Exposure to the parasitic roundworm Ascaris lumbricoides/suum could potentially cause significant reduction in lung function, finds a new study. The study conducted jointly by researchers at Universities of Norway, Denmark and Estonia found that exposure to this parasitic roundworm causes reduction in lung function, which leads to nearly five times higher odds of having asthma compared to the non-exposed. Published in the journal of Allergy and Clinical Immunology,  the new study also reports that the lung function in women was not significantly affected by the roundworm. The researchers highlighted the need for further research in this field as they fear that Ascaris infection in Europe might have overlooked the factor of asthma and respiratory health.