Toxocariasis is a parasitosis caused by the parasite Toxocara sp. , which can inhabit the small intestine of cats and dogs and reach the human body through contact with feces contaminated by feces from infected dogs and cats, which can result in abdominal pain, fever or decreased vision, for example.
People are called accidental hosts, as this parasite is usually not adapted to the human organism, only domestic animals, for example. Therefore, when people accidentally come into contact with Toxocara sp. , the larvae are able to go to various parts of the body, causing symptoms and some syndromes, such as:
- Visceral Larva migrans syndrome or visceral toxocariasis, in which the parasite migrates to the viscera, where it can reach adulthood and results in different symptoms; Larva migrans ocular syndrome or ocular toxocariasis, in which the parasite migrates to the eyeball.
Human toxocariasis is more common in children who play on the ground, on the ground or in the sand, for example, but it can also happen in adults who have had contact with the same environment. Treatment varies according to the symptoms presented, and the use of antiparasitic drugs or the use of eye drops with corticosteroids, in the case of ocular toxocariasis, for example, may be recommended.
Main symptoms
Symptoms of toxocariasis in people arise after accidental ingestion of Toxocara sp . present in sand, earth and ground, for example. The larvae present in these eggs develop in people's intestines and travel to various tissues, causing symptoms.
In the case of visceral toxocariasis, the larvae can reach the liver, heart, lungs, brain or muscles, for example, the main symptoms being:
- Fever above 38ºC; Persistent cough; Wheezing and difficulty breathing; Abdominal pain; Enlarged liver, also called hepatomegaly; Hypereosinophilia, which corresponds to an increase in the amount of eosinophils in the blood; Skin manifestations such as pruritus, eczema and vasculitis.
In the case of ocular toxocariasis, symptoms appear when the larvae reach the eyeball, with redness of the eye, pain or itching in the eye, white spots on the pupil, photophobia, blurred vision and decreased vision, for example.
In addition, the appearance of symptoms can also vary according to the amount of parasites in the person's body and immune system. Thus, when there is a suspicion of infection by toxocariasis, it is recommended to consult the general practitioner, in the case of the adult, or the pediatrician, in the case of the child, so that the diagnosis can be made and treatment started.
The diagnosis of human toxocariasis is difficult, as it is usually only confirmed after identification of the larva by means of tissue biopsy, since this parasite is not normally found in the feces. However, it is possible to detect the presence of antibodies against the parasite in the patient's bloodstream through immunological and serological tests, which can be very useful in the diagnosis.
How the treatment is done
Treatment for human toxocariasis should be guided by the general practitioner or a pediatrician, and depends on the symptoms presented by the person. In the case of visceral toxocariasis, the treatment indicated by the doctor is with antiparasitic drugs, such as Albendazole, Tiabendazole or Mebendazole twice a day for 5 days or according to the medical recommendation.
In the case of ocular toxocariasis, the result of treatment with antiparasitic drugs is still not very well proven, and it is more recommended that the ophthalmologist recommend the use of eye drops with corticosteroids to treat the symptoms and prevent the progression of the disease leading to the development of permanent lesions in the eye. eye.
How to prevent toxocariasis
To avoid infection with Toxocara sp. , the Ministry of Health recommends that pets be periodically taken to the veterinarian to be treated against parasites and to be careful about the elimination of animal faeces and the environment they frequent.
It is recommended to wash your hands well after being in contact with domestic animals, to prevent children from playing in places where domestic animals exist and to wash the area well that the animal inhabits, at least once a week.
