Flu-like symptoms include fever, cough, congestion, body aches, headache, fatigue, and sore throat.

This article discusses flu-like symptoms and some of their possible causes.

It also explores treatment and prevention of various flu-like illnesses.

Boy with fever

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What Are Flu-Like Symptoms?

The World Health Organization’s clinical definition of flu-like illness no longer includes sore throat.

In other words, you may have a flu-like illness whether you have a sore throat or not.

What Conditions Can Cause Flu-Like Symptoms?

Aside from the flu itself, there are many possible causes of flu-like symptoms.

These may produce flu-like symptoms.

Another difference between the two is how quickly the symptoms come on.

While a cold gradually progresses symptom by symptom, flu symptoms come on all at once.

Strep Throat

Strep throat is a bacterial streptococcal infection that causes inflammation and intense throat pain.

It shares many symptoms with the flu beyond sore throat, including fever, chills, and muscle aches.

However, strep throat doesn’t usually include cough and nasal congestion.

Bronchitis

Bronchitis is the inflammation of the airways leading to the lungs.

Viral infections, such as the cold or flu, are the usual causes of acute bronchitis.

Viral Pneumonia

Viralpneumoniais an infection that causes inflammation in the lungs.

Mono symptoms tend to last longer than the flu and be more severe.

Respiratory Syncytial Virus (RSV)

This common virus can cause flu-like symptoms in adults and children.

Some children at high risk of developing severe bronchiolitis may benefit frommonoclonal antibodies.

Synagis and Beyfortus are not vaccines and cannot cure ortreat a child diagnosed with RSV.

If your child is at high risk for RSV infection, your pediatrician may discuss these options with you.

A baby with RSV may have trouble breathing and can become easily fatigued.

They may have difficulty feeding.

Importantly, meningitis causes inflammation around the brain and spinal cord, which can cause a stiff neck.

This symptom is not common with influenza and other flu-like illnesses.

Meningitis typically requires hospitalization.

Other Coronaviruses

Besides COVID-19, a number of coronaviruses can cause flu-like symptoms.

More dangerous types can lead to pneumonia and death.

In addition, there may be a rash, swollen lymph nodes, andmouth ulcers.

Although these symptoms usually resolve within a few weeks, HIV is a chronic illness.

Unfortunately, these antiviral medications are ineffective against flu-like illnesses that are not triggered by the influenza virus.

For most flu-like viral infections, treatment starts with self-care.

Antibiotics are only needed if a bacterial cause is diagnosed, as with strep throat or bacterial pneumonia.

You should also check that you have received a COVID-19 vaccine and the boosters recommended by your healthcare provider.

Most other flu-like illnesses can’t be prevented with vaccines, medications, or supplements.

Other conditions such as the common cold and COVID-19 can also cause these symptoms.

These are referred to as “flu-like illnesses.”

Most flu-like illnesses can be successfully managed at home.

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