The Queen and Covid: How serious is the virus for 95-year-old monarch?

Queen Elizabeth II cuts a cake to celebrate the start of the Platinum Jubilee at Sandringham House on February 5, 2022. Photo / Getty Images

Queen Elizabeth II tested positive for Covid-19 on Sunday and is experiencing mild symptoms, Buckingham Palace says.

Covid-19 is a disease that disproportionately affects the old, preying on frailties and exploiting vulnerabilities.

In the last three months of 2021, almost 80 per cent of all Covid deaths were in over-65s.

But an individual's risk varies depending on many factors, including pre-existing health conditions and vaccination status.

The Queen, who turns 96 in April, has enjoyed remarkably good health throughout her reign, but at the end of last year took a period of rest following medical advice after falling ill.

The Queen records her annual Christmas broadcast at Windsor Castle, December 2021. Photo / AP

She spent time in hospital and underwent medical tests for an unknown health issue, and has acknowledged she suffers from mobility issues. Her diary is now paced to ensure she does not overstretch herself.

No specific pre-existing conditions increasing risk

However, the Queen is not believed to have any of the conditions which specifically increase the risk from Covid, such as diabetes, which is listed as a co-morbidity in one in four Covid hospital deaths.

And she is understood to be triple-jabbed, giving her the maximum amount of protection from Covid.

Data from the University of Cambridge's MRC biostatistics unit estimates the infection fatality rate — the number of people who die after contracting Covid-19 — is 3.4 per cent for all over-75s.

But figures from the UK's Office for National Statistics (ONS) show that for every 100,000 people over-90 who have been boosted, there would be 343 expected deaths, or a 0.34 per cent risk of death.

This metric, known as the age-standardised mortality rate, is 10 times higher for an unvaccinated person, with 3,237 deaths expected per 100,000, or 3.2 per cent.

Symptoms consistent with Omicron strain

According to the statement from Buckingham Palace, the monarch is suffering from mild, cold-like symptoms.

This is consistent with the Omicron strain of Covid, the most recent and dominant variant which now accounts for almost all cases. Fortunately, it is intrinsically far milder than previous strains and more likely to present as a cold.

Both the Queen's eldest son Prince Charles, 73, and her 74-year-old daughter-in-law Camilla, Duchess of Cornwall contracted Covid earlier this month. Photo / Dean Purcell

For over-80s, a person is 60 per cent less likely to be hospitalised with Omicron than if they caught Delta, the previously dominant strain, research from Cambridge's MRC and the UK Health Security Agency shows.

Since the start of the pandemic in March 2020, more than 21,000 95-year-olds have died in the UK overall, but just 2432 of these were because of Covid - around one in nine.

In December, the last month for which there is data, 26 95-year-olds died from Covid.

In total, 967 95-year-olds died from any cause, with Covid therefore accounting for just 2.7 per cent, or one in 37 of these fatalities.

People in the UK who test positive for Covid are required to self-isolate for at least five days, although the British government says it plans to lift that requirement for England this week.

Both the Queen's eldest son Prince Charles, 73, and her 74-year-old daughter-in-law Camilla, Duchess of Cornwall contracted Covid-19 earlier this month. Charles has since returned to work. There are also thought to be several recent virus cases among staff at Windsor Castle, where the Queen is staying.

The Queen has a busy schedule over the next few months of her Platinum Jubilee year, and is scheduled to attend in-person public engagements in the coming weeks, including a diplomatic reception at Windsor on March 2 and the Commonwealth Service at Westminster Abbey on March 14.

On March 29, she has a remembrance service at Westminster Abbey for her husband Prince Philip, who died in April 2021 at 99.

Public celebrations of the Platinum Jubilee are scheduled over a long weekend June 2-5, with festivities including a military parade, a day of horse racing and neighbourhood parties.

- With AP