Fever - Fever in Thailand
A fever occurs when your temperature rises above its normal range. What's normal for you may be a little higher or lower than the average temperature of 37 C. That's why it's hard to say just what a fever is. But a "significant" fever is usually defined as an oral or ear temperature of 38 C or a rectal temperature of 39 C. If you're an adult, a fever may be uncomfortable, but it usually isn't dangerous unless it rises above 39 C. For very young children and infants, however, even slightly elevated temperatures may indicate a serious infection. In newborns, a subnormal temperature - rather than a fever - may be a sign of serious illness.
When you or your children aren't feeling well, one of the first things you may do is check for a fever. Although a fever isn't an illness itself, it's usually a sign that something's going on in your body. Yet fevers aren't necessarily bad. In fact, they seem to play a key role in helping your body fight off a number of bacterial and viral infections.
Because a fever can occur with many different conditions, other signs and symptoms can often help identify the cause. For example, nausea and vomiting with a fever may mean gastroenteritis. A fever in addition to a cough that produces thick, yellow or green phlegm might be pneumonia.
If you don't know why you have a fever, it's best not to try to lower your temperature. This may only mask your symptoms and make it harder to determine the cause. In addition, some experts think that aggressively treating all fevers actually interferes with your body's immune response. That's because the viruses that cause colds and other respiratory infections thrive at cool temperatures. By producing a low-grade fever your body may actually be helping eliminate the virus. What's more, most fevers go away in a relatively short time - usually within a few days.
Signs and symptoms
Depending on what's causing your fever, your signs and symptoms may include:
Very high fevers, between 39 C and 41 C, may cause hallucinations, confusion, irritability and even convulsions.
Approximately four percent of children under age 5 experience fever-induced seizures (febrile seizures). The signs of febrile seizures, which occur when a child's temperature rises or falls rapidly, include a brief loss of consciousness and convulsions. Although these seizures can be extremely alarming, most children don't experience any lasting effects. Febrile seizures are often triggered by a fever from a common childhood illness such as roseola, a viral infection that causes a high fever, swollen glands and a rash.
Even when you're well, your body temperature varies throughout the day — it's lower in the morning and higher in the late afternoon and evening. In fact, your normal temperature can range from about 36 C to 37 C. Although most people consider 36.5 C a healthy body temperature, yours may vary by a degree or more.
Your body temperature is set by your hypothalamus, an area at the base of your brain that acts as a thermostat for your whole system. When something's wrong, your normal temperature is simply set a few points higher. The new set-point, for example, may be 38.8 C instead of 36 C to 37 C.
When a fever starts and your body tries to elevate its temperature, you feel chilly and may shiver to generate heat. At this point, you probably wrap yourself in your thickest blanket and turn up the heating pad. But eventually, as your body reaches its new set-point, you likely feel hot. And when your temperature finally begins to return to normal, you may sweat profusely, which is your body's way of dissipating the excess heat.
A fever usually means your body is responding to a viral or bacterial infection. Sometimes heat exhaustion or an extreme sunburn or certain inflammatory conditions such as temporal arteritis — inflammation of an artery in your head — may cause fever as well. Some medications such as antibiotics and drugs used to treat hypertension or seizures may do the same. In rare instances, a malignant tumor or some forms of kidney cancer may cause a fever.
When to seek medical advice
Fevers by themselves may not be a cause for alarm — or a reason to call a doctor. Yet there are some circumstances when you should seek medical advice for your baby, your child or yourself.