Showing papers by "Marie-Louise Newell published in 1993"

Estimating the rate of mother-to-child transmission of HIV. Report of a workshop on methodological issues Ghent (Belgium), 17-20 February 1992. The Working Group on Mother-to-Child Transmission of HIV.

Abstract: PURPOSE: In the last 8 years, numerous cohort studies have been conducted to estimate the rate of mother-to-child transmission (MTCT) of HIV. Many of these have faced problems in data collection and analysis, making it difficult to compare transmission rates between studies. This workshop on methodological aspects of the study of MTCT of HIV-1 was held in Ghent (Belgium) in February 1992. STUDY SELECTION AND DATA EXTRACTION: Fourteen teams of investigators participated, representing studies from Central (five) and Eastern Africa (three), Europe (two), Haiti (one) and the United States (three). A critical evaluation of the projects was carried out, under four headings: (1) enrollment and follow-up procedures, (2) diagnostic criteria and case definitions, (3) measurement and comparison of MTCT rates and (4) determinants of transmission. RESULTS OF DATA ANALYSIS: Reported transmission rates ranged from 13 to 32% in industrialized countries and from 25 to 48% in developing countries. However, no direct comparisons could be made because methods of calculation differed from study to study. Based on this review, a common methodology was developed. Agreement was reached on definitions of HIV-related signs/symptoms, paediatric AIDS and HIV-related deaths. A classification system of children born to HIV-1-infected mothers according to their probable HIV infection status during the first 15 months of life, allowed the elaboration of a direct method of computation of the transmission rate and of an indirect method for studies with a comparison group of children born to HIV-seronegative mothers. This standardized approach was subsequently applied to selected data sets. CONCLUSIONS: The methodology can now be applied to all studies with sufficient follow-up and comparisons made between transmission rates. This step is essential for assessing determinants of transmission and for the development of a common approach for the evaluation of interventions aimed at reducing or interrupting MTCT of HIV.

Screening for HIV infection in pregnancy

Abstract: Antenatal HIV screening policies throughout the British Isles were surveyed and results linked to data on HIV-infected pregnant women notified through the Royal College of Obstetricians and Gynaecologists. Units offering HIV testing to all pregnant women were compared with those offering it only to women considered to be at risk, and in both situations fewer than SO% of infected women were identified as HIV infected fm the first time in antenatal clinics. Based on laboratory reports of HIV infection in women of childbearing age, paediatric reports of children born to HIV positive women and unlinked anonymous neonatal screening programmes, there was evidence of under-recognition of HIV infection in pregnancy, particularly in England and Wales.