It joins San Mateo County, which moved into the orange tier last week.
Santa Clara County Health Officer Dr. Sara Cody said the tier change reflects the county's persistence in reducing its cases and hospitalizations.
The tier change from red to orange will allow each county to increase indoor capacity from 25% to 50% for sectors such as places of worship, movie theaters and restaurants. Gyms and fitness centers will be allowed to raise capacity from 10% to 25%.
Orange is the most restrictive tier in which bars can operate under any circumstance. (A move to the looser yellow tier would allow a county to resume indoor operations at bars at 25% capacity or 100 people, whichever is fewer, according to the California Department of Public Health.)
Under the orange tier, business sectors like family entertainment centers, cardrooms, offices and wineries will be allowed to resume indoor operations after being limited to opening outdoors or being closed altogether in the red and purple tiers.
On April 1, counties in the orange tier can allow 33% capacity crowds at outdoor professional sporting events and 25% capacity or 500 people, whichever is fewer, at amusement parks.
Guests at outdoor arenas must be state residents while amusement park guests must live in the same county as the venue.
Details on which businesses can operate in the orange tier and at what capacity can be found at covid19.ca.gov/safer-economy.
Also this week, Santa Clara County entered into a "settlement in good faith" with the state that will allow the county to work directly with the state to get its supply of the vaccines, without signing an agreement with third-party administrator Blue Shield. A memorandum with Blue Shield would have prohibited the county from transferring vaccine doses to its health partners, hampering efforts to focus on communities most impacted by the virus.
"The most important thing is we can subgrant the vaccines to community clinics that are part of our network," county Board of Supervisors President Cindy Chavez said Wednesday.
The county also won't be required to use the state's system for residents to sign up for their vaccine appointments until it becomes more functional, she said.
The trend in overall vaccinations by the county health system and first and second doses decreased this week due to continued issues with allocations by the state, county leaders told the Board of Supervisors Tuesday. The seven-day average for county-administered first doses of the Pfizer-BioNTech and Moderna vaccines has plummeted to 911 compared to more than 5,000 doses two weeks ago. The number of second doses remains relatively flat. The seven-day average total for all doses, including the single-dose Johnson & Johnson vaccine, has dropped from a high of about 8,000 two weeks ago to 5,118, according to county data.
While the county's allocations have slid, doses allocated to Kaiser Permanente have finally risen. The county recently had to transfer back to Kaiser 22,000 appointments initially made at county sites, so that patients would receive their shots at Kaiser.
Meanwhile, county health leaders said they are seeing a flattening of the trajectory of COVID-19 cases rather than a continued decline.
Cody told county supervisors on Tuesday she is hopeful that, if there is another surge, it might not be as severe because more people have been vaccinated, but she cautioned that there are many unknown variables, including the rise of variants of the deadly virus that are known to make people more sick.
Cody said that the region is "not out of the woods" yet and should continue to take precautions that public health leaders have recommended throughout the pandemic.
The county has now vaccinated 69.1% of residents ages 75 and older with at least one dose and 66.2% of residents ages 65 and older with at least one dose, county COVID-19 testing and vaccine officer Dr. Marty Fenstersheib said at the board meeting.
When factoring in the entire population of residents ages 16 and older, overall, 28.2% have received at least one dose. Broken down by race, 22.8% of African Americans, 28.4% of Asians, 15.9% of Latinos and 30.4% of whites have been either fully or partially vaccinated. Fenstersheib said.