Will fine weather kill the virus and can my shopping be infected?

Q Will this warm weather we’ve been having help to destroy the virus?

A In February, President Donald Trump told an election rally crowd: ‘The virus… looks like by April, you know in theory, when it gets a little warmer it miraculously goes away. I hope that’s true.’

Britain’s Health Secretary, Matt Hancock, also told reporters at the time that coronaviruses are less transmissible during spring and summer.

But Professor Trudie Lang, a public health expert at the University of Oxford said earlier this month: ‘We absolutely don’t know that.’

Although some viruses are affected by hot weather, it is simply too early to tell how warm weather will impact the spread of Covid-19.

Another reason why some diseases flourish during colder months is because people spend a lot of time indoors and in crowded, poorly ventilated public places.

But the World Health Organisation have stated that Covid-19 ‘can be transmitted in ALL AREAS, including areas with hot and humid weather’.

Willem van Schaik, Professor of Microbiology and Infection at the University of Birmingham, says: ‘Data from Singapore – which is very close to the equator and which has a much warmer climate than the UK – suggests the virus can easily spread there too and can only be stopped by aggressive interventions, such as widespread testing and quarantining. So I am not hopeful that warmer weather will make much of a difference.’

Q Is there a risk of the virus being on the packaging of my food delivery?

A Ordering a grocery delivery is certainly a better option than going to a supermarket – but it’s not risk-free. If the delivery driver or shop worker who collected your order has contaminated hands, the virus could transfer on to the packaging of your food.

But coronavirus does not replicate outside the body, so by the time your food is delivered, it is likely to have become less infectious – so don’t worry too much.

Professor Sally Bloomfield, honorary professor at the London School of Hygiene and Tropical Medicine, says: ‘If you want to take further precautions then place all the items in the cupboard or fridge, where any residual viral infectivity will further decrease before you handle it again – and then wash your hands thoroughly.’

Supermarkets, in contrast, are hot-spots for transmission.

Even if they aren’t crowded, infected people could have touched items and put them back on the shelves, and contaminated other surfaces including checkout belts and card machines.

If you can’t get a home delivery slot, the usual advice applies: don’t touch your face while at the supermarket – as this could mean you become infected with the virus – and wash your hands as soon as you can afterwards.

Q I think I’ve already had the virus. Surely, I’ll be immune, and not able to spread it now?

A As many as half of the UK population could already have been infected with the new coronavirus, according to a scientific paper published last week by researchers at the University of Oxford.

This is far more than previously estimated. So could this mean lots of people are now immune to the disease?

Experts have warned the study should be treated with caution. While it is true that some people infected with Covid-19 appear to show no symptoms, there is currently no solid evidence on just how many people in the UK have had it.

Unless you can get tested, there’s no way of definitely knowing, and while it is likely that you will become immune after having it, we still don’t know for sure.

‘Patients who have already had Covid-19 and have recovered completely will not be able to spread the virus,’ says Prof van Schaik.

‘They will have built up some immunity to the virus, but one of the big unknowns is how much that will protect against reinfection.’

Dr Rossman adds: ‘Until we know for certain, it is safer to assume that you are not immune and can still be infected.’