Hiv Infection among Pregnant Hilltribe Women

A case-control study was carried out to determine factors associated with HIV infection among pregnant hilltribe women who attended the antenatal clinics of six hospitals in northern Thailand (Mae Suai, Wieng Pa Pao, Mae Sai, Mae Chan, Wieng Kaen, Mae Fa Luang, and Chiang Rai hospitals) between 1 January 200531 May 2007. Data were collected using questionnaires and analysis was by univariate (p-value=0.100) and multivariate analysis (pvalue=0.050) in the model of unconditional multiple logistic regression. The ratio of cases to controls was 1:4. The sample consisted of 255 subjects; 51 cases and 204 controls. The mean age of the women was 26.9 years (min=15, max=52, and SD 7.3). The majority of the women were Lahu (49.8%) or Akha (36.9%). Nearly half the women were Christian (48.2%), followed by Buddhist (42.4%). Most of the women were not educated (60.4%). The largest group for family income was 10,000-49,999 baht/year (62.6%). After controlling for family income, family debt, education, occupation and household members, the findings showed that the “not married to debut partner” group were at greater risk than the “married to debut partner” group by 6.6 times (ORadj =6.6, 95%CI=2.9-14.9). The “use of alcohol” group were at higher risk by 4.5 times (ORadj =4.5, 95%CI=2.0-10.3) compared to the no alcohol use group, and a history of genital ulcer group had an increased risk of 6.3 times (ORadj =6.3, 95%CI=1.231.1) the chance of having HIV infection compared to no history of genital ulcers in pregnant hilltribe women. The number of people living with HIV has increased in all regions of the world. The AsiaPacific region (WHO, 2005) is home to 60% of the world’s population; 19% of them were living with HIV in 2004, 5.2 million men, 2 million women, and 168,000 children. For each adult woman living with HIV in the Asia-Pacific region, four men were living with the virus in the same region. In Asia, 8.6 million people were living with HIV in 2006 (UNAIDS/WHO, 2006), including 960,000 people who became newly infected in 2006. Approximately 630,000 died from AIDS-related illnesses in 2006. In Southeast Asia, although HIV prevaINTRODUCTION It has been more than 25 years and 25 million deaths since the first case of AIDS was diagnosed. In 2006, the WHO/UNAIDS estimated that 39.5 million men, women and children were living with the human immunodeficiency virus (HIV). Globally 2.9 million people had died, of which nearly half were children. Close to 4.3 million people were newly infected with the virus in 2006. SOUTHEAST ASIAN J TROP MED PUBLIC HEALTH 1062 Vol 38 No. 6 November 2007 lence is still low, it is one of the most rapidly growing HIV/AIDS epidemics globally, because of the presence of several factors that enhance the spread of HIV, including poverty, gender inequality, and social stigma. In 2006 an estimated 7.8 million people were living with HIV/ AIDS, while < 10% of infected persons were aware of their HIV status. At the end of 2005, an estimated 580,000 people were living with HIV/AIDS in Thailand. Approximately one third of new infections in 2005 were in married women who probably were infected by their spouses (UNAIDS/WHO, 2006). In Thailand, the first reported AIDS case was a Thai student returning from the USA, who died in 1984, this case had a homosexual risk factor (Wangroongsarb and Wasi, 1985). Rapid spread of HIV-1 was noted among injecting drug users in 1987 (Kitayaporn et al, 1994), and in the female commercial sexworkers in 1989 (Siraprapasiri et al, 1991). The prevalence of HIV was highest in northern Thailand, with approximately 50/100,000 population (Sirisopana et al, 1996; MOPH, 2005). Northern Thailand along the upper North, the Myanmar border, and some coastal regions had the highest seroprevalence of HIV (Dobbins et al, 1992; Sirisopana et al, 1996; Kitsiripornchai et al, 1998). The highest number of HIV/AIDS cases was in Chiang Rai Province (MOPH, 2004). Hill tribes are comprised of about 20 ethnic groups living in northern Thailand, bordering Lao PDR and Myanmar. The hill tribes together number approximately 550,000 people (Department of Social Welfare, 2001). Most of them migrated to Thailand from Tibet, China, and Myanmar in the 19th and 20th centuries. The main groups are the Mien (Yao), Karen (Gariang), Akha (Egaw), Lahu (Mursay), Hmong (Meo), and Lisu (Lisaw). Chiang Rai has the second largest number of hill tribes consisting (Department of Social Welfare, 2001) of six main hilltribe groups: Akha, Lahu, Karen, Lisu, Hmong, and Yao. Hilltribe people are living in HIV epidemic areas in northern Thailand, therefore they may be particularly vulnerable to HIV infection. Little is known about sexual risk factors and sexual practice of hilltribe people. The accelerating commercialism of Thailand and the gap in earning potential between rural and urban areas have motivated some hilltribe people to move to urban areas for financial reasons. It has been estimated the 70-90% of young hiiltribe women are sexually active before marriage (Cash, 1999). In most hilltribe cultures, there is gender inequality and women are often not in a position to negotiate safe sex, and putting them at risk for infection from husbands and partners (Morison, 2001). Hilltribe women (Bayrer, et al, 1997) appear to be at risk for HIV infection at a younger age than men; the highest rate of HIV infection was among women 20-24 years old (3.9%). There is an urgent need to identify risk factors, such as polygamy, sexual culture, and labor migration. In Thailand, the proportion of women giving birth who receive antenatal care is very high. In 2001, of 573,655 women who gave birth in Thailand, 554,912 (96.7%) received antenatal care, and 517,488 (93.3%) were tested for HIV before giving birth (Amornwichet et al, 2002). To date, no research has studied the relationship between HIV/AIDS infection in hilltribe people and their current social and sexual behavior, and sexual practices in both women and men, or the conflicts between “traditional” and “modern” values. The economic migratory movements of hilltribe people may increase their risk for infection. One study objective was to use pregnant women as a model to study risk factors for HIV/AIDS in northern hilltribe people and the socioeconomic effects of the infection on them. MATERIALS AND METHODS This study was of case-control design. HIV INFECTION AMONG PREGNANT HILLTRIBE WOMEN Vol 38 No. 6 November 2007 1063 The study sites were 7 antenatal clinics in Chiang Rai Province, Thailand; Chiang Rai, Mae Chan, Mae Suai, Wieng Pa Pao, Mae Fa Luang, Wieng Kaen, and Mae Sai. The target populations were pregnant women from 6 hilltribes (Akha, Lahu, Lisu, Yao, Hmong, Karen) living in Chiang Rai Province. The study population was hilltribe women who were pregnant and lived in Chiang Rai Province, Thailand. Cases and controls were recruited from antenatal clinic (ANC) logbooks. Two rapid HIV tests, or an enzyme-linked immunosorbent assay (ELISA) were used to identify cases with positive results (WHO, 1988). All cases and controls in the study were pregnant hilltribe women attending one of the 7 hospital ANCs at least once from 1 January 2005 to 30 March 2007. The cases were selected by collecting all positive women from 1 January, 2005, until 51 cases had been collected. Controls were obtained by simple random sampling from the ANC logbook in each 3-month interval from the same clinics as the cases. The ratio of cases to controls was 1:4. Therefore, the controls numbered 204 samples.