SACRAMENTO (CBS13) – In the middle of the holiday travel rush, there’s another kind of rush as well: the rush for the COVID-19 booster shot.

Many booster shot clinics have seen unprecedentedly long lines as families rush to be doubly vaccinated for the holidays.

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Particularly walk-in clinics have seen car lines around the block with the high demand for these booster shots.

One clinic in San Mateo saw particularly long lines.

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“It’s worth getting in line,” said one woman, despite waiting for what might as well be the drive-thru at In-N-Out during rush hour.

By noon, the clinic had to turn people away due to an inability to vaccinate so many.

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Being the first weekend the booster shot was available to all adults, lines were to be expected. However, many clinics did not realize that the demand would be this high.