Why the true burden of paediatric TB remains unknown

What James Harrington said is very relevant to childhood TB, and in particular, to those children under five years who are in close contact with an adult who has been recently diagnosed with active pulmonary TB.

After years of neglect, WHO in its recent report — Road map for childhood tuberculosis — has rightly pointed out saying: “the urgency of the problem of TB in children, whose full scope is still not fully known, cannot be underestimated.” In 2012, the global burden of TB in children was estimated to be about 5.3 million; across the world, TB killed about 74,000 last year. But in high-burden settings, the burden could be between 10 per cent and 20 per cent, it noted.

In 2011, the first year when WHO included the estimates of paediatric TB in its annual report, the incidence among children was about half-a-million and the number of people killed was 64,000.

But the actual burden of TB in children is very likely to be much higher, given the fact that diagnosing childhood TB is a big challenge. WHO’s Systematic Screening for Active Tuberculosis report notes: “[Close contacts of a diseased person] has a high likelihood of having undetected TB and a high risk of poor health outcomes in the absence of early diagnosis and treatment.”

“There has been a circular argument concerning childhood TB. Some have said that without evidence of under-diagnosis of TB in children there is no justification for allotting additional resources for diagnosis, treatment and prevention. However, the resources to adequately determine the burden of childhood tuberculosis (the evidence) have not been made available,” said Dr. Jeffrey R. Starke, Professor of Paediatrics, Baylor College of Medicine, Houston, Texas at the recently concluded 44th Union World Conference on Lung Health held in Paris (Click here for Podcast).

Aside from the lack of effective diagnostic tools, even appropriate child-friendly fixed-dose combination drugs for treatment are not available.

While most children, especially those under five years of age, develop the disease within one year of becoming infected, a few others contain the disease and remain well. But the disease rears its head at a later date. According to him, many adult TB cases arise from infection that occurred in childhood.

Apparently, childhood TB serves as a window into the effectiveness of tuberculosis control. “I would argue that childhood tuberculosis is a fundamental indicator of a tuberculosis control programme. If you are trying to control and prevent tuberculosis, probably the number one thing to look at is childhood TB disease,” Dr. Starke emphasised. After all, almost all children aged under five get infected from a family member.

“When you find a case of TB, the incremental expenditure of resources in trying to identify the contacts is not all that great a burden. When we are talking about prevention, we cannot be talking about patient-centric care. We must be talking about family, we must be talking about community. And that is what has been missing,” he said.

The time has come to shift our focus from patient-centric care to family-centric care. USAID has the same views The notion that tuberculosis, the world’s oldest disease, is restricted to adults has been completely shattered, it notes.

The resurgence in the U.S. in the 1980s and 1990s when TB overall went up by 20 per cent makes a strong case for giving greater importance to active case finding through contact tracing of children from households with a diseased adult. “The harbinger of that TB [resurgence in the U.S.] was childhood tuberculosis, with the reported incidence going up by 40 per cent,” Dr. Starke noted.

If over ten million children were orphaned in 2010 as a result of parental deaths caused by TB, how many of these orphaned children have been infected or diseased by tuberculosis? And how many of those aged under five have already died? TB is now among the 10 major causes of mortality among children.

And this brings us back to the question of the level of importance India’s Revised National Tuberculosis Control Programme (RNTCP) gives to childhood TB, and contact screening in particular, in the absence of correct incidence, prevalence and mortality data.

A September 2010 paper in the Infectious Disease Clinics of North America journal states why childhood TB should be taken seriously. “Paediatric TB can be regarded as an emerging epidemic in areas where the adult epidemic remains out of control and Mycobacterium tuberculosis transmission is ongoing,” it notes.

But RNTCP is far from giving paediatric TB its due importance.

A 2009 study published in the International Journal of Tuberculosis and Lung Diseases by V.V. Banu Rekha and others from the Chennai-based National Institute for Research in Tuberculosis (formerly TRC) found that only 14 per cent of child contacts were screened and only 19 per cent were initiated on isoniazid preventive therapy! The study was done in two centres in Chennai and two in rural Vellore district, Tamil Nadu.

Source: The Hindu