Mexico took swift action and has strictly followed mitigation measures to prevent the spread of coronavirus disease, COVID-19. The present study compared indicators of influenza activity in 2020 before and after public health measures were taken to reduce COVID-19 with the corresponding indicators from three preceding years and the immediate one, and the potential decrease in seasonal influenza cases. Nationwide surveillance data revealed a drastic decline in influenza diagnosis in outpatient clinics and public hospitals, positivity rates of clinical specimens, and confirmed severe cases during the following 10 weeks of 2020 as lockdown activities and control measures were established compared with the same period of 2019, suggesting that the measures taken for COVID-19 were effective in reducing the spread of other viral respiratory diseases in our country.