SAN FRANCISCO (CBS SF) – As COVID-19 vaccine availability continues to expand, Rite-Aid pharmacies announced that all of its locations in the Bay Area and across the country are offering the shots.

“Beginning today doses are being administered by the chain’s certified immunizing pharmacists across more than 2,500 locations in 17 states, including California,” a company spokesperson said Friday.

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All three authorized vaccines from Pfizer, Moderna and Johnson & Johnson are being offered. Appointments for adults 18 and older can be scheduled on the pharmacy’s website.

Meanwhile 16 and 17-year-olds, who are only authorized to receive the Pfizer vaccine, must call a location that is offering the shot. A list of pharmacies offering the Pfizer shot can be found here.

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The pharmacy chain said while scheduling an appointment is recommended, a limited number of walk-in appointments will be available to increase access, particularly for those without internet access.

Following a rollout that has been slow at times, vaccine availability in the Bay Area has rapidly expanded in the latter half of April, with a growing number of health care providers offering walk-in sites. At least two Bay Area counties have administered one million shots, Santa Clara and Contra Costa.

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As of Friday, more than 99 million Americans have been fully vaccinated and 55% of adults have received at least one dose, according to the Centers for Disease Control and Prevention.