Preventive therapy in children exposed to Mycobacterium tuberculosis: problems and solutions.

Young children living with a tuberculosis patient are at high risk of Mycobacterium tuberculosis infection and disease. WHO guidelines promote active screening and isoniazid (INH) preventive therapy (PT) for such children under 5 years, yet this well-established intervention is seldom used in endemic countries. We review the literature regarding barriers to implementation of PT and find that they are multifactorial, including difficulties in screening, poor adherence, fear of increasing INH resistance and poor acceptability among primary caregivers and healthcare workers. These barriers are largely resolvable, and proposed solutions such as the adoption of symptom-based screening and shorter drug regimens are discussed. Integrated multicomponent and site-specific solutions need to be developed and evaluated within a public health framework to overcome the policy-practice gap and provide functional PT programmes for children in endemic settings.