"Level 1 signifies a severe and uncontrolled level of COVID-19 in the County, meaning outbreaks are present and worsening and public health capacity is strained or exceeded," according to Harris County Public Health.
"We are in the midst of another COVID-19 tsunami," Hidalgo said during a news conference. "It's like nothing we've seen before in this pandemic."
Hidalgo said she made the decision because hospitalizations and ICU cases have spiked at area hospitals, along with the positivity rate.
"The 14-day average for COVID-positive ICU cases is now 18.1%; the positivity rate is now 35%," Hidalgo said. "For the sake of our hospitals and for the sake of our workforce, we have to sound the alarm once again."
This is the third time Harris County has been at level red, but Hidalgo said it could have been avoided this time if more people would get vaccinated and boosted.
“We owe it to our nurses, doctors, and teachers to take steps to protect ourselves and give them a break. If you have been on the fence about getting vaccinated, now is the time to roll up your sleeve."
Hidalgo also urged unvaccinated residents to mask up and avoid "all gatherings." Those who are vaccinated are asked to wear masks while indoors in public places and to avoid unvaccinated people.
Update on rapid antigen tests and PCR tests
Hidalgo said 120,000 rapid antigen tests will be provided to school districts across the county. She said the tests will help students and staff who are exposed to COVID-19 return to school sooner if they test negative.
She said thousands of PCR tests are still readily available at more than 10 county-wide sites. Another testing site will open Tuesday at Planet Ford Stadium in the Spring area.
No lockdowns expected
While Monday's announcement moves Harris County to the highest threat level for the first time, the lockdowns and closings residents experienced in 2020 aren't likely to be repeated.
Under statewide orders from Texas Gov. Greg Abbott, local governments cannot enforce their own stay-at-home orders, as Abbott allowed them to do in the early stages of the pandemic.
Abbott's latest executive order related to the COVID-19 response, issued in July 2021, forbids local government entities from mandating closures and vaccinations.
"Business activities and legal proceedings are free to proceed without COVID-19-related limitations imposed by local governmental entities or officials," the order states.
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