EL PASO, Texas (KTSM) — As more rain, and thus standing water, is expected in the Borderland, veterinarians in the area are reminding pet owners to keep their pets up to date with their heartworm medication.
Heartworm is a serious disease that can prove fatal in pets including dogs, cats and ferrets. The disease is caused by a parasite named Dirofilaria immitis that are dispersed via mosquito bite. According to the Food and Drug Administration (FDA), the worms spend their lives in a host’s heart, lungs and associated blood vessels.
“We just want to make sure people get their pets tested and on a preventative,” Dr. Jacqueline Hernandez, a veterinarian at the Vista Hills Animal Hospital in East El Paso, told KTSM 9 News. “It’s never too late to get them on a preventative.”
It’s important to note that heartworm disease is not contagious and only spread from a mosquito bite.
Heartworms release their offspring into a host’s bloodstream once infected and it takes about six months for infective larvae to mature into adult heartworms. The lifespan of a heartworm ranges between five and seven years. Adult heartworms resemble cooked rice noodles, with males growing to about 5 inches and females around 11 inches in length.
The earliest larvae can be detected in the blood is about six months after an infected mosquito bite.
“Most of the time, dogs are atypical, meaning that they don’t have clinical signs,” Hernandez said. “Most dogs are diagnosed after we perform a heartworm test that we recommend when they come in for their annual visit.”
Hernandez urges pet owners in the Borderland to have their pets tested for heartworms and put on a preventative, especially residents in the Upper and Lower Valley areas of El Paso where standing water from rain and irrigation is common during the summer months.
Pet owners can obtain a prescription for heartworm preventative from their vets, which are administered monthly as a chewable or non-chewable tablet, liquid or topical. Veterinarians can also give a shot under the skin every six to 12 months.
If a dog, cat or ferret is infected with heartworms, symptoms can range in severity based on how long the animal has been infected, as well as how the host’s body responds to the parasite.
There are four classes of heartworm disease, with severity level climbing as the class ascends:
- Class 1: No symptoms, or sometimes mild symptoms like a slight cough
- Class 2: Mild to moderate symptoms that include an occasional cough and being tired after some activity
- Class 3: More concerning symptoms, including a persistent cough, tiredness after light activity, and appearing ill. Difficulty breathing and heart failure are not uncommon. Changes in the heart and lungs are often visible through a chest x-ray during Classes 2 and 3
- Class 4: This stage is called “caval syndrome” and is when a collection of heartworms called the worm burden blocks blood flow. Caval syndrome can be fatal and require rapid surgical removal — the only treatment option at that stage. Most dogs do not survive caval syndrome, even with surgery.
Caval syndrome does not occur in every dog with heartworms but can progress and damage the organs if left untreated.
Treating heartworm is physically difficult for the animal and financially for the pet owner. The treatment can sometimes be toxic to a dog’s body and cause complications like pulmonary embolisms or blood clots in the lungs.