Middle River Veterinary Hospital

252 Rolla Mill Road
Verona, VA 24482



Intestinal Parasite Control

Roundworms & Hookworms


Most pet owners are familiar with heartworm prevention & heartworm disease. I'm sure you've heard, "Please keep your pet on heartworm prevention year round." Did you know your heartworm prevention is also protecting your pet from intestinal parasites? This critical and extra benefit helps to keep our pets and families healthy. So what are these parasites and how do they impact us?


All heartworm preventatives on the market today, to my knowledge, protect our dogs and cats against round and hook worms. These are common intestinal parasites that are zoonotic, in other words, people can get them.


Dogs & cats pass these worms through the fecal - oral route. It's a rather complicated cycle, but in summary they eat or lick stuff that has been contaminated with infected feces. The larval eggs get into their bodies where they migrate to the gastrointestinal tract and become adult worms. From there they reproduce, making more eggs and then the animal obligingly defecates eggs to start the cycle over again.


Click here for a cool diagram of the round worm life cycle.


Small children, like our pets, are not the most discriminating when it comes to putting things into their mouths. So they are at highest risk of getting round and hook worms. The worms can also enter both people & pet bodies through the skin. So if you have an infected animal pooping in your yard it's possible to get infected. The larvae migrate through your tissue on way to the intestines, but some get lost and can end up anywhere inside you or your pet. Really disturbing! This is called viseral larval migrans. For gorey images of what that can do, just Google it. Or keep all of your pets on heartworm prevention year round.


So what do these worms do besides crawling through your tissues? Hook worms latch onto the mucosa of the intestine causing blood loss and anemia. It's often life threatening in young puppies and kittens. Roundworms become so numerous you may see animals with gastrointestinal signs such has vomiting, diarrhea, inappetance, poor growth and lethargy if they are young enough. Breeding females pass both kinds of worms to their offspring through their milk or in utero while pregnant. Most of our pets have encysted larva in their tissues that become active during pregnancy. It's believed all puppies and kittens are born with round and hook worms. That is why we deworm them so often until they get old enough to start heartworm prevention.


So why use prevention year round? Some people take their pets off heartworm prevention in the winter since there are few to no mosquitoes then, unless you travel to warmer climates. Mosquito's transmit heartworms, but, some eggs from round worms can survive in freezing temperatures in the environment for months, so continued year round coverage is critical.


What other parasites are covered? Some heartworm preventatives also protect against whipworms in dogs. This worm is not zoonotic to people, but can cause significant gastrointestinal issues in adult dogs. Unfortunately tapeworms are not prevented by heartworm prevention and needs a separate dewormer if that's a problem.


So what's the bottom line? To protect your pets, family, friends and neighbors from round & hook worms, keep your pets on heartworm prevention year round! We here at Middle River prefer Interceptor for dogs and Revolution for cats.