According to the state, the new vaccine eligibility includes everyone aged 16 to 64 with an underlying health condition that makes them susceptible to severe illness or death from COVID-19.
Also eligible will be anyone 16 or over who suffers from a "developmental or other severe high-risk disability" that leaves the person susceptible to serious illness or death from COVID. People will also be eligible if acquiring COVID will limit the person's ability to receive necessary ongoing care or services; or if the disability would hamper the person's ability to be treated for COVID.
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The expansion means 4.4 million Californians are now added to the eligibility list.
The qualifying conditions are:
-- chronic kidney disease, stage 4 or above
-- chronic pulmonary disease
-- Down syndrome
-- weakened immune system from solid organ transplant
-- sickle cell disease
-- heart conditions
-- severe obesity
-- Type 2 diabetes mellitus
The vaccine supply, however, hasn't grown much and the state is still setting aside 40% for people in underserved communities and 10% for teachers.
"During registration people who are eligible because of a qualifying health condition or disability will be asked to verify that they have a high-risk medical condition or disability without disclosing the specific condition," said Dr. Barbara Ferrer, the Los Angeles County Public Health Director.
In addition to people with underlying health conditions, homeless people also became eligible for vaccinations starting Monday, joining newly eligible workers -- custodians/janitors, public transit workers and airport ground crew workers.
And as infections drop and vaccinations increase, Southern California counties are starting to move out of the most restrictive purple tier of the state's color-coded COVID-19 economic reopening blueprint. More than 90% of the state will be out of the most restrictive tier by Wednesday.
Los Angeles, Orange and San Bernardino counties are now in the red tier, and Ventura and Riverside will move into the red tier on Tuesday.
"Though we are taking initial steps to reopen some of the hardest-hit sectors of our economy this in no way means we can completely drop our guards," said L.A. County Supervisor Hilda Solis.
City News Service contributed to this report.