The McCone County Health Department and the Montana Department of Public Health and Human Services are reporting Montana’s first human death from West Nile Virus (WNV) for 2016.


This case brings the total number of West Nile Virus (WNV) cases reported in Montana to six for 2016. Previously, four cases were reported in Dawson County and one in Garfield County. Additionally, several horses and mosquito pools, predominately in eastern Montana, tested positive for WNV.

The deceased, an adult McCone County resident, passed away from complications related to West Nile Virus infection. The individual had no history of travel outside the state within the past month and the infection was believed to be locally acquired.

“This is an unfortunate reminder that infection from WNV can have serious consequences,” said DPHHS Director Richard Opper. “We want to remind people to take precautions and protect themselves.” Nationally, 406 human cases of WNV have been reported to the Centers for Disease Control and Prevention thus far in 2016, including ten deaths.

WNV is transmitted to humans by infected mosquitos through bites. Most, about 4 out of 5, people infected will experience no symptoms and become immune to the WNV infection. About 1 in 5 infected people develop a low grade fever, headache and muscle aches that begin a week or two after becoming infected. Generally, no treatment is needed.

However, in less than 1 percent of infected people, serious, life-threatening symptoms develop including headache, rash, high fever, stiff neck, mental confusion, and other symptoms. Individuals who develop any of these symptoms should see their health-care provider immediately.

Mid to late summer is a high-risk period for WNV and public health officials encourage everyone to take steps to avoid mosquito bites and prevent infections. Public health officials want to remind the public that while local transmission WNV is a concern in Montana, local transmission of Zika virus is not. In fact, the mosquitos that carry Zika virus have not been found in Montana or neighboring states.

To minimize risk of WNV, experts recommend reducing mosquito populations by removing mosquito breeding areas in and around the home. Simple steps such as draining bird-baths, wading pools or any container with still water every few days will minimize breeding sites.

Because it is not possible to eliminate all breeding sites, people are reminded to follow specific recommendations to avoid being bitten. This includes wearing and safely using insect repellent when outdoors and wearing pants and long-sleeved shirts when possible.

The 4 D’s of West Nile Virus prevention should be followed to reduce the chance of mosquito bites.

Dusk / Dawn: Peak mosquitos biting hours are dusk to dawn.  Limit outdoor activity during those times. If you must be outside, be sure to protect yourself from bites.

Dress: Wear long-sleeved shirts and pants to reduce the amount of exposed skin.

DEET: Cover exposed skin with a repellant containing the chemical DEET, which is most effective against mosquito bites.

Drain: Empty any containers holding standing water because they can be excellent breeding grounds for virus-carrying mosquitoes.

The number of WNV human cases in Montana varies from year to year. Over 200 cases were reported in 2003 and 2007, but generally the average is about 10 reported human infections each year. “No one can predict the severity of WNV season,” said Christine Mulgrew, DPHHS WNV Program Manager. “But we can protect ourselves from mosquito bites and eliminate breeding sites around your home.”