The Lamen


by | Jan 20, 2023

If your body temperature rises above the normal human range of 98-100°F (36–37°C), you are probably experiencing a fever (including a viral fever). Fevers are a sign of your body’s immune system at work, fighting off an infection.

Fevers can be caused by a number of pathogens. However, when a virus is the underlying cause of your fever, we refer to it as viral fever.

Viral fever is most common during monsoons and the winter, caused by small infectious agents that are highly contagious.

Viruses that cause the common cold or the flu are generally the cause. However, serious cases of viral infections like dengue fever or yellow fever might also cause high temperatures.

Viral fevers generally go away with simple remedies, while more serious cases might require intensive care. Continue reading this article to learn about the common symptoms of viral fever, some home remedies, treatment, and when you should seek a doctor.

Symptoms of viral fever

Rubber bands on braces are typically worn to correct misalignments.

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In the majority of cases, a viral fever can range from 99°F to over 103°F (37°C to over 39°C) in temperature, depending on the causative virus. These numbers can be different for kids, where a fever is indicated by:

  • higher than 99.5°F (37.5°C) when measured orally
  • a temperature higher than 100.4°F (38°C) when measured rectally
  • higher than 99°F (37.2°C) when measured under the arm

The general symptoms of viral fever are similar to other types of fever, which include:

  • chills and shivering
  • runny nose
  • sweating
  • headaches
  • irritability
  • body aches
  • fatigue
  • dehydration
  • loss of appetite
  • weakness

If a baby has a fever, they may show the following signs:

  • flushed cheeks
  • sweating intermittently
  • feeling hot to the touch
  • irritability

In most cases, these symptoms last only for a few days. However, a high or persistent fever may indicate some underlying health conditions requiring medication attention.

Is it a viral fever?

It can be difficult for you to tell if you have a viral fever or a bacterial infection because many of their symptoms are the same.

A fever is typically characterized by the elevation of body temperature above the normal range of around 98.6°F (37°C). Other common symptoms include chills, fatigue, sweating, and muscle aches.

To tell whether the fever is viral or bacterial, a doctor typically takes nasal or throat samples. These samples are then grown in a culture and examined to diagnose your fever.

Do you have a viral fever or COVID-19?

The coronavirus disease (COVID-19) is an infectious disease caused by the SARS-CoV-2 virus. In most mild cases of the disease, people experience moderate respiratory illness, coupled with a fever. In case you experience a dry cough with a fever, you may have COVID-19.

The common symptoms of coronavirus include:

  • chills
  • cough
  • shortness of breath
  • fatigue
  • body or muscle pains
  • loss of taste or smell
  • diarrhea

In case you experience the above symptoms, you should consider getting tested for COVID-19. In case you have tested positive, you should take the necessary precautions to avoid transmission of the disease.

According to the Centers for Disease Control and Prevention (CDC), people with the disease should practice isolation, masking, and avoiding contact with other people, especially those who are at a high risk of getting very sick.

In case a person experiences severe pain in the chest, difficulty breathing, nausea, or severe headaches, they should seek immediate medical care.

What causes a viral fever?

As the name suggests, viral fever is caused by infection from a virus. Viruses are very small (as small as 20 nanometers) infectious agents made up of a piece of genetic material – either DNA or RNA, enclosed in a protein coat.

While not all viral diseases are contagious, the most common ones like the common cold, flu, and herpes virus can be transmitted from one person to another.

When a virus enters and multiplies within your body, it generates an immune response which causes an increase in your body’s temperature.

There are several ways in which you can get infected by a virus, including:

  • Respiratory droplets. When an infected person sneezes, coughs or simply breathes, they can also exhale droplets that contain the virus. If you inhale these droplets, you can easily catch the virus. Such infections include the common cold and the flu.
  • Fomites and ingestion. Foods, drinks, utensils, sheets, and other things that an infected person uses can be contaminated by viruses. If you use or eat them, there is a chance that you can catch the infection, such as the norovirus and rotavirus.
  • Bodily fluids. Exchange of bodily fluids with someone who has a viral infection during activities like sex, sharing needles and syringes, or the exchange of blood can also result in the transmission of infection. Sexually transmitted infections (STIs) commonly pass from one person to another through these means. Most common examples include herpes and AIDS.
  • Bites. Bites from insects and other animals which carry certain viruses can also result in an infection. The dengue virus is one such infection.

Fevers without any other apparent signs of some underlying illness can be common in young children. This does not mean, however, that something is wrong. Mild fevers are a sign of a healthy immune system, and children tend to have a slightly higher basal body temperature compared to adults.

A person’s body temperature also changes with exercise, stress, clothing, food, medications, or menstrual cycles in women, and it does not indicate anything wrong in such cases.


Besides an increase in your body temperature, a number of symptoms can infection. Telling the difference between a viral and bacterial infection can be hard, considering they display many similar symptoms.

