So, first off- what causes a fever? A fever is a rise in internal body temperature usually triggered by the immune system as a response to bacterial or viral infection. This is different than hyperthermia- which is caused by the body's inability to regulate its temperature when faced with high external temperatures in the environment (like a heat wave in summer).
In a healthy adult, most fevers aren't dangerous. Problematic fevers for normal adults and children are anything over 102 degrees Fahrenheit, or any fever that lasts for more than three days. For children under two, a fever for more than one day is a good time to call the doctor. Serious fevers for babies three months old or younger start much lower, though: if a three month old or younger baby has a temperature of 100 degrees Fahrenheit or higher, it should see a doctor.
Other important signs to look for that indicate that someone should be taken to the doctor include: severe headaches, stiff neck with pain when you bend your head forward, mental confusion, or extreme listlessness, irritability or other extreme emotional states. If diarrhea or vomiting is present along with the fever, the person should be watched carefully to make sure they are getting enough fluids so that dehydration doesn't set in.
Now, what about thermometers? The push over the past several years to phase out mercury thermometers means that the most of the available thermometer options are going to be digital, battery operated models. This is fine when you live close to the store and can run out for another one- because it seems like the battery always goes dead just when you need it- but there are two other options that should be considered as back up. One is a solar powered model, which would be somewhat better than a regular digital. Just be aware that, eventually, that battery will no longer be able to hold a charge, either. The best option to consider is probably a clinical grade, mercury- free glass thermometer. No batteries to fail. They are glass, though- which means care should be taken not to drop them and to store them in their case. These use a non-toxic liquid in the bulb as a substitute for the mercury found in older models. These can be found by reputable manufacturers online for less than ten dollars each, so cost wise they are even competitive with digital thermometers.
Next week, we will take a look at how to help someone with a fever feel more comfortable, and also begin looking at traditional herbal support for fevers.
For more info to help you brush up on your fever first aid, check out the mayo clinic website:
Fever First Aid
All About Fevers