When the hot weather comes back, people die from it, especially old and young people.
A small increase in a person’s core body temperature (hyperthermia) is usually referred to as 'Heat Stress' or 'Heat Exhaustion', which is usually not too serious. However, if this increase in temperature continues then people are at risk of 'Heat Stroke' which is a medical emergency.
Often, a combination of a warm environment (such as the current heat wave) and too much insulation is the cause. This can be further exacerbated by factors such as exercise or an underlying illness. When combined with dehydration, heat illness can quickly become fatal.
Babies and young children are particularly at risk, and problems often occur during the night, when clothing and bedding have not been appropriately adjusted. If you're not sure what to put them in, it's always better to have less insulation rather than more. Hot babies can have seizures that may put them at risk of further harm or even death.
Someone with heat exhaustion will be flushed, hot, sweating and may have cramps or feel sick. They might also be feeling lethargic. Simply cooling the person down by putting them in a cool environment, stripping off any clothing and giving them plenty to drink should fix the problem.
If the person is hot and dry then they are dehydrated as well. This means that their body is no longer able to cool itself down and is likely to lead to a rapid increase in temperature. The person is also likely to have a fast breathing rate or pulse, a seizure, become confused, unconscious or floppy. This is Heat Stroke and they need help fast.
If you suspect someone has Heat Stroke, call 999 and cool them rapidly, but do not put them in a cold bath or shower. Strip them off and run their wrists under cold water, or put cold packs (wrapped in a tea towel) in their armpits and groin. Rehydrate them with frequent sips of cold water. If they're unconscious you'll need to manage their airway. Use a head-tilt chin-lift manoeuvre or put them in the recovery position and continue to cool them whilst waiting for the Ambulance.
As always, prevention is better than cure. Don't stay in the sun for too long and make sure everyone is drinking plenty - especially babies and older people.