In fact, a number of health conditions, such as pneumonia and diarrhea, can be caused by either bacteria or viruses.

The key difference between bacterial and viral infections is that while antibiotics are effective in curing a bacterial infection, they are ineffective against viruses.

To diagnose whether your infection is viral or bacterial, the doctor may:

  • ask about your symptoms and medical history
  • perform a physical exam
  • order blood tests or a chest X-ray
  • take nasal or throat samples for respiratory infections
  • may inquire about recent travel history

Additionally, if there’s a current epidemic of a particular disease, the doctor may factor in your recent travel history and whether you have the epidemic or pandemic in your area. The doctors generally use culture tests to rule out a bacterial infection.

How to take a temperature

A digital thermometer is the most convenient way to check your temperature. You should never use mercury thermometers, as they risk mercury poisoning due to exposure.

You should always take the following precautions when using a thermometer:

  • Read the instructions.
  • Wash your hands with soap before using the thermometer.
  • Clean the thermometer before and after each use, with rubbing alcohol, or with soap and lukewarm water.
  • Don’t use the same thermometer for oral and rectal temperatures.
  • Use function-specific thermometers, such as a digital ear thermometer to measure ear temperature.

Rectal temperatures are known to be the most accurate, while those done in the armpit are found the least accurate. When taken properly, oral and ear temperatures are also respectably accurate.

Taking an oral temperature

Oral thermometers are quick and easy to use, and pretty accurate when used correctly. Always make sure to rinse the thermometer with soap and water or clean it with rubbing alcohol before and after a reading.

  • If you have been eating, drinking, or exercising, wait 30 minutes to an hour before taking an oral temperature.
  • Hold the digital thermometer tip under the tongue for about 40 seconds, or until it makes a beeping noise.
  • The reading will continue to increase. You should hot the thermometer tip in the same spot.
  • Once the thermometer beeps, simply read the temperature.
  • For more accurate readings, you can take your temperature 3 times, and calculate the mean value by simply adding up all the temperatures and dividing them by 3 (T1+T2+T3/3 = Mean Body Temperature).

In addition, you should not take an oral temperature if the person just smoked, if they have a stuffy nose, or if they’re unconscious.

Taking an ear temperature

Digital ear thermometers also called tympanic thermometers, use an infrared ray to measure the temperature inside the ear canal.

  • Pull the top of the earlobe (the soft, fleshy part of your ear) upwards and back.
  • Carefully insert the tip of the thermometer into the ear canal. Make sure the sensor is pointed in the direction of the ear canal.
  • The thermometer should not feel uncomfortable or cause any pain in the ear.
  • Once inserted, turn the thermometer on and wait till it takes a reading.
  • Once complete, take the thermometer out and read the temperature.

While an ear thermometer can be a quick and easy way to measure temperature, it should not be used if a baby is three months old or younger. They can also be inaccurate if someone has too much earwax, or if they’re suffering from some ear infection.

Taking a rectal temperature

A rectal thermometer is the most accurate tool to check body temperature, especially in infants and children. To take a rectal temperature, you’ll need a digital rectal thermometer as well as a lubricant, like petroleum jelly.

Here are the steps to use one:

  • Put petroleum jelly on the end of the thermometer.
  • Lay the child on their stomach, spread their buttocks, or simply place them on their back and lift up their legs and knees.
  • Insert the tip of the thermometer about an inch into the anal canal, but no more.
  • Keep the thermometer in place for about a minute, or until it makes a beeping noise.
  • Remove the thermometer and read the temperature.

You should seek medical care if the rectal temperature is:

  • In babies under 3 months: 4°F (38°C) or higher
  • In children older than 3 months: 0°F (40°C) or higher

You should make sure that you don’t use a rectal thermometer for other body parts. Additionally, properly disinfect it with rubbing alcohol or an alcohol-based wipe before and after each use.

Home remedies for viral fever

In the majority of cases, viral fevers go away with rest and don’t require any specific treatment. You can, however, try the following home remedies to ease discomfort and even recover quicker.

  • Drink plenty of fluids. A viral fever elevates your body temperature, causing excessive sweating. If fact, a person can lose up to 1,000 grams of water by sweating (dermal loss). Therefore, you should as many fluids as you can to replenish the lost fluids. Adding electrolytes can to your drinks can be even more beneficial.
  • Rest as much as possible. A fever is a sign of your immune system going to work to fight off the infection. This can place a lot of additional load on your body. Therefore, you should avoid intense physical activity in times of extreme fever, and get at least eight hours of sleep.
  • Take a lukewarm bath or shower. Contrary to belief, a warm bath actually helps you lower your body temperature. The warm water increased blood flow to the skin while increasing heat loss from the body and lowering your core temperature. This not only relieves the fever but also helps with the circadian rhythm for a good night’s sleep.
  • Avoid caffeine and alcohol. Caffeine is known to have a mild diuretic effect, causing more urination, which can increase the risk of dehydration during a fever. Alcohol is known to have a similar diuretic effect.
  • Take OTC medication. Over-the-counter (OTC) medications are effective in temporarily relieving the symptoms of a fever. Common fever reducers include acetaminophen, aspirin, and ibuprofen. Always read the dosage and instructions on the package of medications, and do not give these medications to children without consulting with a doctor.

