The state of a person’s health before they become infected with Covid-19 appears to play a “crucial role” in determining how well they recover, global health leaders have said.

The World Health Organisation (WHO) said people in lockdown should try to maintain a healthy lifestyle.

The European branch of the WHO said older people with high blood pressure, diabetes or heart disease have a significantly increased risk of death from Covid-19.

It urged people to exercise, maintain a healthy diet and stop drinking and smoking.

People are also advised to reduce sitting time, getting up for at least three minutes every hour, to use household chores to be active, and aim for a daily goal such as 30 minutes of activity.

Online classes, strolls in the park and dancing to music could also help, the WHO said.

It said older people in general are at “significant risk of disease”, but those who have aged healthily are less at risk, highlighting how some centenarians have recovered from Covid-19.

It also warned that young people are not “invincible” from the disease.

Hans Henri Kluge, the WHO’s regional director for Europe, said the continent, along with the US, is at the epicentre of the pandemic.

In the last week, laboratory-confirmed cases of the disease have doubled, with 464,000 in Europe and 30,000 recorded deaths.

Dr Kluge said: “Older adults are at significantly increased risk of severer disease following infection from Covid-19.

“We know that over 95% of deaths occurred in people older than 60 years old. We also know from reports that eight out of 10 deaths occur in individuals with at least one underlying co-morbidity, particularly those with cardiovascular diseases, hypertension and diabetes, but also a range of underlying chronic conditions.

“All older people should be treated with respect and dignity during these times. Remember we leave no one behind.”

But he added that age is not the only risk factor, adding: “The very notion that Covid-19 only affects older people is factually wrong.

“On a positive note, there are reports of people over the age of 100 who were admitted to hospital for Covid-19 and have now since made a complete recovery.

“It is becoming clear that the healthier you were before the pandemic plays a crucial role. People who age healthily are less at risk.

“For those in self quarantine or working from home, it is important to maintain a healthy lifestyle with good nutrition, physical activity and staying away from tobacco and alcohol.”

It comes as the charity We Are With You – formerly Addaction – warned that increased social isolation could lead to a surge in harmful drinking.

Laura Bunt, acting chief executive at the charity, said: “These are really difficult times for everyone.

“Our experience of working with people to reduce the amount of alcohol they drink shows that social isolation is a big factor in why people may drink more heavily.

“Coupled with the huge anxiety of living through a pandemic, this means we could see a big rise in people drinking more alcohol at home.

“Harmful drinking can impact people’s physical and mental health.”