Winter storms that have led to more than two dozen deaths and left millions of people without power are also likely to cause "widespread delays" in Covid-19 vaccine shipments in the coming days, the Centers for Disease Control and Prevention said Tuesday.
"Due to the severe winter weather currently impacting a large swath of the country, the U.S. government is projecting widespread delays in COVID-19 vaccine shipments and deliveries over the next few days," CDC spokesperson Jasmine Reed said in an email.
"Shipping partners are working to deliver vaccine where possible, contingent on local conditions, but the adverse weather is expected to continue to impact shipments out of the FedEx facility in Memphis, Tenn., as well as the UPS facility in Louisville, Ken., which serve as vaccine shipping hubs for multiple states," Reed said.
As of Tuesday evening, more than 39 million people in the U.S. had received one or more doses of a vaccine, according to the CDC. Around 15 million have gotten both doses.
In Texas, where more than 4 million people are in the cold after the weather system crippled the state's electric grid, the Department of State Health Services said this week's shipment of vaccine doses wouldn't arrive until Wednesday at the earliest.
"No one wants to put vaccine at risk by attempting to deliver it in dangerous conditions," the department tweeted Tuesday.
On Monday, officials in Harris County, which is home to Houston, scrambled to administer thousands of doses of Moderna's vaccine after a power outage and a backup generator failed.
"I literally dropped everything, got everything on and sprinted here," a student at Rice University, one of the five locations where the doses were administered, told NBC affiliate KPRC of Houston.
Chicago closed all city-operated vaccination and testing sites Tuesday because of the weather and said shipments to the city will be delayed — although it expects to catch up quickly.
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The governors of Ohio and Florida also said shipments would be affected. Colorado's health department said delays would affect the state's allocation of 133,000 vaccine doses that had been expected to arrive through Thursday.
In Pennsylvania, the Geisinger health system rescheduled appointments at some facilities that had been scheduled for Wednesday and Friday. Appointments in Monmouth County, New Jersey, for Wednesday were rescheduled for Friday.
When a major winter storm created blizzardlike conditions in parts of Pennsylvania and the Northeast this month, there were also some vaccine resupply postponements, closings of vaccination sites and reschedulings of appointments.