Hypothermia occurs when a person's body temperaturedrops below 35C (95F). Normal body temperature is around 37C (98.6F).
Hypothermia can quickly become life threatening and should be treated as a medical emergency.
It's usually caused bybeing in a cold environment and can be triggered by a combination of factors, such as being outdoors in cold conditions for a long time, living in a poorly heatedhouse orfalling into cold water.
People who areunable to move around to generate heat, such as the elderly or those who are ill, are at particular risk of developing hypothermia.
During 2013-14, more than 1,600 people seen in hospital were diagnosed with hypothermia. Just over 70% of these cases were people over 60 years of age.
Babies are also more prone to developing hypothermia because their bodies' ability to regulate temperature isn't fully developed.
But it's not just babies and elderly or ill people who develop hypothermia. Anyone who spends long periods outside during the winter without wearing appropriate warm clothing can also be at risk, particularly after drinking large amounts of alcohol.
For example,in recent years there have been several cases of young people developing hypothermia after getting drunk on a night out and failing to find theirway home, wearing onlylight clothes.
People who spend a considerable amount of time outside in cold weather conditions, such as climbers and skiers, are also at increased risk of getting hypothermia, particularly if they don't wear suitable clothing.
Initialsymptoms include shivering, tiredness, fast breathing and cold or pale skin.
As the temperature drops, shivering becomes more violent, although it will stop completely if the hypothermia gets worse. Theperson is likely to become delirious andstruggle to breathe or move. They may lose consciousness.
Babies with hypothermia may look healthy, but their skin will feel cold. They may also be limp, unusually quiet and refuse to feed.
In this case,dial 999 immediately to request an ambulance.
While waiting for medical help, it's important to try to prevent further heat loss and gently warm the person. Follow these steps:
If the person is unconscious, not breathing and you can't detect a pulse in their neckafter60 seconds,cardiopulmonary resuscitation (CPR) should be given if you know how to do it. Once CPR is started, it should be continued without any breaks until medical assistance arrives.
After the person is transferred to hospital, advanced medical treatments, such as removing blood from the body, heating it and returning it to the body, can be used to warm the person up.
Simple measures can help, such as wearing appropriate warm clothing in cold weather and ensuring that children are well wrapped up when they go outside.
Whenever possible, keep an eye on elderly or ill neighbours and relatives to ensure that their home is warm during cold weather. The government offers aWinter Fuel Paymentfor older people living alone who are vulnerable to hypothermia.
Learn how to spot the signs of hypothermia, who's at risk, when to seek medical help, and how to prevent getting hypothermia.
The symptoms of hypothermia can vary depending on how low your body temperature has become. It can often cause confusion, poor judgement and changes in behaviour.
Hypothermia is caused by getting too cold, as the body loses more heat than it can generate and the body temperature drops below 35C (95F).
Learn about how hypothermia is treated, including treatment in the home, what to avoid, and when to seek medical advice.
Read about simple measures you can take to prevent you, your child or elderly relatives getting hypothermia, such as wearing appropriate clothing and heating your home.