Early flu symptoms include a sore throat, body aches, and chills. Symptoms in children may present differently to adults.

Those who get the flu are most contagious within the first 3-4 days after developing the illness. As such, recognizing early flu symptoms could help stop the transmission of the virus to others. Early treatment may also provide greater symptom relief.

COVID-19, the infection caused by SARS-CoV-2, can produce similar symptoms to those of the flu, but it is not the same. A persistent dry cough, a fever, and fatigue are some common symptoms of this infection.

Learn how to tell if someone has COVID-19 or the flu here.

In this article, we list some common early flu symptoms in both children and adults. We also discuss treatment options and methods of prevention.

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Early flu symptoms typically appear between 1 and 4 days after exposure to the virus. At first, the symptoms can resemble those of the common cold, and include:

  • unusual tiredness
  • a runny nose
  • sneezing
  • a sore throat

These may quickly become worse, and additional symptoms may develop, such as:

  • chills
  • excessive fatigue
  • a fever over 100.4oF
  • a headache
  • muscle aches and pains
  • nasal congestion
  • a persistent cough
  • sweats
  • weakness

Some strains of the flu can also cause gastrointestinal issues, such as nausea, diarrhea, or vomiting.

Not everyone who has the flu will experience all of these symptoms. Some people develop relatively mild symptoms, while others have more severe ones.

Flu resources

For more information and resources to help keep you and your loved ones healthy this flu season, visit our dedicated hub.

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The symptoms of COVID-19 may appear 2–14 days after exposure to the virus, according to the Centers for Disease Control and Prevention (CDC).

They include:

  • a fever
  • a cough
  • shortness of breath

The World Health Organization (WHO) add that there may also be:

  • aches and pains
  • nasal congestion
  • a runny nose
  • a sore throat
  • diarrhea

These are often mild, but some people develop severe symptoms. These include:

  • difficulty breathing
  • persistent pain or pressure in the chest
  • a bluish tint to the lips or face
  • confusion and changes in consciousness

If anyone experiences these symptoms, someone should call 911 and ask for emergency assistance.

Learn more about COVID-19 symptoms here.

Different age groups may experience specific symptoms. Warning signs, which indicate that urgent treatment is necessary, also differ between adults and children.

Additional signs in children

In addition to the symptoms listed above, other signs of the flu virus in toddlers and children include:

  • being less active
  • crying without tears
  • difficulty urinating or infrequent urination
  • drinking fewer fluids
  • having a rash along with a fever
  • interacting with caregivers less
  • eating less
  • sleeping more

Some of these symptoms — such as crying without tears or infrequent urination — indicate dehydration. Dehydration in children can become dangerous if not dealt with quickly.

Learn more about flu symptoms in toddlers here.

Individuals who have concerns about flu signs and symptoms in children should call their pediatrician.


Children with COVID-19 will have similar symptoms to adults, but symptoms in children are often mild. However, children with underlying health conditions may have a higher risk of experiencing severe symptoms.

According to the CDC, children have experienced cold-like symptoms such as:

  • a fever
  • a runny nose
  • a cough

However, experts do not yet know exactly how COVID-19 affects children. Anyone of any age who has symptoms will need careful monitoring. If a child has worsening symptoms, such as breathing difficulties, they will need emergency attention. This also goes for adults.

Warning signs in children

Warning signs requiring urgent treatment include:

  • bluish face or lips
  • chest pain
  • difficulty breathing or rapid breathing
  • fever above 104oF (or any fever in babies under 12 weeks of age)
  • a fever or cough that improves but then worsens
  • lack of alertness or inability to interact with others when awake
  • pulling in of the ribs during inhalations
  • refusing to walk (due to severe muscle pain)
  • seizures
  • signs of dehydration that do not resolve quickly
  • worsening of chronic medical problems

Children who develop severe symptoms of flu will require medical attention.

