New Virus Kills Three in California
WebMD News Archive
Aug. 4, 2000 -- Three California residents have died of infection with a
rare new type of virus carried by rats. Known as the Whitewater Arroyo virus,
it is similar to deadly viruses found in South America. The California cases
are the first to occur naturally in the U.S.
The new virus was first reported in 1996 among the type of pack rats known
as white-throated wood rats. Laboratory studies suggest it is the cause of the
mysterious deaths of a 52-year-old Riverside County woman in June 1999; a
14-year-old Alameda County girl in April 2000; and a 30-year-old Orange County
woman in June 2000. All were hospitalized with fever and difficulty breathing.
Two of the patients had severe liver disease and bleeding.
"We don't want the public to be alarmed; we think this is very
rare," Lea Brooks, spokesperson for the California Department of Health
Services in Sacramento, tells WebMD. "These are very severe and unusual
illnesses. We have a lot of focus on prevention."
The California cases do not appear to represent an outbreak. The deaths,
which took place over a 14-month period in two widely separated regions, appear
to be completely unconnected. In the wake of the deaths, California public
health authorities are stepping up surveillance efforts and warning residents
to avoid contact with rats and other rodents and their droppings.
Like the hantavirus -- another rare but dangerous virus, carried by deer
mice -- people get infected by breathing dust contaminated with the urine,
feces, or saliva of infected rodents. Human-to-human transmission can occur
through contact with blood or other excretions containing virus particles, but
this rarely happens outside health care settings and can be prevented by the
use of normal hospital gowns and gloves.
T.G. Ksiazek, PhD, DVM, is acting chief of the special pathogen branch of
the CDC's disease assessment section. He says that while all three known cases
were fatal, it is too soon to know exactly how deadly the new virus will turn
out to be. "Whenever something new pops up, the first cases you find are
the most serious," he says.
Public health officials are urging people to take these simple but effective
- Do not touch or feed wild rodents or any other wild animals.
- Properly dispose of trash and clutter. Move woodpiles away from
- Prevent rodents from entering residences by blocking holes. Control rodents
with spring-loaded (snap) traps.
- Store food and garbage in rodent-proof containers. Pet food should not be
- Avoid creating dust when cleaning buildings with signs of rodents. Wet the
area thoroughly with bleach and use gloves to clean up. Contact local health
officials for recommendations about safely cleaning rodent-infested areas.
- Cabins and buildings that haven't been lived in for some time should be
aired out. If possible, do not use buildings with signs of rodents until they
have been cleaned properly.
- When sleeping outdoors, avoid campsites near rodent droppings, burrows, or