Coenurosis in humans

Parasitic disease caused by tapeworm larvae

Coenurosis in humans is a rare parasitic disease caused by the larval stage of certain tapeworms belonging to the genus Taenia. The condition occurs when humans become accidental hosts of the larval form, known as coenurus, which typically infects the central nervous system of intermediate hosts such as sheep and cattle.

Etiology

Coenurosis is primarily caused by the larvae of Taenia multiceps, Taenia serialis, and Taenia brauni. These tapeworms usually complete their life cycle between canids (such as dogs and foxes) as definitive hosts and various herbivorous animals as intermediate hosts. Humans become infected through accidental ingestion of tapeworm eggs present in contaminated food, water, or soil.

Pathophysiology

Once ingested, the eggs hatch in the human intestine, releasing oncospheres that penetrate the intestinal wall and migrate through the bloodstream to various tissues. In humans, the larvae predominantly form cysts in the central nervous system, leading to neurological symptoms. The cysts, known as coenuri, can cause mass effect and inflammation, resulting in symptoms such as headaches, seizures, and neurological deficits.

Clinical Presentation

The clinical manifestations of coenurosis in humans depend on the location and size of the cysts. Common symptoms include:

• Headache
• Seizures
• Focal neurological deficits
• Increased intracranial pressure
• Visual disturbances

Diagnosis

Diagnosis of coenurosis is challenging and often requires a combination of clinical, radiological, and serological methods. Neuroimaging techniques such as MRI and CT scans are crucial for identifying cystic lesions in the brain. Serological tests can help detect specific antibodies against Taenia species.

Treatment

The treatment of coenurosis involves a combination of surgical and medical approaches. Surgical removal of the cysts is often necessary to alleviate symptoms and prevent complications. Antiparasitic drugs such as albendazole may be used to reduce the size of the cysts and prevent further growth.

Prevention

Preventive measures focus on breaking the life cycle of the tapeworms and reducing human exposure to the eggs. Key strategies include:

• Proper disposal of canine feces
• Regular deworming of dogs
• Ensuring safe and clean food and water supplies
• Educating communities about the risks of coenurosis

Epidemiology

Coenurosis is more prevalent in regions where livestock farming is common and where there is close contact between humans and dogs. It is primarily reported in parts of Africa, Asia, and South America.

Related pages

• Taenia (genus)
• Tapeworm infection
• Neurocysticercosis

A bulldog, a potential definitive host for Taenia species