Influenza-Related Mortality Among Adults Aged 25-54 Years With AIDS in South Africa and the United States of America

Background. Data are limited on human immunodeficiency virus (HIV)-associated influenza burden in sub-Saharan Africa and the impact of highly active antiretroviral therapy (HAART). We compared influenza-related mortality in adults with AIDS in South Africa and the United States in the pre-HAART era and evaluated mortality trends after HAART introduction in the United States. Methods. Monthly all-cause and pneumonia and influenza (P&I) mortality rates were compiled for adults with AIDS aged 25-54 years in South Africa (1998-2005) and the United States (pre-HAART era, 1987-1994; HAART era, 1997-2005). We estimated influenza-related deaths as excess mortality above a model baseline during influenza epidemic periods. Influenza-related mortality rates in adults with AIDS were compared with rates for age peers in the general population and adults >= 65 years old. Results. In the United States before HAART, influenza-related mortality rates in adults with AIDS were 150 (95% confidence interval [CI], 49-460) and 208 (95% CI, 74-583) times greater than in the general population for all-cause and P&I deaths, respectively, and 2.5 (95% CI, 0.9-7.2) and 4.1 (95% CI, 1.4-13) times higher than in elderly adults. After HAART introduction, influenza-related mortality in adults with AIDS dropped 3-6-fold but remained elevated compared with the general population (all-cause relative risk [RR], 44 [95% CI, 16-121]); P& I RR, 73 [95% CI, 47-113]). Influenza-related mortality in South African adults with AIDS in recent years was similar to that in the United States in the pre-HAART era. Conclusions. Adults with AIDS experience substantially elevated influenza-associated mortality, which declines with widespread HAART introduction but does not disappear. These data support increased access to HAART and influenza vaccination for HIV-infected adults.