Mexico began administering the first 3000 doses of the Pfizer-BioNTech vaccine on Thursday in a broadcast ceremony in which Maria Irene Ramirez, 59, got the first shot, under the watchful eyes of military personnel who escorted the vaccine shipment.

"This is the best present I could have received in 2020," said Ramirez. "The truth is we are afraid, but we have to keep going because someone has to be in the front line of this battle."

Assistant Health Secretary Hugo Lopez-Gatell waxed poetic, saying, "Today the stage of the epidemic and its treatment changes, to a ray of hope."

Zoe Robledo, director of Mexico's social security system, called it "an unforgettable Christmas. We are sure this is going to be the beginning of the end of the pandemic."

Other doctors and nurses rolled up their sleeves in the chill morning air at outside vaccination stations in the cities of Toluca and Queretaro.

The country's 1.4 million health workers will be the first to get the shots, followed by the elderly, those with underlying health conditions that make them more vulnerable to the disease, and teachers.

Foreign Relations Secretary Marcelo Ebrard said Mexico was the first country in Latin America to get the vaccine, though others were close behind.

Chile also began its inoculation program on Thursday, with 42-year-old nurse Zulema Riquelme getting the first jab as President Sebastian Pinera looked on.

Chile said it had received 10,000 doses of the Pfizer vaccine, and has a deal for a total of 10 million. Health workers and the elderly will be first in line.

In Costa Rica, which is the third country in the region to begin using the Pfizer vaccine, the first shot was given Thursday to Elizabeth Castillo, 91.

Argentina, which has run into problems obtaining the Pfizer vaccine, received a flight carrying 300,000 doses of the Russian Sputnik V vaccine.

Argentina plans to become the first country in Latin America to administer the Russian vaccine starting next week. It won't yet be given to people older than 60 due to a lack of testing data.

While Mexico got only 3000 doses of the Pfizer vaccine in the first shipment Wednesday, Ebrard said about 53,000 more doses would arrive by Tuesday, about 1.4 million doses in January and a total of about 11.75 million by mid-year.

Ebrard said two vaccines are currently undergoing Phase 3 studies in Mexico and another three are awaiting approval to start.

Other countries around the region are engaged in testing several vaccines, in studies that involve tens of thousands of volunteers.

Latin America has been among the regions hardest hit by the pandemic.

Mexico reported over 1.35 test-confirmed cases so far and 120,311 deaths, the fourth-highest toll in the world. However, estimates based on excess deaths this year suggest Mexico's real death toll is closer to 180,000.

Argentina has 1.5 million cases and over 42,000 deaths, while Chile has seen 590,000 cases and 16,000 deaths.

Australian Associated Press