Masks? They’re a bit like a hankie... not complicated

coughs, splutters or breathes out, stopping them from reaching others.

Some evidence suggests masks don’t really block virus particles which may hang, suspended in the air rather than falling to the floor or landing on surfaces like droplets.

There is also some evidence that touching the face coverings increases infection risk, although again studies are small and were carried out in medical settings where more viral particles are around.

But Prof Greenhalgh warned against ‘overthinking’ mask use – something is better than nothing. ‘Think of it like a hankie, but one that’s attached to your face,’ she said.

‘Your mother probably taught you how to use one of those at some point during childhood. It’s not any more complicated than that.’

Prof Paul Hunter says: ‘The problem is the evidence [on masks] from the studies is mixed. Even so, there’s certainly enough data to suggest, if worn correctly, and if enough of us wear them, they can help keep levels of transmission down.’

A mask should cover the mouth and nose, and two layers of fabric is ideal, although the World Health Organisation says three. They should be comfortable, so you don’t remove them, and sit snugly against the sides of your face.

Cloth coverings can be washed with normal laundry, or just rinsed by hand with soapy water.

And if you need to pull it down to scratch your nose, is there any point in putting it back on?

‘Yes. Wearing it for 20 minutes on the train, for instance, will offer twice the protection to others than wearing it for just ten minutes.’

AT THE start of the pandemic, we were told it was older people and those with pre-existing medical problems that were most at risk of getting seriously ill or dying from the virus. Has anything changed?

YES, and no. At the beginning, experts relied on a study of 44,000 Chinese patients to determine which groups were most vulnerable. Primarily, those with any underlying illness and elderly were the patients who were most severely ill, or died.

Now that we have a raft of extra research – involving millions of patients across the world – our understanding has changed. For instance, patients with some types of cancer, and those receiving drug treatment that suppresses the immune system have been shown to be at no increased risk of dying. High blood pressure, on its own, also is no longer thought to make a person more at risk from Covid-19.

Pregnant women were also given mixed messages, with early research showing they were at no increased risk of infection, or serious illness.

But recent studies suggest mothers-to-be who catch the illness are more likely to miscarry. Dr David Strain, a senior lecturer in diabetes and vascular health at the University of Exeter said:

‘The virus can trigger small blood clots and this has been linked to miscarriage.’

Being obese triples the risk of dying from Covid-19 – something that wasn’t known at the start.

Initially, it wasn’t clear whether weight alone was the reason, or just that overweight people often also suffered other conditions like heart disease, but now a clearer picture has emerged.

Experts think excess fat surrounding the lungs can further strain the respiratory system, worsening breathlessness and restricting the supply of oxygen. Chronic illness, however, remains one of the biggest predictors of hospitalisation, and death. Office For National Statistics data shows that 90 per cent of Covid-19 deaths have been in those with long-term health conditions including type 2 diabetes, HIV, and heart, kidney and respiratory disease.

And the most predominant risk factor remains unchanged: age. According to Sir David Spiegelhalter, professor at the Winton Centre for Risk and Evidence

Communication at Cambridge University, the risk associated with being over the age of 50 is the biggest – over and above other known risk factors, including underlying illness. ‘Your risk of dying from coronavirus once you’ve caught it increases 12 to 13 per cent for every year you’re alive,’ says Prof Spiegelhalter.

‘An 80-year-old is at 1,000 times the risk of dying from Covid-19, compared to a 20-year-old.’

By now, it’s clear people over the age of 50 are at most risk of complications. Men, as was first observed back in February, are also twice as likely to get ill. Experts believe this is due to sex differences in immunity.

What about black and Asian people?

BLACK men have triple the risk of dying from Covid-19, compared to white men the same age. And people of South Asian heritage are roughly twice as likely to die, compared to their white counterparts, according to the most recent figures.

In June, a Public Health England report revealed that a staggering 90 per cent of doctors who have died from the virus came from black, Asian and other minority backgrounds.

It was suggested that genetic factors may be to blame, but the recent Public Health England report into the racial disparities between Covid-19 victims found that social and environmental factors are the more likely explanation.

Adrian Martineau, professor of respiratory infection at Queen Mary University London, who is leading a major piece of research into risk factors, said: ‘Exposure to the virus is the biggest risk factor across the board, according to our data of 10,000 participants. Black and Asian groups are overrepresented in jobs that automatically put them at higher risk – such as in the public sector working as health workers, carers, bus drivers or cleaners.’

These groups are also more likely to live in densely populated towns and cities, and in homes with multiple generations, increasing potential exposure to the virus.