Indications of a “huge undiagnosed reservoir” of pediatric tuberculosis, with actual incidence much higher than the number of cases reported highlight the need for additional study of the disease in children, and an opportunity for improved prevention through household screening, a study released in The Lancet today says. Authors of the study, produced by researchers at University of Sheffield, Imperial College London and TB Alliance, estimate that in 22 high burden countries, which harbor 80 percent of the global TB burden, 650,000 children developed active tuberculosis in 2010, while 7.6 million became infected with the TB bacterium. 53 million children overall are estimated to have latent TB infection.
An estimated 15 million children live in the same household as an adult with tuberculosis, which also indicates a “failure to identify and treat adults with tuberculosis effectively.”
The study estimates that 5 percent of children living with HIV are co-infected with TB in the 22 high burden countries; however co-infection rates are much higher in certain countries, with South Africa and Zimbabwe seeing co-infection rates higher than 25 percent.
These numbers are higher than the World Health Organization’s estimate of 530,000 active TB cases among children last year. No estimate of pediatric tuberculosis incidence was published until 2012 when WHO produced the first numbers. Confirming diagnoses among children is challenged by lower bacteria levels, and children’s difficulties in producing sputum for samples. In addition, because children are perceived to pose less risk to others, even when diagnosed they are often not included in reported cases.
But, health economics researcher and lead author Peter Dodd, noted, “Quantifying the burden of TB in children is important because without good numbers, there can be no targets for improvement, no monitoring of trends and there is a lack of evidence to encourage industry to invest in developing medicines or diagnostics that are more appropriate for children than those available today.”
Click here to listen to a short podcast of study co-author James Seddon discussing pediatric TB.