Anisakiasis
Disease Details
Family Health Simplified
- Description
- Anisakiasis is a parasitic infection caused by the ingestion of larvae from the Anisakis genus, typically found in raw or undercooked seafood.
- Type
- Anisakiasis is a parasitic infection caused by nematodes (worms) from the Anisakidae family. It is not genetically transmitted; it is acquired through the ingestion of raw or undercooked fish or seafood contaminated with Anisakis larvae.
- Signs And Symptoms
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Signs and symptoms of anisakiasis can vary but often include:
- Severe abdominal pain
- Nausea and vomiting
- Diarrhea
- Abdominal distention
- Mild fever
- Blood and mucus in stool
- Allergic reactions (e.g., rash, itching, anaphylaxis in severe cases)
These symptoms generally appear within hours after consuming infected raw or undercooked fish. - Prognosis
- Anisakiasis typically has a good prognosis when promptly diagnosed and treated. The condition involves the parasitic infection of the gastrointestinal tract by Anisakis larvae, commonly contracted through the consumption of raw or undercooked fish. If the parasites are endoscopically removed, symptoms usually resolve quickly. Without intervention, the infection can cause complications such as gastric or intestinal ulcers, bowel obstruction, or peritonitis. Advanced cases may require surgical intervention. Generally, with early medical attention, the long-term outlook for anisakiasis is favorable.
- Onset
- Anisakiasis onset typically occurs within hours after ingestion of raw or undercooked fish or squid containing Anisakis larvae. Symptoms may include severe abdominal pain, nausea, vomiting, and occasionally an allergic reaction.
- Prevalence
- Anisakiasis is relatively rare but more prevalent in areas where raw or undercooked fish is commonly consumed, such as Japan, Scandinavia, the Netherlands, and South America. The incidence in these areas can vary, with Japan reporting hundreds of cases annually. In other parts of the world, including North America and Europe, cases are sporadic and less common.
- Epidemiology
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Anisakiasis is a parasitic disease caused by the ingestion of raw or undercooked fish or squid containing larvae of Anisakis species.
**Epidemiology:**
- **Geographical Distribution:** Most common in countries where raw or undercooked fish is a dietary staple, particularly in Japan, South Korea, and some European countries.
- **Incidence:** Difficult to determine precisely due to underreporting, but considered relatively rare in North America and Europe compared to East Asia.
- **Risk Factors:** Consumption of raw or undercooked marine fish and squid, including sushi, sashimi, ceviche, and pickled herring.
- **Affected Populations:** Higher incidence in populations with dietary habits involving raw fish, with occasional cases in travelers or residents of non-endemic regions following ingestion of contaminated seafood.
Understanding these factors can help in the prevention and management of anisakiasis through dietary changes, proper cooking, and awareness. - Intractability
- Anisakiasis, caused by parasitic nematodes of the Anisakidae family, is not generally considered intractable. It often results from consuming raw or undercooked seafood. Symptoms typically include abdominal pain, nausea, vomiting, and can sometimes result in allergic reactions. Endoscopic removal of the larvae from the gastrointestinal tract is the most effective treatment, leading to quick symptom relief. Prevention involves properly cooking or freezing seafood to kill the larvae. Therefore, with prompt medical intervention and preventive measures, anisakiasis is manageable and not considered intractable.
- Disease Severity
- Anisakiasis is typically moderate to severe. The condition arises when people ingest raw or undercooked fish or squid contaminated with Anisakis larvae. Symptoms can include severe abdominal pain, nausea, vomiting, and complications such as intestinal obstruction or perforation if not treated promptly.
- Healthcare Professionals
- Disease Ontology ID - DOID:7033
- Pathophysiology
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Pathophysiology:
Anisakiasis is caused by the ingestion of larvae of Anisakis species, which are parasitic nematodes (roundworms). These larvae are commonly found in raw or undercooked marine fish and squid. When ingested, the larvae can penetrate the gastrointestinal mucosa, leading to symptoms such as abdominal pain, nausea, vomiting, and, in severe cases, gastroenteritis, allergic reactions, or small bowel obstruction. The body's immune response causes localized inflammation and tissue damage at the site of larval penetration. The larvae may eventually die and are expelled from the body, but this can take weeks to months, during which time symptoms persist. - Carrier Status
- Anisakiasis is caused by the ingestion of raw or undercooked fish or squid infected with Anisakis larvae. There is no carrier status associated with the disease because it results from direct infection by the parasite.
- Mechanism
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Anisakiasis is a parasitic infection caused by the ingestion of larvae from anisakid nematodes, commonly found in raw or undercooked seafood. The larvae can invade the gastrointestinal tract, leading to various symptoms.
**Mechanism:**
After ingestion, the Anisakis larvae penetrate the gastrointestinal mucosa. This causes an acute inflammatory response, including the infiltration of eosinophils and other immune cells, which leads to tissue damage and symptoms such as acute abdominal pain, nausea, vomiting, and diarrhea. If the larvae penetrate deeper tissues, they can cause granulomas and more severe complications like bowel perforation or peritonitis.
