Although last week the National Institute of Allergy and Infectious Diseases (NIAID) gave up on its plan to perform the large scale human experimental testing of an AIDS vaccine, the quest for an efficient HIV vaccine is still ongoing.

Even though things were coming along quite well and the project showed great promise, given its similarity to the previously attempted and failed Merck vaccine, PAVE (the Partnership for AIDS Vaccine Evaluation) was temporarily shut down until further research is completed.

The PAVE was supposed to be given to 8,500 volunteers in the US, South America, Eastern and Southern Africa.

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, said he was taking full responsibility for the decision to delay the vaccine’s testing; he then added that it took him several months of debates and discussions to reach this resolution.

The decision does not help one bit with the already much delayed plan to produce a vaccine that works. Back in 1984, government health officials made a promise to come up with an H.I.V. marketed vaccine by 1987.

Several vaccines are currently being developed worldwide; however, the PAVE was the most promising out of a new class of HIV vaccines, approved for human testing.

Dr. Anthony Fauci said it was becoming quite clear that for now, more effort should be put into fundamental research and animal testing. Dr. Alan Bernstein, Global HIV Vaccine Enterprise executive director, said he supported Dr. Fauci’s decision and talked about an "urgent need for a diversity of new approaches to H.I.V. vaccine design."

Scientists consider the development of an H.I.V. vaccine as on the most difficult scientific challenges in history, because of the very nature of the virus. Whether or not all these efforts will materialize remains to be seen.