DALLAS (CBSDFW.COM) – The Texas Department of State Health Services said Wednesday, May 5, more than 630,000 Texans are overdue for their second COVID-19 vaccine shot.

It averages out to be nearly 6% of those getting vaccinated.

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“It’s really important when you look at the numbers, 5 or 6% could be the difference between having protection in society versus still having a lot of cases out there,” said Robert Hancock, President of Texas College of Emergency Physicians.

The numbers are causing concern for the group.

Last week, they reported that 570,000 people were overdue, now that number has increased by more than 60,000.

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They say it could be for a number of reasons.

“There’s a perception out there that getting one shot gives you enough protection and that’s just simply not true with the two-shot dosing,” Hancock said.

The group says most people’s immune systems need that second dose to fight COVID-19 off.

And that without it, chances of getting the virus dramatically increase.

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“You still have about a 5% chances of contracting COVID with both shots, but those are minor cases. With one shot, it drops down to 50% protection.”

Nicole Nielsen