Overview: Influenza (Flu) in Children
Flu season is fast-approaching, and there is much to know about the flu! You may have some questions about how you can help keep your child healthy or what you should do if your child becomes ill. Staying up to date on the latest information is key to navigating the sick season ahead with little ones. Learn what the flu is and how it affects children—as well as how it may be treated and prevented.
What Is the Flu?
The flu, or influenza, is a viral illness that affects the respiratory system, specifically the nose, throat, and sometimes the lungs. It is a highly contagious infection that spreads easily from person to person, especially to children in group settings like school or daycare.
While the flu can share many of the same symptoms as the common cold, the flu can cause more serious illness and flu-related complications, like pneumonia or other secondary bacterial infections. Although most children have an uncomplicated illness that lasts less than a week, children younger than 5 years old—especially those under 2 years old or those of any age with certain chronic health conditions—are at an increased risk of severe illness and the development of potentially serious complications.
What Causes the Flu?
The flu is caused by an influenza virus that can be divided into 3 types—A, B, and C:
Influenza types A and B: These two types of viruses are typically responsible for yearly epidemics (outbreaks, or rapid spread of disease in communities) during the fall and winter months. They are the two more serious types of influenza, often leading to higher hospitalization rates and deaths. Public health efforts used to control or slow the spread and impact of influenza typically focus on types A and B, however, these viruses mutate (or change) regularly. This is why the flu remains a public health concern as new types of the virus emerge and can evade people’s immune systems each year. The goal of the yearly flu vaccine is to prevent illness from the more popular strand of mutated virus circulating that year.
Influenza type C: Unlike types A and B, this type of virus causes a very mild illness and may even cause no symptoms at all. It is not as common nor does it cause epidemics, and therefore it is not as much of a public health concern.
How Is the Flu Spread?
The flu is highly contagious, particularly 24 hours before the start of symptoms and for three days to a week after symptoms first appear. Some people, such as young children and those with weakened immune systems, could be contagious for even longer. Because people and children could be contagious with the flu before they even know they are sick, the flu is easily transmitted from person to person, making the spread difficult to control.
The flu is spread through contact with someone who is infected, either through the air or through touch:
Air—When an infected person coughs or sneezes, virus particles (droplets) can travel up to 12 feet in the air and can stay suspended in the air for varying amounts of time. If your child breathes in this air, the virus can stick to their nasal membrane, infecting them.
Touch—If your child directly touches an infected person or a contaminated object then touches their eyes, nose, or mouth, the virus can enter the body. Children often touch their face as well as other people and objects (like shared toys), making viruses easy to spread in young kids.
When Is “Flu Season?”
While it is possible to contract the flu at any time as influenza viruses spread year-round, flu activity typically peaks in the fall and winter months, known as flu season. Flu season usually spans from about October to May each year, with peak flu activity occurring between December and February. During flu season, the flu is particularly common in pre-school or school-aged children as well as teens and college students.
What Are the Signs and Symptoms of the Flu?
Children with the flu typically start to feel sick about two days after exposure to the flu virus, and symptoms appear suddenly. These may include any or all of the following:
Sudden fever—At or above 100.4°F (38°C) and may be as high as 103°F-105°F (39.4°C -40.5°C)—See How to Take Your Child’s Temperature for more information
Chills
Headache
Body/muscle aches
Fatigue/more tired than usual
Sore throat
Cough
Stuffy or runny nose
Vomiting
Diarrhea
A sore throat, stuffy nose, and continuing cough may become more apparent following the first few days of illness. While most people recover from the flu in about a week, many may feel exhausted for up to 3 to 4 weeks and/or may have a prolonged cough.
How Is the Flu Diagnosed?
The flu is usually diagnosed based on symptoms. Your child’s PCP may perform a physical exam where your child will be assessed. Since the signs and symptoms of the flu can present similarly to other conditions such as COVID-19, other tests may be ordered, like a nasal swab test or a throat culture. Determining the official diagnosis may be necessary for certain high-risk patients to help decide whether treatment with antivirals is needed.
Who Is Considered High-Risk for the Flu?
According to the American Academy of Pediatrics (AAP), while any child can develop severe, life-threatening influenza, there are some that are at an increased risk of developing complications:
Children younger than 5 years old (particularly those younger than 2 years old)
Those with underlying chronic medical conditions such as:
a. Lung, heart, or kidney disease
b. Weakened immune system
c. Cancer
d. Diabetes
e. Certain blood diseases
f. Conditions of the muscular or central nervous system
It is important for a child that is considered high-risk to be vaccinated and to avoid other people with the flu or flu-like symptoms when possible. Additional precautions may also be recommended by their primary care provider (PCP).
How Is the Flu Treated?
Your child’s primary care provider will determine how best to treat your child based on their age, severity of symptoms, and overall health. The goal of treatment is supportive to help relieve and prevent symptoms and discomfort. This may include over-the-counter pain relievers and fever reducers such as acetaminophen and ibuprofen. Do not give ibuprofen if your child is under 6 months old or if your child is dehydrated. Call your doctor if you do not know the recommended dose or if your child is younger than 2 years old. Do not give your child aspirin or other salicylates as it has been linked to a serious, potentially life-threatening disease called Reye syndrome that affects the liver and brain. Make sure to store all medications out of reach of children.
