West Nile Virus found in Lake County
LAKE COUNTY – One of the first two confirmed equine cases of the West Nile Virus in Montana for 2018 occurred in Lake County during early August.
The Montana Department of Livestock said they received notice of the virus in Lake and Musselshell Counties. The virus was also detected in mosquitoes at surveillance pools in Cascade, Hill, and Lewis and Clark Counties.
Doctor Tahnee Szymanski, assistant state veterinarian, said the Lake County case occurred at the southern portion of the county. Montana typically sees cases of West Nile Virus through late summer and into the fall, according Szymanski.
The Montana Department of Public Health and Human Services reported that the first human case of the West Nile Virus for 2018 was found in Cascade County.
The Montana Department of Livestock information states that the virus affects humans, equines, and birds. The virus is spread through the bites of infested mosquitoes, and horses cannot transmit the virus directly to people.
“Detection of the disease in horses and mosquitoes in Montana serves as an important reminder for people to take steps to prevent West Nile infection,” the departments states.
In horses, West Nile typically causes fever, loss of appetite, weakness, muscle or muzzle twitching, and drooling.
“There is no direct treatment for the virus in horses, but vaccination is highly effective in preventing the disease. Horses that are vaccinated rarely die or are euthanized because of the disease,” Szymanski said. “Vaccination is typically administered in the spring, but may offer some protection even this late in the season. Work with your veterinarian to determine if your horse could still benefit from vaccination.”
The department suggests using a topical insecticide and eliminating standing water to help decrease exposure to the virus. Keeping horses away from irrigated pastures and water sources from dawn to dusk was another suggestion as the insects are most active during that time.
The DPHHS also reminds people to take steps to avoid mosquito bites to prevent infection of West Nile Virus.
“While mosquitoes found in Montana are unable to transmit other diseases like Zika virus, they are able to transmit WNV,” according to the DPHHS.
“When infected with WNV, about 4 out of 5 people will not have symptoms and will develop immunity after clearing the infection. Among the 1 in 5 individuals who develop the illness, they will generally experience mild symptoms that may include headache, body aches, joint pain, vomiting, diarrhea, or a rash.”
One person in every 100 will develop serious symptoms that might include infections in or around the brain, which is known as neuroinvasive disease, according to the DPHHS. In Montana, 11 cases of the West Nile Virus were reported in 2017, and eight of those cases were mild. Three cases resulted in neuroinvasive disease. Montana didn’t have any deaths from the virus in 2017, but deaths were reported in previous years.
“Currently, no vaccine or specific treatment exists for a person at risk or ill with WNV. If someone develops any of the symptoms, they should see their healthcare provider for evaluation and care,” the DPHHS states.
The department created “the four D’s” of West Nile Virus prevention for humans to reduce the chances of mosquito bites. 1. DEET: Use insect repellent such as DEET or picaridin. 2. Drain: drain standing water around your house to prevent mosquito breeding. 3. Dawn/Dusk: mosquitoes are most active during dawn and dusk. Stay inside or take precautions to prevent mosquito bites during these times. 4. Dress: when possible, wear long sleeved shirts and pants to protect yourself from bites.