Year-Long Rhinovirus Infection is Influenced by Atmospheric Conditions, Outdoor Air Virus Presence, and Immune System-Related Genetic Polymorphisms.

Rhinovirus is a common picornavirus with over 150 serotypes and three species, which is responsible for half of the human common cold cases. In people with chronic respiratory conditions and elders, it may also cause life-threatening diseases. Transmission routes are not definitively established but may involve direct human-to-human and indirect transmission (surfaces and aerosols based). In the present study, year-long presence of virus was tested by qPCR in the nostrils of young healthy volunteers and indoor and outdoor air samples. Results were correlated to atmospheric conditions (meteorological and air quality parameters) and voluntaries immune system-related genetic polymorphisms (TOLLIP rs5743899, IL6 rs1800795, IL1B rs16944, TNFA rs1800629) typed by PCR-RFLP. Nasal samples showed increased frequency and viral titers of Rhinovirus in spring and autumn. No indoor air samples tested positive for Rhinovirus, whereas outdoor air samples tested positive in late autumn. Sun radiation, atmospheric SO2, and benzene levels correlated with nostrils Rhinovirus detection. Both IL6 and TOLLIP polymorphisms but not TNFA or IL1B influenced Rhinovirus detection in the nostrils of voluntaries. Taken together, the results indicate that Rhinovirus circulation is determined by environmental conditions (weather, air-borne virus, and air pollution) and genetically encoded individual variation in immunity.