Fiver is one of the most common symptoms of disorders. So what is a fever? It is a condition when our body temperature rises above the normal of 98.6 F (37 C). Causes of fever is not fully understood yet. There could be hundreds of reasons for the rise in body temperature and thus interpreting it may not be that easy. Fortunately, in most of the cases understanding the causes is not difficult. It is considered to be a defensive reaction in humans. In adults, it is rarely a reason for concern. However, things are different in case of children and young ones, where it may be due to some severe infection.

What is a fever?

What is a fever, and its underlying mechanism is not fully understood yet, but it is the defensive reaction in most cases, and infections are the most common cause of it. During this defensive reaction, our body initiates an immune response to the disease. This immune response also releases the so-called pyrogens into the blood. These pyrogens reach the brain and change the way hypothalamus in brain controls temperature. This process forces the hypothalamus to increase the body temperature. This increase in body temperature is helpful in fighting infections, it stimulates the immune system, and helps in the production of antibodies.

While approaching the question what is a fever, not all kind of temperature rise is a defensive response. Heat stroke is an exception. It is a condition when hypothalamus loses the ability to control body temperature due to extreme heat. Thus it has to be suppressed immediately and unconditionally.

The approach to rise in temperature would depend on the cause. Most mild temperatures are not a threat to the health, but extremely high body temperatures may be dangerous for body and brain.

Symptoms of fever

Not all rise in temperature are the same, type of it can help a doctor in the diagnosis of the disease. It differs in severity, fluctuations, continuity, and presence of other symptoms. Some of the common symptoms associated with it are:

1. Chills and shivering- they happen mostly when the temperature is rising, as the body tries to increase its temperature due to the effect of pyrogens and instructions of the hypothalamus.
2. Sweating- as temperature increases most would sweat. Sweating may be more intensive when temperature is decreasing, as it is a way of cooling the body.
3. Headaches- our brain is susceptible to changes in temperature. Hence, high body temperature not only causes headaches, but it may also make difficult for our mind to think or operate.
4. Muscle aches- happen due to various reasons, like toxicity, their role in elevating body temperature.
5. Loss of appetite
6. Irritability
7. Dehydration- as our body temperature rises, we lose more and more of fluids.
8. General weakness or malaise

In children it may also cause seizures, they happen as their nervous system is more sensitive to the temperature changes. Seizures may also occur due to electrolytic disturbances in young ones.

Causes of fever

There are 100s of reasons or causes of fever, and it not only helps to fight the diseases but may also help a doctor in diagnosis. Further, the temperature may also tell about the severity of the disease. It is the reason that suppressing the temperature rise without consulting a doctor is not recommended, as it may mask one of the vital symptoms.

Common causes of fever are:

1. Various viral infection
2. Bacterial infections
3. Heat stroke
4. Non-infectious inflammatory diseases like lupus, rheumatoid arthritis
5. Different types of cancers
6. In young children, vaccination may raise body temperature for few days

Rise in temperature prolongs and not very high in non-infectious cases, in some cases, it may only rise in the evenings. In infections, it is more acute and would not usually last more than a week, though there are exceptions.

In tropical countries, it may occur due to diseases like malaria, typhus, and various parasitic infections.

Unfortunately, it is not always possible to identify the causes of fever; it is something doctors call unknown origin, though such cases are rare.

When to see a doctor?

The approach towards fever would differ in adults and children. In adults, if it is an isolated thing, without other severe symptoms than it is better to wait few days for it to subside. However, in young ones, understanding the cause is difficult, and home treatment may be dangerous. Thus it is a reason to call or visit a doctor, particularly if:

1. A child is below three months of age and has elevated temperature during the measurement with a home thermometer.
2. The child is less than six months and has a temperature of 101°F or higher.
3. The child is above six months and has a temperature of 103°F or higher.
4. Child of any age with a temperature of 104°F or higher.
5. Fever that would not subside within 48 hours and there are other symptoms like a sore throat or severe diarrhea, pain while urinating, seizures.
6. Even if it is not very high, but the child is too lethargic and refuses eating or even drinking and has difficulty in breathing.

In adults, it is better to see a doctor if it is above 103°F. Especially if there is neck stiffness, severe headaches, mental confusion, difficulty in breathing, abdominal pain, or convulsions.

How to manage fever at home?

It is important to monitor your body temperature using a digital thermometer. If it is not severe and symptoms are mild, you can manage it at home itself. Most researchers these days agree that suppressing a mild one with drugs may not be a good idea. Thus in temperature, it is vital to stay hydrated, take plenty of rest, though a moderate walk is also not bad (especially in a seasonal thing). If a person is feeling too uncomfortable, aspirin or acetaminophen can be taken to relieve temperature and pain. Vital is not to abuse these over-the-counter drugs. If it lasts longer than expected and medications do not help enough, it is always wise to seek medical attention. Hence understanding what is a fever and causes of fever are the prime things in managing it at home.