The rapid test explained, and how to keep families safe
Each week, Chronicle health reporters field questions about the latest on COVID-19, vaccines and pandemic living. In this week’s COVID Help Desk: what you should know about rapid tests and keeping your family safe this holiday season.
How accurate are COVID rapid tests?
Once scarce, COVID rapid tests are now more readily available at pharmacies around Houston. Health experts recommend using them on unvaccinated relatives as a stop-gap measure before holiday get-togethers.
The tests are less sensitive — and more costly — than PCR tests. They may not pick up on an asymptomatic infection if someone is carrying a low viral load. But they are good at detecting when someone is highly contagious and most likely to infect others.
Rapid tests work by identifying COVID-specific viral proteins in a person’s nasal cavity, said Dr. Linda Yancey, an infectious diease specialist Memorial Hermann. A positive test result is clear cut: “You have COVID,” she said. A negative test result is slighly less clear, as the testee could simply be in the early stages of an infection.
But the good news, Yancey said, is that “a negative test means you are almost certainly not able to infect someone at that time.”
Many Houston pharmacies carry the BinaxNOW test from Abbott Laboratories or the QuickVue test from Quidel. While the CVS and Walgreens websites show available test kits by Zip code, it’s still a good idea to call the store to confirm it still has them in stock.
If possible, encourage unvaccinated family members to book a free PCR test at their local pharmacy ahead of your next gathering. A single rapid test can cost around $25, making it an expensive investment in holiday health. How can I protect myself
while visiting unvaccinated relatives?
“A fully vaccinated person with two doses and possibly a booster should feel fairly confident they are going to be relatively safe gathering with unvaccinated people,” said Dr. Melanie Mouzoon, managing physician for immunization at Kelsey-Seybold Clinic.
Mouzoon recommending asking whether unvaccinated family members have already had COVID. In general, those who have recovered from the virus are “unlikely to be spreading it.” The
Lone Star state’s severe summer outbreak left many unvaccinated Texans with a measure of natural immunity.
The vaccine expert also recommended making the “reasonable request” that unvaccinated relatives take a rapid COVID test or schedule a PCR test prior to gathering.
“It’s better to get a rapid test than no test at all,” she said.
The majority of breakthrough cases in vaccinated people are mild, and may go undetected, especially in healthy people under the age of 65. For those groups, the three approved vaccines — Pfizer, Moderna and Johnson & Johnson — have been effective.
But for the elderly or immuno-compromised, breakthrough infections are a far riskier prospect. People with obesity, heart disease or other complicating health conditions should be extra cautious — and “get boosted” as soon as possible, Mouzoon said.
My child is unvaccinated or partially vaccinated. How do I protect them while traveling this holiday season?
Children between the ages of 5 and 11 are considered fully vaccinated two weeks after their second dose of the COVID vaccine. That means most children will not be protected in time for the holidays.
But just like attending school in person, kids can safely travel if their caretakers take the proper precautions, said Dr. Pedro A. Piedra, a virologist at Baylor College of Medicine.
The experts recommended eating outdoors if weather permits and having kids wear their masks indoors around unvaccinated or immuno-compromised relatives. “You’re trying to have a joyful time and not regret it later,” Piedra said.
If traveling by air, the doctors recommended avoiding long layovers and social distancing when possible in airport terminals. While airplanes have advanced filtration systems in place, terminals often lack adequate ventilation. Yancey, of Memorial Hermann, advised travelers with kids to avoid snacking in the airport.
“Buy your food and eat it on the airplane, she said. “You are going to be safer on the airplane.”
The infectious disease specialist also encouraged parents to inoculate kids against influenza, which targets young children. After a historically light flu season in 2020, a resurgence is expected this winter. The combination of COVID, flu and a return to holiday normalcy has doctors concerned.
“This is going to be a very fraught holiday season,” Yancey said.