SANTA ANA, Calif. (CNS) — Orange County has met the COVID-19 metrics to move to the less-restrictive orange tier under the state's blueprint for reopening the economy, but will have to wait until March 31 or April 7 to officially graduate to that level.

The latest weekly update from the state, issued on Tuesdays, shows the county's test positivity rate improved from 2.2% to 2.1%, and the adjusted case rate per 100,000 people on a seven-day average with a seven-day lag improved from 4 to 3.5 last Tuesday.

The county's Health Equity Quartile rate, which measures positivity in hotspots in disadvantaged communities, improved from 3.5% last week to 3.2%.

Because the county must remain in the red tier for three weeks and maintain the current levels for two weeks the earliest the county could move up to the orange tier would be April 7, officials say.

However, it was unclear how much credit the county has for remaining in the red tier, and it is possible the county could graduate to the orange tier March 31, Orange County CEO Frank Kim said.

County officials have sought clarification from the state Department of Public Health, Kim said.

Orange County Supervisor Lisa Bartlett said it is possible the county could move up sooner if the state relaxes its standard by meeting its goal of 4 million inoculated in its health equity category statewide.

Dr. Clayton Chau, director of the Orange County Health Care Agency and the county's chief health officer, said the state has inoculated about 2.8 million people in the health equity category. The county estimates that 90% of its seniors have been inoculated, Chau said.

Chau told the Orange County Board of Supervisors on Tuesday that there have been 1.198 million shots distributed in Orange County, which means 430,200 people have been fully inoculated. About 22,000 have received the one- dose Johnson & Johnson vaccine, he said.

About 335,000 have received at least the first of two doses of the Pfizer or Moderna vaccines, Chau said. Studies show that those vaccines are 94% successful at preventing infection with a booster shot and about 85% effective without the booster shot,  Chau said.

With a booster shot Pfizer or Moderna would provide protection against infection for about 18 months, Chau said.

It takes two weeks after receiving a shot for the recipient to be protected, Chau said.

County officials will offer more evening hours at the Santa Ana College POD to accommodate food industry workers who have less regular hours, Chau said.

Bartlett said the vaccines are a likely reason coronavirus cases and hospitalizations are falling.

"Every county is improving and I think it has to do with the number of people vaccinated and we're building herd immunity," Bartlett said. "We're doing vastly better this month than we did last month."

Chau agreed.

"I think that we've seen a dramatic drop in hospitalizations and the case rates and positivity rates because of the vaccines are now here for three months now," Chau said.

Chau acknowledged that recent variants are "more contagious," but that he was "optimistic" that the vaccines will pave a path out of the pandemic.

"But I want the  community to understand we need to be very cautions," Chau said.

The county has about a million residents registered with the Othena app and website that helps book appointments for vaccinations.

The county board approved a memorandum of understanding with Blue Shield on vaccine distribution instead of the state because it will be easier to continue using the Othena app with Blue Shield than the state.

The county can move the Othena information to the state's MyTurn app, but it would require the registrants to register again, Bartlett said.

The county approved 119 new COVID-19 cases, upping the cumulative to 249,760.

Hospitalizations decreased from 195 on Monday to 188, as the number of COVID-19 patients in intensive care dropped from 50 to 40, according to the Orange County Health Care Agency.

The county also logged 27 more COVID-19 fatalities, upping the death toll to 4,635.

The death toll for March increased to 64 and 504 for February. In January, the deadliest month of the pandemic, there have been 1,444 fatalities reported. In December, the second deadliest month, there were 916 deaths reported.

The county had 36% of its ICU beds available Tuesday and 70% of its ventilators.

The OCHCA also reported 7,150 COVID-19 tests Tuesday, raising the cumulative total to 3,261,466.

"The numbers look great," said Andrew Noymer, a UC Irvine professor of population health and disease prevention, on Monday.

"People keep asking me about variants and shouldn't we be looking out for variants," Noymer said. "They're worrisome and will happen sooner or later, but maybe not until next winter when most people are vaccinated and this is a big nothing ... The numbers now look really, really good in Orange County and we should be happy about it."

Noymer was also encouraged by the reports that a fourth vaccine may be authorized soon by the Food and Drug Administration.

"AstraZeneca being authorized is good -- I'm all for it," he said.

As for reports of blood clotting in some recipients in Europe, Noymer said it was rare. Officials are reporting it is not connected to the vaccine but is a common symptom among the elderly.

"The blood-clotting issue is a mountain out of a molehill," Noymer said. "We're talking about very rare cases here so I'm not super worried."

There is only one skilled nursing facility in the county that has an outbreak, defined as two or more cases within the past two weeks. There are only two inmates in the county jails who are infected.

Orange County is doing 277.5 tests per 100,000 people on a seven-day average with a seven-day lag. Its testing average mirrors the state average, Kim said.