Although the weather in Southwestern Ontario seems quite confused lately regarding whether it wants to be winter or spring, at least we’re still a few months off from having to worry about mosquitoes and the viruses they carry once again.  Warmer parts of the world, however, are in the midst of their mosquito season, and some chickens are lending a hand to give people in the area a "heads up" about what’s around.

The Health Department of Western Australia has detected Murray Valley encephalitis virus (MVEV)  in chicken flocks in East Kimberley.  The department has also tested and found the virus in its sentinel chickens in Wyndham and Kununurra.  These sentinel birds play an important role as an early warning system when viruses like MVEV are circulating in the area.  Just like West Nile virus, MVEV typically circulates between birds and the mosquitoes that like to feed on them, but problems occur when the same mosquitoes start to bite people (or other susceptible animals such as horses), particularly when there are a lot of mosquitoes, like when the weather is very wet or when there’s been flooding.  Although most people who are infected with MVEV or WNV fight off the virus with no difficulty, or may simply develop short-term, non-specific signs of illness like mild fever and malaise, in some people these viruses can cause severe infection of the brain (encephalitis) and may even be fatal.

Knowing that MVEV has been found in these "guardian" chickens lets people know (via warnings issued by the health department) to take extra precautions against mosquito bites, such as:

  • Staying indoors during peak mosquito activity – dusk and dawn
  • Wearing protective clothing including long-sleeves and long pants
  • Applying insect repellent

In North America, you can pretty much substitute West Nile for Murray Valley in a case like this.  Sentinel chickens have been used to provide early warnings of circulating WNV here, before cases are detected in people or horses.  Another means of early detection that is also used is testing pools of mosquitoes directly.

It just goes to show you can still be an important part of the country’s defenses, even if you’re a little chicken :p

(click image for source)