How Do We Interpret the HIV Incidence Estimates Reported by Kumwenda et al?

Abstract

Kumwenda et al have reported on HIV incidence estimates from a multisite study conducted in Lilongwe and Blantyre (Malawi) and Harare (Zimbabwe). Several issues deserve comment: 1) the HIV incidence estimates 2) the reasons behind high incidence of HIV despite a declining sexually transmitted infection (STI) prevalence 3) laboratory diagnosis of HIV in the study and 4) interpretation of the findings. The authors report of HIV incidence rates of 4.9 and 4.3 per 100 woman-years and compare these with previous estimates as reported by Taha et al (Malawi) and Mbizvo et al (Zimbabwe) and argue that HIV incidence has not changed in these communities. The problem with this comparison is that the current study had a different population group from the earlier studies. Although family planning and postnatal clinic attendees were recruited by Kumwenda et al the previous studies used antenatal and postnatal a population that may not be comparable when other family planning attendees (nonpostnatal) are used. Also in the current study the women recruited received 5 intensive counseling and condom promotion session thus making them less representative of regular clinic attendees or even the general population. If the populations used previously are different from the current study it may be misleading to draw conclusions of a trend for populations that may not comparable. (excerpt)