Flu in Children: Symptoms, Treatment & When to Seek Care

What Is Influenza (Flu)?

Influenza, commonly called the flu, is a contagious respiratory infection caused by influenza viruses. It affects the nose, throat, and lungs. In children, flu typically causes sudden high fever (39-40°C/102-104°F), severe body aches, dry cough, and extreme fatigue. The flu is most common during winter months and is often called "seasonal flu."

Influenza is a significant respiratory illness that affects millions of children worldwide each year. Unlike the common cold, which develops gradually with milder symptoms, the flu strikes suddenly and with much greater intensity. A child who seemed perfectly healthy in the morning can be extremely ill by afternoon, running a high fever and feeling completely exhausted.

The influenza virus is highly contagious and spreads primarily through respiratory droplets when an infected person coughs, sneezes, talks, or even breathes. Children are particularly efficient at spreading the flu because they are less likely to cover their coughs and sneezes effectively, and they frequently touch their faces and shared surfaces. In school and daycare settings, the virus can spread rapidly through a group of children within days.

There are different types of influenza viruses, with types A and B being the most common causes of seasonal flu in humans. These viruses constantly mutate, which is why new flu vaccines are developed each year to match the circulating strains. Type A flu tends to cause more severe illness and is responsible for flu pandemics, while type B flu generally causes milder disease but can still lead to serious complications in vulnerable individuals.

Children have the highest rates of influenza infection of any age group, with 20-30% of children becoming infected during a typical flu season. This is partly because their immune systems are still developing and haven't been exposed to as many flu strains as adults. Young children in daycare or school are especially likely to catch and spread the flu due to close contact with other children.

Why Children Are More Vulnerable

Children face unique challenges when dealing with influenza. Their immune systems are still maturing, which means they may take longer to fight off the infection and are more susceptible to secondary complications. Additionally, young children have smaller airways that can become more easily obstructed by swelling and mucus, potentially leading to breathing difficulties.

Children under 5 years old, and especially those under 2 years, are at highest risk for serious flu-related complications. This increased vulnerability stems from their developing immune systems, smaller respiratory passages, and limited ability to clear secretions effectively. These young children are more likely to require hospitalization and intensive medical care when they develop influenza.

What Are the Symptoms of Flu in Children?

Flu symptoms in children appear suddenly and include high fever (39-40°C/102-104°F), dry cough, severe body aches, headache, extreme fatigue, sore throat, and runny nose. Unlike adults, children often also experience nausea, vomiting, diarrhea, and stomach pain. Symptoms are typically most severe during the first 3-4 days.

Recognizing flu symptoms in children is crucial for providing appropriate care and knowing when to seek medical attention. The hallmark of influenza is the sudden onset of symptoms - children typically go from feeling well to feeling very sick within just a few hours. This rapid progression helps distinguish flu from the common cold, which develops more gradually over several days.

The most common symptoms of flu in children include a combination of respiratory and systemic complaints. High fever is almost universal, typically ranging from 39-40°C (102-104°F), though some children may develop even higher temperatures. This fever often lasts 3-5 days, though it can persist for up to a week in some cases. The fever is usually accompanied by chills and may cause significant discomfort.

A dry, hacking cough is another characteristic symptom that often develops early in the illness and may persist for 1-2 weeks after other symptoms have resolved. This cough is typically non-productive at first but may become more productive as the illness progresses. The cough can be severe enough to cause chest discomfort and may worsen at night, disrupting sleep.

Body aches and muscle pain are particularly prominent in flu compared to other respiratory infections. Children may complain of aching legs, back pain, or general soreness throughout their bodies. These aches are caused by the body's inflammatory response to the viral infection and can make children reluctant to move or participate in normal activities.

Symptoms Unique to Children

Children under 2 years often exhibit symptoms that are less common in older children and adults. Gastrointestinal symptoms such as nausea, vomiting, diarrhea, and abdominal pain frequently accompany the respiratory symptoms in young children. These symptoms can be mistaken for a stomach bug, but when they occur alongside high fever and respiratory symptoms, flu should be suspected.

Young children and infants may also display non-specific symptoms that require careful attention from caregivers. These can include unusual fussiness or irritability, decreased appetite or refusal to eat, decreased activity level or unusual sleepiness, and dehydration signs such as fewer wet diapers. Infants may be more difficult to console than usual and may have trouble sleeping despite appearing exhausted.

