Mosquitoes Carry More Disease Than You Think


Consumer Reports just did a piece on how to protect yourself against the Zika virus. But what about your pets?

Veterinary parasitologist Dr. Dwight Bowman, professor at Cornell University, Ithaca, NY. Bowman is also on the Board of Directors of the Companion Animal Parasite Council (CAPC) says, “We don’t believe that dogs get the Zika virus.” The truth is that the birth defects that occur in people, don’t happen in dogs (as a result of the Zika virus). However, it doesn’t necessarily mean that dogs dog get the virus, and their immune systems fight it off without exhibiting symptoms, or that (at least some dogs) don’t have mild symptoms. Zika in dogs has never been studied.

After all, Zika in humans isn’t even yet fully understood.Pet expert Steve Dale writes about mosquito illnesses in dogs and people

For those in the know, the scariest thing about Zika is that it’s thought that at least half the people with the virus are asymptomatic and don’t know they’re carrying the virus. So imagine thousands of these innocent carriers without symptoms returning to the U.S. from South or Central America, or Puerto Rico. A mosquito bites them, and now picks up the virus which those mosquitoes, now infectious, share with many other previously uninfected people, including pregnant women.

It’s scary.

I chose a mosquito ridden but northern state – taking the topics out of the equation. According to the Minnesota Department of Health, here are diseases currently spread by mosquitoes in that state. Whether or not in a few months or a year  Zika is added to the list remains to be seen. Even without Zika, I think this list is too impressive right now. Currently, mosquitoes – even in the U.S., and northern states like Minnesota, carry disease.

  • West Nile Virus (WNV)
    A disease transmitted to people, horses, and birds. It is the most commonly reported mosquito-transmitted disease in Minnesota. Most people infected with West Nile virus show no symptoms or flu-like symptoms, but some (primarily elderly) have more severe illness. West Nile virus was found in Minnesota in 2002 and will remain a public health concern in the foreseeable future.
  • La Crosse Encephalitis (LAC)
    A viral disease that is transmitted by the Tree Hole mosquito. It has been responsible for an average of just only about a half a dozen each year in Minnesota, primarily involving severe illness in children.
  • Jamestown Canyon Virus (JCV)
    May be transmitted by several different species of mosquitoes throughout Minnesota, is a rarely reported cause of illness in humans. The virus is closely related to La Crosse virus, although disease is reported less frequently and any age group may be affected.
  • Western Equine Encephalitis (WEE)
    A disease transmitted to people, horses, and birds. It is caused by a virus that is transmitted by the same mosquito species that commonly transmits WNV in western Minnesota. During 1941, there was a large regional outbreak of Western equine encephalitis. In more recent years, its occurred far less frequently.
  • Eastern Equine Encephalitis (EEE)
    A rare illness in humans and horses, and only a few cases are reported in the United States annually. Many people infected with EEE virus show no symptoms but some (primarily children) have severe illness. Although cases have been reported in horses, no human cases have been identified in Minnesota.
  • St. Louis Encephalitis (SLE)
    Cases of St. Louis encephalitis are usually the result of unpredictable and intermittent localized epidemics. SLE has not been reported in Minnesota since the 1970’s. 

Pet expert Steve Dale writes about mosquito illnesses in dogs and peopleExperts concur that the above list is incomplete. It’s likely mosquitoes carry pathogens that affect people and pets which aren’t yet discovered.

Of course, mosquitoes also carry heartworm which is primarily spread to dogs, wild canines, and also domestic cats. Heartworm preventives work exceedingly well, and they’re very safe.

However, no product is perfect. And heartworm can potentially be fatal, and is expensive to treat – so avoiding heartworm is important.

The CDC suggests more than one control to prevent mosquito transmitted disease in people, so why not the same strategy for dogs?

A product called Vectra 3D (because it contains permethrin) also kills mosquitoes. What’s not commonly known is that sometimes mosquitoes prefer biting dogs to people. So, get this – if you’re in the yard or inside your own home (sometimes mosquitoes get inside, and they’re hungry), if the buzzers go after the dog protected with Vectra; they die – that means those dead mosquitoes aren’t biting people and aren’t potentially spreading disease to people, or dogs or cats or anything else mosquitoes bite.