Influenza (Flu) in Children

By Wheeler, Brooke 
September 09, 2017

Influenza (Flu) in Children

What is the flu in children?

Influenza (flu) is a very contagious viral infection that affects the air passages of the lungs. It causes a high fever, body aches, a cough, and other symptoms. It is one of the most severe and common viral illnesses of the winter season. Most children are ill with the flu for less than a week. But some children have a more serious illness and may need to be treated in the hospital. The flu may also lead to lung infection (pneumonia) or death.

What causes the flu in a child?

The flu is caused by flu viruses. Flu viruses are divided into 3 types:

  • Influenza types A and B. These 2 types of viruses cause widespread illness (epidemics) almost every winter. They often lead to more people needing to go to the hospital, and more people dying from the flu. Public health officials focus on stopping the spread of types A and B. One of the reasons the flu remains a problem is because the viruses change (mutate) often. This means that people are exposed to new types of the viruses each year.
  • Influenza type C. This type of virus causes a very mild respiratory illness or no symptoms at all. It does not cause epidemics. It does not have the severe public health impact that influenza types A and B do.

A flu virus is often passed from child to child through sneezing or coughing. The virus can also live for a short time on surfaces. This includes doorknobs, toys, pens or pencils, keyboards, phones and tablets, and countertops. It can also be passed through shared eating utensils and drinking. Your child can get a flu virus by touching something that was touched by an infected with person, and then touching his or her mouth, nose, or eyes.

People are most contagious with the flu 24 hours before symptoms start, continuing while symptoms are most active. The risk of infecting others usually stops around day 7 of the illness. Because the flu can be spread before symptoms start, it’s easy to pick up a flu virus. This is true especially with children, who often touch many surfaces and then their mouth, nose, or eyes.

Which children are at risk for the flu?

A child is more at risk for the flu if he or she:

  • Is around people infected with the flu
  • Has not had the flu vaccine
  • Does not wash his or her hands after touching infected surfaces

Young children and children with certain underlying health conditions are at increased risk for a hospital stay or severe or complicated influenza infection. 

What are the symptoms of the flu in a child?

The flu is a respiratory disease, but it can affect the whole body. A child can become suddenly ill with any or all of these symptoms:

  • Fever, which may be as high as 103°F (39.4°C) to 105°F (40.5°C)
  • Body aches, which may be severe
  • Headache
  • Sore throat
  • Cough that gets worse
  • Tiredness
  • Runny or stuffy nose

In some cases, your child may also have symptoms such as:

  • Nausea
  • Vomiting
  • Diarrhea

Most children recover from the flu within a week. But they may still feel very tired for as long as 3 to 4 weeks.

It’s important to note that a cold and the flu have different symptoms:

Cold symptoms Flu symptoms
Low or no fever High fever
Sometimes a headache Headache in most cases
Stuffy, runny nose Clear nose, or stuffy nose in some cases
Sneezing Sneezing in some cases
Mild, hacking cough Cough, often turning severe
Mild body aches Severe body aches
Mild tiredness Extreme tiredness that can last weeks
Sore throat Sore throat in some cases

A cold is usually mild and often goes away after a few days. The flu can cause severe symptoms and lead to problems such as pneumonia and even death. The symptoms of the flu can be like other health conditions. Make sure your child sees his or her healthcare provider for a diagnosis.

How is the flu diagnosed in a child?

The healthcare provider will ask about your child’s symptoms and health history. He or she will give your child a physical exam. The symptoms are often enough to diagnose the flu. Your child’s provider may do other tests, depending on your child’s symptoms and overall health. 

How is the flu treated in a child?

Treatment will depend on your child’s symptoms, age, and general health. It will also depend on how severe the condition is. The goal of treatment is to help prevent or ease symptoms.

Treatment may include medicines such as:

  • Acetaminophen. This is to help lessen body aches and fever. Don't give aspirin to a child with a fever.
  • Cough medicine. This may be prescribed by your child’s healthcare provider.
  • Antiviral medicine. This may help to ease symptoms, and shorten the length of illness. This medicine does not cure the flu. The medicine must be started within 2 days after symptoms begin.

Antibiotics aren’t effective against viral infections, so they are not prescribed. Instead, treatment focuses on helping ease your child’s symptoms until the illness passes.