How Does Flu Spread?

Flu spreads mainly through respiratory droplets when infected people cough, sneeze, talk, or breathe. Children can also catch flu by touching contaminated surfaces and then touching their eyes, nose, or mouth. The virus can survive on surfaces for hours. People are most contagious in the first 3-4 days of illness but can spread flu 1 day before symptoms start.

Understanding how influenza spreads is essential for protecting children and preventing outbreaks in schools, daycare centers, and homes. The primary mode of transmission is through respiratory droplets that are expelled when an infected person coughs, sneezes, talks, or even breathes. These droplets can travel up to 2 meters (6 feet) and land in the mouths or noses of nearby people, or be inhaled into the lungs.

Contact transmission also plays a significant role in flu spread, particularly among children. When an infected child touches their nose or mouth and then touches a toy, doorknob, or other surface, they deposit virus particles that can survive for several hours. Other children who touch these contaminated surfaces and then touch their own faces can become infected. This is one reason why frequent handwashing is so important for flu prevention.

The incubation period for influenza - the time between exposure and the appearance of symptoms - is typically 1-3 days. This relatively short incubation period contributes to the rapid spread of flu through communities. People can begin spreading the virus before they even know they are sick, making it challenging to prevent transmission through isolation alone.

When Are Children Most Contagious?

Children can begin spreading the flu virus approximately 1 day before symptoms appear, which is why flu can spread so rapidly through schools and families. The period of highest contagiousness coincides with when symptoms are most severe, typically during the first 3-4 days of illness. However, children may continue to be infectious for up to 7 days after becoming sick, and some young children and those with weakened immune systems may shed the virus for even longer periods.

Most children stop being contagious once their fever has been gone for at least 24 hours without the use of fever-reducing medications. This is why many schools and daycare centers require children to be fever-free for a full day before returning. However, children with significantly weakened immune systems may remain contagious for longer periods, and their healthcare providers can advise on appropriate precautions.

How Can I Care for My Child with Flu at Home?

Home care for children with flu focuses on rest, hydration, and fever management. Ensure your child drinks plenty of fluids, gets adequate rest, and takes fever-reducing medication if uncomfortable. Keep the room comfortable and allow your child to eat when hungry. Most children recover within 1-2 weeks with supportive care at home.

Caring for a child with the flu can be challenging, but most children recover well with proper home care and do not require hospitalization or prescription medications. The foundation of flu treatment in children is supportive care, which means treating symptoms and ensuring the child's body has what it needs to fight off the infection naturally.

Rest is fundamental to recovery from influenza. Children's bodies are working hard to fight the viral infection, and rest allows their immune systems to function optimally. Encourage your child to stay in bed or on the couch, but don't force them to lie still if they want to get up occasionally. Allow them to engage in quiet activities like reading, watching shows, or coloring when they feel up to it, but discourage active play until they are significantly better.

Hydration is critically important, especially when children have fever. Fever increases fluid loss through sweating and increased breathing rate, and children can become dehydrated quickly if they don't drink enough. Offer small, frequent sips of water, clear broths, diluted fruit juice, or oral rehydration solutions. Don't worry if your child doesn't eat much - appetite typically returns as they recover - but drinking is essential.

Rest and Comfort

Creating a comfortable environment can help your child rest more easily. Keep the room at a comfortable temperature - slightly cool is often better than warm when a child has fever. Use light clothing and bedding rather than bundling them up, as this can actually make fever worse. Opening a window briefly to let in fresh air can also help your child feel more comfortable.

Alternate between rest and gentle movement as your child tolerates. When they are lying down, encourage them to change positions occasionally and sit up from time to time. Once they start feeling better, gentle movement around the house can actually help prevent complications like pneumonia by keeping the lungs clear.

Nutrition and Hydration

While appetite is often reduced during flu, hydration remains essential. Signs of dehydration to watch for include decreased urination (fewer wet diapers in infants), dark urine, dry mouth and lips, crying without tears, and unusual drowsiness or irritability. If you notice these signs, increase fluid intake and contact your healthcare provider if they don't improve.

When your child does feel like eating, offer light, easily digestible foods. Good options include clear soups and broths, crackers or toast, bananas, applesauce, rice, and plain pasta. Avoid heavy, greasy, or spicy foods that may upset the stomach, especially if your child has been experiencing nausea or vomiting.

