I have 3 dogs, and one of mine has neurological issues, and severe low weight problems, and weakness and atrophy in her back legs, and it started when I stared giving her the heartworm meds. I know heartworms are dangerous, but I also can't accept that the side effects of the meds are just as dangerous. I am trying to find a way to keep them safe without causing equal but different damage.

Cathy
when she first came home

and I had a whole response typed up but not enough coffee and too much going on this morning it makes more sense to not go there. :0)

while the MOSQUITOS won't die off if there are no hard frosts, the L1 & L2 heartworm larvae inside them will not develop into the L3 stage necessary to infect a dog. The heartworm microfilariae need temperatures around 60 degrees for at least 30 days or they will not develop before the mosquito dies of old age around 30-35 days. So those first few mosquitos you see when temperatures start to rise CAN NOT infect your dog with heartworm. They can bite a dog with L1 heartworm microfilariae, and carry it, but even if it's warm enough for the mosquito to live, if it does not stay 60 degrees long enough the heartworm inside it will die. You are essentially poisoining your dog to kill bugs that can not exist yet. There are ceratin places in this country where heartworm disease is very rare, and it's questionable wether or not the meds are ever necessary.
Every dog should be tested yearly. One of the #1 items on the list of problems associated with heartworm meds is that it doesn't work. The med is not a preventative but an insecticide that kills the microfilariae before it reaches adulthood. It is dangerous for the dog to kill all them at once and they need to be closely supervised during the process.
Heartworm meds are NOT without their risks. The FDA does approve of their use, but NO long term studies have been done to test their safety. There are a lot of vets who feel that the increase in cancers and heart disease, and liver disease is due to the increase of yearly vaccinations and heartworm med use in the past few decades. If the vaccines and heartworm meds were so effective, our dogs should be living longer and longer, and they are not. Now they are dying of cancer and liver and kidney failure instead.

Cathy
when she first came home

I understand it better.

we move a lot being in the military and there is a heavy military population up here with dogs. I don't know if all those dogs coming from different areas of the Country are all up to date with their prevention and it only takes ONE mosquito to infect your dog.

Also if you don't get a few good days of a hard frost, the mosquito's wont' die off. Their larva does not die off in the winter either, they just lie dormant and wait for warmer weather to come out and be adults, breed and start all over again.

I don't test every year unless I miss any doses. While heartworm is treatable, it's a hard and difficult treatment for the pet and I would rather make sure mine are covered than have to go through that. I use Sentinel year round on them both and Revolution on my cat. With cats, while heartworm is not as big of a concern, recently it's been shown that ONE worm can kill a cat. What is interesting about cats (Ok, I think it is LOL) is they actually produce an antigen that kills heartworm larva where dogs do not.

Scary stuff that is preventable.

My vet recommends it all year also, but he also insists on yearly testing. If I lived in Vermont,(and I used to live in MA and RI) I would NOT do heartworm preventitive year round. I would test though, yearly if not every 6 months.
It is a poison that kills the heartworm microfilariae, and those MF's HAVE to live inside a mosquito to be transmitted to your dog. Once in the mosquito, if the temp does not stay at a minimum of 60 degrees, day and night, the MF will die.
You have a long harsh winter, there is no need to give your dog poison to kill bugs that the cold weather has killed for you.
The map is a guideline, and you have to consider your own micro-climate as well. It says I need to start in June, but I know that my particular tiny spot is sheltered and warmer, so I will start in April or May. I also have IDEAL conditions for heartworm infestations: tons of swampy mosquito breeding ground, and tons of animal hosts to perpetuate the cycle.
Vets want you to do it year round for several reasons.
Many people forget things, and it's easier to remember once a month for them.
It is a source of income for them.
A lot of them, mine included, feel that it is VERY safe, and signifigantly better than the dog getting a case of heartworms.

Cathy
when she first came home

My vet did bloodwork on Maude and put her on heartworm preventative and said instead of testing every year to keep her on it all year. We live in Vermont and from what your map indicates she only needs the treatment Started in July and last does in Oct. Does she need to be retested every year? Also my puppy was born in November and she said I should start her on the preventative in April. It seems like I will be treating her when it is not necessary and should discontinue Maude until July. Please let me know if I am reading this right. Thank you, Susan