By CBSLA Staff

LOS ANGELES (CBSLA) — Los Angeles County health officials said  Monday nearly 278,000 people in the county may be overdue for the second dose of their COVID vaccine.

“There are many reasons why this number might be showing up,” Ferrer said. “One is that some of these doses are actually second doses for people who received the first dose outside of L.A. County. Another is that people have simply forgotten to get their second dose. Some people may have been put off by side effects of their first dose or feel that one dose is as effective as they need and is going to be enough protection.”

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County officials also said people might be worried about side effects or believe that one shot is enough.

As of last week, health officials said more than 4.4 million people in the county have received at least one vaccine dose, and nearly 2.6 million had received a second dose.

The county announced it will continue to offer appointment-free, walk-up vaccinations at all of its large-scale sites through Thursday.

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People can get the appointment-free shots at the following vaccination sites:

  • Palmdale Oasis Recreation Center, 3850 E. Avenue S
  • The Forum, 3900 W. Manchester Blvd., Inglewood
  • Balboa Sports Complex, 17015 Burbank Blvd., Encino
  • College of the Canyons, 25000 Valencia Blvd., Santa Clarita
  • Cal State Northridge, 18343 Plummer St.
  • Eugene Obregon Park, 4021 E. First St., Los Angeles
  • Pomona Fairplex, 2370 E. Arrow Highway, gate 15
  • L.A. County Office of Education, 12830 Columbia Way, Downey

Doses are available for anyone 16 and over, although teens aged 16 and 17 must be accompanied by an adult.

Meanwhile Monday, the county reported four more COVID-19 deaths and 288 cases.

The numbers brought the county’s total death toll to 23,777 and the caseload to 1,231,806.

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(© Copyright 2020 CBS Broadcasting Inc. All Rights Reserved. City News Service contributed to this report.)