Not only are women biologically more prone to HIV infection than men, but for a variety of social, cultural and economic reasons they also have a harder time coping with the illness once infected, particularly in Africa.

"Nearly 60 percent of infections at the moment are in women, most of them in younger women," explained Helen Jackson, HIV/AIDS advisor for southern Africa with the UN Population Fund.

"The physiological data seem to indicate it's something like twice as easy for women to become infected as for men," she said at the 14th International Conference on AIDS and Sexually Transmitted Infections in Africa (ICASA) being held this week in Abuja.

African women are particularly hard hit. Of women affected worldwide, 77 percent are Africans, according to Michel Sidibe, deputy director of UNAIDS, the body that brings together ten UN agencies in the fight against HIV/AIDS.

In southern Africa, young women aged between 15 and 24 are at least three times more likely to be HIV-positive than men of the same age.

Physiologically, it is the make-up of their genital area that makes women more vulnerable, but socio-cultural factors also play a large role.

"Infection often occurs between older men and young women. There is a greater chance of the women's partners being HIV-positive (than if they had sex with boys of their own age) and the immature vaginal tract is more easily infected," Jackson explained.

Women who are financially dependent on their male partner find it difficult to negotiate the use of condoms or to refuse unprotected sex even if they suspect the partner is infected or sick.

A UNAIDS study published earlier this month illustrates the extent to which women are vulnerable even if they stick to one partner in a lifetime.

"Among women surveyed in Harare (Zimbabwe), Durban and Soweto (South Africa), 66 percent reported having one lifetime partner, 79 percent had abstained from sex at least until the age of 17. Yet 40 percent of the young women were HIV-positive," the report said.

Some women engage in commercial sex, either as a means to survive or for the better off as a way of acquiring coveted new clothes or a smarter mobile phone.

Once infected, women's access to testing, counselling and care is in many cases dictated by the male partner, particularly in rural societies.

"In many societies women carry an incredible workload", Jackson said, citing child rearing, fetching water and either agricultural work or small-scale trading.

"If the husband has been earning a wage and becomes sick then they carry an even greater responsibility", she added, emphasizing that most of the responsibility for caring for other AIDS sufferers in the family traditionally falls on women.

"The chances of infection are greater in women; they are the ones who can transmit the virus to their children and on top of all that they tend to get blamed for catching it," Jackson resumed.

There are, however, signs the situation could be slowly changing.

UNAIDS chief Peter Piot, in a keynote address to the conference emphasized the need to tackle the "structural drivers" of the epidemic.

He cited "sexual violence against women" and "inheritance and property rights for women".

"There is increasing local, national and international recognition of the burden of women. Discussion is now going on about gender amid groups that would not previously have broached the subject and women are also demonstrating being assertive," Jackson noted.