Smallpox has been eradicated from the face of the Earth following a highly effective, worldwide vaccination campaign. Paralytic poliomyelitis is no longer a problem in the U.S. For some reason the spread and use of effective vaccines against the poliovirus.
HIV vaccine development efforts have come up short
In the early 1980s when the new virus AIDS burst onto the scene and the virus that caused it was discovered in 1983-84, all that was is only natural to think that the research alliance would be able to develop a vaccine for it. Vaccines have surely been society’s most dominant weapon against viral diseases of medical importance.
In 1984 famous press conference announcing HIV as the cause of AIDS, then U.S. Secretary of Health and Human Services Margaret Heckler predicted that a vaccine would be available in two years. Although it is now 37 years has been pass and there is no vaccine. In stark contrast speed of COVID-19 vaccine growth and division puts the lack of an HIV vaccine. There is no such hand of Government the main issue is with lack of spending.
Having said that there have been five large-scale Phase 3 vaccine efficacy trials against HIV, each at a cost of over US$100 million. The first three of these failed quite convincingly; no protection against possession of HIV infection, maintaining of viral loads in those who did become infected. There was a statistically significant higher frequency of infection in individuals who had been treated. The challenge lies in HIV itself. This includes the remarkable HIV strain unlikeness and the resistant avoidance strategies of the virus.
The complexity of HIV
Is this the problem that the basic biological properties that HIV has developed and make the development of a successful vaccine very, very difficult? What are those properties?
Everyone knows that people need to get re-vaccinated against the disease virus each season because time-to-time changes in the disease may cause a major problem. HIV has evolved an ability to produce and empower many modifications in its genetic data.
The outgrowth of this is an enormous amount of variation among strains of the virus not only from one individual to another but even within a single individual. Well, the variability of HIV within a single infected individual exceeds the entire worldwide sequence variability in the influenza virus during an entire season.