Data from the Google search engine enables the assessment of Google users' interest in a specific topic. We analyzed the world trends in searches associated with the topics "antibiotics" and "probiotics" from January 2004 to June 2019, using Google Trends. We analyzed the yearly trends and seasonal variation. We performed an R-Spearman rank correlation analysis of the relative search volume (RSV) of the topics in 2015 with antibiotic consumption, health expenditure per capita, and the 2015 Human Development Index (HDI) of the country. The mean interest in the topic of antibiotics was equal to RSV = 57.5 ± 17.9, rising by 3.7 RSV/year (6.5%/year), while that of probiotics was RSV = 14.1 ± 7.9, which rose by 1.7 RSV/year (12.1%). The seasonal amplitude of antibiotics was equal to RSV = 9.8, while probiotics was RSV = 2.7. The seasonal peaks for both topics were observed in the cold months. The RSV of probiotics, but not antibiotics, was associated with antibiotic consumption (Rs = 0.35; p < 0.01), health expenditure (Rs = 0.41; p < 0.001), and HDI (Rs = 0.44; p < 0.001). Google users' interest in antibiotic- and probiotic-related information increases from year to year, and peaks in cold months. The interest in probiotic-related information might be associated with antibiotic consumption, health expenditure, and the development status of the Google users' country.
Keywords: Google Trends; Internet; antibiotics; antimicrobial resistance; probiotics.