A myth that Covid-19 cannot live or be transmitted in hot or humid regions has been circulating on WhatsApp and other social media channels. 

From the evidence collected so far, the Covid-19 virus can be transmitted in all areas regardless of climate. The best way to protect yourself against Covid-19 is by frequently cleaning your hands with soap for at least 20 seconds each time and avoiding infection by not touching your eyes, face or mouth.

However, hot weather and humidity have been found to have an impact on coronaviruses:

  • Human coronaviruses can remain infectious on hard surfaces at room temperature for up to 9 days. At a temperature of 30°C or more, the virus cannot last on surfaces for as long.
  • A recent study found that high temperature and high humidity reduce the transmission of COVID-19. This is perhaps because some coronaviruses have an ‘envelope’ that protects viral particles when dispersing. In warm temperatures, this layer can dry out and stop working faster. 
  • Humidity is how much moisture is in the air. High humidity means viral droplets keep their moisture content so droplets are heavier and less able to remain in the air – and so spread between people less easily. 

However the spread of a virus depends on more than its ability to survive in the environment. Changing human behaviour plays a key role in altering infection rates. Therefore, social distancing practices, self-isolation if you suspect you have symptoms and following local and WHO hygiene guidelines are very important.