County Judge Lina Hidalgo made the announcement Monday afternoon, citing the latest Centers for Disease Control data that omicron cases in the U.S. are doubling every two-to-three days.
She said the county has seen a rapid increase in new COVID cases and positivity rate.
The orange threat level is Harris County's second highest COVID threat indicator. It signifies an ongoing, uncontrolled level of COVID in the county.
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Under the orange threat level, residents should minimize contact with others and avoid medium or large gatherings, health officials say.
"Unfortunately, the omicron variant has arrived in Harris County in full force," Hidalgo said. "These trends are understandably frustrating - especially as we close out the year with friends and family. But we can still blunt the force of this latest wave if we take action. As we approach Christmas and New Year, consider giving yourself and your family the gift of health by getting your booster, getting tested before any gatherings of people outside of your household, and wearing a mask. It could very well save your life or that of a loved one."
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Hidalgo is urging residents get their booster shots as soon as possible, especially those 65 and older. Residents who have not received the first dose of the COVID vaccine are also encouraged to do so immediately.
The county says regardless of vaccination status, residents should wear a mask and get tested before attending holiday gatherings.
For more information on Harris County's COVID threat level and where to get a vaccine, visit ReadyHarris.org.
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