One of the big topics of the National AIDS Conference in Toronto this week was on vaccines versus microbicides. Researchers have yet to find a safe and effective HIV vaccine due to the viruses shifty nature. Many researchers have started veering away from the vaccine idea to gels or creams that prevent the transmission of HIV during sex. Microbicides work in many different ways to prevent infection with sexually transmitted diseases (STDs). Some work by maintaining an acidic pH in the vagina which enhances the natural vaginal defense mechanism. Another class of microbicides can prevent virus replication once it has entered cells. Some microbicides act by simply forming a protective barrier. Microbicides can be in a gel or cream form and even as suppositories. Some even have spermicidal activity.

The main talk at the conference this year has been all about prevention. The London School of Hygiene and Tropical Medicine did a simulation and found that a microbicide that is only 60% effective could prevent 2.5 million infections over three years. 2.5 MILLION. That's a big number particularly when you consider that at the end of 2005 17.3 million women were living with HIV.

So is a vaccine really all that important? Of course, but I don't think we should be putting all our eggs in one basket. We may not be able to cure AIDS, but its high time we find an effective way of preventing it.