Stubborn or resistant hookworm infections in the dog
Based on : Pablo David Jimenez Castro, DVM, University of Georgia
Ray M. Kaplan, DVM, PhD, DevPC, DACVM (Parasitology), St. George's University, Grenada, West Indies
For patient owners:
What is a hookworm infection in the dog - and how do you recognize and prevent it?
Hookworms are small but very dangerous parasites that settle in the dog's small intestine. ancylostoma caninum is particularly common . These tiny worms stuck to the intestinal wall and feed on the dog's blood. Unfortunately, you can do considerable damage, especially among young dogs or weakened animals.
How does my dog get really concerned?
The infection usually takes place via floors or objects contaminated with hook worms or larvae. Dogs can absorb the larvae when sniffing or licking - or the larvae even penetrate directly through the skin into the body, especially on the paws or on the stomach. Another option is to transfer from the mother dog to the puppies, either through milk or during pregnancy.
How do I recognize a hookworm infection?
The symptoms can be different. The most common signs include:
- Diarrhea (sometimes bloody)
- weight loss
- Weariness and weakness
- Blow mucous membranes (e.g. on the gums) - an indication of anemia
- Itching or skin infections when the larvae have penetrated through the skin
Special caution is required, especially in puppies: an infection can be life -threatening if not treated in time.

How is an infection found?
A hookworm infection is recognized most reliably by a faecal examination (faecal analysis). It is checked whether eggs of the hookworms are in the dog's feces. If resistant worms are suspected, additional tests can make sense, such as a so-called faecal reduction test.
How can I protect my dog?
The good news: an infection can be easily prevented! Here are some important tips:
- Regular deworming: Especially dogs with increased risk should be dewormed regularly. Your veterinarian will be happy to advise you on the right rhythm.
- Strict hygiene: Cot of the dog should always be removed immediately, especially in your own garden or in places where many dogs are.
- Puppies treat the puppies at an early stage: Mother animals and puppies should be dewormed at an early stage, since the larvae can be transmitted before birth.
- Beware of burdened environments: Avoid letting your dog run around with strong frequented dog meadows or in animal shelters.
Hookworms are serious parasites, but with the right precaution and fast treatment to get well under control. If you notice changes in the behavior or health of your dog, do not hesitate to address us! Together we ensure that your four -legged friend stays healthy and well.
More detailed: background & pathophysiology
In recent times, cases of multi-resistant (MDR) hookworms ( Ancylostoma caninum ) have been observed, which are resistant to all three large anhelminthic classes. Originally, these resistant parasites seem to have developed in Greyhound breeding and racing knowledge. In the meantime, however, MDR hookworms are also increasingly appearing in other dog breeds.
Life cycle: Female hookworms produce up to 10,000 eggs every day. Within about five days, these eggs develop into infectious larvae (L3), which can be absorbed orally or percutaneously. After the infection, the larvae hike through the blood into the lungs, reach the trachea over the bronchi, are coughed up and finally swallowed so that they grow into adult worms in the intestine.
Part of the larvae migrates in muscles and organs, where they remain in a rest phase ("hypobiotic"). These larvae can be activated later, for example during pregnancy or by "larval leakage" (continuous release from tissue into the intestinal lumen).
diagnosis
In order to differentiate whether persistent infections are based on "larval leakage" or resistance, three diagnostic methods are available:
- FaCalei reduction test (FECRT)
- In vitro bioassay (specialized laboratories)
- Molecular test procedures (specialized laboratories)
Implementation of a faecal reduction test (FECRT)
FECRT is the most practical method:
- Collect fecal samples before and after treatment.
- Use quantitative methods (e.g. McMaster or mini-flotac).
- Ideally repeat each test twice to increase the accuracy.
- Calculation of the percentage egg reduction takes place by comparing the eggs per gram (EPG) before and after treatment.
