HIV/AIDS vaccine: An update

Abstract

The global HIV/AIDS epidemic continues to take its toll of human lives. In 2007 there were 33 million people living with HIV/AIDS, with 2.7 million new HIV infections and two million HIV-related deaths.(1) With a total of 2.5 million people living with HIV/AIDS, India too is in the grip of the HIV/AIDS epidemic.(2) According to the HIV Sentinel Surveillance data 2004–2006, there are 156 Category A districts (where there is more than one per cent antenatal prevalence at any given time, in any of the sites, in the last three years).(3) Despite the recent progress in increasing access to treatment and prevention programs, the epidemic continues to outpace the global prevention efforts. In countries that are most heavily affected, the epidemic has led to a significant increase in household poverty and reduction in the life expectancy by more than 20 years.(4,5) The effects of gender inequality leave women and girls more at risk of exposure to HIV. In India, women are becoming increasingly vulnerable to HIV/AIDS and account for around one million cases.(6) Moreover, they have fewer and rather unfeasible options available to protect themselves such as abstinence and use of condom. The best hope of ending the epidemic lies in the development of a suitable vaccine.(7) Vaccines are one of the most effective public health interventions ever known. An HIV vaccine could either prevent disease onset or progression to AIDS. According to mathematical estimates by the International AIDS Vaccine Initiative (IAVI) - provided that other programs for treatment and prevention have been scaled up — an HIV vaccine with an efficacy as low as 30% and coverage as low as 20% could avert as many as 5.5 million new infections between the years 2015 and 2030.(8) The development of an effective vaccine has posed a wide range of challenges, as HIV has proven to be a uniquely complex virus.