BACKGROUND: Scientific evidence suggest that hand hygiene as one of the most effective measures to control infection. To promote good hand hygiene practices, the World Health Organization introduced May 5 as World Hand Hygiene Day (WHHD), and international stakeholders established Global Handwashing Day (GHD) on October 15. However, its contributions to raising public awareness of hand hygiene is unclear. METHODS: This study evaluates the impact of the WHHD and GHD on the public awareness of hand hygiene in Japan, the United Kingdom, the United States, and worldwide from 2016 to 2020, using the relative search volume of "Hand hygiene" in Google Trends as a surrogate. To identify a statistically significant timepoint of a trend change, we performed Joinpoint regression analysis. RESULTS: Upticks of the relative search volumes as well as joinpoints were noted worldwide around the WHHD and GHD from 2016 to 2019, but no joinpoints were identified around the WHHD and GHD in 2020. No such changes were observed in Japan, the United Kingdom, and the United States during these periods. CONCLUSIONS: While the WHHD was originally established to raise awareness of hand hygiene in healthcare facilities, our result suggests that the WHHD and GHD may not have effectively disseminated the importance of hand hygiene to the general public at a country level. Additional policy measures to advocate hand hygiene to the public are necessary to communicate its benefits.