West Nile activity rises around state

It was a busy week for West Nile virus detection across the state.

Two horses tested positive, one in Box Elder and one in Weber County, marking the first signs of the mosquito-borne illness this year in horses. It was also found in a sentinel chicken in Tooele County — the first detection this year in sentinel chickens.

The total number of human cases so far has now risen to five, with two cases in Salt Lake and one each in Duchesne, Uintah and Utah counties. None of the cases involves people over age 65; one case involves a child. They are all the milder West Nile fever illness, rather than neuroinvasive.

Finally, there are 37 newly infected mosquito pools: 10 in Cache County, two in Millard County, 19 in Salt Lake County and six in Uintah County.