West Nile fever has swept across our continent in record time, carried by mosquitos passing the virus from bird to bird and bird to human. We in the northern Chihuahuan Desert are right with the rest of the country on this, with both human and avian cases locally. However, in Europe, West Nile fever has long been endemic, with nothing at all like the dire effects we've had in North America. What's the difference?
There are two major opinions in the scientific world. One, that the
newly arrived virus found only non-resistant birds and humans. As with the smallpox
that decimated Native American populations, it spread rapidly with disastrous results.
There is, though, another possibility. In a study in the Old World of members of the
mosquito group that carries the virus, the strains that feed on birds appear separate
from those that feed on humans. In the New World apparently these strains have
hybridized, leading to the suspicion that a mosquito may feed on a bird and then on a
person—the perfect carrier.
Listen to the Audio (mp3 format) as recorded by KTEP, Public Radio for the Southwest.
Contributor: Arthur H. Harris, Laboratory for Environmental Biology, Centennial Museum, University of Texas at El Paso.
Desert Diary is a joint production of the Centennial Museum and KTEP National Public Radio at the University of Texas at El Paso.