Her Majesty and her daughter-in-law spoke to eye care specialists working to save the vision of some of the one billion people experiencing eyesight issues worldwide.
The 94-year-old monarch, wearing a delphinium blue dress by Angela Kelly, was all smiles as she heard how a fund created to mark her Diamond Jubilee has helped save the sight of millions of people.
WATCH: Sophie runs the first 1.5 miles of the virtual London Marathon 2020
The £100 million Queen Elizabeth Diamond Jubilee Trust was set up in 2012 by governments and other donors across the Commonwealth to mark her 60 years on the throne.
Since then it has paid for more than 22 million people in Africa and the Pacific to receive antibiotics to beat trachoma, which causes blindness, while thousands more had sight-saving surgery.
"I'm glad that the Queen's Jubilee has been able to do some good help for this particular thing of eye care," the Queen said, joining the call from the Oak Room at Windsor Castle.
Sophie, who is global ambassador for the International Agency for the Prevention of Blindness, told her: "I think that’s somehow underplaying it. It's been incredible."
The Queen and the Countess of Wessex on the video call
The royal women spoke to Jelikatu Mustapha, 33, one of only four ophthalmologists in Sierra Leone, Vengadesen Natrajan, a patient care and quality manager at Aravind Eye Hospital in Pondicherry, India, and Jennifer Merryweather, a senior policy advisor at the Fred Hollows Foundation in Australia
The Queen told them afterwards: "It’s been very interesting and I must say I am very impressed by all the work that is going on. Well done."
The royal family shared highlights from the call
Two days after the 7 October call, Buckingham Palace announced that the Countess was self-isolating at home after coming into contact with someone who subsequently tested positive for Covid-19.
Sophie was not experiencing any symptoms but "following all relevant government guidelines," a spokeswoman confirmed.
She had not come into contact with other members of the royal family beyond her husband Prince Edward and children Lady Louise Windsor and James, Viscount Severn, for at least a week prior to learning she might have been exposed to the virus.
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