
SAN FRANCISCO (KGO) -- More than 40,000 unionized Kaiser Permanente workers in four states walked off their jobs Tuesday, beginning a five-day strike.
In Northern California, nearly 3,000 workers are striking.
Organizers say the five-day strike across 500 medical centers and offices in California, Hawaii and Oregon is the largest in the 50-year history of the United Nurses Associations of California/Union of Health Care Professionals. The strike could grow to include 46,000 people.
PREVIOUS COVERAGE: Thousands of Kaiser Permanente workers across Bay Area and beyond set to strike Tuesday
Those on strike, including pharmacists, midwives and rehab therapists, say wages have not kept pace with inflation and there is not enough staffing to keep up with patient demand.
They are asking for a 25% wage increase over four years to make up for wages they say are at least 7% behind their peers.
Emily Hardy, a certified nurse-midwife, said, "While we really don't want to be out here, we want to be in the hospitals and clinics caring for our patients; this is the only path we see forward. Kaiser continues to dig in and not offer reasonable solutions."
"We are striking for patient care. We are striking so we can have competitive pay and retain our benefits," said Arezou Mansourian, a striking Kaiser employee.
Mansourian has been at Kaiser in Walnut Creek for 16 years. She's a senior physician assistant -- helping surgeons in the operating room, seeing her own patients, and prescribing medications.
Jeff Cathcart has been working at Kaiser San Francisco since 2005.
"I'm a nurse anesthetist. I deliver anesthesia. I'm the one that puts you to sleep," said Cathcart.
He and other striking Kaiser health workers say they want pay raises, better staffing, and improved health retirement benefits.
"It's stressful living in the Bay Area. It's an expensive place to live. We all want to be paid for what we do at the market rate," said Cathcart.
Sanne Jacobsen is a part of the bargaining team for UNAC.
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"We're all on strike to ask for a fair contract," said Jacobson.
She is also a certified registered nurse anesthetist.
"In nursing anesthesia, we've lost about a quarter of our staff over the last few years. It's making it harder and harder for us to staff the operating rooms. It's causing patients to have to wait longer times for surgeries," said Jacobson.
Kaiser Permanente says the strike is unnecessary, and it is offering to raise wages by more than 21% over four years. The company says that represented employees earn, on average, 16% more than their peers, and it would have to charge customers more to meet strikers' pay demand.
A labor union spokesperson called the offer unsatisfactory and said the union wants a 25 percent increase.
"Places like UCSF, UC General, UC Davis, are all making 25 % more than we are," said Cathcart.
"Their 21.5 percent offer is not 21.5 percent this year. It's 21. 5 percent over four years. which by then will be 60-80% behind market. It's not a benefit to us at this point. We need to catch up now, so we can hire people now, so patients can get care now," said Mansourian.
Kaiser offered this response on Tuesday, saying:
"Despite our strong economic offer, Alliance bargaining has stalled wages, and the unions have chosen to strike. While this strike is disappointing and unnecessary, we are prepared to resume negotiations after the strike to reach an agreement that balances fair pay for our employees with our obligations to deliver high-quality, affordable care."
The company said health clinics and hospitals will remain open during the strike, with some in-person appointments shifted to virtual appointments, and some elective surgeries and procedures being rescheduled.
Kaiser Permanente is one of the nation's largest not-for-profit health plans, serving 12.6 million members at 600 medical offices and 40 hospitals in largely western U.S. states. It is based in Oakland.
The strike is set to end at 7 a.m. on Sunday.
The Associated Press contributed to this article.