Lungworm Infection in Dogs (Canine Angiostrongylosis, Angiostrongylus vasorum Infection)

  • Synonyms: Angiostrongylus infection
  • Occurrence: common
  • Location of disease: Chest
Author: Dr. med. vet. Gisa Löwe | Last modified: 15.10.2026
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Definition

Canine angiostrongylosis is a parasitic infection in dogs caused by the lungworm Angiostrongylus vasorum, which affects the dog’s heart and lungs and can lead to severe health complications.

The most important facts at a glance

Canine angiostrongylosis is a parasitic infection caused by the nematode Angiostrongylus vasorum, which affects dogs and other canids. The parasite has a complex life cycle that includes snails and slugs as intermediate hosts. Dogs become infected by consuming these intermediate hosts or contaminated materials. After infection, the larvae migrate through the dog’s body to the pulmonary arteries, where they mature into adult worms and lay eggs. These eggs develop into larvae that are excreted through the respiratory tract. Symptoms of infection may include sneezing, cough, nasal discharge, and in severe cases, neurological problems. Diagnosis is made through stool examinations and serological tests. Treatment includes antiparasitic medications such as moxidectin and milbemycin, as well as supportive measures for severe infections. The prognosis depends on the severity of the infection and the speed of treatment. Preventive measures include avoiding contact with snails and regular deworming. Research focuses on improving diagnostic methods, developing treatment options, and preventive strategies such as vaccines. International research, supported by modern technologies, aims to improve disease control. Early diagnosis and treatment are crucial to increase the chances of complete recovery.

Causes

Angiostrongylus vasorum is a nematode that infects dogs and other canids as its definitive host. The life cycle of this parasite is complex and involves intermediate hosts such as snails and slugs, which ingest the worm’s larvae. Dogs become infected by consuming these intermediate hosts or contaminated materials.

After ingestion, the larvae enter the dog’s body via the digestive tract. They migrate through the intestinal wall into the blood vessels and from there to the pulmonary arteries and the right heart. There, they mature into adult worms and begin to lay eggs. These eggs develop into larvae that enter the airways and are eventually excreted via the feces to complete the life cycle.

The distribution of Angiostrongylus vasorum is worldwide, but prevalence varies by geographic region. Humid climates where snails thrive favor the spread of the parasite. The increasing mobility of dogs also contributes to the spread of the infection.

Symptoms

Rare symptoms:

The symptoms of angiostrongylosis can vary greatly and depend on the severity of the infection and the affected dog’s response. Common symptoms include cough, shortness of breath, and general respiratory distress, as the worms affect the lungs and airways.

Additionally, infected dogs may show lethargy, weight loss, loss of appetite, and general weakness. In severe cases, heart problems, coagulation disorders, and neurological symptoms such as seizures may occur.

Another sign of infection may be an increased tendency to bleed, which can manifest as nosebleeds, bloody cough, or blood in the urine. These symptoms result from damage to blood vessels caused by the parasites.

Key symptoms: Respiratory distress + reduced exercise tolerance, combined with unexplained bleeding tendencies or alternating “bronchitis/pneumonia” episodes. Suspicion especially high in regions with many snails and frogs.

Therapy

Treatment of canine angiostrongylosis requires the administration of antiparasitic medications that are specifically effective against nematodes. Moxidectin and milbemycin are two commonly used medications that can be administered orally or by injection.

In severe cases, supportive treatment may be necessary to alleviate the symptoms. This may include the administration of oxygen, fluid therapy, and medications to stabilize heart function. Anti-inflammatory drugs can also be used to reduce the inflammatory responses in the lungs.

It is important to carry out the treatment under veterinary supervision and to monitor the dog carefully during and after the treatment to ensure that it recovers fully.

Prognosis and follow-up care

The prognosis for dogs with angiostrongylosis depends on several factors, including the dog’s health status, the severity of the infection, and the speed with which treatment is initiated. Generally, dogs that are diagnosed and treated early have a good prognosis.

However, if left untreated, the infection can cause serious complications and, in the worst case, lead to death. Timely diagnosis and treatment are crucial to increase the chances of complete recovery.

After treatment, it is important to monitor the dog regularly for relapses or reinfection, as there is a risk of reinfection, especially in areas with high parasite prevalence.

Prevention

Prevention of canine angiostrongylosis focuses on avoiding contact with the parasite’s intermediate hosts. Dogs should be prevented from eating snails or slugs, and care should be taken to keep them in clean, well-maintained environments.

Regular deworming with appropriate medications can help minimize the risk of infection. It is advisable to consult a veterinarian to create a suitable deworming plan tailored to the dog’s specific needs and exposure risk.

In areas with known parasite prevalence, the use of antiparasitics that specifically target Angiostrongylus vasorum may also be considered for prophylaxis. However, these should only be used after consultation with a veterinarian to avoid overmedication.

Outlook on current research

Canine angiostrongylosis, an infection with the lungworm Angiostrongylus vasorum, is an increasingly significant problem in veterinary medicine, particularly in Europe. In recent years, research has begun to focus more intensively on this disease to improve diagnosis, treatment, and prevention. One of the most important research areas is the study of the parasite’s distribution patterns. In Europe, it has been shown that the distribution area of Angiostrongylus vasorum is expanding, partly due to climate change and the behavior of intermediate hosts such as snails and frogs. Research is investigating how these environmental factors influence prevalence and spread.

