The number of reported HIV cases in China remains relatively small for its size, according to the World Health Organization, but there are signs the problem could become an epidemic. The clue comes from a new study showing that China has high rates of another sexually-transmitted disease considered a forerunner of HIV spread - chlamydia.
Interviews and urine samples from 3,400 Chinese volunteers aged 20 to 64 reveal that the curable, often symptomless genital infection chlamydia has reached, on average, two percent of Chinese men and 2.5 percent of Chinese women. It is much worse in cities where eight percent of women have the bacterial infection. In the rapidly developing coastal south, chlamydia infects 16 percent of men and 10 percent of women.
Study leader William Parish, a University of Chicago sociologist, said the rates are high compared to other nations. "We find that chlamydia rates are three to six percentage points higher than developed countries. Even in the countryside, the chlamydia rates are similar to what we find in some parts of Africa. Both those sets of findings are alarming," Mr. Parish said.
The worry is not only about chlamydia itself, but also for what it portends. The researchers say that the high prevalence of the infection in China signals the possible paths HIV will take as it moves into the mainstream population.
"It gives an indicator of what will happen in years to come as HIV begins to spread through sexual networks in China, and suggests that without a major new public health campaign in China, they would soon have a major problem on their hands," Mr. Parish said.
The study, which appears in the Journal of the American Medical Association, shows that the chlamydia epidemic is concentrated among Chinese prostitutes and high income men who use them, and transmit the infection to their wives and other sex partners. This hints at where a future HIV epidemic would hit.
The U.S. researchers and their colleagues from Renmin University and Peking Union Medical College recommend campaigns aimed at Chinese prostitutes and their clients to increase AIDS awareness and condom use. Johns Hopkins University physician Chris Beyrer wrote an editorial accompanying the study saying there is little time to waste.
"Now is the time for China to implement a safer sex program targeting this commercial axis because we've seen before both in Thailand and Cambodia that this can be a very efficient way for HIV to move from high-risk populations into much broader populations. And that's what nobody wants to see in a population the size of China's," he said.
But are Chinese health officials ready to do this? Dr. Beyrer, Mr. Parish, and the World Health Organization all say that information campaigns are sparse and the average Chinese person's knowledge of how to prevent HIV infection is low. Moreover, Dr. Parish notes that, because prostitution is illegal, it might be politically difficult for the government in Beijing to recognize sex workers for special health measures.
"It's a long way from it. The WHO is running a few test campaigns in a very small number of districts of cities in China and we don't have the results of that yet. It takes a major new political will and it takes new budgetary resources, and that's difficult in China just as it is everywhere in the world," Dr. Parish said.
Dr. Chris Beyrer agrees that progressive AIDS policies are tough to implement, but adds that the window of opportunity in China is narrow and closing.
