Natural resistance to HIV:- Baby girls are more likely to acquire HIV from their mothers during pregnancy or childbirth than infant boys, who are conversely more likely to achieve cure or remission, researchers say in a new study that sheds light on the gender differences in immune systems.

An estimated 1.3 million women and girls living with HIV become pregnant each year and the rate of transmission to the child during pregnancy, labour, delivery or breastfeeding – in the absence of any intervention – ranges from 15 to 45 per cent, according to the World Health Organization.

Lead researcher Philip Goulder says the study identified some of the key mechanisms by which sustained HIV remission can be achieved – mechanisms that are relevant to children and adults alike.

Goulder and colleagues evaluated 284 infants in KwaZulu-Natal, South Africa, one of the world's highest HIV-prevalent areas, who were started at birth on a mix of HIV medicines known as combination anti-retroviral therapy (cART), after being exposed to HIV during pregnancy.

“We found that HIV transmission to male foetuses was 50 per cent less common than to females,” says Goulder, a professor of immunology at the University of Oxford’s Department of Paediatrics.
“Affected males had lower levels of the virus in the blood and to date, in this study, four male infants have been identified who have achieved HIV cure/remission – ie maintained undetectable levels of HIV in the blood even without therapy,” he told SciDev.Net.

HIV cure is categorised as “true cure” in which the virus has been eradicated totally from the body and “functional cure” or “cure/remission”, in which the virus is no longer detectable in the blood even after treatment has been discontinued. AlphaGalileo/SP