PITTSBURGH, Pa. (WHTM)- Shipments of the Pfizer vaccine began on Sunday and were ready for use by Monday morning. A shipment of over 900 doses arrived at UPMC Children’s Hospital in Pittsburgh. Charmaine Pykosh, a 67-year-old advanced nurse practitioner was the first of five UPMC health care workers to get the vaccine.

“It was exciting and relieving,” said Pykosh. “I’m honored to do this and appreciative of UPMC to have this.”

As of now, UPMC says there weren’t enough vaccines in the first shipment to vaccinate all of its health care workers, but expects that to change by the end of January.

“We’re excited and optimistic about the likelihood that we will have enough vaccines very soon to reach all of the health care workers,” said Dr. Graham Snyder, medical director of infection prevention and hospital epidemiology at UPMC.

The Pfizer vaccine requires two doses. UPMC expects the second half of doses to be delivered in two weeks.

“This is unprecedented how fast and how broad the vaccine efforts have been,” said Snyder. “We have more vaccine candidates than anyone could have imagined and they’re being developed and being demonstrated to be safe and effective.”

WellSpan says it’s expecting its first shipment of the Pfizer vaccine on Tuesday at WellSpan Good Samaritan Hospital and shipments to its other locations by the end of the week.

Penn State Health says it’s anticipating the arrival of the Pfizer vaccine the week of December 20.