Recommended periods for the post-reaction-fecrt:
- Pyrantel: 10–14 days
- Fenbendazole/Febantel: 14 days
- Moxidectin: 14 days
Interpretation of the FECRT results
- <75 % reduction: resistance very likely
- 75–89 %: Resistance Probably
- 90–95 %: suspected of reduced effectiveness (unclear)
- 95 %: Therapy is considered effective ("larval leakage" probably)
Therapy & aftercare
Treatment for resistant infections
If resistance has been proven (<75 % FECR), a combination therapy is recommended:
- Febantel (25 mg/kg Po) + pyrantel (5 mg/kg Po) + Praziquantel (5 mg/kg Po) + MoxIdectin (2.5 mg/kg topical) or or
- Fenbendazole (50 mg/kg Po, daily for 3 days) + pyrantel (5 mg/kg Po) + MoxIdectin (2.5 mg/kg topical)
If this combination is ineffective, MDR-MoxidiTin resistance could exist.
Emodepside - outside of admission
- Only if combination therapy fails.
- Emodepside (1 mg/kg Po) shows a high effectiveness against MDR hookworms.
- Currently only approved for cats. Oral use in the dog is extremely careful and requires strict dose calculation.
- Dogs with MDR1 mutation have an increased risk of side effects.
Dosage:
Dog (kg) × 1 mg/kg ÷ 21.4 mg/ml = volume (ml)
- Example: 4 kg dog receives 0.19 ml
- Example: 30 kg dog receives 1.4 ml
Follow -up & environmental hygiene
- Regular monthly FECRT controls
- Immediate removal and disposal of feces prevents environmental contamination.
- Eggs need at least five days to get infectious, so take care of the fellow of the fellow every few days to prevent new infections.
Attention: Reinfections with resistant worms can accelerate the development of resistance.
FAQs for hookworm infections in the dog
How dangerous is a hookworm infection really for my dog?
A hookworm infection should not be taken lightly, since these parasites can cause considerable damage to the dog's body. The worms attach themselves to the intestinal mucosa and suck blood there. In young dogs and puppies in particular, this can lead to threatening anemia (anemia) because their body does not yet have enough blood reserves to compensate for this loss.
Adult dogs are also not certain before the consequences: chronic diarrhea, weight loss and general weakness can severely affect the everyday life of their dog. In addition, infected dogs outgoing eggs, which in turn can infect other dogs. If resistant hookworms are involved, the treatment becomes even more complicated. That is why it is important to take symptoms seriously, to take advantage of veterinary help at an early stage and to pay attention to good provision. So your four -legged friend stays healthy and at the same time protects other dogs!
How can I find out if my dog has hookworms?
Since the symptoms of a hookworm infection are often unspecific at first, many dog owners find it difficult to identify an infection at an early stage. The first warning signs can be a matt overall impression, loss of appetite, pale mucous membranes (especially on the gums) and recurring diarrhea - sometimes even with blood and blood.
The safest way to diagnose hookworms is a veterinary fecal examination. Your dog's feces is examined for hook worm eggs. In cases of suspicion of resistant infection, a special faecal reduction test can also be carried out to determine whether the parasites respond to common medication.
It is best to have your dog's feces examined regularly - especially if your dog has close contact with other dogs or are happy to dig in the garden. Prevention through regular controls is really the best medicine here.
Can my dog always get infected with hookworms?
Yes, unfortunately a new infection with hookworms is possible at any time - especially if your dog moves in an environment, in the contaminated feces is not carefully removed. Hook worm eggs can develop into infectious larvae in just five days under favorable conditions (moist, warm soils). These larvae are tough and can get into the body via direct contact with the floor, licking contaminated paws or even via the skin.
That is why it is important to consistently pay attention to environmental hygiene even after successful treatment: Always remove your dog's feces immediately and avoid that your dog sniffs or digs in places where many other dogs are on the go. In addition, regular dewormings help to protect the dog from renewed infections. Caution is particularly necessary for puppies and bitches with young people, since the larvae can also be transmitted via breast milk.
Why are resistant hookworms a problem - and what does that mean for treatment?
Resistant hookworms are a real challenge because they no longer reliably respond to the common worming agents. Usually so -called anthelminthics are used in an infection - medication that kill parasites in the body. However, due to frequent and partially improper use of these remedies, some hookworms have changed so that they have become insensitive.
Specifically, this means that even after an apparently correct treatment, these worms can survive in the intestine of their dog and continue to exit eggs. Therefore, a special procedure is necessary in such cases. Veterinarians then rely on a combination of several worms or alternatives such as emodepside (whereby this drug is only used in the dog in exceptional cases, since it is originally approved for cats).
