The Countess of Wessex is self-isolating at home after coming into contact with someone who later tested positive for coronavirus, Buckingham Palace has said.
Sophie will be isolating at her Bagshot Park home, a Surrey mansion where she lives with husband Edward and their children Lady Louise and James, Viscount Severn.
The Prince of Wales contracted Covid-19 in March and suffered from mild symptoms – losing his sense of smell and taste for a period.
A palace spokeswoman said: "Earlier this week the Countess of Wessex came into contact with someone who has subsequently tested positive for Covid-19.
"Her Royal Highness is not experiencing any symptoms, but is following all relevant Government guidelines and is self-isolating at home."
It is understood the countess – whose home is close to the Queen's Windsor Castle residence – has not seen any members of the monarchy this week, outside of her immediate family.
The NHS advises on its website Covid-19 tests should only be taken by those who have symptoms or have been asked to be tested. The self-isolation period is 14 days for those told to stay at home by NHS Test and Trace.
It is not known how Sophie was notified she had come into contact with someone who later tested positive.
But she has since been contacting people she met after that encounter to make them aware.
The past week has been a busy period for the countess who carried out a string of engagements in Surrey, London and Leicester which would have brought her into contact with many people.
On Sunday she jogged 1.5 miles in Windsor Great Park alongside a London Marathon runner raising awareness for Mencap, a disability charity she supports as patron.
The following day she visited a school in Hindhead, Surrey to mark World Teachers' Day and on Tuesday in her role as patron of the Chartered Management Institute attended the organisation's president's awards in west London.
Sophie travelled to Leicester on Wednesday visiting the National Space Centre to mark World Space Week.
Residents of Leicester have been told not to mix with people outside of their household either indoors or in a private garden, and avoid socialising with other households in public venues.