Sore Throat and Cough Relief

A sore throat can be soothed with warm or cool drinks, depending on what your child prefers. Honey can help soothe sore throats and reduce coughing in children over 1 year of age - never give honey to infants under 1 year due to the risk of infant botulism. Ice pops, smoothies, and cold yogurt may also feel soothing on an inflamed throat.

For cough, keeping the air moist can help. A cool-mist humidifier in your child's room can ease coughing, especially at night. Over-the-counter cough medicines are generally not recommended for young children under 6 years as they have limited effectiveness and potential side effects. For older children, consult with a pharmacist about appropriate options.

What Medication Can I Give My Child for Flu?

Fever-reducing medications like paracetamol (acetaminophen) can be given from 3 months of age, and ibuprofen from 6 months. Always dose based on weight, not age, and follow package instructions carefully. Never give aspirin to children under 18 due to the risk of Reye's syndrome. Consult a doctor before giving any medication to infants under 6 months.

Fever is one of the body's natural defenses against infection - it helps the immune system fight off viruses. For this reason, fever itself doesn't always need to be treated. However, if your child is uncomfortable, having trouble sleeping, or the fever is very high, fever-reducing medication can provide relief and help them rest more comfortably.

Paracetamol (also known as acetaminophen) is the most commonly used fever reducer for children and can be given from 3 months of age. It comes in various forms suitable for children, including liquid suspensions, dissolving tablets, and suppositories. Always use the dosing device that comes with the medication and dose according to your child's weight rather than age for the most accurate dosing.

Ibuprofen is another effective fever reducer and pain reliever that can be used in children from 6 months of age. Like paracetamol, it comes in child-friendly formulations. Some parents find that alternating between paracetamol and ibuprofen helps maintain more consistent fever control, but this should only be done under the guidance of a healthcare provider to avoid confusion about dosing times.

Important Medication Warnings

Aspirin (acetylsalicylic acid) should never be given to children or teenagers under 18 years of age for fever or pain relief. In children with viral infections like flu, aspirin use has been linked to Reye's syndrome, a rare but serious condition that causes swelling in the liver and brain. Always check medication labels carefully, as aspirin may be present in some combination products.

For infants under 6 months old, always consult with a healthcare provider before giving any medication. Their bodies process drugs differently than older children, and proper dosing is essential for safety. If your infant under 3 months has any fever, contact your healthcare provider promptly, as fever in very young infants requires medical evaluation.

Antiviral Medications

In some cases, doctors may prescribe antiviral medications such as oseltamivir (Tamiflu) or zanamivir (Relenza) for children with flu. These medications work best when started within the first 48 hours of symptoms and can shorten the duration of illness by 1-2 days. They are most commonly prescribed for children at high risk of complications, including those under 2 years, children with chronic medical conditions, or those with severe illness.

Antiviral medications are not the same as antibiotics. Antibiotics do not work against flu because flu is caused by a virus, not bacteria. Antibiotics are only helpful if your child develops a secondary bacterial infection as a complication of the flu, such as bacterial pneumonia or an ear infection.

When Should I Take My Child to the Doctor?

Seek medical care if your child has: fever lasting more than 4 days, fever that returns after improving, difficulty breathing or rapid breathing, refusal to drink fluids, severe ear pain, unusual drowsiness, or sudden worsening of symptoms. Call emergency services immediately for bluish lips/face, difficulty breathing at rest, or unresponsiveness.

Most children with flu recover fully with home care and don't need to see a doctor. However, there are certain warning signs that indicate your child needs medical attention. Knowing these signs can help you make the right decision about when to seek care and when to continue managing symptoms at home.

Fever patterns can provide important information about how your child's illness is progressing. While high fever is expected with flu, fever that persists beyond 4-5 days may suggest a complication or secondary infection that needs evaluation. Similarly, if fever goes down and then returns, this could indicate a new problem developing and warrants medical attention.

Any breathing difficulties should be taken seriously. Signs of respiratory distress in children include rapid breathing (more than 40-50 breaths per minute depending on age), visible chest retractions (skin pulling in between ribs or at the base of the throat with each breath), flaring nostrils, grunting sounds with breathing, or turning blue around the lips or fingertips. These symptoms require urgent medical evaluation.

