At the time, Gov. Tom Wolf said mask-wearing could be a requirement in Pennsylvania until a coronavirus vaccine is available.
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Which will be never, as Covid19 is a corona class virus like AIDS, SARS, or the common cold , for none of which a vaccine exits.
Correction, for which none of those diseases does an effective vaccine exist. Also worth mentioning is HIV, in which the host of the infection is the exact mechanism needed to make the vaccine work and initiate the response.