Business Day (South Africa) (10.21.03) - Thursday, October 23,
Two of South Africa's leading HIV/AIDS academics have reacted
with skepticism to a study by former health department
Director-General Olive Shishana. The study said the epidemic
peaked last year with about 4.69 million infected people and
has started to level off. It also said the HIV incidence rate
among 15- to 49-year-olds had decreased from 4.2 percent in
1997 to 1.7 percent in 2003.
"We were surprised by these findings, but when you look
closely it coincides with the introduction of major
interventions like condom distribution," said Shishana,
executive director of an HIV/AIDS research program at the
Human Sciences Research Council. The new study used data from
the health department's HIV prevalence surveys of pregnant
women from 1990-2001, and from the Nelson Mandela-HSRC
HIV/AIDS household survey published last year. The Mandela-
HSRC study contradicted previous research by showing HIV
prevalence rates were highest in Free State and Guateng, not
KwaZulu-Natal and Mpumalanga.
"The Mandela-HSRC study has not been through a peer-review
process," said University of Natal epidemiologist professor
Quarraisha Abdool Karim. "There are a number of flaws in the
study, and in the interpretation and data analysis that have
not been addressed... the use of these data to calibrate a new
model questions the validity of the model."
Professor Rob Dorrington, head of Cape Town University's
center for actuarial research, questioned whether the model
showed anything more than the researchers' assumptions about
future prevalence rates. "The authors assumed the epidemic
peaked in 2002 and than that prevalence levels declined. All
their 'results' are thus contingent on these heroic
assumptions," he said.
The researchers have refused to let other academics examine
their data or questionnaires. The study, "Epidemiological and
Demographic HIV/AIDS Projections: South Africa," appeared in
the African Journal of AIDS Research (2003;2(1):1-8).