New Insights into Animal-Borne Disease Outbreaks

In the wake of the recent Ebola virus epidemic in West Africa, a reevaluation of the ways plague spreads through prairie dog colonies in the western United States has yielded insights that could help explain outbreaks of plague, Ebola, and other diseases that can be transmitted by animals to humans. These include West Nile Virus disease and MERS (Middle East Respiratory Syndrome). The study, led by Dan Salkeld and Mike Antolin of Colorado State University and described in the journal BioScience, suggests that even deadly diseases may persist unnoticed in a population for years as smoldering infections, rather than jump from another species immediately before an outbreak. Moreover, the investigations commonly launched after a human outbreak can yield misleading information about which host species were actually responsible. For instance, it seems that grasshopper mice and coyotes, which scavenge plague-killed black-tailed prairie dogs, may speed transmission of the plague-causing bacterium by acquiring and spreading the flea vectors. Thus, fleas can transmit plague faster than was once thought. According to Salkeld and colleagues, the disease can persist in wider prairie dog populations through repeated dispersal and reinvasion despite local outbreaks that can kill 95%-100% of the members of affected colonies. The authors state that this "slow, smoldering, cryptic disease transmission in animal populations prior to outbreaks in humans is... a hypothetical explanation for th...
Source: BioScience Press Releases - Category: Biology Source Type: news