"We have many of the vaccines that your normal doctor's office wouldn't have," said Evelyn Malone-Hicks, the director of clinical operations at the clinic.
That includes an allocation of the COVID-19 vaccine from the state.
Since December, the clinic has successfully vaccinated 1,000 people.
When they found extra vaccine in their over-filled Moderna vials, they gave that out too.
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"While we thought we had ten per vial, there would be opportunities to have eleven, twelve, sometimes even 15," said Malone-Hicks.
The clinic, following CDC guidelines, gave out every extra dose of the vaccine, not letting any go to waste.
"What we ended up doing was calling from our wait list and getting in new doses, and therein lies our particular problem. The state is not sending us second doses for those new first doses we were able to generate," explained Malone-Hicks.
She said they now have about 100 patients due for a second vaccine that won't be arriving.
We spoke with the Texas Dept. of State Health Services about the clinic's problem. A spokesperson says this is a common scenario, and they are not shipping small batches of additional vaccine for extra second doses to individual providers.
Instead, state officials say they want those patients who need a second vaccine to go to a county vaccine hub.
There are five vaccine hubs in Harris County and one in Fort Bend County.
The spokesperson says they are working with individual providers in this situation to get their patients to the county hubs.
"The people in Stafford did the right thing. You should not let any vaccine go to waste," said Dr. Peter Hotez with Baylor College of Medicine.
Even with patients due for their second dose next week, Hotez said going past the 28-day wait time between the two Moderna doses is safe.
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"From everything we know about vaccines, delaying a second dose by a few weeks is not harmful. In fact, (it) may even improve the immunogenicity of the vaccine," he said.
The CDC now says patients can go up to 42 days between their first and second doses of the COVID-19 vaccine.
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