Immigrants and seasonal respiratory allergies: an observational look at internet search flows – the situation in Italy

Background: The prevalence of respiratory allergic diseases is increasing worldwide. In Europe, migration is a significant phenomenon, but little is known about their epidemiology in immigrants, normally coming from low-income countries and showing lower prevalence than natives. Over time, seasonal respiratory allergies increase with different patterns among first- and second-generation immigrants. Airborne pollen can be an indicator of exposure to airborne allergens, but traditional monitoring using Hirst-type samplers requires considerable resources, time consuming and delay of data. As a complementary and low-cost alternative, researchers are increasingly analysing internet search behaviour to monitor allergy-related phenomena. This study evaluated Google Trends (GTs) as an indicator for the epidemiological surveillance of seasonal pollen-related allergies among different immigrant populations living in Italy, considering that immigrants represent 8.8% of the Italian population. Methods: By GTs we analysed flow, searched for terms related to allergy and performed in different languages from 2009 to 2019. The search terms such as “allergy”, “rhinitis”, “asthma”, “antihistamine” and “pollen” were analysed. Descriptive statistics and correlations were performed. Results: Cross-language GTs analyses showed distinct seasonal peaks mostly in April and May but also in June, August and October with correlations between some languages. Discussion: Language-specific search suggests varying awareness, health-seeking behaviour and exposure patterns among immigrant communities.