Characterizing the HIV/AIDS Epidemic in the United States and China.

The HIV/AIDS data from the national surveillance systems of China and the United States from 1985 to 2014 were compared to characterize the HIV/AIDS epidemic in both countries. The current estimated national HIV prevalence rate in China and the United States are 0.0598% and 0.348%, respectively. In the United States, the annual number of new HIV infections has remained relatively stable (~50,000 each year) and has shown a downward trend in recent years. The Chinese national HIV prevalence is still low, and new HIV infections have been contained at a low level (50,000-100,000 each year). However, the epidemic has showed an increasing trend since 2012. By risk group, in both countries, men who have sex with men (MSM), heterosexual sex, and injection drug use (IDU) are the most common modes of transmission of new HIV infections. However, in the United States, MSM is the dominant transmission route, accounting for >60% of new infections; whereas in China, heterosexual sex has now become the dominant route, also accounting for >60% of new infections. A rapid increase in the proportion of HIV cases that were attributed to MSM and an obvious decrease in the proportion of HIV cases attributed to IDU in China in recent years imply that the China's epidemic is still evolving, to some extent, copying what was experienced in the United States. By age group, the proportions of HIV cases that were attributed to the age group 25-59 were comparable between the two countries. However, the United States had a higher proportion of cases that were attributed to age groups 15-19 and 20-24 than China, indicating that youth account for more infections in the United States. One other fact worth noting: in China there is a significant increase in the number of HIV new infections in individuals over 50 years of age, which results in much higher proportion of cases that were attributed to age groups 60-64 and over 65 in China than those in the United States. By race/ethnicity, in the United States, Blacks/African Americans continue to experience the most severe HIV burden, followed by Hispanics/Latinos. In China, no official data on race/ethnicity disparities are currently available. Thus, region, risk group, age are important factors in the HIV epidemics in both countries.