MSH Research Contributes to Addressing TB in Children
MSH Research Contributes to Addressing TB in Children
by Barbara K. Timmons
Globally, more than 230,000 children died of TB in 2019. According to the World Health Organization (WHO), children under the age of 14 accounted for 12% of the people who developed TB in that year. In any given year, millions of children are infected with TB, which affects especially the most vulnerable, such as those who are malnourished. This tragedy is made worse because TB tends to be difficult to diagnose in children, and they are more likely to develop serious forms of TB. Many cases of childhood TB are missed, and access to services has been further compromised by the COVID-19 pandemic.
The good news is that TB is preventable and curable in children, just as it is in adolescents and adults. Vaccination with the bacille Calmette-Guérin (BCG) vaccine can protect children, especially from severe forms of TB. Treatment with isoniazid, an antibiotic first manufactured in 1952, is also effective in preventing the development of active TB disease in children, and others who are in close daily contact with someone who has TB. However, the percentage of household contacts who are children under five who received TB preventive treatment in 2018 and 2019 represented only 21% of the target for the period 2018-22.
Among children with active TB disease, only about 500,000 were treated for TB in 2019, although new pediatric medicines and child-friendly formulations are easier for parents to give and more palatable for children. The global treatment success rate for children has reached 85%.
Successfully treating children with TB in Ethiopia
Two recent peer-reviewed journal articles led by MSH contribute to addressing critical gaps in the diagnosis and treatment of tuberculosis (TB) in children. A study led by MSH’s Dereje Habte looked at factors determining treatment success in children with drug-sensitive TB in two large regions of Ethiopia, one of the countries with the highest TB burden worldwide. Of 2,557 children registered, 1,218 (48%) had clinically diagnosed pulmonary TB, 1,100 (43%) had extrapulmonary TB, and 227 (9%) had bacteriologically confirmed TB, while 12 lacked records. The treatment success rate was high, at 92%, and the death rate was 3%. Multivariate analysis showed that being older than five, enrolled in directly observed treatment in a health center, and HIV negative were predictors of treatment success, while underdosing during the intensive phase of treatment was associated with treatment failure. The authors recommend more research to determine if intensive monitoring of children with TB, dosage adjustment of anti-TB drugs based on weight changes, and training of health workers on dosing might improve treatment outcomes.
“Faster progress towards the targets set at the UN high-level meeting will require action on various fronts. Examples include better case detection through active contact investigation, increased use of WHO-recommended diagnostics on easier to-collect specimens from children . . . and building capacity in the clinical diagnosis of TB in children. . . . Coordination and integration with primary health care, and with maternal and child, nutrition, and HIV programmes are crucial” (WHO).
Diagnosing TB among children in Afghanistan
Another MSH team studied household contact screening for TB and the provision of isoniazid preventive therapy (IPT) to under-five aged children in Afghanistan. This study analyzed the performance of the National TB Control Program in Afghanistan in household contact screening from 2011 to 2018 and its use as an entry point for IPT, as well as the IPT completion rates for children under age five. From 2011 to 2018, 142,797 bacteriologically confirmed TB cases were diagnosed in Afghanistan. Out of all children under five who had household TB contacts, 101,084 (86%) were initiated on IPT and 69,273 (69%) completed treatment. Program performance in contact screening in Afghanistan is high, at 81%, and the yield of TB (defined as the number of new TB cases diagnosed per contact screened) is also high—close to 10 times higher than the national TB incidence rate. IPT initiation and completion rates are also high compared to those of many other countries but need further improvement, especially for completion.
Data from these two studies show that good results are possible even in resource-constrained countries, if local capacity is systematically built in the health system. This capacity should include counseling of TB patients to bring their children in for screening and adhere to IPT to make sure that children complete treatment.
MSH continues the fight against TB in Ethiopia and Afghanistan as the lead partner in USAID's Eliminating TB Project and the USAID-funded Assistance for Families and Indigent Afghans to Thrive (AFIAT) Program. As a key member of the consortium implementing Challenge TB, TB CARE I, and TB CAP from 2005 through 2019, MSH has led TB programs in Afghanistan, Bangladesh, Ethiopia, Ghana, and South Sudan, and worked closely with National Tuberculosis Programs in Cambodia, Democratic Republic of the Congo, Indonesia, Kenya, Mozambique, Namibia, Nigeria, Tanzania, and Vietnam. MSH has also led bilateral USAID TB programs in countries that include Ethiopia and Uganda.