This study was conducted in Salvador, a city located in the northeastern coastal region of Brazil with a population of over 2.8 million and with a high reported prevalence of asthma in previous surveys [19]. To study the potential role of helminth infections in the high prevalence of allergy and asthma, we explored the effects of single or multiple helminth co-infections with A. lumbricoides, T. trichiura and Toxocara spp., on the occurrence of several allergy-associated outcomes.
on the risk of asthma.