It is important for you to remember that a mild fever is a normal immune response, indicating that your body is fighting off an infection. It is usually of no concern and goes away on its own in about a week.

However, if you experience a high fever or a fever accompanied by other serious symptoms such as difficulty breathing, chest pain, or severe dehydration, you should seek a doctor.

Treatment and medication for viral fever

A viral fever is caused by a viral infection, and therefore cannot be treated with antibiotics. Treatment for viral fever usually involves relieving the symptoms to provide some relief.

Besides staying hydrated and getting plenty of rest, a doctor may advise you to take the following OTC fever reducers:

  • acetaminophen
  • ibuprofen
  • aspirin

It is important to follow the proper dosage instructions provided by the healthcare professional.

A doctor may also prescribe antiviral medication to treat a viral infection. It is important to remember that antiviral medication is ineffective against bacterial infections, and are generally prescribed only in case:

  • the patient shows severe symptoms
  • the infection may cause some complications
  • the infection is highly contagious

According to the Centers for Disease Control and Prevention (CDC), there are four FDA-approved antiviral drugs effective in treating the flu:

  • oseltamivir phosphate (Tamiflu)
  • zanamivir (Relenza)
  • peramivir (Rapivab)
  • baloxavir marboxil (Xofluza)

There are common side effects for various medications, and they may vary for different individuals. Commonly reported side effects of these medications to include nausea, vomiting, and diarrhea. They should therefore be taken under the supervision of a healthcare provider.

Complication and warning signs

While a fever is generally self-relieving, certain signs can be indicative of some serious underlying health problems.

If you are experiencing a fever of 103°F (39.5°C) or higher, it is best to seek medical care. If a child younger than 3 months old has a rectal temperature of 100.4°F (38°C) or higher, you should call the doctor.

In addition, if you experience any of the following signs, you should seek out a doctor immediately:

  • difficulty breathing
  • severe headache
  • a stiff neck or swollen lymph nodes
  • confusion or irritability
  • nausea or vomiting
  • chest pain
  • abdominal pains
  • diarrhea
  • the appearance of a rash
  • severe dehydration
  • seizures

If a fever in an adult is at 105.0°F (40.5°C) or higher and does not come down with treatment, it is a life-threatening situation and you should immediately call your healthcare provider.


A viral fever is caused by a viral infection, which can spread from an infected person by sneezing, breathing, or touching surfaces.

Here are some steps you can take to prevent a viral fever:

  • wash your hands with soap frequently
  • avoid close contact with some sick or displaying symptoms
  • disinfect surfaces and the belongings of the infected person
  • teach your children proper sanitary practices
  • avoid directly touching your face, nose, or mouth
  • don’t share utensils with the infected

Even with proper sanitary practices, one can easily catch a viral infection at times. However, they are generally of no concern and go away within a week.

Frequently asked questions

How many days does a viral fever last?

A viral fever typically lasts for 3 to 7 days, although it can last for up to 2 weeks in some cases. The overall duration of the fever depends upon your overall health, the causative virus, and if you have other health conditions.

If your fever persists for more than a week, it is recommended that you see a doctor.

How does viral fever spread?

Viral fever is caused by infection from a virus. While all viral diseases are not contagious, common infections like the flu and the common cold can spread from one person to another by:

  • breathing (respiratory droplets)
  • the patient’s utensils
  • shared food
  • bodily fluids
  • bites from carriers like insect

To prevent the spread of the infection, the patient should try to remain isolated.

Does viral fever cause loss of taste and smell?

The loss of smell can occur as a symptom of viral fever due to nasal congestion, although it returns as your congestion is relieved. However, the loss of taste and smell is typically an early symptom of COVID-19.

Does viral fever cause weight loss?

Short-term illnesses like viral fever can cause unintentional weight loss due to abdominal discomfort or diarrhea. If you experience rapid weight loss, you should seek medical attention to rule out any other health condition.

Should I take antibiotics for a viral fever?

Antibiotics are medicines that help fight bacterial infections by destroying or slowing down the growth of bacteria. As viral infections are caused by viruses, antibiotics are ineffective in treating them.

In a nutshell

A viral fever is an immune response generated by your body when it comes in contact with a viral infection, like the common cold or the flu.

Most viral fevers are of no concern and go away within a few days. However, some cases can result in severe symptoms and other complications. These may require medical attention, proper rest, and antiviral medications.

If an adult’s temperature reads higher than 103°F (39°C), a child younger than 3 months old has a rectal temperature of 100.4°F (38°C) or higher, or a child older than 3 months old has a temperature higher than 102.2°F (39°C), you should seek immediate medical assistance.