By Elisabeth Smith

SACRAMENTO (CBS13) — Sutter Health says it’s secured some, but not all of the second vaccine doses needed to fully vaccinate 90,000 seniors and healthcare workers. 

Earlier this week, the health care system had to start canceling appointments after running out of supplies. 

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On Thursday, Sutter said 30,000 shots are expected to arrive next week, with another 30,000 coming the week of March 15.  That still leaves them 30,000 doses short. 

“We understand this unfortunate situation is stressful and disruptive to many of our most vulnerable patients,” a Sutter spokesperson said.

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Because the vaccine supply is scheduled to arrive in the middle of next week, most patients will still need to reschedule. The health system anticipates it will be able to complete second doses within the CDC-recommended time frame of six weeks.

How long can you wait to get your second dose?

According to the FDA authorizations, the second dose of the Pfizer shot should be given three weeks after the first. The two doses of the Moderna vaccine should be given one month apart.

However, the CDC says, if unavoidable, the second dose of either vaccine can be administered up to six weeks — or 42 days — after the first.

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Beyond that, there is simply not enough data to know if the vaccine will be effective.