Other ways to help keep your child comfortable include:
Ensure they get proper rest
Encourage plenty of fluids such as breastmilk or formula for infants and water, electrolyte drinks (like Pedialyte, Enfalyte, or store brands), soup broth, popsicles, or flavored gelatin for older children
Children that are considered high-risk or those that are very ill may be prescribed antiviral medications. Antiviral medications may decrease the severity of symptoms, shorten the duration of illness, and may even prevent serious complications, like pneumonia. These drugs work best if they are started within the first one to two days of showing signs and symptoms of the flu. Treatment can be started later in some high-risk cases.
Your child should stay home from school or daycare until feeling better and fever-free for 24 hours without the aid of over-the-counter fever-reducing medications.
Antibiotics do not work against viral infections; they are used to fight against infections caused by bacteria. Since influenza is caused by a virus—not bacteria—your PCP will not prescribe an antibiotic for your child’s illness. However, sometimes children may develop complications or secondary infections during the flu from bacteria, like bacterial pneumonia. Your child’s PCP may order an antibiotic to treat one of these secondary infections if present.
When Should I Call My Child’s Primary Care Provider (PCP)?
The AAP recommends calling your child’s PCP to inquire about antiviral medications within the first 24 hours of your child’s first flu symptom if they have/are:
An underlying medical condition such as lung disease (like asthma), a heart condition, neuromuscular condition (like cerebral palsy), a weakened immune system, or other medical conditions
Younger than 5 years old (especially younger than 2 years old)
Symptoms that are not improving
In contact with others that are high-risk for complications of the flu (like those with weakened immune systems from chemotherapy)
Contact your child’s PCP or seek medical attention immediately if your child has any of the following:
Trouble or unusually rapid breathing
Blue lips or nails
Retractions—When the skin in the neck or between or below the ribs “sucks in” with each breath
Chest pain
Severe muscle pain that may cause your child to refuse to walk
Dehydration—No urine output for 8 hours, dry mouth, and no tears when crying
Not alert or interactive when awake
Seizures
Temperature over 104℉ (40℃) or a temperature at or above 100.4℉ (38℃) in infants less than 3 months old
Fever or cough that improve, then later return or worsen
Worsening chronic medical conditions, like asthma
How Can the Flu Be Prevented?
The yearly flu vaccine helps to boost your body’s protection and reduce the risk of serious complications from the flu. The Centers for Disease Control and Prevention (CDC) recommends that everyone 6 months of age and older receive yearly flu vaccines.
It is especially important for the following groups to receive their annual flu vaccine:
Children ages 6 months to 5 years old (including infants born pre-term)
Children any age over 6 months old with chronic medical conditions that increase their risk of complications
All contacts and caregivers of children under 5 years old and those with high-risk conditions
Those who are pregnant, considering pregnancy, have recently delivered, or are breastfeeding during the flu season—This is to protect both the parent and the baby since babies under 6 months old are unable to receive the flu vaccine
All healthcare workers
Other ways to prevent the flu include keeping your child away from a person who is sick with the flu. Encourage proper handwashing techniques both with soap and water and with hand sanitizer (containing at least 60% alcohol), and teach your child not to touch their nose, mouth, or eyes until their hands are properly washed. Additionally, children can be taught how to cough or sneeze into a tissue or their elbow (not their hands) and to not share towels, drinking glasses, or eating utensils. Toys and common play areas should be cleaned and sanitized regularly.
Cold vs. Flu: How Are they Different?
The signs and symptoms of the flu may seem similar to those of the common cold, however, it is important to remember that these are two very different illnesses. The flu is much more severe: Children (and adults!) tend to feel much sicker, achier, and more uncomfortable with higher fevers than those with just a cold. A common cold is usually mild and lasts a few days, whereas the flu can be serious, causing complications such as pneumonia or even death. It is important to keep these key differences in mind:
Cold vs. Flu
Use this chart to help identify the difference between the common cold and influenza signs and symptoms. Find more content like this here.
Flu vs. COVID-19: How Are they Different?
Both influenza and COVID-19 are respiratory illnesses caused by viruses. Signs and symptoms of influenza and COVID-19 are similar, such as fever, cough, difficulty breathing, shortness of breath, and body aches. Because it may be difficult to tell the difference between the flu and COVID-19 based on symptoms alone, testing is needed to confirm a diagnosis. Supportive care is important for both, but an official diagnosis may be needed for specific treatments such as antiviral therapy if your child has certain high-risk medical conditions.
Key Points to Remember
The flu is a highly contagious viral illness that affects the respiratory system. It can cause a sudden high fever, body aches, cough, and other symptoms that may appear similar to COVID-19. Testing should be considered for high-risk people so that appropriate antiviral medications may be initiated if indicated. Most children recover from the flu in about a week with supportive care, but some children may have more serious illness that may need to be treated in the hospital. The annual flu vaccine is recommended for all children 6 months old and older—it is important to get vaccinated to help protect both themselves and other high-risk people around them!
