Seeking an "equity" approach to allocating COVID-19 vaccine doses across the state, California health officials announced Thursday that 40% of vaccine doses will be reserved for low-income and minority communities that have been disproportionately affected by the pandemic.

The preference will roughly double the allotment to ZIP codes and census tracts with poor health outcomes and higher rates of COVID-19 cases and deaths. The state has administered 10 million doses of the vaccine to date, but just over one-third of those shots have gone to residents in wealthier, healthier communities.

Health officials say the new focus will be essential for reopening the economy and recovering from the pandemic, and its success will directly affect when counties will be able to enter the less-restrictive red, orange and yellow tiers.

"This is a key strategy to keep the pressure off of our health care delivery system," said Dr. Mark Ghaly, California's secretary of the Health and Human Services Agency. "As we achieve higher levels of vaccines in the hardest hit communities, we feel more and more activities across the state can occur."

The initial goal is to vaccine 2 million California residents who are in the lowest quartile of the state's so-called Healthy Places Index (HPI), which maps communities based on everything from chronic diseases and air quality to income and education level. In Santa Clara County, the lowest quartile includes a dozen census tracts located in San Jose. There are no census tracts in San Mateo County in the lowest quartile.

Ghaly said the plan must go beyond an increased allotment, and that the state will lean on community clinics, public hospital systems and trusted pharmacies in the communities to act as liaisons. It also means reserving appointments for residents who are "severely impacted" by the pandemic, and a boost in funding for safety net providers responsible for doing the outreach.

With an expected increase in supply and a third vaccine by Johnson & Johnson now approved, Ghaly said the shift in availability shouldn't reduce the number of shots available to communities that don't fall under the lowest HPI quartile. It will slow the increase in available shots, however. The new priorities will not affect plans to extend vaccine eligibility to people with disabilities and high-risk conditions on March 15.

Once the state hits its 2 million vaccine benchmark, the plan is to lower the threshold for counties to go from the most restrictive purple tier to the red tier. Counties will only need to reduce daily cases to 10 per 100,000 residents — rather than seven — in order to be reclassified.

Ghaly called the change a "small but meaningful step" that adjusts to a new normal, following a dark stage of the pandemic in which case counts, hospitalizations and deaths surged over the winter months. But he hesitated to say the state is rushing to reopen, and said that California will maintain some of the strongest public health restrictions in the country.

"We will keep our foot on the brake, not on the gas," he said.

Find comprehensive coverage on the Midpeninsula's response to the new coronavirus by Palo Alto Online, the Mountain View Voice and the Almanac here.