1. Introduction
As of the end of 2003, about 40 million people
worldwide were estimated to be living with AIDS,
almost all of them prime-aged adults and 95% of
them living in developing countries [1]. Roughly 3
million people died from AIDS in 2003. Prevention
programs have been launched in virtually every
country—to provide information, raise condom use,
reduce numbers of sexual partners, promote safe sex
and injecting practices, and to reduce mother-to-child
transmission. Nevertheless, more than 15,000 people
become newly infected with HIV every day. Despite
the best efforts of scientists, there is still no cure for
AIDS. The advent of highly active antiretroviral therapy
(HAART) has reduced the mortality rate among
patients in high-income countries, although it remains
costly, suffers from significant implementation
problems (side effects, difficult compliance, and viral
resistance) and cannot eradicate the virus from the
body. A safe, effective and affordable AIDS vaccine
would be a valuable addition to the existing arsenal
of prevention strategies.