For many years, we have recommended heartworm prevention for all dogs in almost every region of the country – and it was simple. We recommended giving the preventive medication every month, and your dog wouldnít contract this potentially fatal disease. However, long-term studies show a problem. The incidence of heartworm disease continues to go up, instead of down. In just the two years from 2013 to 2015, there was a 166 percent increase in reported positive heartworm cases, according to the Companion Animal Parasite Council. Additionally, the American Heartworm Society has tracked the geographic spread of heartworm disease and its increased prevalence in several regions of the country to all 50 states.The heartworm society continues to recommend year-round prevention in most states, but now a study by John McCall, Ph.D., highlights the need to change the approach in fighting the rising incidence of heartworm infection in dogs. McCallís research shows the value of using a topical repellent insecticidal in what could best be called a ìdouble defenseî protocol for protecting dogs against heartworm disease and the vector ñ- the mosquito.Currently, the best tool veterinarians have for this is called VectraÆ 3D. It has been shown in studies to be more than 95 percent effective in repelling and killing mosquitoes for 28 days after treatment, and it was 100 percent effective in blocking the transmission of microfilariae (a crucial factor in the life cycle) from infected dogs to mosquitoes.While this seems like common sense, it has not been widely recommended; and, until now has not been proven to be of real-world significance. The results of this new study will literally change the way veterinarians guide dog owners to prevent this disease. The long term hope is to make a significant difference in the incidence of heartworm disease. As if we needed yet another reason to control mosquitoes, just look at the recent scary news about the Zika virus. This dangerous virus is transmitted by mosquitoes, and has drawn worldwide attention to the dangers of mosquitoes and the horrific consequences of mosquito-borne diseases.Can the Zika virus affect our pets? Frankly, we donít know. At this time, there is no evidence that dogs or cats can transmit or contract Zika virus. The studies simply have not been done. But, mosquito control is currently the best defense against Zika virus. Unfortunately for humans, the Aedes mosquito (which is the primary vector of Zika) are incredibly tough critters. They are aggressive daytime feeders and prefer people over most animals and thrive indoors or outside. The eggs of Aedes can survive dry, cold conditions for more than a year and hatch into larvae as soon as they contact water.Even here in Colorado, the larvae of these mosquitoes can remain dormant for months during cool weather and emerge as soon as temperatures increase. When water and warmth are present, the entire Aedes mosquito life cycle ñ- egg to adult ñ- can occur in as few as 10 days.The Centers for Disease Control and Prevention has ample evidence of the importance of mosquito control in limiting the potential for harm to humans. The same holds true for pets. Fortunately, we have the tools we need to combat this. I think you will now find veterinarians recommending we all use every tool possible to prevent disease transmission, which means that in addition to our normal heartworm protocols we should use aggressive mosquito control.Both for heartworm prevention and controlling the Zika virus, it is more important than ever to use something that we know has a high level of effectiveness in controlling mosquitoes. Products that are safe to put on your dogs that will effectively repel mosquitoes are not that common. Iím happy to see this research showing that VectraÆ 3D can provide an extra layer of defense against heartworm disease and even the slight possibility of Zika virus coming to our community. ————————————————Dr. Jim Humphries is a veterinarian and provides hospice and end-of-life care for pets in Colorado Springs. He also serves as a visiting professor at the College of Veterinary Medicine at Texas A&M University. He lives in Falcon with his wife, horses and Great Danes. www.MobilePetDocs.com
