Over 50 million children infected with tuberculosis

A new study quantifying the global TB burden among children points to a huge undiagnosed reservoir of TB.

Researchers at the University of Sheffield, Imperial College London, and TB Alliance have found evidence that a large gap exists between the number of TB cases in children that get notified to authorities and the true underlying incidence.

The gap, detailed in a study published today in the journal Lancet Global Health, shows that TB in children is a major public health problem worldwide.

The investigators estimated the number of children with TB in the 22 countries with the highest burden of TB in the world. The study suggests that in these countries more than 650,000 children developed the disease in 2010, while 7.6 million became infected with the TB bacterium. Overall more than 53 million children were estimated to latently harbour the infection.

Diagnosing TB in children can be challenging and the disease can often be overlooked or mistaken for something else. This can lead to under-reporting, distorting the true scope of the problem and the real demand for paediatric TB treatment.

The first estimates of paediatric TB by the World Health Organization (WHO) were published in 2012, and last year the WHO estimated 530,000 paediatric cases worldwide. However, given the acknowledged difficulties in detecting TB in children, there is need for additional study and focus on the burden of disease in children.

Health economics researcher Peter Dodd, from the University of Sheffield’s School of Health and Related Research (ScHARR), said: “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.”

He added: “Historically, TB in children has not received the attention that it might have done. The WHO is now encouraging countries to report the number of TB cases they find in children, but we still have only a poor idea what proportion of cases are recorded in youngsters.”

For the first time, researchers used a mechanistic mathematical model to estimate the number of cases of paediatric TB in the 22 high TB burden countries, which are reported to harbour 80 per cent of the global burden. In addition to providing global estimates, the study also revealed additional findings.

Over a quarter of all paediatric TB cases were found in India and 15 million children under the age of 15 were found to be living with somebody with TB. The 53 million children with latent TB represent a huge reservoir for future disease.

Co-author on the study, Dr James Seddon from the Department of Medicine, Imperial College London, said: “Although these 53 million infected children may not be currently experiencing any problems they are at a very high risk for developing the disease in the future.

It is also interesting to note that only a third of children with TB disease are currently identified, treated and reported. This compares to two thirds in adults.”

The study is part of a larger effort, led by TB Alliance and supported by UNITAID and USAID, to improve TB treatment for children and deliver optimised child-friendly first-line TB drugs. This study adds to the growing body of research examining the true burden of paediatric TB.

Additional information To read the full paper please visit http://www.thelancet.com/journals/langlo/article/PIIS2214-109X(14)70245-1/abstract The University of Sheffield

With almost 25,000 of the brightest students from around 120 countries, learning alongside over 1,200 of the best academics from across the globe, the University of Sheffield is one of the world’s leading universities.

A member of the UK’s prestigious Russell Group of leading research-led institutions, Sheffield offers world-class teaching and research excellence across a wide range of disciplines.

Unified by the power of discovery and understanding, staff and students at the university are committed to finding new ways to transform the world we live in.

In 2014 it was voted number one university in the UK for Student Satisfaction by Times Higher Education and in the last decade has won four Queen’s Anniversary Prizes in recognition of the outstanding contribution to the United Kingdom’s intellectual, economic, cultural and social life.

Sheffield has five Nobel Prize winners among former staff and students and its alumni go on to hold positions of great responsibility and influence all over the world, making significant contributions in their chosen fields.

Global research partners and clients include Boeing, Rolls-Royce, Unilever, AstraZeneca, Glaxo SmithKline and Siemens, as well as many UK and overseas government agencies and charitable foundations. Imperial College London

Consistently rated amongst the world's best universities, Imperial College London is a science-based institution with a reputation for excellence in teaching and research that attracts 14,000 students and 6,000 staff of the highest international quality. Innovative research at the College explores the interface between science, medicine, engineering and business, delivering practical solutions that improve quality of life and the environment - underpinned by a dynamic enterprise culture.

Since its foundation in 1907, Imperial's contributions to society have included the discovery of penicillin, the development of holography and the foundations of fibre optics. This commitment to the application of research for the benefit of all continues today, with current focuses including interdisciplinary collaborations to improve global health, tackle climate change, develop sustainable sources of energy and address security challenges.

In 2007, Imperial College London and Imperial College Healthcare NHS Trust formed the UK's first Academic Health Science Centre. This unique partnership aims to improve the quality of life of patients and populations by taking new discoveries and translating them into new therapies as quickly as possible.

www.imperial.ac.uk

Contact