Viral Fever

A viral fever is a higher-than-average body temperature that a virus causes. Often, a person will experience symptoms that may include a runny nose, coughing, nausea, fatigue, and body aches.

Causes of Viral Fever #

• There are many potential causes of viral illness, which may include cold and flu viruses.

• Sometimes, a bacterial illness follows a viral one.

• This can make it difficult to tell the difference between the two and determine when a person may benefit from taking antibiotics.

• Fevers without any other apparent underlying illness can be especially common in young children.

• In a study of 75 children with a fever but no other signs of bacterial infection, the results of which appeared in the journal Pediatrics, an estimated 76 percent had one or more viruses in their system.

• The most common viruses present were the adenovirus, human herpesvirus 6, enterovirus, and parechovirus.

• The paper estimated that less than 1 percent of fever-related illnesses with no appearance of a clear source in children under 3 were due to bacterial infections.

Symptoms of Viral Fever #

• A fever is the body’s natural reaction to exposure to disease-causing pathogens, such as viruses and bacteria.

• The body’s increase in temperature can destroy the proteins in these pathogens to keep them from multiplying.

• Also, fever is an inflammatory response to the illness in the body.

• The definition of a fever depends on a person’s age and where the temperature reading originates from.

According to the Seattle Children’s Hospital, the following are indicators of a fever in children:

• Rectal, ear, or forehead: The temperature is higher than 100.4°F (38.0°C).

• Oral: The temperature is higher than 100°F (37.8°C).

• Under the armpit: The temperature is higher than 99°F (37.2°C).

• The definition of fever can vary in adults.

• However, many doctors will consider a body temperature reading using an oral thermometer that is higher than 100°F (37.8°C) as a fever.

A viral fever can cause a person to feel fatigued, irritable, and achy. Additional symptoms may vary based on the virus causing the underlying illness.

For example, the roseola virus causes a fever for 2–3 days in children, followed by a rash that starts about 12–24 hours after the fever subsides.

Diagnosis of Viral Fever #

• A doctor will take a person’s health history and ask questions about their symptoms when diagnosing a potential viral fever.

• Examples of these questions may include when a person first noticed the symptoms and what makes these symptoms worse or better.

• A doctor may order tests to identify the presence of viruses in a person’s blood, sputum, or urine.

• For example, a rapid influenza diagnostic test involves taking cell samples from the back of the throat and testing them for the presence of influenza A or B proteins.

• Not all tests for viral illnesses are available so quickly, however.

• In fact, some may require laboratory analysis to identify the specific virus.

• However, it is not always necessary to send tests to the laboratory to diagnose a viral fever.

• A doctor may take into account a person’s symptoms to make this diagnosis.

Treatment of Viral Fever #

For lower-grade fevers, treatments may include the following:

• Taking OTC medications: Ibuprofen and acetaminophen are both OTC medications that can relieve fever. Aspirin can also do this, but people under 18 should not take aspirin due to the risks of a condition called Reye’s syndrome. Antibiotics will not treat a fever due to viral illness.

• Taking lukewarm baths: These can also soothe a feverish body.

• Drinking cooled fluids: Sipping on cool water or electrolyte-containing solutions can help cool body temperatures and prevent dehydration related to illness.

If a person has a fever for longer than 3 days, or they have a temperature higher than 103°F (39.4°C) in adults, 102°F (38.9°C) in children, or 100.4°F (38°C) in infants, they should seek medical attention.

Body temperatures higher than this can cause seizures, hallucinations, and confusion, and they are symptoms of a more serious illness.