Heartworm Life Cycle

The heartworm life cycle begins when a mosquito bites an infected animal and ingests tiny heartworm larvae along with the animal's blood. Coyotes, wolves, foxes, and ferrets can also develop heartworm disease in addition to dogs and cats. Next, the larvae develop into an infective stage inside the mosquito. When a heartworm disease-carrying mosquito bites your pet, it transmits the larvae that develop for approximately two months in your pet's tissue. Afterwards, developing and mature adult heartworms can be found in the bloodstream, heart, and lungs. They can also produce tiny heartworm larvae that is released into the blood and is picked up by mosquitoes who repeat the process again.

Heartworm disease is serious and potentially fatal in pets. Worms can grow up to a foot long and live in your pet's heart and lungs. Signs of heartworm infection includes coughing, difficulty breathing, and lethargy.  Some pets may not show signs of the disease. Treatment of heartworm disease is difficult. In cats, there is no approved treatment. Prevention is easy. We recommend a once monthly heartworm preventative medication for dogs and cats regardless of their lifestyle. For more information about disease-carrying mosquitoes in Ventura and Los Angeles County, click here. To read about one of our patient's journey through heartworm treatment, click here.

Home is Where the Heartworm is?

Mosquitoes transmit life-threatening heartworm disease to dogs and cats. They are generally known to carry a variety of serious diseases but which mosquito species are prevalent in our community and what does this mean for the safety of our pets? Ventura County is typically home to 15 common species of mosquitoes. Of these, the species Aedes sierrensis, or Western Treehole Mosquito, is known to carry heartworm disease. These mosquitoes reside in water-filled tree holes or containers and are highly adaptable to varying weather and feeding conditions. Los Angeles County is also home to the Western Treehole Mosquito in addition to the heartworm-carrying Aedes notoscriptus species. Also known as the Australian Backyard Mosquito, this species thrives in water-filled containers in urban environments.

What does this mean for the dogs and cats in our community? They are threatened. Heartworms can grow up to 10-12 inches long and cause severe complications. In dogs, they typically live in the right side of the heart and vessels of the lungs. Our hospital has managed and treated multiple cases of heartworm disease. Last year, we treated a German Shepherd named Sam after finding heartworms in his pulmonary artery. Heartworm treatment is lengthy and Sam's severe activity restriction over the course of two and a half months was very difficult on him and his owner. We are pleased to report that Sam is currently happy, healthy, and receiving a veterinary-guaranteed monthly heartworm prevention. Click here to read more about Sam's story.

Heartworm disease is complicated. Prevention is simple. We recommend a once monthly heartworm preventative for all dogs and cats regardless of their lifestyle. The average cost for heartworm prevention is less than $9 per month. A thriving, safe community is priceless. Protect your pet now. Home is not where heartworm disease is... if we prevent it.

Find out more about mosquitoes and mosquito-related diseases in our community from the Ventura County Environmental Health Division. Learn more about mosquitoes in Los Angeles County from the Greater Los Angeles County Vector Control District.

April is National Heartworm Awareness Month

Read about Sam's story and help raise awareness about heartworm disease. Heartworm disease is life-threatening, difficult to treat, and is present in our area. Numbers of affected pets across the country steadily increases each year. Click here to view the American Heartworm Society's Heartworm Incidence Maps. Heartworm disease is transmitted by mosquitos carrying the microscopic heartworm larvae. Mosquitos are tougher than a lot of us think and can thrive even in cold or dry areas. As the disease develops in pets, adult heartworms can grow 10 to 12 inches in length and make their home in the right side of the heart and lungs. Giving your pet a monthly preventative for heartworm and intestinal parasites is like buckling your seat belt each time you drive in you car. It is a relatively simple measure that can prevent a considerable amount of damage. Annual heartworm testing is recommended in order to verify that prevention is working properly or diagnose an infection so that treatment can begin promptly.

We diagnosed Sam, a local dog from Simi Valley, with heartworm disease last September. Sam had formerly lived in northern California and was on a diligent regimen of off-brand monthly heartworm prevention. Despite this, his heartworm test came back positive and we confirmed the diagnosis with additional testing. Ultrasound showed that Sam had heartworms in his pulmonary artery.

Sam HW tx We began treatment with the only FDA approved adulticide used to treat heartworm infestations. This medication is sometimes difficult to acquire given the national demand for it. It also can cause side-effects. Sam received a series of three injections over the span of a little more than a month. During his treatment Sam experienced varying degrees of inappetence, lethargy, and diarrhea. It is extremely important that a patient's blood pressure is not elevated during heartworm treatment and for a considerable period afterwards. An elevation in blood pressure can be life-threatening as the dying heartworm could cause a blockage in a major artery. In light of this, Sam was limited to very strict confinement for two and a half months which was just as difficult on his mom than it was on him, if not more.

We want to strengthen and lengthen the bond between you and your pet. Please consider heartworm testing and prevention. Also, contact our hospital for promotions surrounding National Heartworm Awareness Month.

April is National Heartworm Awareness Month

Incidence mapHeartworm disease in pets is a problem that continues to worsen. Every three years, the American Heartworm Society (AHS) gathers data from thousands of veterinary practices and shelters to create a detailed map showing the average number of heartworm-positive cases per clinic. The lightest red zones are areas in which clinics see 1-5 cases of heartworm disease per year and the darkest red zones indicate areas in which heartworm disease is very prevalent. Clinics in these areas can see 100+ cases of heartworm disease per year. Just in the past few years, our hospital has diagnosed a couple of cases of heartworm disease in local pets who had not traveled outside of the Moorpark area whatsoever. Canine and feline heartworm disease develops when a dog or cat is bitten by a mosquito carrying microscopic heartworm larvae. As a mosquito feeds, these larvae are deposited into the bloodstream. As heartworm disease develops, adult heartworms can grow 10 to 12 inches in length and make their home in the right side of the heart and lungs. Heartworm disease is life-threatening, difficult to treat, and present in our area. Heartworm disease is a big problem with a simple solution. Giving a single medication once a month can help keep your dog or cat safe from heartworm disease. Call us to find out about our promotions surrounding heartworm testing and prevention during the month of April. If you would like more information about heartworm disease, prevention, and testing you can click here to visit the U.S. Food and Drug Administration's website or click here to visit the American Heartworm Society's website.

Heartworm Disease: Prevent it Now

Heartworm disease is life threatening, difficult to treat, and is present in our area. But there's good news, giving a single medication once a month keeps your pet safe from heartworm disease as well as other harmful internal parasites. Canine and Feline heartworm disease develops when a dog or cat is bitten by a mosquito carrying microscopic heartworm larvae. As a mosquito feeds, these larvae are deposited into the bloodstream. As heartworm disease develops, adult heartworms can grow 10 to 12 inches in length and make their home in the right side of the heart and lungs which can result in devastating consequences. Mosquitos are a lot tougher than most people think. They can thrive even in dry areas like our own due to pockets of standing water such as outdoor water bowls, sprinkler systems, and bird baths. Before starting your pet on heartworm medication, a simple heartworm test is required to ensure that heartworm disease is not already present. If preventative heartworm medication is administered to a heartworm infected pet, a life-threatening reaction may occur. Furthermore, we recommend yearly heartworm tests for pets who are taking preventative heartworm medication. Unfortunately, no medication is 100% effective 100% of the time in pet or people medicine. Annual testing with either verify that the heartworm prevention is working properly or diagnose an infection in the early stages so that treatment can begin promptly. Click on the link below to view the American Heartworm Society's 2013 Heartworm Incidence Map to see the prevalence of heartworm cases in our area and across the country. AHS-2013-Incidence-Map