With the Queen approaching her 96th birthday in April, there was always going to be concern about her contracting Covid, but the monarch has tested positive against a different backdrop from when the virus arrived in the UK.
She was given a booster for her vaccinations as recently as December, and could also have been given a drug approved by UK authorities.
She will be cared for at Windsor Castle by staff from the royal household.
The Queen's physician, Sir Huw Thomas, who is a consultant at St Mary's hospital in London, and the head of the medical household, will be at the forefront of decisions about her care.
He might choose to prescribe one or more of the antivirals that are designed to protect the most vulnerable.
Despite the public being told that the Queen is suffering from a cold, experts stress that mild Covid infections can begin with mild symptoms.
Prof Paul Hunter, an infectious disease expert at the University of East Anglia, said that with anyone in their 90s, even if triple-vaccinated, there would be concerns that they could gradually decline.
There are a number of antiviral drugs around at the moment, and you would almost certainly be considering giving them.
Ronapreve, which was approved in August last year, and which contains types of proteins called monoclonal antibodies, are drugs that could be considered. It reduces the risk of hospital admission or death by 70% in people with mild to moderate Covid-19.
There are two drugs approved in the UK in the last part of last year that have been shown to be effective.
Hunter said that the first two drugs would need to be given within three days for them to have the best impact.
In June 2020 the Queen was pictured riding a pony at Windsor while isolating, she has a strong constitution and occasional ill health.
During an in-person audience on Wednesday, the monarch remarked, "Well, as you can see, I can't move."
The Queen was said to have been feeling stiff, rather than having injured herself or been unwell.
She missed the Cenotaph event due to a back injury. She attended a reception for business leaders at Windsor Castle. She was admitted to the hospital for a night after she canceled her trip to Northern Ireland for medical advice.
She only carried out light duties on doctors' orders for three months. She was in the hospital for the first time in eight years. She was 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217 800-273-3217
Age is not the only characteristic that influences individual risk from Covid, which should be considered along with other characteristics that influence risk, including sex, ethnicity, and some pre-existing medical conditions.
The charity pointed out that older people were less likely to have coronaviruses in the last few months of last year. The charity said that protection against serious illness remained high for at least five months, and urged the elderly to get a booster.
Buckingham Palace wouldn't say when the Queen received a booster or if she had one. In a video call with health officials, the monarch encouraged people to think about other people rather than themselves, and to get the Covid-19 jab, as she expressed her enthusiasm in public for vaccinations last year.
She said that once you have had the vaccine, you are protected.