Animals

Those of you who follow our Facebook page have noted several recent stories on the zoonotic disease front. New human cases were reported of the influenza A (H3N2) variant, a swine virus that thus far appears to cause mild disease and has limited-to-no transmissibility from human-to-human (virtually all cases have been among those with direct pig contact, often at summer fairs). Meanwhile, an avian H3N8 strain was reported to be the cause of a recent fatal outbreak of pneumonia among New England harbor seals—whenever an avian strain demonstrates adaptation to a mammalian host, it is cause for concern. This development further stresses the importance of open and transparent work to understand the key features of virulent influenza strains that predict human infection and transmission (in other words, lift the “voluntary moratorium”). Finally, we have a very provocative report suggesting that rabies virus exposure, at least in remote communities in the Peruvian Amazon, may not always result in infection and death. Rabies is notorious for having a human fatality rate approaching 100%, with very few reports of survival after clinical infection. It is surprising, then, to find evidence for nonlethal rabies virus infection among those with bat exposure and no history of vaccination. Too soon, really, to determine if this finding is explained by unique genetic-immunologic characteristics of this remote population, or if there are other mechanisms of nonlethal exposure that have not yet been identified.

While we are on the topic, I’d like to plug my favorite blog about infections in animals, Worms and Germs, by Drs. Scott Weese and Maureen Anderson of the Ontario Veterinary College's Centre for Public Health and Zoonoses.