Contact tracing and isoniazid preventive therapy for prevention of childhood tuberculosis in The Gambia

Egere, Uzochukwu Emeka (2017): Contact tracing and isoniazid preventive therapy for prevention of childhood tuberculosis in The Gambia: an analysis of the challenges and opportunities. Dissertation, LMU München: Medizinische Fakultät

Abstract

Background Tuberculosis is a major public health problem worldwide and is characterized by a high incidence in The Gambia. Children acquire infection primarily from adults in their households, and especially young children are at higher risk of progressing to disease and death. In The Gambia, childhood tuberculosis is poorly addressed in the routine national TB program activities; contact tracing and isoniazid preventive therapy (IPT) are not implemented. The burden of childhood TB is therefore poorly characterized and the operational challenges of implementing IPT are not well understood. Methods TB symptoms screening questionnaire and tuberculin skin testing were administered in the community to child contacts of adults recently diagnosed with TB. Those with TB suggestive symptoms and/or positive TST result were further evaluated in a dedicated clinic with physical examination, chest x ray, sputum induction and examination with smear, Xpert MTB/RIF and culture. Adherence to IPT was measured by pill count and IsoScreen test. Results Co-prevalent TB disease was detected in child contacts both within and outside immediate household of the adult index TB case. Altogether, 1.6% of all child contacts screened had co-prevalent TB disease. 42.2% of the co-prevalent TB cases were among asymptomatic but TST positive child contacts. A combination of Xpert and culture was positive in 32.3% of all children diagnosed with TB, an increase of 9.7 – 22.6% over the yields from microscopy, Xpert and culture alone as individual tests. 255/328 (77.7%) children completed each of six months of IPT with good adherence. Conclusions Contact tracing restricted to symptom screening and immediate households would have missed nearly half of all co-prevalent TB disease in child contacts in this setting. A combination of Xpert and mycobacterial culture had incremental benefit for the bacteriological confirmation of TB disease in actively traced child contacts. Uptake of, and adherence to, IPT were high among the eligible child contacts.

• Dokumententyp: Dissertationen (Dissertation, LMU München)
• Keywords: childhood tuberculosis, contact tracing, isoniazid preventive therapy, adherence, confirmed tuberculosis, symptom screening
• Themengebiete: 600 Technik, Medizin, angewandte Wissenschaften ; 600 Technik, Medizin, angewandte Wissenschaften > 610 Medizin und Gesundheit
• Fakultäten: Medizinische Fakultät
• Sprache der Hochschulschrift: Englisch
• Datum der mündlichen Prüfung: 3. April 2017
• 1. Bericht­erstatter:in: Hoelscher, Michael