Contact a Healthcare Provider If

• Fever lasts more than 4 days or is very high (above 40°C/104°F)
• Fever improves but then returns, suggesting possible secondary infection
• Your child refuses to drink fluids or shows signs of dehydration
• Symptoms suddenly worsen after seeming to improve
• Your child develops ear pain (possible ear infection)
• Your child has a chronic medical condition (asthma, diabetes, heart disease, weakened immune system)
• Your child is under 2 years old with flu symptoms
• Your child is unusually drowsy, difficult to wake, or very irritable

How Long Should My Child Stay Home from School?

Children should stay home until they have been fever-free for at least 24 hours without using fever-reducing medication AND feel well enough to participate in normal activities. This is typically 5-7 days from when symptoms started, but may be longer for some children. Cough and tiredness may persist after other symptoms resolve.

Deciding when your child can return to school or daycare involves balancing their recovery needs with reducing the spread of infection to others. The general guideline is that children should remain at home until they have been fever-free for at least 24 hours without the use of fever-reducing medications. This helps ensure they are no longer at peak contagiousness and are well enough to manage a full day of activities.

Beyond fever, your child should feel well enough to participate in normal daily activities. A child who is still very fatigued, struggling to stay awake, or not eating and drinking normally may not be ready to return, even if their fever has resolved. The demands of a school or daycare day can be exhausting for a child who is still recovering, and returning too early can prolong the illness.

It's important to understand that some symptoms may persist after your child is well enough to return to activities. A lingering cough that is improving but not completely gone is common and doesn't necessarily mean your child needs to stay home if they are otherwise feeling better. Similarly, mild fatigue may persist for a week or two after the acute illness resolves.

Returning to Daycare or School

Before sending your child back, consider whether they can comfortably participate in all regular activities including outdoor play and physical education. If your child needs to rest frequently or can't keep up with the group, they may not be ready. Young children in daycare are particularly vulnerable to becoming overtired and having a setback if they return before fully recovered.

When in doubt, err on the side of keeping your child home for an extra day. This benefits both your child's recovery and helps protect their classmates from infection. Communicate with your child's school or daycare about their policies for returning after illness, as some facilities may have specific requirements.

Which Children Are at Higher Risk for Complications?

Children at higher risk for flu complications include: those under 5 years (especially under 2), children with asthma, diabetes, heart disease, weakened immune systems, neurological conditions, or obesity. These children should receive the annual flu vaccine and may need antiviral treatment if they get flu.

While most healthy children recover from flu without problems, some children are at higher risk for developing serious complications. Identifying high-risk children is important because they may benefit from preventive measures like vaccination and may need closer monitoring or earlier medical intervention if they do get the flu.

Age is an important risk factor for flu complications. Children under 5 years old are at increased risk, with those under 2 years being at highest risk for serious flu-related complications. Very young children's immune systems are still developing, and their small airways can become more easily obstructed. Infants under 6 months cannot receive the flu vaccine, so protecting them depends on vaccinating those around them (known as "cocooning").

Children with certain chronic medical conditions face increased risks when they develop influenza. These conditions include asthma and other chronic lung diseases, heart conditions, diabetes, kidney or liver disease, neurological and neurodevelopmental conditions (such as cerebral palsy, epilepsy, or developmental delays), weakened immune systems (due to disease or medications), and severe obesity. Children with these conditions should receive their annual flu vaccine and contact their healthcare provider promptly if they develop flu symptoms.

Why Higher-Risk Children Need Extra Care

For high-risk children, the flu is more likely to lead to complications such as pneumonia, worsening of underlying conditions, and hospitalization. Their healthcare providers may recommend antiviral treatment even before test results confirm influenza, as early treatment is most effective. These children and their families should have a plan in place for what to do if flu symptoms develop.

Vaccination is especially important for high-risk children. While the flu vaccine doesn't guarantee prevention, it significantly reduces the risk of infection and, importantly, reduces the severity of illness if infection does occur. Vaccinated children who get the flu tend to have milder illness, shorter duration, and fewer complications compared to unvaccinated children.

What Are the Possible Complications of Flu?

Flu complications in children include ear infections (most common), sinus infections, pneumonia (viral or bacterial), worsening of asthma, and rarely, inflammation of the heart or brain. Most complications are treatable, but some require hospitalization. Seek care if symptoms worsen after initial improvement or if your child has difficulty breathing.

Most children recover from flu without developing any complications. However, in some cases, the flu can lead to secondary problems that require additional medical treatment. Understanding these potential complications helps parents know what to watch for and when to seek care.