Talk with your healthcare providers about the risks, benefits, and possible side effects of all medicines.

Also make sure your child:

  • Gets lots of rest in bed
  • Drinks plenty of fluids

What are possible complications of the flu in a child?

The flu can cause severe breathing problems. A child with severe symptoms may need to stay in the hospital. The flu can lead to a lung infection called pneumonia. In some cases, the flu can lead to death.

How can I help prevent the flu in my child?

The best way to prevent flu is to have the yearly flu vaccine. The flu vaccine is given as a shot (injection). A nasal spray is not recommended for the 2017-2018 flu season. The CDC says this is because the nasal spray did not seem to protect against the flu over the last several flu seasons. 

Each year, a new flu vaccine is available before the start of the flu season. Talk with your healthcare provider if you have questions about how vaccines work and how well they prevent flu. The first time a child between the ages of 6 months and 8 years gets a flu vaccine, he or she will need a second flu vaccine one month later.

The vaccine is advised for all children 6 months and older. But for some children, it’s more critical for them to get a flu shot. The flu shot should be given to any child who has any of these:

  • A long-term heart or lung condition
  • An endocrine disorder such as diabetes
  • A kidney or liver disorder
  • Weak immune system from HIV/AIDS or long-term steroids
  • A blood disorder such as sickle cell disease

A flu shot should also be given to: 

  • A child who has a family member with a chronic health condition
  • A child or teen taking aspirin as long-term therapy
  • A child with parents or caregivers at high risk of complications from the flu

Some side effects of the vaccine can be like mild flu symptoms, but the vaccine does not cause the flu. Possible side effects of the flu vaccine include:            

  • Soreness in the arm where the shot was given
  • Short-term symptoms such as mild headache or a low-grade fever for about 1 day after the shot
  • In rare cases, an allergic reaction in a child who has a severe allergy to eggs. Vaccines are available for those with an egg allergy.

In addition to the flu vaccine, you can do other things to help reduce your child’s risk of getting the flu. You can also:

  • Limit your child’s contact with infected people, if possible.
  • Have your child wash his or her hands often

And you can help prevent your child spreading the flu to others if you:

  • Have your child cover his or her nose and mouth when coughing or sneezing. Use a tissue or cough or sneeze in the crook of the arm.
  • Wash your hands before and after caring for your child.
  • Clean surfaces in the home that others may touch.

When should I call my child's healthcare provider?

Call the healthcare provider if your child has:

  • Symptoms that don’t get better, or get worse
  • New symptoms

Key points about the flu in children

  • Influenza (flu) is a very contagious viral infection of the respiratory system.
  • It causes a high fever, body aches, a cough, and other symptoms.
  • Most children are ill with the flu for less than a week. But some children have a more serious illness and may need to be treated in the hospital. The flu may also lead to lung infection (pneumonia) or death.
  • The flu may be treated with acetaminophen, cough medicine, and antiviral medicine. Your child will also need lots of rest and drinking plenty of fluids.
  • The best way to prevent flu is to have the yearly flu vaccine. Because the viruses change, researchers create a new flu vaccine each year to help protect against strains of the virus that are currently active. The vaccine is advised for all children 6 months and older.

Next steps

Tips to help you get the most from a visit to your child’s healthcare provider:

  • Know the reason for the visit and what you want to happen.
  • Before your visit, write down questions you want answered.
  • At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you for your child.
  • Know why a new medicine or treatment is prescribed and how it will help your child. Also know what the side effects are.
  • Ask if your child’s condition can be treated in other ways.
  • Know why a test or procedure is recommended and what the results could mean.
  • Know what to expect if your child does not take the medicine or have the test or procedure.
  • If your child has a follow-up appointment, write down the date, time, and purpose for that visit.
  • Know how you can contact your child’s provider after office hours. This is important if your child becomes ill and you have questions or need advice.


September 09, 2017


Seasonal influenza in children: Clinical features and diagnosis, Up To Date, Seasonal influenza in children: Prevention and treatment with antiviral drugs, Up To Date

Reviewed By:  

Cunningham, Louise, RN,Freeborn, Donna, PhD, CNM, FNP,Lentnek, Arnold, MD