Published Date: 2012-08-27 16:58:17
Subject: PRO/AH/EDR> Plague, animal - USA: (CA) squirrel
Archive Number: 20120827.1266637
PLAGUE, ANIMAL - USA: (CALIFORNIA) SQUIRREL
A ProMED-mail post
ProMED-mail is a program of the
International Society for Infectious Diseases
Date: Wed 22 Aug 2012
Source: NBC San Diego [edited]
Three ground squirrels trapped near Palomar Mountain in San Diego's North County tested positive for plague, county officials said Wednesday [22 Aug 2012].
The squirrels likely were not exposed to the bacterial disease any time recently, but the existence still poses a risk to campers and hikers in the area, according to the San Diego County Department of Environmental Health.
The squirrels were trapped at the Cedar Grove Campground and the Doane Campground.
In May , another squirrel trapped at the Cedar Grove Campground also tested positive for plague. A Vector Control spokesperson said it was caught during a separate trapping, and it is not known whether the same squirrel was trapped this time around.
Plague is typically found in rodents and infects humans through the bite of an infected flea. The department has not received any reported cases in humans.
It is typical for animals to test positive for plague, especially during the summer, said the department's director Jack Miller. Still, park officials have set up signs in rural camping and hiking areas, and visitors should take precautions while in the area.
"Set up your tents away from squirrel burrows; do not feed the squirrels, and warn your children not to play with squirrels," Miller said. Miller also said to avoid resting or camping near animal burrows in the ground and to keep pets on a leash or leave pets at home.
Symptoms of plague include swollen lymph nodes, chills and a sudden onset of fever.
ProMED-mail from HealthMap alerts
[Plague is primarily a disease of wild rodents. It is caused by the bacterium _Yersinia pestis_, which is mainly spread by the bites of infectious fleas. The bacterium is not native to North America. When it was introduced, it became established in some rodent populations. Some species were particularly susceptible. For example, _Y. pestis_ caused the extinction of entire colonies of black-tailed prairie dogs. Small rodents such as deer mice and grasshopper mice are suggested to act as the reservoirs. Larger species like squirrels are considered to be more vulnerable to infection.
From the text, it can be inferred that they found antibodies against _Y. pestis_ in these squirrels, which indicates that the pathogen may be circulating in those populations.
A ProMED HealthMap of the affected area can be accessed at http://healthmap.org/r/3bnl. - Mod.PMB]