Epidemiologic approach to human toxocariasis in western France

Abstract

Toxocara canis is a common parasite in puppies. The danger to human health has not been properly established. We estimated the current incidence of this pathogen in two western districts of France, Loire-Atlantique and Maine et Loire. Blood samples from 1836 eosino-philic patients were collected and tested by an enzyme-linked immunosorbent assay (ELISA) excretory-secretory Toxocara antigen test. We obtained positive results in 22% of the cases and highly positive results in 7%. The ELISA data seemed to be age-dependent, with older patients having more positive results (P < 0.0001). The interlaboratory distribution of positive test results was statistically significantly different (P < 0.0001), suggesting regional sources. The main clinical expressions of toxocariasis were: asthenia, gastric pain, and pulmonary disease. Individual and collective surveys of this zoonotic disease need to be carried out.

Human toxocarosis. Its seroprevalence in the City of La Plata

“…In this work, using ELISA test as a diagnostic technique, a high percentage of seroprevalence (39%) was observed. This value exceeds the percentage found in France by Gueglio et al (1994) (22%). In our study the ELISA test was not made after absorption of serun samples with extracts of Ascaris suum, likely is routinely made in Brasil, what might have avoided confusing serodiagnostics, probably reducing the percentage of seropositives (Nunes et al 1997).…”

“…The sera were not absorbed with Ag de Ascaris suum (Nunes et al 1997). Serologic results were grouped according to a simple scale: 0 (negative), 1 (positive), 2 (highly positive), following a similar criterium as Gueglio et al (1994).…”

“…Some nematode parasites of animals can infect noncompatible hosts such as humans (Agudelo et al 1990, Bouchard et al 1994, Buijs et al 1994, Gueglio et al 1994) and remain in their organisms as migrating larvae arrested in their development but metabolically active (Pezzani et al 1993), eliciting mechanical damages that are exacerbated by the host's immune response (Agudelo et al 1990, Hirata et al 1990). …”

“…Species of Toxocara (parasites of dogs, cats and cattle) and Baylisascaris (very frequent ascarid in procionids), determine visceral larvae migrans (VLM) in paratenic hosts including man (Kazacos & Boyce 1990, Glickman & Magnaval 1993,Pezzani et al 1993, Gueglio et al 1994, Papini & Casarosa 1994.…”

“…It is the primary cause of VLM in humans (Sánchez et al 1994). Toxocarosis is a systemic larval parasitosis that may affect humans of different age or sex (Beaver 1956, Agudelo et al 1990, Gueglio et al 1994. It may appear in the following forms: (i) ocular larva migrans (OLM), always with serious lesions that can produce leukocoria, uveitis, retinal granulomas or chronic endophthalmitis, very often with a decrease of the visual acuity and strabismus (Beaver 1956, Villano et al 1992, Kujat et al 1993, Minvielle et al 1993, Sharkey & Mc Kay 1993; (ii) VLM associated with different clinical manifestations: hepatitis (Minvielle et al 1993), diffuse pulmonary involvement (Hotez 1993), severe asthma (Glickman & Magnaval 1993), severe eosinophilic pneumonia (Hirata et al 1990), cutaneous disorders (Kasacos & Boyce 1990, España et al 1993), myocardial (Kujat et al 1993) and gastroenteric affections (Jansen et al 1993) as well as those of the central nervous system (Beaver 1956, Khalil et al 1971, Woodruff 1975, Sellal et al 1992, Glickman & Magnaval 1993, Stenfancikova et al 1993, Kumar & Kimm 1994 usually accompanied by persistent eosinophilic increase ranging from moderate to severe; (iii) covert toxocarosis with nonspecific symptomatology: hepatomegaly, abdominal pain, sleep disturbances, headache (Agudelo et al 1990) and associated with normal or slightly increased eosinophilia.…”