Now, a county doctor says he believes booster shots should be a "necessary" part of the primary series of vaccine shots.
SANTA CLARA COUNTY, Calif. (KGO) -- The omicron variant has made its way to Santa Clara County.
Health officials say at least one person has tested positive, while the variant was also detected in the county's sewer-shed.
Santa Clara County Health Officials always said it wasn't a situation of if, but when. And the when is now.
"Yesterday we received our first of a resident of Santa Clara County with the omicron variant," Santa Clara County Public Health Officer Dr. Sara Cody said.
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Dr. Cody said the individual was vaccinated, wasn't boosted and experienced mild symptoms while in self-isolation.
The symptoms began November 30 and the county's sequencing system learned Thursday it was in fact an omicron positive case after the individual tested on December 1.
"The person with the omicron variant had traveled to Florida, most likely where they were exposed," Dr. Cody said. "So, a community exposure in Florida rather than an international exposure."
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The county is utilizing positive tests through people, as well as a surveillance system through county sewer-sheds, to detect coronavirus and variants.
The first detection of omicron in the sewer-shed was also found Thursday, near where the positive individual lives in North County.
Omicron's emergence has made the importance of boosters that much greater.
"What we're finding now is that having just that primary series, the two doses, it's not enough," Santa Clara County COVID-19 testing and vaccine officer Dr. Marty Fenstersheib said.
Dr. Fenstersheib says only 39% of the county has received their booster shot.
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The detection of omicron was expected by these health officials, but they say residents can do their part to protect themselves and keep this from getting worse.
"We really want to urge people that they need the booster," Dr. Fenstersheib said. "Now, we want to consider it part of that primary series and we really need to add that on as a necessity."
"Vaccinate and boost, mask, test, ventilate and distance," Dr. Cody said.