Another key focus of research is the development of new diagnostic methods. Currently, serological tests that detect antibody or antigen of the parasite in the blood are considered promising tools. These tests can enable early diagnosis before clinical Symptoms: appear. Studies are examining the sensitivity and specificity of these tests to improve their reliability. In parallel, research is also being conducted into molecular diagnostic methods based on PCR technology to detect the parasite’s genetic material directly.

Treatment of canine angiostrongylosis typically involves antiparasitics that kill the worm. Research focuses on the efficacy and safety of various active ingredients, particularly because some dogs may experience side effects after treatment. Alternative treatment strategies are also being investigated to avoid resistance and minimize side effects. This includes research into combination therapies or new drug classes.

Prevention of infection is also an important research topic. Scientists are working on developing vaccines that could protect dogs from infection. Although there is currently no approved vaccine against Angiostrongylus vasorum, initial studies show promising results in generating an immune response in dogs. In parallel, research is also being conducted on biological control of snail populations to reduce parasite transmission.

Another aspect of research is the investigation of pathogenesis, the developmental mechanisms of the disease in the dog’s body. Researchers are trying to understand how the parasite influences the dog’s immune system and what factors lead to different disease courses. These insights could help improve the prognosis for affected dogs and develop more targeted therapies.

Additionally, the role of co-infections is being investigated, as dogs with angiostrongylosis often also have other parasitic or bacterial infections. The interaction between different pathogens and their effects on the dog’s immune system are the subject of current studies. The goal is to develop more comprehensive treatment approaches that address all aspects of the infection.

Research work is supported by the use of modern technologies such as genome sequencing and bioinformatics, which enable a better understanding of the parasite’s genetic structure. This allows new target structures for therapeutic approaches to be identified. International collaboration between research institutions also contributes to the rapid advancement of knowledge in this field.

Overall, current research shows that canine angiostrongylosis is a complex and multifaceted problem that requires a multidisciplinary approach. However, advances in diagnosis, treatment, and prevention give reason to hope that control of this disease can be made more effective in the near future.

Frequently Asked Questions (FAQs)

1. What is canine angiostrongylosis?
Canine angiostrongylosis is a parasitic infection in dogs caused by the lungworm Angiostrongylus vasorum. The parasite affects the pulmonary arteries and the heart, which can lead to various health problems. -
2. How do dogs become infected with Angiostrongylus vasorum?
Dogs become infected by eating infected intermediate hosts, usually snails or frogs. These intermediate hosts pick up the parasite’s larvae from the environment, and the dog becomes infected when it eats these animals. -
3. What Symptoms: do dogs with canine angiostrongylosis show?
Symptoms can vary and include Cough, shortness of breath, Weight loss, Lethargy, Bleeding, and in severe cases, heart problems. Sometimes dogs also show neurological symptoms or Behavioral changes. -
4. How is canine angiostrongylosis diagnosed?
Diagnosis is made using a combination of clinical symptoms, blood tests that detect the parasite’s antibody or antigens, and imaging such as X-rays or ultrasound examinations of the chest. -
5. Can canine angiostrongylosis be treated?
Yes, the infection can be treated with specific antiparasitics. Treatment should be started as early as possible to avoid complications. In severe cases, intensive medical care may be required. -
6. How can I protect my dog from canine angiostrongylosis?
To reduce the risk of infection, dogs should be prevented from eating snails and frogs. There are also prevention programs based on regular deworming that your veterinarian can recommend. -
7. Is canine angiostrongylosis transmissible to humans?
No, Angiostrongylus vasorum is specific to dogs and other canids. Humans cannot become infected with this parasite. -
8. Which dogs are particularly at risk?
Dogs that spend a lot of time outdoors and have access to gardens or forests are at higher risk because they are more likely to come into Contact with infected intermediate hosts. Younger dogs also seem to be more susceptible. -
9. Are there regional differences in the distribution of Angiostrongylus vasorum?
Yes, prevalence can vary by region. The parasite is mainly found in Europe, parts of Africa, and South America. In Europe, it is currently spreading further, including into areas where it did not previously occur. -
10. Can my dog fully recover after an infection?
With timely and appropriate treatment, many dogs can make a full recovery, especially if the infection is detected early. In some cases, however, permanent damage or recurring symptoms may occur, especially if treatment is started late.

