Internal parasite control for dogs and cats

Puppies and kittens often become infected with parasites either in the womb or through milk. Due to this fact, internal parasites can cause diseases in puppies and kittens at a very early age, and they can start shedding eggs and larvae as early as 2 to 3 weeks after birth.

When humans ingest parasites from the environment, they rarely remain in the intestines. The larval form of the parasite migrates into the tissues of the host (human). Depending on where the larvae localize within the organs or tissues, clinical symptoms are determined.

When parasite eggs are ingested by humans, they end up in the intestines, where they hatch. Then, the active larvae migrate through the liver, lungs, and other organs and tissues, where they cause damage and elicit an allergic response from the body. In children, disturbances in vision and neurological symptoms are most commonly observed. Roundworms in dogs and cats from another group – Ancylostoma caninum, A. braziliense, A. tubaeforme, and Uncinaria stenocephala, can also infect humans when larvae are ingested through the mouth or through direct penetration through the skin.

Cutaneous larva migrans syndrome is mainly characterized by progressive intense itching and linear lesions on the skin outlining the movement of the larvae. Some of the larvae can penetrate deeper into the tissues and cause symptoms of visceral larva migrans or migrate to the intestines and cause enteritis.

Veterinarians can protect you!

In most cases, people can prevent potential infection through ordinary measures of good hygiene, regular deworming of pets, and restricting children’s access to areas likely to be contaminated with dog and cat feces.

Many pet owners are unaware that intestinal parasites in dogs and cats can infect humans. Therefore, they do not take any precautions. Veterinarians are in the best position as specialists to educate pet owners on how to protect themselves and their entire families from such infections.

Preventative deworming

Deworming pets is the most effective method for preventing environmental contamination with eggs and larvae and protecting humans from diseases. Deworming is recommended for puppies, kittens, and their mothers because they are reservoirs for parasites. To effectively protect the environment and humans, deworming should begin soon after birth.

For puppies, deworming should start at 2 weeks of age and be repeated at 4, 6, and 8 weeks. Since prenatal (in utero) infection of kittens is not observed, egg shedding occurs a little later. Effective deworming of kittens should begin at 6 weeks and be repeated at 8 and 10 weeks.

Most dog and cat owners are aware that their pets can have internal parasites such as roundworms, tapeworms, and others, and therefore, they regularly use deworming medications. These medications usually come in the form of tablets with a combined action, destroying both roundworms and tapeworms simultaneously.

It is commonly believed that deworming should be done once every 3 months. New owners of small puppies are often instructed by the mother dog’s owners to administer some form of deworming medication twice at 14-day intervals.

With cats, things are a bit different. Most indoor cats are never dewormed throughout their lives. Cat owners whose cats go outdoors usually realize that the risk of parasites is higher, but at best, they use deworming medication 1-2 times a year.

For both dogs and cats, there’s a common belief that if worms are seen in their feces after treatment, then the treatment should be repeated after 14 days. If no worms are seen, it’s assumed that the animal is “clean” of parasites.

What are the mistakes in this practice?

Let’s start with the fact that from a medical point of view, it is most correct for all small puppies and kittens aged 20 days to 6 months to be examined at least once (preferably three times – with each vaccination) for the presence of intestinal parasites. Adult dogs and cats (over 1 year old) should be examined once a year – it is most convenient for this to be part of the routine preventive check-up accompanying their annual vaccination. This examination involves taking a small amount of feces directly from the animal (it can also be brought by the owner), mixing it with a special solution that separates the eggs of the parasites, and observing the sample under a microscope. This way, it is determined whether the dog or cat has parasites and an accurate diagnosis is made – what kind of parasites they are and what is the extent of infestation. Different types of worms and tapeworms produce distinguishable eggs, and the number of eggs indirectly indicates the number of parasites and the severity of the condition.

How much time elapses from the ingestion of a parasite egg (e.g., during a walk) until it develops in the dog’s or cat’s body and starts to excrete new eggs in the animal’s feces? This depends on the type of parasite, but the shortest development cycle is 3-4 weeks or 1 month.

That’s why it’s most appropriate to conduct preventative deworming every 30 days. Only in this way can you be sure that at no time does your pet excrete eggs and therefore pose no threat to you, as well as to other dogs and cats it comes into contact with. This is the practice adopted in Western countries, such as the USA, Germany, etc. Modern medicinal products are non-toxic and practically harmless to dogs and cats. There are even those that are suitable for pregnant and newborn animals.

However, the situation with therapeutic deworming is different – i.e., when there is proven infection with a specific type of worms or tapeworms. Due to the complexity of their development, multiple treatments are necessary – 4 or 5 times over 10-14 days or more, depending on the specific parasite. Medications only act on parasites located in the intestines. None of them affect the eggs, and very few act on the migrating larvae in the body. It’s always advisable to monitor treatment with fecal examinations. If your dog (cat) lives outdoors, you’ll need to collect and dispose of their feces. Keep in mind that parasite eggs are extremely resilient in the environment, and the feces-contaminated soil can serve as a source of infection for a long time, meaning your animal will constantly be reinfected despite regular deworming. So why not show goodwill and pick up after your dog in the park and on the street every time you walk them? This is easily done with a plastic bag, into which you insert your hand, then turn it back, tie it, and throw it in the nearest trash bin. We all have a responsibility to contribute to cleanliness and reduce contamination in our environment.

Other important things you should know – medications have no preventive effect – they only work on the day they are administered. Checking feces for worms doesn’t mean the animal is “clean” – visible adult forms firmly attach themselves to the intestines, and when they die, they are often broken down by digestive juices. Additionally, the adult Echinococcus tapeworm is too small to be seen with the naked eye.

Don’t forget that indoor cats can also have internal parasites – acquired from their mother when they were kittens, from the mice they may have caught before you got them, from the soil you bring in for your potted plants or for the cat’s litter box, from the street dust stuck to your shoes, from fleas, which serve as intermediate hosts for certain types of tapeworms, and so on.

Most people think that only the dog tapeworm is dangerous to them. Undoubtedly, it is the most dangerous, but some types of worms are also very dangerous – especially for children, who are most susceptible to infection.

Only regular and properly conducted prevention and treatment will protect your pet and you from these unpleasant parasites.

Don’t forget about cleaning the environment – this should be a duty for every dog owner.