Google trends identifying seasons of religious gathering: applied to investigate the correlation between crowding and flu outbreak

Abstract In medical research, mass gathering is considered as one of the intensifying factors for respiratory disease outbreaks. An annual crowding event happens during Muslims’ religious practices of Hajj in Saudi Arabia. Another smaller ritual happens all year round, known as Umrah. While Hajj season is recognized, Umrah seasonality is challenging to identify. This paper uses data from Google Trends to identify Umrah seasons for performers from the Eastern Province in Saudi Arabia. It then investigates the correlation between mass gathering events as it affects the flu spread in the Eastern Province through the use of data. Patient data from a hospital was obtained to find flu seasonality and compared to crowding seasons. Google Trend data was confirmed by a limited dataset of official Umrah data and Flu data was confirmed by official FluNet data from neighboring country, Bahrain. An Exploratory Data Analysis (EDA) approach has been followed to identify the seasonality. Cross-correlation analysis found a strong positive correlation between crowding seasons and flu outbreaks in the Eastern Province with a forward shift of flu data for three months.