They examined the virus' two waves. The first wave was from March to mid-May and the second wave started after Memorial Day.
WATCH: ABC13's Marla Carter talks with Dr. David Persse about COVID-19 mutation
Researchers noticed a mutation from the first wave compared to the second wave, and the second wave showed it was more contagious.
"That mutation helps the virus spread faster," said Dr. Jim Musser, Chair of Pathology and Genomic Medicine at Houston Methodist Hospital.
While the virus may spread faster, it is not more deadly than it was prior to the mutation.
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"The one mutation in the spike protein results in an increased amount of virus in the upper respiratory tract and that's probably helping it spread faster, but it doesn't make it appear to cause worse disease, or to invade better," said Dr. Musser.
Dr. Musser said the study examined more than 5,000 specimens of the virus, making it the largest mutation study in a metropolitan area. He said it's critical that the virus mutation be tracked and observed.
"To have as much information as possible about our enemy, this virus," said Dr. Musser.
Dr. David Persse with the Health Authority for the Houston Health Department said the virus mutation is common. It's one reason we get a flu shot every year.
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"The virus basically hijacks the cells' genetic system and starts making many, many copies of itself. Every time it makes a copy of itself, it runs the risk of making an error, which would then be a mutation," said Dr. David Persse.
For many of the mutations, you don't even notice a change in the virus. However, in this case, the mutation shows the virus is more contagious, the big concern would be if a mutation caused the severity to worsen. Dr. Persse said it's all the more reason we need to stop this virus from spreading because every time someone gets it, there's an increased chance for mutation.
"Every time somebody becomes infected there are then thousands, if not hundreds of thousands, if not millions of opportunities for another mutation to occur so we don't want that," said Dr. Persse.
He says it's all the more reason we need to wear our masks and social distance.
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