BBC NEWS Americas Africa Europe Middle East South Asia Asia Pacific
BBCi NEWS   SPORT   WEATHER   WORLD SERVICE   A-Z INDEX     

BBC News World Edition
 You are in: Health  
News Front Page
Africa
Americas
Asia-Pacific
Europe
Middle East
South Asia
UK
Business
Entertainment
Science/Nature
Technology
Health
Medical notes
-------------
Talking Point
-------------
Country Profiles
In Depth
-------------
Programmes
-------------
BBC Sport
BBC Weather
SERVICES
-------------
EDITIONS
Aids 'dates from 1930s'
Romanian Aids baby
Aids has hit generations around the world from Romania...
An international group of scientists has said evidence suggests Aids first appeared 70 years ago - and not in the 1950s as previously thought.

US and UK scientists used a supercomputer to analyse genes of the human immunodeficiency virus, HIV, which leads to Aids.

In a paper in the journal Science, they explain that they used rates of genetic mutation to work out that the virus probably appeared in 1931.
Cambodia Aids baby
... to Cambodia...

This early date is even more remarkable, given that HIV was not even recognised less than 20 years ago.

Researchers speculate that it may have been transmitted from apes to humans near the turn of the century and remained isolated in a small population until the 1930s.

Alternatively the virus might have jumped over to humans in about 1930 and started spreading immediately, or a decade or two later.

Constant rate

Research to determine the virus's ancestry was based on a "molecular clock" analysis of variations of certain HIV genes.
Ugandan Aids baby
... to Uganda: Some African countries could see a 20% drop in their workforces due to Aids

Since genes mutate at a constant rate over time, it was possible to work back using this information and estimate when the main group of strains split off from a common origin.

Researchers led by Bette Korba, from Los Alamos National Laboratory, New Mexico, said this probably happened between 1915 and 1941 and gave 1931 as the most likely year.

Contradiction

One common theory holds that HIV emerged through polio vaccination programmes in Central Africa between 1957 and 1960.

It was thought that polio vaccines may have been grown in kidney cell cultures derived from chimpanzees kept at a research facility near Stanleyville, now Kisangani in the Democratic Republic of Congo.

But the new theory would appear to contradict that.

"Our analyses suggest that the HIV-1 M [main] group ancestral sequence occurred decades before the vaccination programmes and that the diverse subtypes were well established by 1957," said the researchers.

Aids was not identified as a clinical condition until 1981, but retrospective studies have revealed cases dating back to the 1970s.

New figures from the International Labour Organisation suggest that the Aids pandemic is so serious throughout Africa that in the next two decades it will lead to a 20% drop in the workforce of some countries.

 WATCH/LISTEN
 ON THIS STORY
Helen Sewell of BBC Science
"Scientists used a supercomputer to analyse the HIV genes"
See also:

10 May 00 | Health
26 May 00 | Health
11 May 00 | Health
06 May 00 | Africa
Internet links:


The BBC is not responsible for the content of external internet sites

Links to more Health stories are at the foot of the page.


E-mail this story to a friend

Links to more Health stories

© BBC ^^ Back to top

News Front Page | Africa | Americas | Asia-Pacific | Europe | Middle East |
South Asia | UK | Business | Entertainment | Science/Nature |
Technology | Health | Talking Point | Country Profiles | In Depth |
Programmes