The following is from a more recent BBC News article:
What went wrong?
Critics have accused the Piñera government of getting caught up in triumphalism over the vaccine rollout and of having loosened coronavirus restrictions too fast.
Like governments across the world, ministers here faced difficult choices.
Chile's borders had been closed - bar for a few exceptions - from March to November 2020. But after a strict lockdown had driven the rolling seven-day average down to 1,300 cases in November, the decision was taken to reopen them, including to international tourists.
Chileans were also given special holiday permits to travel more freely around the country during the southern hemisphere summer holidays after some experts argued it was important for people's mental health.
Restaurants, shops, and holiday resorts were opened up to kickstart the faltering economy.
Fast, but not in time for the holidays
And while the vaccination rollout has indeed been fast, it only started in late December, with front-line health care workers, those over 90, and teachers first in line.
So the vast majority of Chileans would not yet have been vaccinated by the time they met up with relatives and friends for their summer holidays in January and February.
Chile's main holiday season is in January and February
Add to that the spread of new, more easily transmittable variants of the virus such as the P.1 variant, which is thought to have emerged in Brazil's Amazonas state in November.
What is the Brazil variant and do vaccines work against it?
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Dr Susan Bueno, a professor of immunology from the Pontifical Catholic University, says the recent surge is "a multi-factor issue", but that she thinks the new variants are having a "huge impact".
She says the message about how to prevent contagion, such as wearing masks and washing your hands, was also somewhat neglected during the summer months in Chile. That, she explains, "is probably one of the causes of the outbreaks we are seeing now".
CoronaVac confusion
There is also confusion about how the vaccine that the vast majority in the country has received works, Prof Bueno adds. More than 93% of the doses administered in Chile so far have been CoronaVac, produced by the Beijing-based biopharmaceutical company Sinovac.
Data on the efficacy of the CoronaVac vaccine is varied. Brazilian trials suggested an efficacy rate of around 50.4% but results from late-stage trials in Indonesia and Turkey suggested a much higher rate - between 65% and 83%.
What do we know about China's Covid-19 vaccines?
China official says local vaccine efficacy is low
A study published by the University of Chile last week (in Spanish) looked at the level of protection the vaccine offered after the first and the second doses.
It suggested CoronaVac was 56.5% effective in protecting people against infection two weeks after they had received their second dose, but the figure was only 3% in the timespan between the first and second doses.
This may give a key clue as to why cases may still be on the rise in Chile, where more than 7.6 million people have received the first jab, but the number of those who have had both the first and second doses is much lower.