BEDFORD –– Dallas County Health and Human Services Director Zach Thompson is expressing concern that new state standards for human diagnosis of the West Nile virus is why the county's occurence rate is so low this summer.
Every pint of donated blood is screened for West Nile virus.
At Carter BloodCare, so far, none have tested positive this year. But if one does, it will be thrown away.
"If we found a positive unit," explained Dr. Laurie Sutor, a pathologist at Carter BloodCare, "it would indicate that the donor had been exposed to the West Nile virus and we would not want to transfuse that unit."
That standard hasn't changed since 2003. But this year, the state's standards changed, becoming more strict when it comes to diagnosis.
Dr. Charles Tandy was in the hospital for nearly two weeks in May. His blood tested positive for West Nile virus. But, blood wasn't enough.
His case wasn't counted, in part, because he didn't have a fever.
"There have been several other instances where we say we think that's a human case, but it's not," said Thompson.
He was not sure why the state has chosen to raise the reporting standards.
"We're perplexed as well," Thompson said. "We think that this is going to be confusing, not only for public health departments throughout the state, but also for our citizens."
Thompson said he's been given no explanation for the tougher guidelines. He's recommending public health precautions anyway.
"We're going to treat it, and we want municipalities to treat it as a human case, even though the state will not count it. That means if you need to do ground spraying –– any public health follow up in that area –– we agree that is the appropriate recommendation."
Thompson said while the criteria for people may have changed, criteria hasn't changed for mosquitoes.
He's counting on mosquitoes to be the first to show if Dallas County really is on the cusp of another epidemic. And they are trapping and testing more mosquitoes in more places this year.
So far, only a few mosquito pools across North Texas have tested positive, an indication that West Nile virus isn't as widespread this year as it was last.