Two previous studies of an HIV preventive vaccine, the STEP study and the Phambili study, were halted because people who received the vaccine were more likely to become infected with HIV. Why this vaccine failed is still being researched, but one reason may be related to the recombinant Adenovirus type 5 (rAd5) virus vector used in the vaccine. Two trials of another HIV preventive vaccine that used a rAd5 virus vector were conducted in Uganda. This study will obtain follow-up safety information on participants in those trials.