The failure of 'classical' vaccines to induce protection to the most important of all retroviruses, HIV, has led to the development of a huge variety of 'molecular vaccines', i.e. vaccines produced using modern molecular biological techniques. Such vaccines range from simple plasmid DNA coding for the genes of choice, through recombinant viruses carrying such genes to engineered bacteria designed to deliver HIV genes to the mucosal immune system.

Evaluation of AIDS vaccines has resulted in sporadic successes and many failures and the few human clinical trials have been, at best, negative. However, the relative success of molecular vaccines in combating other retroviral infections and the continuing refinement of HIV/SIV vaccines showing some efficacy suggests that a molecular AIDS vaccine may be achievable. In the end, the HIV/AIDS pandemic will only be defeated by the development of an effective, stable, and inexpensive vaccine.

Further reading:
Retroviruses: Molecular Biology, Genomics and Pathogenesis
AIDS Vaccine Development: Challenges and Opportunities

Labels: AIDS pandemic, AIDS Vaccine Development, HIV vaccines, SIV vaccines