Tuberculosis Affects Children More Than Previously Thought; New Study Says About One Million Kids Under 15 Contract Disease Every Year

Tuberculosis Affects Children More Than Previously Thought

New Study Says About One Million Kids Under 15 Contract Disease Every Year

BETSY MCKAY

March 23, 2014 6:31 p.m. ET

About one million children world-wide under 15 years old contract tuberculosis every year, twice as many as previously thought, according to a new study from researchers from Brigham and Women’s Hospital and Harvard Medical School.

About 32,000 of those children have drug-resistant strains of the airborne disease, according to the study, published Sunday night in the Lancet journal.

TB experts have struggled to pinpoint the burden of the disease in children, because it is difficult to diagnose with standard methods used on adults. TB also affects children differently; as many as 30% who get it may develop the disease in parts of their body other than their lungs, doctors say.

The study is the first to estimate the burden of drug-resistant TB in children, a growing concern among pediatric TB specialists as difficult-to-treat strains spread around the world.

The authors used several sources of data to derive their estimates, basing them in part on the proportion of children whose TB is believed to be missed with a test using a patient’s sputum.

Using a different methodology, the World Health Organization estimates that about 530,000 children develop TB every year. But WHO and other public health officials say estimates and the methodology for producing them are still evolving. The first pediatric TB estimates were developed only about three years ago.

Public-health officials have traditionally focused their fight against TB on adults, because they are known to be infectious, while children were believed not to spread it. But the thinking has changed as drug-resistant TB has spread and as it has become clearer how sick children can get after contracting the disease.

Children become very ill quicker than adults once they are infected, and their TB is a sign of infection or disease in adult family members and others around them, said Mercedes Becerra, associate professor of global health and social medicine at Harvard Medical School and co-senior author of the study. “These one million children are missed opportunities for preventing TB every year,” she said.

Having accurate numbers for the pediatric TB epidemic is critical for funding purposes, said Jeffrey Starke, a pediatric TB expert at Texas Children’s Hospital in Houston who didn’t participate in this study. “People interested in child survival and the Millennium Development Goals are going to look for what diseases are causing most morbidity and mortality in the world,” he said.