Toxocariasis is a tropical disease caused by the roundworm, toxocara. It is transmitted to humans with the accidental consumption of soil contaminated with the eggs of the parasite excreted in cat or dog feces [1]. The eggs release larvae which puncture the intestinal wall and migrate through the circulatory system to various organs of the human body (brain, eyes, heart, liver, lungs and muscle) where they cause inflammation leading to symptoms of toxocariasis.

The clinical presentation of toxocariasis depends upon the organ system involved and can be classified as:

• Visceral larva migrans (VLM) - involving all major organs
• Ocular larva migrans (OLM) - involving the eyes and the optic nerve
• A covert form which is difficult to diagnose.

VLM affects mainly children under the age of five [2] who present with fever, pain in abdomen, hepatosplenomegaly, eosinophilia, bronchospasm, seizures, neuropsychiatric or cognitive symptoms or encephalopathy depending on the organ system involved.

OLM, on the other hand, affects children in the five to ten year age group and is associated with unilateral visual impairment and, strabismus [3]. In severe cases of OLM, there may be retinal invasion with granuloma formation in the posterior pole, heteropia and macular detachment [4]. There may also be endophthalmitis, papillitis followed secondarily by glaucoma and blindness.

The covert form of toxocariasis can present insidiously with headache, coughing, abdominal pain and hepatosplenomegaly or symptoms resembling asthma e.g. dyspnea, wheezing and coughing [1] [5].

The diagnosis of the disease is based mainly on the history and symptoms of multi-organ or ocular involvement. Serological testing and biopsy or autopsy specimens showing larvae help to confirm the diagnosis.

Toxocariasis should be suspected in a child with a history of pica, contact with dogs or cats, clinical signs of unexplained febrile illness with hepatosplenomegaly, eosinophilia or ocular symptoms. A complete blood count will reveal eosinophilia, although it may be absent in some cases of OLM and covert toxocariasis.

Confirmation of the diagnosis relies on the laboratory demonstration of specific anti-toxocara antibodies in either the serum or aqueous or vitreous fluid of the infected individual. The enzyme-linked immunosorbent assay (ELISA) test which uses antigens from the second stage larva is the best indirect test for the diagnosis of toxocariasis. Although histopathology of tissue samples with the identification of larvae or the detection of larval DNA in tissues is definitive, it is difficult to obtain such infected tissue samples [6] [7].

The diagnosis of OLM is based on clinical criteria and ophthalmic examination as immunodiagnostic tests are not as reliable as for VLM [8]. Neuroimaging, especially magnetic resonance imaging (MRI) is recommended to detect granulomas in the cortical or subcortical layers of the brain in patients with neuropsychiatric symptoms. MRI findings combined with cerebrospinal detection of eosinophil is indicative of toxocara infection.

Treatment for toxocariasis depends on the severity and form of the disease. Mild cases may resolve without intervention. In more severe cases, antiparasitic medications like albendazole or mebendazole are prescribed to kill the larvae. Corticosteroids may be used to reduce inflammation, particularly in cases involving the eyes or severe organ involvement. Regular follow-up is essential to monitor the patient's response to treatment.

The prognosis for toxocariasis is generally good, especially with early diagnosis and appropriate treatment. Most patients recover fully, although some may experience lingering symptoms or complications, particularly if the eyes are affected. In rare cases, severe organ damage can occur, leading to long-term health issues. Early intervention and treatment significantly improve outcomes.

Toxocariasis is caused by the larvae of Toxocara canis and Toxocara cati. These parasites are primarily found in the intestines of dogs and cats. Eggs are shed in the feces of infected animals, contaminating the environment. Humans become infected by ingesting these eggs, which hatch into larvae and migrate through the body, causing disease.

Toxocariasis is a global health concern, with higher prevalence in areas where dogs and cats are common and sanitation is poor. Children are more frequently affected due to their play habits and close contact with soil. The disease is more prevalent in rural and urban areas with high populations of stray animals. In the United States, it is estimated that several million people have been exposed to Toxocara.

Once ingested, Toxocara eggs hatch into larvae in the human intestine. These larvae penetrate the intestinal wall and enter the bloodstream, migrating to various organs such as the liver, lungs, eyes, and brain. The body's immune response to the migrating larvae causes inflammation and tissue damage, leading to the symptoms associated with toxocariasis.

Preventing toxocariasis involves reducing exposure to Toxocara eggs. This can be achieved by practicing good hygiene, such as washing hands thoroughly after handling soil or animals. Regular deworming of pets, especially dogs and cats, is crucial to reduce the shedding of eggs. Keeping play areas clean and preventing children from eating soil can also help minimize risk.

Toxocariasis is a parasitic infection caused by Toxocara larvae, primarily affecting children. It can present as visceral or ocular larva migrans, with symptoms ranging from mild to severe. Diagnosis involves clinical evaluation and laboratory tests, while treatment includes antiparasitic medications and, in some cases, corticosteroids. Prevention focuses on hygiene and pet care. With timely intervention, the prognosis is generally favorable.

Toxocariasis is an infection caused by roundworm larvae from dogs and cats. It can cause symptoms like fever, cough, and vision problems. Children are more at risk due to their play habits. The disease is diagnosed through blood tests and treated with medications. To prevent infection, practice good hygiene and ensure pets are regularly dewormed. Most people recover well with treatment.

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