The TB Crisis in Children. 17/11/10
The Global Center’s David Bryden reported from the 41st Union World Conference on Lung Health, last week in Berlin.
Tuberculosis is often thought of as a disease that mainly affects adults. However, at the Union World Conference on Lung Health in Berlin, Dr. Anneke Hesseling of the Desmond Tutu TB Centre in South Africa presented some startling information showing that the level of infection among children is actually quite significant, and that TB is an important issue for maternal and child health advocates.
I spoke with Hesseling about the issue on the sidelines of a session in Berlin devoted to “Critical Issues in TB Clinical Trials,” where she gave a talk with slides about the urgent need for more research for medications to address TB in children. Her talk is available online, as are several other presentations on children, including a talk by the CDC’s Heather Menzies on how TB can be prevented in children with HIV.
“The case burden is much larger [in children] than people realize,” Hesseling said.
In South Africa, more than 16 percent of all TB cases are children. The same percentage exists in Uganda, Tanzania and Zimbabwe. The problem is not limited to countries with high HIV/AIDS prevalence. In Pakistan, 61,905 cases, or more than 25 percent, are children.
Yet Hesseling said the problem may be much larger than shown by the available statistics, and with the new diagnostic technology, many more cases might be found.
With proper case detection it would be shown that globally at least 15 to 20 percent of TB cases are children, according to Hessling. She said that once people are trained in how to detect TB in children, even using the currently inadequate diagnostic methods, there is a big jump in the proportion of cases found among children, from 2 percent up to 15 percent.
The situation demands urgent attention, especially since children who are infected tend to develop disease much more rapidly than adults. “Children develop quite severe forms of TB, including TB meningitis,” Hesseling said. Young children and children with HIV are especially vulnerable. In the area of South Africa where Hesseling works, about 25 percent of the children with TB are HIV-infected, however in areas such as Johannesburg and KwaZulu Natal the figure is more like 60 to 70 percent.
“What is really an enormous tragedy is that TB in many of these cases in children is preventable, but the guidelines to do so are not being followed,” Hesseling said, adding that most children with TB are contracting it at home from adults.
“The guidelines say that health care providers should ask adult TB patients if there are children in their household, do contact tracing and then provide vulnerable people, including children, with Isonaizid Preventive Therapy (IPT). IPT is safe and cost effective, but this is not happening, in part due to weak health system capacity.”
There is an urgent need for better diagnostics that can detect TB in children, including using a blood, urine or a stool sample, Hesseling said. “We need to see more lobbying to call for tests that are relevant for children.”
The sputum culture can diagnose only 30 to 40 percent of TB cases in children, and only about ten to 15 percent of children are smear-positive (which helps establish an immediate diagnosis). The diagnosis of TB in children thus often relies on the clinical history and examination plus tests such as the tuberculin skin test and x-rays, which are less reliable.
One initiative to help push diagnostic development forward is a collaborative, World Health Organization (WHO)-sponsored effort called the Diagnostic Evaluation Expert Panel, an initiative of the Special Program for Research and Training in Tropical Diseases which has identified pediatric TB as a neglected disease. The partners involved will be publishing model protocols and tools to standardize measures for appropriate tests as a part of an open-source, non-academic website, to foster innovation and more uniform reporting of childhood TB and care for patients. Hesseling provided summary of the expert panel’s conclusions.
“Something like the GeneXpert test is really very exciting, and it is being evaluated in children. We need to sort out many issues to understand its potential impact, since we need to pay attention not just to the accuracy of the test but also its implications, including cost and impact on clinical management,” Hesseling said.
Addressing TB in children is an important opportunity for health program integration, Hesseling continued, since it is an issue that affects both mothers and children. “We have added a fourth ‘I’ to the three ‘I’s’ of TB prevention and control, that of integration,” she said, adding that routine screening for TB during routine antenatal care is an important strategy for maternal/infant health interventions.
Asked about pneumonia among children, Hesseling said that while TB in children is relatively rare compared to pneumonia, “the idea is not to distract from preventing and treating other infectious diseases like pneumonia, but in fact the funding for TB in children allows us to increase health services, and for lung health issues, for children in general. These are not competing diseases, but in fact we can use these issues to link up programs and increase funding, even benefiting pneumonia programs.”
The social determinants of health are also important, according to Hesseling. Improving nutrition in the family, decreasing smoking among adults and addressing poverty will also help tackle the social factors that foster TB.
Awareness of the problem of childhood TB has increased tremendously in recent years. “When I first came to a Union meeting nine years ago only five people came to the pediatric TB discussion, yet now we have 80 people attending the pediatric interest group,” Hesseling said. ”We are in an exciting time in the field.”