By Jayson Jacoby
Three Richland-area residents were likely infected with West Nile virus through mosquito bites earlier this summer, according to the Oregon Health Authority and the Baker County Health Department.
The agencies are calling the three cases, the first human West Nile infections in Baker County since 2007, "presumptive" because final test results are still pending.
But Dr. Emilio DeBess, public health veterinarian with the Oregon Health Authority (OHA), said the three Baker County residents definitely contracted either West Nile virus or St. Louis encephalitis.
Both are spread by mosquitoes, but the tests that have been done so far on blood samples from the three people could not distinguish between the two diseases, DeBess said.
The federal Centers for Disease Control and Prevention in Atlanta can perform that test, but results probably won't be available for two to three weeks, he said.
It's far more likely that the three Baker County residents were infected with West Nile virus, DeBess said.
St. Louis encephalitis is exceedingly rare, with only one confirmed case in Oregon between 2003 and 2012.
By contrast there have been 153 confirmed cases of West Nile virus in Oregon residents during that period.
Martha "Marty" Pennock, 70, of New Bridge, about three miles north of Richland, is one of the three Baker County residents infected with a mosquito-borne illness.
Pennock said she spent about a day and a half at St. Alphonsus Medical Center-Baker City on Aug. 5-6, suffering from dehydration and kidney problems related to the infection.
Pennock said Thursday that she feels better than she did in early August but that she hasn't fully recovered from the weakness and lethargy that are among the virus' common symptoms.