systematic review National Center for Biotechnology Information NCBI NLM MEDLINE review humans pubmed abstract nih national institutes of health national library of medicine research support non-u.s. gov't Child Infant preschool risk factors hiv infections / complications* risk assessment practice guidelines as topic aids-related opportunistic infections / microbiology tuberculosis / prevention & control* aids-related opportunistic infections / prevention & control* pmid:19861003 p azzopardi c m bennett t duke aids-related opportunistic infections / etiology* aids-related opportunistic infections / mortality bcg vaccine / adverse effects* mycobacterium tuberculosis / pathogenicity* tuberculosis / etiology* tuberculosis / microbiology tuberculosis / mortality