The most important point: a resistant infection is not solved overnight. In addition to targeted therapy, tight -meshed control through repeated fecal examinations is necessary to ensure that the worms have actually disappeared.
How can I best protect my dog from a hookworm infection?
As so often, the prevention is the best protection! Here are a few practical measures that you can take as a dog owner:
1. Regular deworming: Talk to your vet about a tailor -made deworming scheme. Dogs in particular that have close contact with other dogs or live in risk areas should be dewormed regularly.
2. Coter disposal: Always remove your dog's feces immediately, whether in your own garden or on the go. In this way, they prevent hookworm larvae developing and infecting others (or their own) dog.
3. Puppy and mother hygiene: Deworming of the mother dog During pregnancy and lactation, the transfer of the larvae can prevent the puppies. The puppies should also be dewormed early.
4. Clean environment: Keep your dog's sleep and run-out area clean and dry. Moist and warm conditions promote the development of the larvae.
Regular faecal examinations: Even if your dog shows no symptoms, a regular examination of the kots makes sense to recognize an infection early. Create the practice - to give your patient owners! 😊 "
Summary: Hookworm infection in the dog
Hookworm infections in the dog are widespread worldwide and are a serious threat to the health of our four -legged friends. Young dogs and puppies in particular are susceptible to hookworm infections in the dog, since their immune system is not yet fully developed and they can suffer from anemia faster. The hookworm infections in the dog are caused by the parasite ancylostoma caninum , which is stuck in the dog's intestine and sucks blood there.
Typically, hookworm infections in the dog are created through contact with contaminated soil or when licking your own paws, which have come into contact with larvae. Swallowing larvae when sniffing on contaminated feces can also lead to hookworm infections in the dog. Particularly sensitive: Even the transmission via breast milk is possible in the dog's hookworm infections.
The symptoms of hookworm infections in the dog can vary. Many dogs show diarrhea, sometimes even bloody, as well as weight loss and fatigue. A striking sign of hookworm infections in the dog are pale mucous membranes that indicate anemia. Therefore, owners should be attentive to identify hookworm infections in the dog early.
the veterinarian is necessary to diagnose hookworm infections in the dog . The worm eggs can be demonstrated in the feces with special detection methods, which means that hookworm infections in the dog can be safely diagnosed. Especially with suspected resistant parasite tribes, a faecal reduction test is recommended in order to identify hookworm infections in the dog.
Treatments against hookworm infections in the dog should always be carried out under veterinary guidance. In most cases, well -proven worm agents help. It becomes more difficult when it comes to resistant hookworm infections in the dog - then a combination of different active ingredients is often necessary. Here it is important to consistently monitor hookworm infections in the dog and take further measures.
Even after successful therapy, the danger is not averted: hookworm infections in the dog can reappear at any time by recording the larvae again. Regular control and faecal examination helps to recognize hookworm infections in the dog early and to act quickly.
A good hygiene practice is part of the dog's prevention of hookworm infections in the dog. Dog owners should quickly dispose of feces so as not to burden the environment and minimize the risk of hookworm infections in the dog. Moist and warm environments promote the development of the larvae and significantly increase the risk of hookworm infections in the dog.
Particular caution is required for bitches during pregnancy, since hookworm infections in the dog can also be transferred to the puppies via the milk. Preventive deworming of the mother can help to avoid hookworm infections in the dog in the litter.
It is also important to inform dog owners so that the dog's awareness of hookworm infections in the dog. Because only those who are well informed can prevent hookworm infections in the dog. Regular visits to the vet and consistent precautionary measures are the best protection against hookworm infections in the dog.
Dog owners should also be vigilant for trips abroad, as hookworm infections in the dog occur particularly frequently in some regions. Prophylactic treatment before and after the trip can help prevent hookworm infections in the dog.
Owners who live in multi -dog households should be particularly attentive, since hookworm infections in the dog can be easily passed on within the household. Therefore, if you suspect hookworm infections in the dog, all dogs should be treated at the same time.
In summary: hookworm infections in the dog are to be taken seriously, but with a combination of mindfulness, hygiene, regular veterinary controls and targeted treatments, hookworm infections can be easily handled by the dog. So your dog stays healthy - and hookworm infections in the dog don't even become a problem.
Literature & further information
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