diseases Group, told The BMJ, “This [plan] is misguided and potentially wastes public resources—while deworming obviously benefits individuals infected with worms, the population effects have been oversold.”

David Taylor-Robinson, clinical senior lecturer at the department of public health at the University of Liverpool and a coauthor of the Cochrane review, said, “Among over 40 randomised studies that we had included in the review, we found only three that showed some weight gain, and these were conducted over 20 years ago. Those who have taken the policy decision in India should justify on what evidence they have done this.”

However, Shally Awasthi, a paediatrician at the King George Medical University, Lucknow, who coauthored the 2013 albendazole study, told The BMJ, “I would not take up a sword against this programme. We have tens of millions of children living in conditions that put them at risk of worms and we know that the drug is safe and effective.”

Senior health officials have pointed out that the planned mass administration of albendazole through schools and government run childcare centres would require fewer resources than the mass screening of children to provide the drug only to those who have parasitic worms.

But doctors said that the epidemiology of soil transmitted helminths in India seemed to have changed over time. A study from the southern Indian town of Vellore published last year showed a prevalence of 7.9%, a sharp drop from 60% a decade ago.3

Harshpal Singh Sachdev, a paediatrician at the Sitaram Bhartia Institute of Science and Research, a private institution in New Delhi, told The BMJ, “One can’t be dogmatic about this programme—it is likely to have an impact in areas with a high burden of parasitic worms, but unlikely to benefit areas where worm loads have tapered down over the years. The problem is that we do not have reliable data of the worm loads in different parts of the country.”

Three years ago a government panel recommended that mass deworming should be conducted twice a year in areas where the worm prevalence is greater than 70% and once a year where the prevalence is between 50% and 70%.4 In areas with lower prevalence the drug should be given only to symptomatic children, it said.