**Molecular Mechanisms:**
The immune response to Anisakis larvae involves both innate and adaptive immunity. Key molecules and processes include:
1. **Innate Immune Response:** The penetration of larvae triggers an immediate response from the immune system. Pattern recognition receptors (PRRs) on epithelial cells and immune cells recognize pathogen-associated molecular patterns (PAMPs) on the surface of the larvae, activating pathways that lead to inflammation.
2. **Cytokines and Chemokines:** Following the initial immune recognition, cytokines such as IL-4, IL-5, and IL-13 play critical roles in promoting eosinophil activation and recruitment. Chemokines help attract additional immune cells to the site of infection.
3. **Eosinophil Activation:** Eosinophils, a type of white blood cell, are particularly important in combating parasitic infections. They release toxic granules that can damage or kill the larvae but also contribute to tissue damage and inflammation.
4. **Antibody Production:** The adaptive immune response involves the production of specific IgE antibodies against Anisakis antigens. This can lead to mast cell activation and further inflammatory responses, sometimes contributing to allergic reactions.
Additionally, research has identified specific allergens from Anisakis (e.g., Ani s 1, Ani s 2, etc.), which can trigger allergic reactions in sensitized individuals. Identifying these allergenic proteins has been crucial for understanding allergic manifestations and developing diagnostic tests for anisakiasis. - Treatment
- For the worm, humans are a dead-end host. Anisakis and Pseudoterranova larvae cannot survive in humans, and eventually die. In some cases, the infection resolves with only symptomatic treatment. In other cases, however, infection can lead to small bowel obstruction, which may require surgery, although treatment with albendazole alone (avoiding surgery) has been reported to be successful. Intestinal perforation (an emergency) is a possible complication.
- Compassionate Use Treatment
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Anisakiasis is primarily treated through endoscopic removal of the larvae, as there are currently no established systemic drug treatments specifically approved for this condition. For compassionate use or off-label treatments:
- **Albendazole**: This antiparasitic drug has been used off-label to manage anisakiasis, particularly to alleviate symptoms in cases where endoscopic removal is not feasible.
- **Corticosteroids**: These may be administered off-label to help reduce inflammation and allergic reactions caused by the parasite.
Experimental treatments are limited, and management often focuses on symptomatic relief and addressing any resulting complications. - Lifestyle Recommendations
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For anisakiasis, here are some lifestyle recommendations:
1. **Avoid raw or undercooked fish and squid**: Anisakis larvae are typically found in these types of seafood. Ensure your seafood is fully cooked to an internal temperature of 145°F (63°C).
2. **Freeze fish properly**: If you plan on consuming raw fish, freeze it at -4°F (-20°C) or below for at least 7 days, or freeze it at -31°F (-35°C) or below until solid and store at -31°F (-35°C) or below for 15 hours.
3. **Purchase from reputable sources**: Obtain seafood from reliable suppliers who follow proper freezing and handling procedures.
4. **Inspect fish**: Carefully examine fish for visible larvae before preparation.
5. **Educate yourself**: Be aware of the types of fish prone to Anisakis infection, such as salmon, herring, cod, and mackerel. Take extra precautions with these species.
6. **Practice good kitchen hygiene**: Use separate utensils and cutting boards for raw and cooked seafood to prevent cross-contamination.
Following these recommendations can significantly reduce the risk of developing anisakiasis. - Medication
- There is no specific medication for anisakiasis. Treatment primarily involves the physical removal of the larvae through endoscopy or surgery. Pain relievers and anti-inflammatory drugs may also be used to manage symptoms. Prevention is key by ensuring that fish is properly cooked or frozen to kill any parasites.
- Repurposable Drugs
- Currently, there are no well-established repurposable drugs for the treatment of anisakiasis. The primary treatment for this parasitic infection, caused by consuming raw or undercooked fish contaminated with Anisakis larvae, is the physical removal of larvae via endoscopy or surgery. Symptomatic treatment may include pain relief and antiallergic medications to address allergic reactions.
- Metabolites
- Anisakiasis is a parasitic infection caused by the ingestion of larvae from Anisakis nematodes, usually through consuming undercooked or raw seafood. The primary concern is the physical trauma to the intestinal lining caused by the larvae, rather than specific metabolites, which are not typically the focus of this disease. The body’s immune response to the larvae can cause symptoms such as severe abdominal pain, nausea, and vomiting.
- Nutraceuticals
- Nutraceuticals are not established as a treatment for anisakiasis. Anisakiasis is caused by the ingestion of larvae from parasites in the Anisakidae family, typically through consuming raw or undercooked fish. Treatment generally involves the physical removal of the larvae through endoscopy or surgery, and symptom management with medications. There is limited evidence on the use of nutraceuticals for this condition.
- Peptides
- Anisakiasis is a parasitic disease caused by the ingestion of larvae from certain nematodes, primarily Anisakis species, found in undercooked or raw fish. The disease rarely relates to specific peptides. Instead, it is characterized by a strong immune response where the larvae invade the gastrointestinal tract, causing symptoms such as abdominal pain, nausea, and vomiting. Current treatment does not typically involve peptides but may include endoscopic removal of the larvae and symptomatic relief for the patient.