Eradication Of Smallpox Linked To HIV Infection Spread

Eradication Of Smallpox Linked To HIV Infection SpreadScientists believe eradication of smallpox worldwide may have inadvertently led to the spread HIV infection.

They believe the smallpox vaccine which is no longer in use, also offered some protection against the AIDS virus, the absence of which has helped HIV to flourish. Trials by US investigators have indicated how the smallpox vaccination interferes with how well HIV multiplies.

However, they say in the journal BMC Immunology it is far too early to recommend smallpox vaccine for fighting HIV.

Dr. Raymond Weinstein, lead researcher from George Mason University in Virginia said, wars, re-use of unsterilised needles and the contamination of early batches of polio vaccine, are several explanations put forward for the rapid spread of HIV in Africa. However, they have all been either disproved or do not offer a plausible explanation for the behaviour of the HIV pandemic.

Weinstein and his colleagues believe smallpox immunisation, which was gradually withdrawn from the 1950s to the 1970s, following the worldwide eradication of the disease, somewhat explains the recent rises in HIV prevalence.

To discover a link between the two events, researchers studied the white blood cells taken from people recently immunised against smallpox and tested how they responded to HIV.

They found significantly lower replication rates of HIV in blood cells from vaccinated individuals, compared with those who were not vaccinated against small pox. The smallpox vaccine seemed to reduce HIV replication five-fold.

Researchers believe the vaccination offers some protection against HIV by producing long-term alterations in the immune system.

Jason Warriner, Clinical Director for the Terrence Higgins Trust said, the withdrawal of the smallpox vaccine contributing to the initial explosion of HIV cases worldwide, is a plausible explanation. Though, further studies are necessary into the role receptor cells play, and till a way is found to eradicate the virus from the body, the focus should remain on stopping it from being passed on in the first place.