Amanda Teixeira
Worms can be transmitted from dogs to humans. To protect yourself and your dog, you need to have your pet checked and dewormed regularly.
Roundworms in dogs
Roundworms are distributed worldwide and not only infest the intestines of dogs but can also damage other organs. The animals are infected, among other things, by ingesting the eggs of roundworms. There is a high risk of infection with roundworms wherever there are many animals, for example in dog parks.
Dogs ingest the worm eggs by licking the area around them or by eating feces. The roundworm eggs then penetrate the dog’s intestinal wall and travel with the blood first to the liver, then via the heart to the lungs before being transported via the trachea to the gullet and swallowed. In the dog’s intestines, they then develop into sexually mature roundworms that are up to 20 cm long.
Since some of the roundworm larvae get back from the lungs into the bloodstream and other parts of the dog’s body such as the muscles or teats, puppies can already be infected in the womb or through their mother’s milk.
Tapeworms in dogs
The most common tapeworm that infects dogs in Europe is the cucumber seed tapeworm. Unlike other tapeworms that infect dogs via prey such as mice (e.g. fox tapeworm) or raw meat, the cucumber seed tapeworm uses fleas and lice as intermediate hosts. The infectious tapeworm stages reach the dog’s intestine via infected fleas or lice, which are swallowed by the dog during grooming, where they develop into adult worms, which can grow up to one meter in length.
At the rear end, the tapeworm then cuts off individual limbs in which the infectious worm eggs are located. The infested dog then excretes these with the feces. Some of these tapeworm segments already burst in the dog’s intestinal tract, so the infectious eggs are already released in the intestinal tract.
Are worms in dogs also contagious to humans?
In principle, it is possible for roundworms and certain tapeworms to be passed from dogs to humans. In the case of roundworms, infection occurs via the ingestion of the infectious worm eggs from the environment, in which they first have to develop into infectious stages. It is therefore important to prevent environmental contamination from roundworm eggs, for example by collecting dog waste and disposing of it with household waste.
However, with certain tapeworms, such as the small dog tapeworm (Echinococcus granulosus) or the dangerous fox tapeworm (Echinococcus multilocularis), the eggs excreted in the faeces of infected dogs are directly contagious. Therefore, intensive worm control and control should be carried out, especially in dogs that take in rodents or are fed raw meat.
How do you recognize worms in dogs? Symptoms and Evidence
As a rule, a worm infestation is difficult for dog owners to recognize. Especially with tapeworms and roundworms, visible symptoms often only appear when the infection is severe or the infection has existed for a long time.
Basically, an infestation with roundworms rarely causes symptoms in adult dogs, but puppies can become seriously ill. Symptoms of a heavy infestation of dishworms include:
- indigestion
- bad general condition
- undersupply
- lethargy
- susceptibility to disease
- constipation
- to acute intestinal obstruction with fatal consequences
It is a clear indication of worms if you find flat, whitish, sometimes mobile structures in the dog feces. These could be tapeworm limbs.
A worm test can be used to determine whether the dog is suffering from worms. This worm test is a stool test. There are special worm tests that you can easily send to a laboratory. This is how the Wittis worm test* works, for example. Although this gives dog owners clarity, Amazon buyers complain that the result often arrives later than announced. Your veterinarian can also check your dog for worms.
However, a fecal examination as a worm test does not offer absolute certainty! Only adult worms produce eggs, so they don’t detect an infection at an early stage. Also, eggs are not released continuously. This is why false-negative results are often obtained.
Dewormers for dogs
There is a wide range of preparations that differ, among other things, in the spectrum of worms they are effective against. In addition, there are antiparasitics that simultaneously combat a number of other pathogens such. B. ticks and fleas are effective. The veterinarian can therefore recommend a suitable deworming agent depending on the infestation.
The deworming preparations usually work for about a day after application and kill any worms that are present during this period. There is then no protection against a new infection with worms. It is therefore important that the dog is regularly examined for worm infestation or dewormed in accordance with the risk assessment and after consultation with the veterinarian.
Dog deworming: how often?
How often a dog needs to be dewormed depends on many risk factors. ESCCAP (European Scientific Counsel Companion Animal Parasites) divides dogs into risk groups from A to D, with Group A being the least vulnerable and Group D being the most vulnerable. In order to find out which risk group a dog belongs to, the following questions must be answered:
- Is your dog allowed to roam freely? If yes, is the run unsupervised?
- Does your dog have contact with conspecifics who do not live in the same household?
- Does your dog eat carrion or feces from other dogs?
- Does your dog eat prey (mice or similar)?
For dogs in risk group A, it is usually sufficient to be dewormed once or twice a year against tapeworms and roundworms or to have their feces examined. If your dog belongs to risk group D and there is a high risk of infection due to close contact with the family (especially with small children), a monthly deworming or fecal examination can be useful. However, the individual risk for each animal must be determined in consultation with the veterinarian, so monthly deworming cannot be recommended across the board.