By CBSLA Staff

PASADENA (CBSLA) — In Pasadena, more than a thousand critical care workers were being vaccinated for coronavirus during a pair of drive-thru events scheduled for Tuesday and Wednesday.

But Gov. Gavin Newsom Monday said the statewide rollout has gone too slowly. He said the state has received just under 1.3 million vaccine doses, but fewer than 500,000 people have received the shots.

Dr. Oliver Brooks, who sits on the state’s vaccine committee which helps establish distribution rules, said there have been logistical challenges with the vaccine allocations.

“We are dealing with a biological product, so, for example, we have to ensure that whoever is requesting the vaccine has the proper storage,” Brooks, who is also chief medical officer of the Watts Healthcare Corporation, said. “They have to ensure they have the proper trained personnel on staff to administer the vaccine. We have ensure that they are able to document the administration of the vaccine. They have to ensure that they’re ready in case there are any potential side effects.”

And on Tuesday, Los Angeles County’s Public Health Department Director Dr. Barbara Ferrer warned of another potential hiccup.

“The only disappointment to date is that the doses we are planning to get this week, which we have not received yet, are much smaller than the dose than we anticipated,” she said.

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Brooks said there was also the matter of available resources.

“Right now the public health department is doing contact tracing,” he said. “They’re monitoring testing. They’re making sure that hospitals have oxygen. There’s so many other things they’re doing — and public health is generally underfunded — so now you have a situation where you have to do more with less.”

Back in Pasadena, the city has its own health department, which it said allows it to better target who’s inoculated based on federal guidelines.

“We vaccinated our firefighters last week and EMTs and frontline workers,” Lisa Derderian, spokesperson for the city of Pasadena, said. “That was very successful.”

Public health officials also said that vaccine hesitancy has contributed to the slowdown during the first phase. Between 20% and 30% of eligible frontline workers in Los Angeles County have decided to either wait or decline getting the vaccine.