AIDS in China - 1 Mother-to-Infant HIV Transmission: Its Status, Crisis and Countermeasures

1. Situation of Mother-to-Infant Transmission of HIV 1 Worldwide

HIV/AIDS has become a major cause of death for children around the world. In 90 percent of the cases, HIV is transmitted from mother to child. It was estimated that 2,400,000 HIV-infected women gave birth, creating 600,000 HIV-infected babies every year. Everyday, 1600 newborns are infected with HIV. In Africa, infant mortality rose by 75 percent and child mortality increased by 100 percent because of HIV infection. In Uganda, 34 percent of its HIV-infected children died before reaching the age of one, 66 percent died before three, and 75 percent died before five. HIV/AIDS has created more than 11 million orphans who lost both parents. HIV is primarily a sexually-transmitted disease. Developing nations are most vulnerable to its threat. In Africa, HIV has been running rampant for quite some time. In many areas, more than 20 percent of the pregnant women have been infected already. Most children were infected during birth or breast feeding. Very few were infected in the uterus. The HIV-1 transmission rate in the perinatal period is 20 to 42 percent [1]. In developing nations breast feeding is an important risk factor in the vertical transmission of HIV-1. The infection rate is substantially higher in developing nations than that in industrialized countries.

In recent years, it is possible to block mother-to-infant HIV transmission by drugs, especially in western industrialized nations. With long-term use of AZT and formula feeding, the mother-to-infant HIV-1 transmission rate has fallen to less than 5 percent. Since 1992, clinical trials began in the United States and France according to Protocol PACTG 076. AZT was given starting from 14 to 32 weeks of pregnancy. The drug was administered intravenously during childbirth. The newborn was also given the drug for six weeks. This protocol lowered the mother-to-infant HIV transmission rate by 67 percent [2]. Afterward, a short-term AZT protocol was also found to be successful [3]. In a recent joint study carried out by Uganda and the United States, a few units of nevirapine (NVP) was given to pregnant women during labor and to newborns less than three days old. This protocol was found to have reduced perinatal HIV-1 transmission rate by 47 percent. (This is equivalent to the effect of the short-term of AZT.) According to a cost estimate made by a drug manufacturer, the entire protocol costs less $4 [4]. This is great news for developing nations.

2. Female HIV-Infected Patients in China

Among adults in China, HIV-1 is primarily transmitted through intravenous (IV) injection of illicit drugs, unprotected sex, and illegal blood trade. Let us take Yunnan as an example. Between 1989 and 1994, HIV-1 infection was confined to IV drug users in the southwestern border. It began to spread across the province in 1995. Between 1986 and the end of 1998, a total of 580,036 people were put under surveillance, and 5,604 were found to be HIV-1 positive. Among these people, there were 854 females. They represented approximately 15 percent of the total. As for the vehicle of infection, 65 percent came from needle-sharing, and 23 percent from sexual transmission [5]. The Guangxi Zhuang Autonomous Region in southwestern China is an area widely open to the outside world. Since AIDS monitoring began in 1986 until 1995, only 10 cases of HIV-1 positive patients were found. They were either foreigners or people from outside the region. However, since the first discovery of HIV-1 infected patients among drug addicts in western Guangxi in April 1996, the rate of transmission has accelerated noticeably. By the end of 1999, a cumulative total of 1175 HIV-1 positive cases were discovered, and 16.1 percent of them were females. This figure is higher than those in other provinces in China. Among the HIV-positive patients, 76 percent were infected were IV drug users. In this category, 20.8 percent were women. This is the highest percentage in China. In addition, these IV drug users sexually transmitted the virus to their spouses and partners. Most of these female IV drug users had multiple sex partners or were engaged in prostitution.

Prostitution is on the rise from cities to the countryside. Venereal diseases, eradicated in the 1960s and 1970s, are spreading across China at an unbelievably high speed. The total number of venereal disease cases across the country reached 358,324 in 2000. Compared to 1997, it increased by 87.53 percent. It is 28.5 times of that in 1987, as shown in Table 1. The rapid rise of commercial sexual behavior and venereal diseases not only negatively impacts the physical and mental health of young women, but also helps the transmission of HIV. According to surveys of customers of prostitutes done in Yunnan, no HIV infected patient was found between 1995 and 1997. In 1998, the HIV infection rate was 0.3 percent. In 1999, it went up to 1.1 percent, which represented a 266.7 percent increase over one year. Among the prostitutes, there was no HIV infected person between 1992 and 1994. In 1995, the HIV infection rate was 0.5 percent. In 1999, it went up to 2.2 percent. At this rate of increase, it was estimated that the infection rate would reach 5.4 percent in 2003 [6].

Table 1 Female Venereal Disease Cases in China Between 1977 and 2000

3. Status of Mother-to-Infant HIV Transmission in China

In 1992, there were two monitoring stations for pregnant women in Yunnan, and they were confined to the Dehong area. It grew to five in 1996. By 1998, it increased to 10, covering nine different areas, as shown in Table 2. The number of women and their spouses infected with HIV is rising. In 1999, the average HIV-1 infection rate for pregnant women was 0.2 percent (see Table 3). The first case of mother-to-infant transmission of HIV-1 in Yunnan was reported in 1995. To date, a total of 46 HIV-1 positive pregnant women have been discovered. Among the 52 newborns, 15 were infected with the HIV-1 virus (out of 42 children tested), as shown in Table 4. A rough estimate based on figures such as population, birth rate, and mean HIV infection rate for 1998 and 1999, at least 1500 pregnant women and 500 newborns were infected by the HIV virus annually [5, 6]. In Xinjiang, IV drug users account for 97 percent of its HIV infected population. Women represent 8 percent of the total. The first case of mother-to-infant transmission was reported in 1996. The baby died in 17 months [7, 8]. In 1999, 1200 pregnant women visiting OB/GYN clinics and admitted to hospitals were tested in Wulumuqi, and six of them were found to be HIV-1 positive. The rate of infection was 0.5 percent. In five cases, the virus was sexually transmitted. The remaining case was due to a tainted blood transfusion [9]. Between 1997 and 1999, a total of 22 HIV-1 positive pregnant women were found at monitoring sites and hospitals in Yili. This is on top of the six cases discovered in Wulumuqi. In most cases, the outcome of the newborns was not known. In 1998, three children from Anhui and Guangdong were tested positive for the HIV-1 antibody according to international adoption agencies, as shown in Table 5. Although additional rigorous tests eliminated the possibility of HIV-1 infection, it is obvious that their mothers were infected with the HIV-1 virus.

Table 2 Number of Monitoring Sites Detecting HIV-1 Positive Pregnant Women in Yunnan Between 1992 and 1999