Ahead of the holidays, more people are getting together and want to know if they're free of COVID-19 before visiting their relatives. 

More people are buying at-home COVID-19 test kits, according to Hidalgo County Health Authority Dr. Ivan Melendez.

"One of the problems we're having now is that supplies are running low because more people are self-testing,” Dr. Melendez said. “And let's remember that those people that can afford it can go to the pharmacy can pay $20, 25 to get the test. The problem are those people who don't have insurance or just don't have the money."

Dr. Ivan Melendez says if you pick up an at-home test kit, know that there are limitations. For example, rapid tests, which look for antigens, sometimes get misleading results.

"There is about a 15 percent false negative rate,” Dr. Melendez said. “Out of 100 people that test negative from a home test, 15 are really positive. There's about 1 out of 100 that are false positive. People test positive, and they really don't have an infection. Regardless, doing the take-home test does not tell you if you're at that moment actively infected or not."

The most reliable test is the PCR test, which tests for pieces of the virus' DNA. Melendez says if you really want an answer, that's the test you need.

"At-home tests that are from the pharmacy are helpful to screen, but should only be a screen," Melenez said.

Dr. Melendez says if you suspect you are sick, don't just get the rapid test.