Visceral larva migrans
Visceral larva migrans, also known as larval granulomatosis, is a clinical syndrome produced by the extra-intestinal migration of larval nematodes and is characterized by chronic granulomatous lesions. The disease is prevalent throughout the world including India. It is caused by larvae of mainly Toxocara canis or some times T. cati. The dogs and cats are the principal reservoir hosts. The man acquires the infection by ingestion of eggs through contaminated dust. The eggs are hatched in the intestine and larvae migrate to other organs. The condition is usually seen in children of 1-5 years of age as they have a habit of dirt eating and playing at the places where soil is heavily contaminated. The liver and lungs are mainly affected; however, some times brain and eyes also get involved. The related clinical signs include pneumonia, dyspnoea, fever, coughing, loss of appetite, vomiting, convulsion, chorioretinitis, persistent eosinophilia and hepatomegaly.
The demonstration of larvae in biopsies of affected organs confirms the diagnosis. The condition can be diagnosed by seeing the elevated tortuous character of the tunnels under the skin. Complement fixation, immunofluorescence, indirect haemagglutination and ELISA are used for serodiagnosis. The public health education for personal hygiene, prophylaxis in dogs and cats and avoidance of contact with infected dogs, cats and contaminated places are the important preventive measures.