Literature

  • European Scientific Counsel Companion Animal Parasites. (2025). Worm control in dogs and cats: ESCCAP guideline 1 (Version 21). ESCCAP. https://www.esccap.org/uploads/docs/biu0jhej_0778_ESCCAP_GL1__English_2025_v21_1p.pdf
  • Leal-Sousa, B., Esteves-Guimarães, J., Matos, J. I., Oliveira, P., Lobo, L., Silvestre-Ferreira, A. C., Soares, C. S., Carretón, E., Morchón, R., Fontes-Sousa, A. P., & Montoya-Alonso, J. A. (2025). Epidemiological mapping of canine angiostrongylosis in Portugal: Findings from a nationwide prevalence survey. Veterinary Sciences, 12(7), Article 647. https://doi.org/10.3390/vetsci12070647
  • Traversa, D., Colombo, M., Di Cesare, A., et al. (2025). Current enzooticity of Dirofilaria immitis and Angiostrongylus vasorum in central and southern Italy. Animals, 15(2), Article 172. https://doi.org/10.3390/ani15020172
  • Eisenhut, B., Hermosilla, C., Taubert, A., & Ruiz, A. (2025). Host-specific vascular endothelial cell responses to Angiostrongylus vasorum infection. Frontiers in Cellular and Infection Microbiology, 15, Article 1564563. https://doi.org/10.3389/fcimb.2025.1564563
  • Liu, J., Schnyder, M., Willesen, J. L., Potter, A., Chandrashekar, R., & Breitschwerdt, E. (2017). Performance of the Angio Detect™ in-clinic test kit for detection of Angiostrongylus vasorum infection in dog samples from Europe. Veterinary Parasitology: Regional Studies and Reports, 7, 45–47. https://doi.org/10.1016/j.vprsr.2016.12.007
  • Schnyder, M., Stebler, K., Naucke, T. J., Lorentz, S., Deplazes, P., & Kortbeek, L. M. (2014). Evaluation of a rapid device for serological in-clinic diagnosis of canine angiostrongylosis. Parasites & Vectors, 7, Article 72. https://doi.org/10.1186/1756-3305-7-72
  • Di Cesare, A., Traversa, D., Manzocchi, S., Meloni, S., Grillotti, E., Auriemma, E., Pampurini, F., Garofani, C., Ibba, F., Zanet, S., & Capelli, G. (2014). Canine angiostrongylosis: Recent advances in diagnosis, prevention, and treatment. Veterinary Medicine: Research and Reports, 5, 181–192. https://doi.org/10.2147/VMRR.S53641
  • Morgan, E. R., Shaw, S. E., Brennan, S. F., De Waal, T. D., Jones, B. R., & Mulcahy, G. (2005). Angiostrongylus vasorum: A real heartbreaker. Trends in Parasitology, 21(2), 49–51. https://doi.org/10.1016/j.pt.2004.11.006
  • European Scientific Counsel Companion Animal Parasites. (2025). Worm control in dogs and cats: ESCCAP guideline 1 (Version 21). ESCCAP. https://www.esccap.org/uploads/docs/biu0jhej_0778_ESCCAP_GL1__English_2025_v21_1p.pdf
  • Leal-Sousa, B., Esteves-Guimarães, J., Matos, J. I., Oliveira, P., Lobo, L., Silvestre-Ferreira, A. C., Soares, C. S., Carretón, E., Morchón, R., Fontes-Sousa, A. P., & Montoya-Alonso, J. A. (2025). Epidemiological mapping of canine angiostrongylosis in Portugal: Findings from a nationwide prevalence survey. Veterinary Sciences, 12(7), Article 647. https://doi.org/10.3390/vetsci12070647
  • Traversa, D., Colombo, M., Di Cesare, A., et al. (2025). Current enzooticity of Dirofilaria immitis and Angiostrongylus vasorum in central and southern Italy. Animals, 15(2), Article 172. https://doi.org/10.3390/ani15020172
  • Eisenhut, B., Hermosilla, C., Taubert, A., & Ruiz, A. (2025). Host-specific vascular endothelial cell responses to Angiostrongylus vasorum infection. Frontiers in Cellular and Infection Microbiology, 15, Article 1564563. https://doi.org/10.3389/fcimb.2025.1564563
  • Liu, J., Schnyder, M., Willesen, J. L., Potter, A., Chandrashekar, R., & Breitschwerdt, E. (2017). Performance of the Angio Detect™ in-clinic test kit for detection of Angiostrongylus vasorum infection in dog samples from Europe. Veterinary Parasitology: Regional Studies and Reports, 7, 45–47. https://doi.org/10.1016/j.vprsr.2016.12.007
  • Schnyder, M., Stebler, K., Naucke, T. J., Lorentz, S., Deplazes, P., & Kortbeek, L. M. (2014). Evaluation of a rapid device for serological in-clinic diagnosis of canine angiostrongylosis. Parasites & Vectors, 7, Article 72. https://doi.org/10.1186/1756-3305-7-72
  • Di Cesare, A., Traversa, D., Manzocchi, S., Meloni, S., Grillotti, E., Auriemma, E., Pampurini, F., Garofani, C., Ibba, F., Zanet, S., & Capelli, G. (2014). Canine angiostrongylosis: Recent advances in diagnosis, prevention, and treatment. Veterinary Medicine: Research and Reports, 5, 181–192. https://doi.org/10.2147/VMRR.S53641
  • Morgan, E. R., Shaw, S. E., Brennan, S. F., De Waal, T. D., Jones, B. R., & Mulcahy, G. (2005). Angiostrongylus vasorum: A real heartbreaker. Trends in Parasitology, 21(2), 49–51. https://doi.org/10.1016/j.pt.2004.11.006