The research around the public's usage of masks to prevent the spread of COVID-19 is developing quickly. In this work, we analyzed data from 50 nations to assess the long-term effectiveness of mask policies with different levels using the Poisson regression model and generalized linear mixed model. Over the long term, stricter obligatory mask regulations were linked to more stable patterns and slower increases in Covid-19 case occurrences. The mitigation of disease transmission by mask policies was shown to have substantial major impacts throughout the entire year of 2020, whereas the incidence of illness displays increasing trends over time under various policies. When compared to no mask policy deployment, mask policies might reduce incidence growth by 13.5% to 17.8%, although the incidence under every policy climbed 1.5% to 1.9% on average every ten days. The mask policy is effective in controlling illness, according to the bulk of the data shown above. This result confirms the mask policy's importance as a governing approach in the context of the worldwide pandemic.

The authors have declared no competing interest.

This study did not receive any funding

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