Heartworm

Question
Hi Adrienne,
  I would like to know is that possible a six months old puppy to suffer from heartworm? She haven't tried any medicine that helps to protect her from heartworm. Should I buy the preventive medicine for her, or have a diagnose whether she infected by heartworm first? Thank you.

Answer
Greetings, and thank you for contacting All Experts!
Technically, yes. According to the American Heartworm Society even nursing puppies are at risk for heartworm infection! Virtually, any puppy of any age exposed to mosquitoes may have a chance of developing heartworm. Problem is, the disease cannot be detected until only months later. In order to understand this better, let's take a look at how the disease is transmitted.

Step by Step Guide of How Heart Worm is Transmitted

1)Basically, a mosquito infected with ''Dirofilaria immitis'' (the scientific name for the parasites responsible for causing heartworm), bites a young puppy.

2)Upon biting the puppy, the mosquito's mouth parts deliver the dirofilaria immitis larvae into the puppy's wound and therefore into the puppy's blood stream.

3)Once inside the puppy, it generally takes a little more than six months for the infective larvae to mature into adult heartworms.

Unfortunately, a dog can be diagnosed with heart worms only once the larvae turn into adults and according to the American Heartworm Society this means that it may take five to seven months from the time a dog is bitten by infected mosquitoes until a blood test may diagnose the disease. The most accurate test for heartworms is the antigen test. This test detects small proteins released by adult female heartworms.

The chances of your puppy being infected by heartworm are higher if you live in an endemic area. If your puppy is six months old now, the chances of her having heartworm may be slimmer since she was born and raised mostly in the winter months when mosquitos are less popular. However, nowadays, vets recommend putting dogs on heartworm preventive year round because mosquitoes have been seen around year long in several States. You can see a map of areas infested the most at this map provided by the American Heartworm Society;
http://www.lawestvector.org/images/Mosquito/heartwormdist.gif

You can also find answers to many other questions about heartworm at this reference link;
http://www.heartwormsociety.org/pet-owner-resources/faqs.html#q16

Therefore, if you are concerned, I would recommend having your puppy tested with an antigen test and then have her put on heartworm preventive to play it safe. You must have your dog tested first in order to have the preventative prescribed. Giving heartworm preventative to a dog already infected by heartworm can be risky. - I am not sure what breed your dog is but consider that Collie breeds are more susceptible to toxins found in heartworm preventatives, but this often takes place when they are dosed incorrectly-  I hope this helps, my very best wishes!