London: Almost 25 per cent more children are developing tuberculosis (TB) than the WHO had estimated, with India having by far the highest burden of childhood TB among the 22 worst affected countries, according to a new study.
The study, published in The Lancet Global Health, found that over 650,000 children develop tuberculosis (TB) every year in the 22 countries with a high burden of the disease (HBCs).
The number was estimated at 530,000 by the World Health Organization (WHO) in 2012.
The new research which used mathematical modelling found that about 7.6 million children younger than 15 years in the 22 HBCs became infected with Mycobacterium tuberculosis in 2010 and of those, roughly 650,000 developed TB.
India had the highest burden of childhood TB, accounting for 27 per cent of the total burden in these countries.
“In our model India had by far the highest burden of paediatric tuberculosis, which is probably a result of its large size, demographic composition, and moderate tuberculosis prevalence,” researchers said.
The study also suggests that about 15 million children are exposed to TB every year, and roughly 53 million are living with latent TB infection, which can progress to infectious active TB at any time.
“Our findings highlight an enormous opportunity for preventive antibiotic treatment among the 15 million children younger than 15 years of age who are living in the same household as an adult with infectious TB,” said lead author Dr Peter Dodd from the University of Sheffield in the UK.
“Wider use of isoniasid therapy for these children as a preventative measure would probably substantially reduce the numbers of children who go on to develop the disease,” Dodd said.
In contrast with standard estimates that are reliant on paediatric case reporting, which varies widely between countries, the researchers used mathematical modelling to estimate rates of infection and disease in children based on country-specific data on household and population structure, and the prevalence of TB in adults.
The overall estimated case detection rate was 35 per cent – meaning that 65 per cent of active TB cases in children are missed every year by national TB programmes.
This case detection rate is substantially lower than the WHO estimate of 66 per cent in adults.
The 22 countries with high burden of tuberculosis are Afghanistan, Bangladesh, Brazil, Cambodia, China, DR Congo, Ethiopia, India, Indonesia, Kenya, Mozambique, Myanmar, Nigeria, Pakistan, Philippines, Russia, South Africa, Thailand, Uganda, Tanzania, Vietnam, and Zimbabwe.