Mother to child transmission of HIV in China

As the number of people with HIV infection increases in China, the potential for the epidemic to spread from high risk groups to the general population, including children, is a concern. An estimated 840 000 adults and children (a prevalence of 0.1%) were living with HIV in China in 2003.¹ That number may approach 10 million by 2010 if the current trends persist.² An HIV prevalence of over 1% among pregnant women has been considered an indicator of a generalised epidemic.³ Whether that rate is currently being seen in any parts of China is of great public health importance. Here we review the current state of mother to child transmission in China.

The most common modes of HIV transmission have been sharing of contaminated needles among intravenous drug users in southern and western China, unsafe blood collection in central China, and unsafe sexual practices among commercial sex workers, men who have sex with men, and migrant workers.⁴ The potential for HIV infection to spread from commercial sex workers to their clients and then to the clients' steady partners is highlighted by a report on chlamydial infection in the general Chinese population.⁵,⁶ The heterosexual transmission of HIV from infected blood donors and infected blood recipients to their steady partners may also fuel the epidemic.⁷ Thus, many women may become infected with HIV with the potential for subsequent mother to child transmission.

In 1995, the first case of mother to child transmission was reported to the Chinese Center for Disease Control and Prevention in Yunnan province. Since then, data from China HIV and AIDS case reports have shown a small number of cases: 3-4 in 1997-9, 10 in 2000, 32 in 2001, and 41 in 2002.⁸ However, the proportion of reported cases of HIV and AIDS attributed to transmission from mother to child has increased from 0.1% in 1997 to 0.4% in 2002. Studies have shown a high prevalence (30-38%) of HIV infection among children born to HIV infected mothers in certain areas of China.⁹,¹⁰

In 1995, China's government established a national sentinel surveillance system to monitor trends in HIV and AIDS in four target groups: clients of sexually transmitted infection clinics, commercial sex workers, intravenous drug users, and truck drivers. In 1997, the first sentinel site for pregnant women was set up in Yining city, Xinjiang province. Since then, additional national and provincial sentinel sites have been established.

To obtain the most recent estimate of HIV prevalence among pregnant women in China, we abstracted information from HIV sentinel surveillance reports from the eight provinces with national and provincial sentinel sites. As of 2003, 18 national sentinel sites for pregnant women were set up in eight provinces. The geographic distribution of reported HIV/AIDS cases and national sentinel sites in pregnant women in China are depicted in the figure. In 2003 the average HIV prevalence among pregnant women in the eight provinces of China with national and provincial sentinel sites was 0.4% with a range from 0% to 1.4% (see table on bmj.com).

As two provinces in China have HIV prevalence in pregnant women of over 1%, preventing further HIV infections through heterosexual transmission is an urgent priority. Pilot interventions have been developed by the ministry of public security and the ministry of health to promote the use of condoms at places of entertainment.⁸

Prevention of mother to child transmission is also an imperative, especially since use of antiretroviral therapy for the mother during pregnancy and for the infant after birth is an effective measure. Efforts to prevent transmission in China are under way, and China's government has mandated that they be scaled up rapidly. In 2002, the ministry of health and Chinese Center for Disease Control and Prevention joined with Unicef to conduct a programme in Henan province. Voluntary counselling and testing were provided by the health ministry in other areas to facilitate pilot work.⁸ In addition, under the guidance of the ministry of health, the division of maternal and child health (affiliated with the Chinese Center for Disease Control and Prevention) are enrolling women from Guang-dong, Guangxi, Henan, Xinjiang, and Yunnan provinces to find effective strategies.¹¹ In 2004 the ministry of health published guidelines to prevent mother to child transmission, addressing issues of testing for HIV infection, provision of antiretroviral treatment, and infant feeding.¹²,¹³

China currently has few HIV cases related to mother to child transmission and an overall low prevalence of HIV infection in pregnant women. However, two provinces in China have HIV prevalence rates in pregnant women in excess of 1%, a rate that is indicative of a generalised epidemic. Efforts to prevent heterosexual transmission of HIV and mother to child transmission are underway in areas of increasing HIV prevalence in adults. The course of the HIV epidemic in China should be easier to discern over the next few years.