Experts hope to assess vaccine safety and whether protective antibodies are passed to babies.
More than 25 million people in England have been vaccinated with their first dose.
Experts say the mutant strain could enjoy a ‘transmission advantage’ as more areas in England enter Tier 3.
It has been described as ‘one of the greatest challenges the NHS has ever faced’.
The images were issued by Public Health England and were taken at a secure location.
The social media giant warned it will ‘not be able to start enforcing these policies overnight’.