COVID-19: Avoiding heatstroke

Many people who are at risk of harm from heat can also be a risk of severe illness due to COVID-19. These people will often be ‘shielding’ or self-isolating from others and will spend more time at home. Public Health England state: “It is especially important that you know what actions to take to keep yourself and others safe from high temperatures…we still have much to learn about how COVID-19 affects the body but both heat and COVID-19 infections put a strain on the heart, lungs and the kidneys, and are linked with inflammation in the body”

Staying cool at home
  • Shade or cover windows exposed to direct sunlight
  • Open windows when the air feels cooler outside than inside – this will help to get the air flowing through your home
  • Turn off the central heating, lights and any electrical equipment that are not in use
  • Use electric fans (if you have one) – always remember not to aim the fan directly at yourself (only use electric fans when you or your household members do not have any symptoms of COVID-19 as this will limit the transmission).
  • Check that fridges and freezers are working properly
Stay cool, keep well
  • Drink plenty of fluids and avoid excess alcohol
  • Increase fluid intake as more fluid is required when the weather is hot as it replaces the fluids lost through sweating
  • It is essential to keep hydrated if you are suffering from symptoms of COVID-19
  • Look out for signs of dehydration
Slow down when it is hot

Lots of activity can make anyone prone to heat-related illnesses, no matter how fit and healthy you are. You should avoid extreme physical excretion – particularly during the hottest part of the day.

Cooler safer places

Ensure you go indoors or outdoors whichever is the coolest. It is important that you give your body a break from the heat. Don’t always assume you will be cooler in the house, it might be cooler outside in the shade.

Heat-related illnesses

The main causes of illness and death during a heatwave are respiratory and cardiovascular diseases. The list below highlights specific heat-related illnesses:

  • Heat Cramps – Caused by dehydration and loss of electrolytes, often following exercise
  • Heat Rash – Small, red, itchy papules
  • Heat Oedema – Mainly in the ankles, due to vasodilation and retention of fluid
  • Heat Syncope – Dizziness and fainting, due to dehydration, vasodilation, cardiovascular disease and certain medications
  • Heat Exhaustion – The most common illness. It occurs as a result of water or sodium depletion, with non-specific features of malaise, vomiting and circulatory collapse, and is present when the core temperature is between 37-40 degrees – left untreated, heat exhaustion may evolve into heatstroke.
  • Heatstroke – Can become a point of no return whereby the body’s thermoregulation mechanism fails. This leads to a medical emergency, with symptoms of confusion, disorientation, convulsions, unconsciousness, hot dry skin, and core body temperature exceeding 40 degrees for between 45 minutes and eight hours. It can result in cell death, organ failure, brain damage or death. Heatstroke can be either classical or exertional.


  • Heatwave Plan for England: Supporting vulnerable people before and during a heatwave. NHS England (2015)
  • Heatwave plan for Wales: A framework or preparedness and response. Welsh Government (2012)
  • Heatwave leaflet