The largest outbreaks of Covid 19 seem to suggest that the virus has a preference for cool and dry conditions. Could this mean that that the virus might start to die off in the UK in the summer?
Dr William Bird, the founder of the Beat the Street game, works as an out-of-hours doctor at the Royal Berkshire Hospital in Reading and regularly treats patients showing symptoms of Covid 19.He was head of the Health Forecasting Unit at the Met Office which predicted the spread of viruses.
He says: “Covid is a new disease, so we’re still learning about how it spreads and in what circumstances it thrives. However, looking at the data we have so far, it has been defined as a winter virus so doesn’t cope well in warmer weather, which is possibly one reason why countries such as Australia and New Zealand have got through this crisis with fewer deaths.”
“We’re enjoying some warmer weather at the moment and it will be interesting to see if this helps to curtail the spread of the virus. We’ve seen similar viruses, such as seasonal flu, struggle to survive in hotter temperatures, so if it does follow this pattern, then hopefully we could see a downward turn in the transmissibility of Coronavirus in the next couple of months.”
The virus is highly contagious and as such, has been passed from person to person while the population has been huddled indoors. As we know, it also survives on certain surfaces for up to 72 hours. When people spend more time outdoors in gardens as the weather gets warmer, the virus should find it harder to jump from one person to another, plus our bodies will be creating more vitamin D in the sunlight. Cold air dry air being breathed through the nose dries out the mucus membranes reducing the ability to fight the virus which is more active in these conditions.
Another strain of the Coronavirus was the cause of the SARS outbreak in 2003 which was also found to survive in cool, dry conditions. This also remained infectious on hard surfaces at temperatures ranging from 22-25C and with a relative humidity of 40–50%. The higher the temperature and humidity, the shorter the virus survived.
Dr Bird continues: “Research shows that Covid 19 is destroyed by UV light and wind dilutes the concentration of the airborne virus. Warmer weather seems to affect the stability of the virus outside the body. It doesn’t like rain either as it gets washed away and there’s no air pollution particles dust or pollen to hold onto. The virus does seem to like typically winter weather such as fog as its droplets can be suspended in the air and there is no wind or UV light with lower temperatures.
“We are hopeful then, that the pandemic should start to trail as the summer ends. We’re all keeping an eye on Australia’s figures as it approaches its winter as their R value (rate of infection to others) has just gone above “1.0” for the first time in six weeks.”
While we wait to see what happens, please continue to stay active, perhaps using your daily hour of exercise to get outdoors for a walk, or by doing exercises in the house.