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Frerichs, R.R. Preventing Mother-to-Child HIV Transmission in Thailand.

SEA-AIDS Network, November 4, 1998.

R.R. Frerichs Posting

More good news is coming from Thailand on ways to reduce mother-to-child HIV transmission. Rather than debating endlessly about the merits and difficulties of saving young children from viral infection, officials in the Thai Ministry of Public Health and their foreign colleagues from Harvard and UNAIDS decided to act, and now have interesting findings to share with others in Asia (see below). The title of their article speaks clearly of the path that public health officials have followed. The process starts with efficacious studies in the research literature. Such investigations demonstrate that a procedure or process works in an optimum settings where extraordinary care and effort is possible and expected. Regarding mother-to-child transmission, two such studies have been widely cited.

The first appeared in 1994 and demonstrated that a costly regiment of AZT (or zidovudine) could dramatically reduce the movement of the virus from mother to child, and the second appeared in 1997 and showed that a less expensive regiment of AZT was also effective. Now the Thailand group has reported the next step, seeing if studies done in perfect settings are feasible and effective in the real world where testing programs must first identify HIV positive women and treatment must be accepted and used over time by those who are infected (i.e., going from efficacy to effectiveness).

What this study also points to is the pathway from problem recognition to experimentation to regional demonstration and eventually to national implementation. In Thailand, problem recognition came from their model HIV sentinel surveillance program, established in 1989 to describe the emerging epidemic. They were able with their epidemiological tool to mobilize the nation and solicit the assistance of the international community to address the epidemic. Yet they also recognized that description with no action leads only to despair, and that field experimentation is needed to generate hope and eventually success and satisfaction.

The Thais saw early on that rigid prescriptions would not halt the spread of the virus in their country. They opened their minds to innovation, being willing to consider views that had any chance of success. Such openness is now being rewarded, offering promise to ordinary people in Thailand who look to the public health community for guidance and assistance.

A nice lesson for others in the region to follow.

Source: Thaineua V, Sirinirand P, Tanbanjong A, Lallemant M, Soucat A, and Lamboray J-L. From efficacy to effectiveness: routine prevention of mother-to-child HIV transmission by a short course of zidovudine in Northern Thailand. South East Asian Journal of Tropical Medicine and Public Health, September, 1998.

Abstract: The Phayao province in northern Thailand (population 517,000) has been severely affected by HIV. Despite the remarkable progress northern Thailand has made in battling this epidemic, as evidenced by decreases in HIV prevalence and changes in sexual behavior, in Phayao in 1997 approximately 280 HIV+ pregnant women, or five percent of the population of pregnant women, gave birth to an estimated 70 infected children. As many of these infants die within their first year of life, the infant mortality rate (IMR) is on the rise again after years of decline. The province, however, has responded quickly to this crisis.

As of July 1997, the Ministry of Public Health (MOPH) has been offering through Phayao's seven public hospitals a short regimen of zidovudine (ZDV) to all consenting HIV-infected women to prevent mother-to-child transmission (MCT). The overall ZDV prophylaxis coverage for the province reached 68% of all HIV+ pregnant women in the fourth quarter of 1997, either through the MOPH program or through the North Thailand Perinatal HIV Prevention Trial (NTPHPT), the parallel clinical trial conducted by the MOPH and the Ministry of Universities. Analysis of the data collected throughout the province show excellent compliance with the intervention (around 90%). This coverage was achieved at an additional cost of $0.13 (US) per capita per year, affordable even in the context of the economic crisis, and represents less than one percent of public health expenditures in Thailand. The cost per Disability Adjusted Life Years (DALY) saved is approximately $35 (US), making it a highly cost-effective intervention.

In less than a year, the MOPH implemented this program on a large scale in this relatively poor province, with limited external support. Women receive pretest counseling at their first prenatal visit, are offered HIV testing and, if they accept, return for posttest counseling two weeks later. In the case of a positive test result, a confirmation test is performed at the provincial hospital. These identified HIV-infected women are offered zidovudine (ZDV), beginning at the 34th week of pregnancy.

Before starting treatment, the women's hemoglobin, CBC and platelets are measured. Infants begin taking oral ZDV shortly after birth and continue until they are one week old.

Subsequently, health centers regularly follow the infants, and volunteers provide case management of childhood illness, nutrition problem solving, childhood immunizations and home visits. Mothers feed the infants breastmilk substitutes, and women with insufficient income receive the substitutes free of charge.

The northern Thailand experience provides important insights regarding the feasibility of large scale interventions to prevent perinatal HIV, such as the need for the reorganization of the delivery of health care. It also shows the necessity of quality counseling to ensure the success of the intervention. On the basis of this experience, a simplified schedule of three key intervention phases (Screen, Treat and Care), which can be incorporated into routine mother and child health care, is proposed.

Follow-up of the child, however, will require more frequent and intensive contact with health care services than usual. In order to facilitate the successful and sustainable operation of this approach in other contexts, this paper delineates the key conditions that will help ensure that the intervention is effective, efficient and financially viable.

It proposes an analytical framework to detect frequent implementation problems and provides examples of likely causes. Many of the problems are common to all three phases.

The health care reforms underway in many countries provide an excellent opportunity to address these issues.