High prevalence of HIV infection among youth in a South African mining town
is associated with HSV-2 seropositivity and sexual behaviour

 NATAP - www.natap.org
-----------------------------------

Bertran Auvert, Ron Ballard, Catherine Campbell, Michel Caraël, Matthieu
Carton, Glenda Fehler, Eleanor Gouws, Catherine MacPhail, Dirk Taljaard,
Johannes Van Dam, Brian Williams

AIDS Volume 15, number 7, p.

In this study published in AIDS, the authors found an extremely high
prevalence of HIV among young women (34%) and men (9%) aged 14-24 years from
a township in the Carletonville district of South Africa. HIV prevalence
among women aged 24 was 66%, one of the highest rates ever reported in a
general population. The authors suggest that these remarkable findings are
due to high rates of HIV transmission from men to women, and the major role
played by HSV-2 (herpes simplex virus type 2) in the spread of HIV in this
population.

South Africa is experiencing one of the most rapidly growing HIV epidemics in
the world. In 1990 the prevalence of HIV infection among women attending
antenatal clinics was less than 1%. By the end of 1999 national prevalence
had reached 23%. Most of the studies that have been performed in sub-Saharan
Africa to date have investigated risk factors for HIV infection among adults,
but young people, and especially young women, are at particularly high risk
of HIV infection in many developing countries.

The authors claim that the high prevalence of HIV infection among young women
compared to young men in the Carletonville study is not simply due to either
very high rates of infection amongst their partners or to very high levels of
sexual activity. In fact, in almost all surveys carried out across Eastern
and Southern Africa by the World Health Organization, men report a higher
turnover of partners before marriage thanwomen, and in this study the mean
number of partners was 4.7 for men and 2.6 for women.

One reason for this discrepancy in HIV prevalence between young men and young
women is that HIV is more easily transmitted from men to women than from
women to men. Studies in industrialized countries have shown that, in the
absence of other risk factors, men are two to three times more likely to
transmit HIV to women than vice versa. However, the estimates of
transmissibility of HIV from men to women in the Carletonville study are
significantly higher than this, even taking into account the possibility of
women under-reporting their number of sexual partners. There are several
possible explanations for this. A recent study has shown that viral load is
an important predictor in the risk of heterosexual HIV transmission, and
viral loads are likely to be higher in South Africa than in Europe or the US
due to the reduced availability of effective drugs and treatment. Another factor may be the high prevalence of HSV-2 (herpes simplex virus type 2) in this population, as HSV-2 can
facilitate HIV infection.

In the Carletonville study HSV-2 status was the most significant factor
associated with HIV status for both men and women. For example, men infected
with HSV-2 were seven times more likely to also be HIV positive than those
who did not have HSV-2. HSV-2 acts as a co-factor in HIV transmission by
causing genital ulcers which both increase the susceptibility of the
uninfected to infection by HIV, and increase the infectivity of those who
already carry the virus.

Reducing HIV transmission in this population is a major challenge. At the
present time genital herpes can only be treated at considerable cost, and no
vaccine is currently available. Therefore the best options for reducing
transmission include communication campaigns aimed at alerting the population
to the relatively mild manifestation of genital herpes and the need to
abstain from sexual contact while lesions persist. In addition it is
important to find ways to persuade young people to reduce their number of
sexual partners and, most importantly of all, to substantially increase
condom use; in this study, 41% of men and 42.5% of women reported never
having used condoms. As most young people in this study were still at school
when they had their first sexual experience, attempts to limit the future
spread of HIV should involve not only prevention in the community but also
effective school-based interventions as an essential part of the school
curriculum.

If you would like to be removed from Email list please reply with your Email
address and unsubscribe in the Subject.