Researchers have discovered six people living in remote areas of Peru (Truenococha and Santa Marta) with natural antibodies against rabies despite never having received a vaccination for this deadly virus. They hypothesize that vampire bats actually transmitted small doses of the virus to people over time creating the natural antibodies. All six individuals reported having been exposed to the bats either through a bite or direct contact (scratch, touching).
While the levels of antibodies in the individuals were low, they might be enough to trigger an immune response against the rabies virus if exposed. Since this was such a small sample of people with natural immunity against the virus, more studies are needed to verify if repeated exposure to the bats (and hence small doses of the virus) really would be sufficient to build up natural antibodies to thwart an infection.
Gilbert AT, Petersen BW, Recuenco S, Niezgoda M, Gomez J, Laguna-Torres VA, and Rupprecht C. Evidence of rabies virus exposure among humans in the Peruvian Amazon. The American Journal of Tropical Hygiene and Medicine. 87(2): 206-215, 2012.
Follow Dr. Dolittle on Twitter: @DrDoScienceBlog
there was a time when vets didnt get vaccinated against rabies, and still never got rabies even after getting bitten or scratched by street dogs... turned out that they had a nice titre of anti rabies antibodies... :D somehow, the west always overlooked our data :) ....
The fact that some antibody reacts with rabies antigens is by no means proof of contact with the antigen. The reasong is antibodies are promiscuous in general (heterophile) and tend to cross react with other antigens (similar epitopes).
Assuming protection, as these "scientists" do, is just wishful thinking. These guys are interpreting their observations in an interested manner. They're seeking to sell a product, so they purposedly ignore the factors I mentioned above.
"..there was a time when vets didnt get vaccinated against rabies, and still never got rabies even after getting bitten or scratched by street dogs..."
Before antigen tests were available (in the 60s) rabies and "idiopathic" encephalopaties were clinically indistinguishable.
The reason why some encephalopathies were called "rabies" if an animal had bitten the victim up to one year before, seems to be rooted in superstition (looking for culprits) rather than evidence of actual transmission of a causative agent.
Today "idiopathic" encephalopaties are happening, but the lower (apparent) incidence of "rabies" is due to serological "confirmation" that act as a filter on a set of clinical cases that would have been called "rabies" before.
vets, scratched by street dogs, didnt get rabies, have natural antibodies against rabies, never showed any clinical symptoms of rabies.... if you associate all these, then i think there is little not to believe active immunity against rabies can be achieved artificially... by the way, i never said that its a definite proof, but what i meant is that further trials can be undertaken as rabies is a major public health concern in some countries...
Fear viggy, what needs to be seriously researched is whetehr the so-called "rabies virus" is an infectious entity according to Koch's postulates. As far as I know it has never been proven to fulfill any of them, let alone proven to cause encephalitis. This is a very bad bad thing!
it is almost universally known fact that koch's postulates do not hold true for viruses... we cannot show presence of viruses in every case of a suspected viral disease hence we use antibodies for that, (and sometimes just clinical symptoms)... and i think we all will agree that rabies vaccine has been proven to be efficacious.... the last arguement is not directly linked to the discussion whether natural immunity is possible in rabies (disease) or not... ofcourse you cannot test those people by getting them bitten by a rabid animal...
"...it is almost universally known fact that koch’s postulates do not hold true for viruses…"
That's a strong indicia of viruses beign the wrong cause of a disease.
There's no better criteria for causation than Koch's, only workarounds to push a wrong cause - and make mone treating it.
"… and i think we all will agree that rabies vaccine has been proven to be efficacious…"
No we don't. Before serologies were availeable in the 60s "rabies" encompassed encephalytes of various causes, since the diagnostic criteria were purely clinical.
With the advent serology a case of "rabies" was subject to a stricter redefinition, but still keeping the name. What before the 50s would have been classified as "rabies" now it's not, therefore the apparent reduction in incidence is spurious and a definition artifact.
It is always interesting to hear of the unique immunities that some people develop.