FORT WORTH (CBSDFW.COM) – Fast-moving variants of COVID-19 are spreading across the country, leading to growing evidence that having the virus once doesn’t mean you can’t get it again.

“Definitely it is a concern,” said Dr. Nikhil Bhayani, an infectious disease specialist with Texas Health Resources. “It’s not something you know we can ignore.”

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Dr. Bhayani said that while reinfections can happen, they are still relatively rare. Other doctors agree.

“So at this point in time I don’t think we have enough data for anyone to feel completely scot free, completely immune to COVID,” said Dr. Crystal Howell, a professor who teaches about infectious diseases at UNT Health Science Center.

Both doctors say having had COVID-19 or getting a vaccine will at least offer you some protection, but it’s just too early to know how much the new variants will change things.

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“I hope people keep in mind is that it is not as straightforward as yes or no,” said Dr. Howell. “It’s not so dichotomous unfortunately.”

It’s also unclear just how long immunity lasts after natural infection.

That is why both doctors said everyone needs to keep taking safety precautions.

One study in South Africa found new infections with a variant in about two percent of people who had been sick previously.

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The doctors said the bottom line is that there’s still so much not known about COVID-19.