In San Antonio and across the country, coronavirus testing facilities and doctor offices were inundated with residents seeking to verify their negative status before the Thanksgiving holiday, but officials warn that a negative test for COVID-19 does not guarantee that a person hasn’t been exposed to the disease.

On Monday, Bexar County reported 709 new cases and an increase in the area’s positivity rate by 0.6 percentage points to 10 percent as the latest wave of infections continues to rise. Hospitalizations increased to 509, up 43 from Saturday; earlier this month that number was below 300. Health experts and other leaders fear the holiday season will lead to a higher peak and more sick or dead residents.

The increased positivity rate might trigger a shutdown of some bars, Bexar County Judge Nelson Wolff said Monday during his daily COVID-19 update with Mayor Ron Nirenberg. He said he will be discussing that course of action – affecting bars where food makes up less than 51 percent of sales – with health officials this week.

Wolff encouraged residents to celebrate Thanksgiving at home.

“If you’re planing on travel, don’t do it,” he said.

Spending the holidays without friends or family members is “really terrible,” Mayor Ron Nirenberg told the San Antonio Report, “but not as terrible as it would be to experience what thousands of our neighbors have already in losing a loved one to this virus.”

While air travel is significantly down compared with this time last year, the number of travelers screened at U.S. airport security checkpoints topped 1 million on Friday for the second time since the beginning of the pandemic in March, according to the Transportation Security Administration.

Nirenberg urged residents, including those who have tested negative, to wear a mask and practice social distancing around people they don’t live with.

Even the most reliable tests can result in what is essentially a false negative if it’s taken too soon after exposure, said Dr. Jan Patterson, an infectious disease specialist with UT Health San Antonio.

“If they test negative, that means they’re negative when they got tested,” Patterson said. “The problem is that [coronavirus] has a 14-day incubation period. Most cases are going to show up [on a test] within the first 10 days – but many cases are going to be asymptomatic” and may not.

Even if someone has the virus and its symptoms, she said, there is a roughly 20 percent chance of a negative test if it’s taken before the eighth day after exposure.

“So if you’re going to see grandma, you’re basically taking her everywhere you’ve been in the last two weeks,” she added. A negative test is “not really a free ticket for exposing everybody … to where you’ve been over the last two weeks.”

The safest alternative is to stay around people you live with and host a virtual Thanksgiving gathering over videoconference or phone – but there are ways to celebrate safely together.

Patterson’s family is following the Centers for Disease Control and Prevention’s recommendations by keeping it small (six to eight people), outdoors, limiting the number of people serving and handling food, and continuing to practice mask-wearing, hand hygiene, and physical distancing.

“It looks like it’s going to be a nice day, so hopefully we can all go outside and keep our distance,” Patterson said.

Other recommendations include seating guests at separate tables by household and using single-use items for serving food.

Nirenberg said he will be staying home with his son and wife for Thanksgiving, inviting extended family to the table via Zoom.

“[Testing] in some ways has been seen as an elixir for going back to normal life and that just isn’t the case,” he said. “That’s something that I think is difficult for us to have to admit given how much people have been through with this virus.”

It’s unclear if Gov. Greg Abbott will allow cities with increasing coronavirus prevalence to further shut down nonessential businesses, Nirenberg said.

“The state executive offices are loath to relinquish the control that they’ve exhibited over the last six months of this pandemic,” he said. “Our charge is to continue to be aggressive with information and transparency.”

During the nightly COVID-19 update, Nirenberg said the City has recently doubled capacity to conduct proactive enforcement of public health orders.

“At the end of the day, it comes down to you,” the mayor said to viewers. “We cannot stop this virus if you don’t change your behaviors. If you don’t heed the warnings this Thanksgiving holiday, you or your loved ones could be spending Christmas in the hospital. That’s just the facts.”

Senior Reporter Iris Dimmick covers public policy pertaining to social issues, ranging from affordable housing and economic disparity to policing reform and mental health. She was the San Antonio Report's...