9
$\begingroup$

So, the HIV-1 jump to humans occurred as early as the 1920s, but the AIDS epidemic didn't start until the early 1980s.

Some things I don't understand about this:

  • Why the delay?
  • What is needed for a successful zoonosis transmission in the first place?
  • If Bushmeat practices (eating meat from non-domesticated animals, in this case HIV-infected fruit bats) have been the same for centuries, why has HIV only really spread in THIS century?
$\endgroup$
  • 1
    $\begingroup$ There is probably a decent answer, and aandreev may have touched on some the reasons, but I don't have time to write one right now. I have heard about blood samples taken in the Congo in like 1914 that tested positive for HIV. The advent of european colonialism, easier travel with trains, etc probably allowed HIV to get from remote villages to larger cities. Also, the virus probably had to mutate to grow in humans instead of only chimpanzees. So it probably took both the mutant virus getting into a human at the same time as travel became easy. $\endgroup$ – user137 Apr 8 '15 at 2:20
  • 1
    $\begingroup$ As usual, Wikipedia has a long article on this topic. Did you read it? $\endgroup$ – Martin Schröder Apr 10 '15 at 22:31
2
$\begingroup$

if Bushmeat practices (eating meat from non-domesticated animals, in this case HIV-infected fruit bats) have been the same for centuries, why has HIV only really spread in THIS century?

We can't really rule out the existence of similar epidemics in the more distant past. In fact, almost certainly they were transmission events from bushmeat (not necessarily of the same virus). The thing that made 20th century different, as the other commenter rightly says, is the mobility. Previously, such transmissions would have lead to local epidemics which would have run their course - leaving super-controllers or individuals with immunity and killing everyone else. And since most of the African cultures haven't left a written record we wouldn't know about such isolated local epidemics. Not to mention that in the unlikely event of such records existing they would hardly be scientific - the disease would be most likely attributed to "evil spirits" or some other supernatural cause.

So, it is really the mobility, the public policies (mass vaccinations by colonial authorities that used the same syringes repeatedly) and the fact that we can retain information in a much better way which make the HIV epidemic different than the ones that almost certainly have happened in the more distant past.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.