Window for second vaccine dose two to three weeks long

TEXARKANA — Anyone who missed their second dose of coronavirus vaccine because of this week’s winter storms still has weeks to get it.

Those who get a first dose of the vaccine developed by pharmaceutical company Pfizer must wait at least 21 days before getting the needed second dose, and those who get Moderna’s vaccine must wait 28 days.

But in both cases, recipients have up to 42 days from the first dose to get the second, according to the Centers for Disease Control and Prevention.

That means the optimal time window for getting the second Moderna dose is two weeks long and that for the Pfizer vaccine lasts three weeks. The window can be even longer, according to CHRISTUS St. Michael Health System, Texarkana, Texas’ state-designated vaccine hub.

“In some cases, depending on clinical circumstances, the second dose of vaccine can be administered up to 90 days” after the first, a St. Michael spokesperson said Thursday. Whether someone can receive the second dose that long after the first should be evaluated by a clinician on a case-by-case basis.

Because of the weather,

St. Michael postponed a

second-dose clinic originally scheduled for Thursday and today until Feb. 26. A 1,000-dose-a-day weekend clinic, first slated for Saturday and Sunday, also has been postponed, until Feb. 27 and 28. St. Michael is notifying those who had appointments about the changes, and they need not take any action.

The hospital is storing second doses in reserve for those who received a first dose there.

The storms have not disrupted the refrigeration and freezing needed to preserve

St. Michael’s vaccines.

Other places offering coronavirus vaccinations by online appointment, as any doses are allocated to them by state health agencies, include local Walmart and CVS pharmacies and College Hill Drug on the Arkansas side.