Studies in Thailand of the Vertical Transmission of HIV

This letter notes that several international institutions are collaborating on an observational study of maternal-infant transmission of HIV conducted in Thailands Lampang Hospital. The purpose of the study is to correlate viral and immunologic data from mucosal and systemic specimens with transmission data. The study is not a placebo-controlled study and it seeks vital information for understanding vertical transmission of HIV subtype E. At the time the study was initiated the use of zidovudine for reducing vertical transmission was not the standard of care nor was zidovudine available through the Thai Ministry of Health. Thus availability of the drug solely through the research study would have created an unethical inducement for participation. On the other hand provision of powdered milk is an established standard of care and all participants are provided adequate milk. From the time that the Ministry of Health began to assess the effect of zidovudine on vertical transmission of HIV type 1 all subjects in the observational study who met the eligibility criteria for treatment also received zidovudine.