August 31, 2000
Texas Reports State's First St. Louis Encephalitis Case in Two
Spurs Polk County Warning...
Texas Department of Health (TDH) officials are
advising Polk County residents and visitors to take extra precautions to avoid mosquito
bites after a local man was diagnosed with St. Louis encephalitis earlier this month.
The illness is caused by a virus transmitted by
"We're not trying to create undue alarm, but
we want people to know there is at least one infected mosquito out there and to pay
special attention to reducing their exposure to mosquitoes," said Dr. Paul McGaha,
director of TDH's regional office in Tyler.
Polk County has a population of about 40,000, but
local officials say thousands of others visit Lake Livingston, a popular fishing and
recreation lake in the county, each week-end. McGaha said health officials are not
recommending that people cancel their visits. "But we do want them to be aware of the
situation and to take extra precautions," he said.
Though other species of mosquitoes can carry the
virus, health officials say the primary carrier of the St. Louis encephalitis (SLE) virus
is Culex quinquefasciatus, a common mosquito in East Texas. The Culex mosquitoes hatch in
stagnant water that has higher levels of organic matter. Mosquitoes become infected
when they feed on infected wild birds which serve as a reservoir for the virus.
Health officials encourage reducing mosquito
hatching grounds by removing or emptying sources of standing water. McGaha said people
should use a mosquito repellant when outdoors and should try to avoid being outdoors
around dawn and dusk when the Culex mosquitoes are most active.
Spraying efforts to kill mosquitoes are underway.
TDH is trapping mosquitoes to test for the presence of the virus and is alerting area
physicians and hospitals.
SLE attacks the membranes that cover the brain and
spinal cord. Early symptoms include headache and a stiff neck. SLE illness can be mild,
but it also can cause brain damage, paralysis and death. The young and the elderly are
more likely to suffer more severe complications.
The Polk County man is the first SLE case reported
in Texas since 1998 when four cases were recorded. The last SLE outbreak in Texas was in
1995 when 22 cases, including 19 in Dallas County, were reported. The last death from SLE
in Texas occurred in 1995.
(For more information contact Paul McGaha, D.O.,
TDH Regional Director, Tyler, at 903-533-5264; or Doug McBride, TDH Public Information
Officer, Austin, at 512-458-7524.)