McDonald'sThe company confirmed on Monday that customers and employees in all restaurants in areas of high or severe transmission in the United States are required to wear masks again, regardless of whether they have been vaccinated or not.

Companies have adjusted their vaccination and mask programs as a result of a surge in COVID-19 cases in the US caused by a variant of the Delta virus and new guidelines from the US Centers for Disease Control and Prevention (CDC) requiring fully vaccinated individuals to still wear masks.

Last week, includingAlphabet Inc-CL CParent company Alphabet,UberAndFacebook IncBig companies say all American workers must be vaccinated to enter the office.

McDonald's Corp also said that unvaccinated employees and customers must wear masks, regardless of whether they are in areas with high spread of the virus.