People in the United States who were the first in line to receive the coronavirus vaccine are now getting their second and final shots.
Inoculations with the Pfizer-BioNTech vaccine began in the US on December 14. The two shots are to be administered three weeks apart.
Critical care nurse Sandra Lindsay received her second jab in New York on Monday. She was among the first US medical workers who got the first shot. Lindsay said she wants everyone to know that the vaccine is safe.
The US Centers for Disease Control and Prevention says more than 15 million doses of the COVID-19 vaccine had been distributed nationwide as of Monday.
But it says the total number of doses received stood at just over 4.5 million, falling far short of the federal government's target of giving the first shots to 20 million people by the end of December.
A vaccination center in Florida ran out of stock in just two hours on Monday, while people hoping to get inoculated arrived in vehicles, forming a waiting line several kilometers long.
Experts say the government should offer funding, staffing and guidance to state health authorities and medical institutions to make sure the vaccine is delivered quickly to as many people as possible.