West Nile Virus Claims Two More Lives as the Season Rages On

With September approaching, and with it the final weeks of peak West Nile virus season in the United States, news of new human cases as well as deaths due to the virus continues to come in from state health officials across the country.

According to surveillance data from the Centers for Disease Control and Prevention (CDC) on the 2017 West Nile season, 43 states have reported detecting the virus in birds, mosquitoes, or humans as of August 15, 2017. So far, 209 human cases have been reported by health officials in 28 states, including 126 neuroinvasive cases and 83 non-neuroinvasive cases. The neuroinvasive cases have occurred in Alabama, Arizona, California, Colorado, Georgia, Idaho, Illinois, Indiana, Kansas, Louisiana, Minnesota, Mississippi, Missouri, Nebraska, Nevada, New Mexico, North Dakota, Oklahoma, Pennsylvania, South Carolina, South Dakota, Tennessee, Texas, and Virginia.

Following earlier news from the Mississippi State Department of Health reporting new West Nile cases in the state, on August 21, 2017, state health officials announced 2 new deaths associated with the virus as well as 12 new human cases. A press release detailing the news notes that the 2 deaths occurred in Humphreys and Forrest Counties, and that the Forrest County death involved a previously reported case. The 12 new cases occurred in Bolivar, Hinds, Humphreys, Lincoln, Madison, Noxubee, Rankin, and Wilkinson Counties, and brings the state’s total number of cases this season to 36 thus far. Mississippi saw 43 cases of West Nile and 2 deaths in 2016. While peak season for the virus occurs in Mississippi from July through September, the press release notes that cases of West Nile can occur during any time of the year.

Also on August 21, 2017, the Wisconsin Department of Health Services announced the state’s first human cases of West Nile virus of the season. The cases involve residents of Oconto and Fond du Lac Counties, and follows the news of officials having found 20 West Nile-positive mosquito pools and 63 birds with the virus that had been reported on August 16. All told, 50 Wisconsin counties have reported some form of West Nile activity so far during the 2017 season. Last season, the state saw 13 human cases of West Nile. While most human cases of West Nile tend to be reported in the months of August and September in Wisconsin, health officials urge residents to take measures to prevent mosquito bites throughout the summer and early fall. This includes wearing insect repellant, changing water in pet dishes at least every three days, and turning over items such as wheel barrows and wading pools when not in use in order to avoid the creation of breeding grounds for mosquitoes.

In California’s Monterey County, local health officials have detected the first West Nile-positive bird in the county since 2013. Because infected birds can pass on West Nile virus when they are bitten by mosquitoes, prevention strategies include monitoring avian cases. California has reported 41 human cases, 203 dead birds, and 2,040 mosquito samples positive for West Nile virus so far this year. In 2016, the state reported 442 human cases of the virus, 19 of which were fatal.

“Monterey County residents should take precautions to protect themselves from mosquito bites,” said the county’s health officer Edward Moreno, MD, in a recent statement. “West Nile virus can be a serious disease, particularly for the elderly and people with certain medical conditions like cancer, diabetes, and kidney disease.”