Age, occupation, trimethoprim-sulfamethoxazole prophylaxis, history of pneumonia, history of tuberculosis, body mass index, habit of mouth washing and brushing, recent CD4 T cell counts and viral load, smoking habits, WHO HIV stage, alcohol consumption, and interruption of ART were significantly associated with bacterial pneumonia according to the bivariable logistic regression analysis done and hence were further subjected to multivariable logistic regression analysis, as candidate variables to control the confounding effect (Table 5). This evidence concerns the gene CD4 and bacterial pneumonia.