What’s your guess?  How long do you think a female mosquito lives for?

A)    One day

B)    One to two weeks

C)    Three days

D)    None of the above

 

When I first decided to write about heartworm disease I was going to talk about why prevention is so important and show pictures of what heartworms look like.  After doing research I thought that talking about mosquitoes themselves would be more interesting and give a clearer picture of why heartworm continues to be spread by these flying parasites.

 

I wonder how many people think that a mosquito dies shortly after feeding and laying its eggs. That’s what I used to think.  What I found amazing and disgusting is how long a female mosquito can actually live for.  It all depends on the temperature and humidity but a female mosquito can live about one to two weeks.

 

After the female obtains a full blood meal, the female will rest for a few days while the blood is digested and eggs are developed. Depending on temperature this process takes about 2 – 3 days.  Once the eggs are fully developed, the female lays them and resumes host-seeking and can once again spread the infective heartworm to her prey. It only requires the bite from one mosquito to transmit this disease.

 

There is no way to tell if a mosquito is infected with the potentially deadly heartworm microfilaria.  Using heartworm prevention is the only way to prevent transmission.  Dogs not protected can become infected with heartworm by way of the puncture wound the mosquito causes.  The larvae then migrate into the body through the puncture wound and travel through the dog’s body.  When these heartworm larvae grow into adult worms they multiply and may live for five to seven years in a dog.  The worms actually take up so much space in the heart that it leads to less blood being pumped and  if enough worms are present, the heart must work extra hard to pump blood through the plugged up arteries.

 

According to a study done in 2010, dogs in Ontario appear to have the highest risk for contracting heartworm disease in Canada.   Of the 289,229 tested in Ontario, 428 tested positive for this potentially deadly parasite. This is more than a 60% increase compared to the study that was conducted in 2002.  In our region there has been a positive case reported in North Bay and Parry Sound.

*Map used with permission from Merial Animal Health