This report is a summary of the first two rounds of national surveillance of behavioral and biological data among those believed to be most likely to contract or transmit HIV and STIs in Laos. The first round was conducted in 2000–2001 and the second in late 2004.

The data in this document describe trends in knowledge and self-reported risk behavior related to HIV and STIs among survey subjects. In addition, biological specimens were collected (with informed, voluntary consent) to measure levels and trends of common STIs and HIV. Together, these two rounds of data present the most accurate picture to date of Laos' risk profile for HIV/AIDS. The data also suggest the impact of prevention activities during the four-year interval between rounds.

We hope these data will inform future HIV/STI prevention program planning. In addition, these data may help track the progress of Laos' national HIV/STI prevention and control program.