Google searches for the keywords of "wash hands" predict the speed of national spread of COVID-19 outbreak among 21 countries.

This study hypothesized that national population health literacy might reflect on their keywords searching. We applied Google searches for "wash hands" and "face mask" during January 19 to February 18 as a surrogate of national population health literacy among 21 countries, and examine whether google searches for "wash hands" and "face masks" would protect from increased numbers of confirmed cases of among 21 countries We found the increased google searches for "wash hands" from January 19 to February 18, 2020, correlated with a lower spreading speed of COVID-19 from February 19 to March 10, 2020 among 21 countries (Pearson's correlation coefficient of -0.70, P < 0.001). The result highlights the importance of public awareness of hand washing in preventing COVID-19 disease spreading.