Ear infections (otitis media) are the most common complication of flu in children, particularly in those under 5 years. The inflammation and congestion caused by the flu can block the drainage of the middle ear, allowing bacteria to multiply and cause infection. Signs of an ear infection include ear pain, pulling or rubbing at the ear (in infants), fever that returns after improvement, and fussiness or crying when lying down.

Sinus infections can also develop as a secondary complication, particularly in older children. When cold and flu cause swelling in the nasal passages, the sinuses may not drain properly, leading to bacterial overgrowth. Signs that a sinus infection may have developed include nasal congestion and discharge that worsens after initial improvement, facial pain or pressure, and fever returning after it had gone.

Pneumonia

Pneumonia is a more serious complication that can occur when the flu infection spreads to the lungs or when bacteria take advantage of the flu-weakened respiratory system to cause a secondary infection. Signs of pneumonia include fever that persists or returns, rapid or labored breathing, chest pain when coughing or breathing deeply, and a productive cough with colored mucus. Pneumonia usually requires medical treatment and sometimes hospitalization, especially in young children.

Other Complications

Other less common but possible complications include croup (inflammation of the upper airway causing a barking cough), bronchitis, worsening of asthma, and rarely, myocarditis (inflammation of the heart) or encephalitis (inflammation of the brain). Some children experience temporary muscle pain in their calves after flu - this condition, called benign acute childhood myositis, is harmless and resolves within a few days.

How Can I Protect My Child from Getting the Flu?

The best protection is annual flu vaccination, recommended for all children 6 months and older. Additional prevention includes frequent handwashing, avoiding touching the face, staying away from sick people, and teaching proper cough/sneeze etiquette. Keeping children home when sick prevents spreading flu to others.

Preventing influenza is much better than treating it, and there are several effective strategies parents can use to reduce their children's risk of catching and spreading the flu. The most effective preventive measure is annual flu vaccination, which is recommended for all children 6 months of age and older by major health organizations worldwide including the World Health Organization (WHO), the Centers for Disease Control and Prevention (CDC), and the American Academy of Pediatrics (AAP).

The flu vaccine is reformulated each year to match the influenza strains expected to circulate during the upcoming flu season. Vaccination typically begins in early fall and continues throughout the flu season. It takes about two weeks after vaccination for the body to develop protective immunity, so getting vaccinated before flu begins circulating in your community is ideal.

Good hand hygiene is another cornerstone of flu prevention. Teach children to wash their hands frequently with soap and water for at least 20 seconds, especially before eating, after using the bathroom, and after coming in from outside. When soap and water aren't available, alcohol-based hand sanitizers with at least 60% alcohol can be used as an alternative.

Practical Prevention Tips

• Get the flu vaccine annually: Recommended for all children 6 months and older
• Wash hands frequently: With soap and water for at least 20 seconds
• Avoid touching the face: Viruses enter through eyes, nose, and mouth
• Stay away from sick people: Avoid close contact when possible
• Cover coughs and sneezes: Use the elbow, not hands
• Clean frequently touched surfaces: Doorknobs, light switches, toys
• Don't share cups and utensils: Especially during flu season
• Keep sick children home: To prevent spreading illness to others
• Spend time outdoors: Virus spreads less easily in open air

Flu During Pregnancy and Breastfeeding

Pregnant women with flu do not transmit the virus to their unborn baby. Women who are breastfeeding can and should continue breastfeeding when they have flu - breast milk provides protective antibodies to the baby. Flu vaccination is recommended and safe during pregnancy and breastfeeding.

If you are pregnant and caring for a child with flu, or if you develop flu yourself, you may have concerns about the impact on your unborn baby. Reassuringly, the influenza virus does not pass through the placenta to infect the developing baby. However, pregnant women are at higher risk for flu complications due to changes in their immune system, heart, and lungs during pregnancy, so prevention and prompt treatment are important.

Women who are breastfeeding can and should continue to breastfeed their babies when they have the flu. Breast milk contains antibodies that help protect the baby from infection, and continuing to breastfeed during illness passes these protective antibodies to your baby. If you are too ill to breastfeed directly, you can express milk for someone else to feed to your baby.

Flu vaccination is strongly recommended for pregnant women and is safe during any trimester of pregnancy. Vaccination during pregnancy protects both the mother and provides some protection to the newborn during the first few months of life, before the baby can receive their own vaccine. Women who are breastfeeding can also safely receive the flu vaccine.