Toxocariasis and childhood asthma: A case-control study

Area of Science:

• Pediatric Allergy and Immunology
• Infectious Diseases Epidemiology
• Environmental Health

Background:

• Toxocara infection is a common helminthic zoonosis with potential immunomodulatory effects.
• Asthma is a prevalent chronic respiratory disease in children, with multifactorial etiology.
• The potential role of parasitic infections, including Toxocara, in the development or exacerbation of asthma remains an area of investigation.

Purpose of the Study:

• To investigate the association between seropositivity to anti-Toxocara IgG antibodies and the risk of asthma in children.
• To identify other risk factors associated with childhood asthma in the studied population.

Main Methods:

• A case-control study was conducted with 208 children (156 cases with asthma, 52 controls without asthma) in South Brazil.
• Participants were matched by age, and data were collected via interviews and serological testing for anti-Toxocara IgG using ELISA.
• Statistical analysis included calculating odds ratios (OR) with 95% confidence intervals (CI) to assess associations.

Main Results:

• The seroprevalence of anti-Toxocara IgG was 12.8% in children with asthma and 7.7% in controls.
• No statistically significant association was found between anti-Toxocara IgG seropositivity and asthma risk (adjusted OR: 1.89, p=0.33).
• Independent risk factors for asthma included low household income, low paternal education, allergic rhinitis, family history of asthma/rhinitis, and cat contact.

Conclusions:

• This study did not establish a statistically significant link between Toxocara infection and childhood asthma.
• Low socioeconomic status, family history of allergic diseases, and environmental exposures like cat contact are significant factors associated with childhood asthma.