Warning signs in adults

Adults should seek urgent medical care if they experience:

  • difficulty breathing
  • a fever or cough that improves but then worsens
  • an inability to urinate
  • persistent chest or stomach pain
  • persistent dizziness or confusion
  • seizures
  • severe muscle pain
  • shortness of breath
  • weakness and loss of balance
  • worsening of other medical conditions

Additional signs and symptoms in older adults

Older adults, especially those aged 65 or older, are at high risk of developing serious flu complications. The CDC recommend prompt treatment for over those over 65 with flu symptoms.

Older adults are also more susceptible to dehydration, possibly because as some people age, they are less aware of being thirsty and may have a reduced sense of the need to urinate.

Therefore, people in this age group and their caregivers should be aware of the symptoms of dehydration and seek treatment if they occur. Symptoms include:

  • confusion
  • dark-colored urine
  • dizziness
  • fatigue
  • less frequent urination

Extreme thirst is also an indicator of dehydration. However, according to one study, it is not always a reliable one in older adults. Do not wait until thirst becomes severe to seek treatment.

Older people with COVID-19 are more likely to develop severe symptoms, such as breathing difficulties. Other groups at higher risk include people with underlying health conditions, such as diabetes, heart disease, lung disease, cancer, and high blood pressure.

There are ways to reduce the risk of getting the flu. One of the most effective ways is to get the flu vaccine every year. The CDC recommend that everyone 6 months and older get the flu vaccine, including pregnant women.

There are some rare exceptions to this recommendation — concerned individuals should speak to their doctor about their suitability for the vaccine.

Other methods of flu prevention include:

  • avoiding contact with those who have the flu
  • staying home when sick, to prevent transmission of the flu to others
  • washing hands thoroughly and frequently with soap, and for at least 20 seconds
  • avoiding touching the face as much as possible
  • using an alcohol-based hand sanitizer of at least 60% alcohol content, when it is not possible to wash the hands

In some cases, such as the COVID-19 pandemic, experts may ask people to practice physical distancing. This means staying at least 6 feet (2 meters) from other people in public places. Wearing a face covering can also help reduce the risk of spreading a virus that transmits through droplets.

Typically, treatment for the flu involves staying hydrated and resting. However, those who are at higher risk of complications, or those who have severe symptoms may need additional treatments.

Treatment varies from person to person. It depends on the person’s age and health, the type of flu they have, and how long they have had symptoms. Options include medications and home remedies.

Home remedies

Home remedies for the flu include:

  • drinking plenty of fluids, such as water, juice, soup, and broth
  • resting as much as possible to help the body fight infection
  • taking oral rehydration solutions for dehydration
  • using over-the-counter pain relievers for muscle aches and headache

Children and teenagers can take an age-appropriate pain reliever. Aspirin is not suitable for children due to the risk of Reye’s syndrome, a rare illness that can be fatal.

Prescription medications

A doctor may prescribe an oral or inhaled antiviral medication. These reduce the length of time a person has the flu. Treatment with antiviral drugs must begin within the first 2 days of getting sick.

Examples include:

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

Many people who get the flu can successfully treat the illness at home.

However, children and older adults are more at risk of complications and should see a doctor. Adults who have severe flu symptoms, a suppressed immune system, or chronic medical conditions should also see a doctor.

Those who wish to get the flu vaccine, or find out more about it should speak to their doctor. While the CDC recommend getting the vaccine by the end of October each year, it is possible to get it throughout the flu season.

Anyone who develops breathing difficulties should seek immediate medical help.

Most people who get the flu will recover within a few days to 2 weeks without complications.

One of the most common complications is pneumonia, especially among younger children, pregnant women, those with underlying conditions, and older adults. If warning signs of worsening flu show, prompt treatment is necessary.

Getting the flu shot and taking preventive measures can reduce the risk of getting the flu. If flu symptoms develop, seeking prompt treatment, and practicing home care can reduce the likelihood of complications.