Is it the flu, RSV, a cold, allergies or Covid?

It's like the least-fun guessing game ever.
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As winter sets in and the colder months take hold, we’re seeing a surge in flu cases across the country. With respiratory illnesses like the flu, COVID-19, and RSV making the rounds, it’s more important than ever to stay vigilant about your family’s health. Recent CDC data reveals that over 12 million flu illnesses and 160,000 hospitalizations have already been reported this season, highlighting the need for proactive measures.
As we move deeper into winter, flu and other viruses are expected to continue circulating, making it tricky to determine which illness your child might be battling when symptoms like coughs, sore throats, and congestion arise. While many illnesses have overlapping symptoms, here’s how you can better understand what might be affecting your child.
How symptoms differ between common winter illnesses
Many viruses and bacterial infections can have overlapping symptoms. But it’s helpful to know that there are some hallmark signs that can distinguish one from the other.
Here’s how symptoms of Covid can differ from the symptoms of flu, colds, RSV and seasonal allergies—but remember, you should always take a Covid test (we like the Lucira by Pfizer combined Covid & Flu test) or call your healthcare provider to confirm, because Covid symptoms can vary widely—and in some cases, may not be present at all. You should also pick up the phone or schedule a virtual visit with your pediatrician if you have concerns about the symptoms your child is showing.
Related: What if we didn’t have to worry about the ‘tripledemic’ this year?
COVID-19 symptoms in kids
Although COVID-19 cases have decreased in some areas, the virus is still circulating and can cause a wide range of symptoms in children. Symptoms of COVID-19 can overlap with those of other respiratory illnesses, including the flu and common cold, making it tricky to distinguish without testing.
Studies confirm that the latest monovalent COVID-19 vaccines provide strong protection against the newest strains, helping to minimize severe outcomes. Symptoms may include:
Symptoms may include:
- Congestion or runny nose
- Headache
- Sore throat
- Coughing
- Fever
- Nausea
- Diarrhea
- Shortness of breath
- Difficulty breathing
Headache, sore throat, runny nose and fever are the most common symptoms that present in kids with Covid. Shortness of breath tends to be more commonly seen in adults.
Unfortunately for parents everywhere, these are also highly common symptoms of colds and flu.
Related: How a pediatric ER doc stocks her medicine cabinet for cold + flu season 😷
Flu symptoms in kids
Flu cases are on the rise this winter, with seasonal flu activity continuing to be elevated across much of the country.
Flu symptoms can appear suddenly and are often more severe than those of a common cold. This season, influenza A viruses, particularly A(H1N1)pdm09 and A(H3N2), are most prevalent, and they’re contributing to widespread illness. In fact, the Centers for Disease Control and Prevention (CDC) has reported over 12 million flu-related illnesses, with 160,000 hospitalizations and 6,600 deaths so far.
Symptoms of influenza (flu) tend to come on suddenly rather than gradually, and usually include fever (100.4 degrees or higher). Flu symptoms may cause your child to feel worse than they might feel with a common cold. Body aches are common.
Symptoms may include:
- Sudden onset of fever (100.4°F or higher)
- Congestion
- Runny nose
- Cough
- Headache
- Muscle aches and pains
- General malaise
- Fever
- Sometimes nausea and vomiting
- Low appetite
The flu tends to hit quickly, often leading to more significant discomfort and fatigue than a cold. For young children, the flu can also be more serious, leading to complications like pneumonia or hospitalization.
Your child’s pediatrician or your local walk-in clinic can test your child for flu using a nasal swab. The primary treatment is rest and extra liquids, but some may need antiviral medications to relieve symptoms.
Common cold symptoms in kids
Common cold symptoms may be similar to those of the flu, but are generally milder.
Symptoms may include:
- Cough
- Congestion
- Runny nose
- Sore throat
- Possible low-grade fever
There’s no specific treatment for colds—they’re viruses that just need to run their course. Your child will likely still have good energy and a good appetite.
Related: I wasn’t prepared for my kids’ flu days this year
RSV symptoms in kids
RSV, or respiratory syncytial virus, is a separate condition that can cause cold-like symptoms in older children, but may cause a more severe lung disease in infants called bronchiolitis.
Symptoms may include:
- Clear, runny nose
- Decreased appetite
- Coughing
- Wheezing
- Sneezing
RSV tends to be most concerning for babies under 6 months of age, as their small airways are more susceptible to inflammation. Vaccines are available for some high-risk groups, including babies under 8 months old, and it’s highly recommended for pregnant women to get an RSV vaccine during their pregnancy to protect their newborns.
Shortness of breath, wheezing and fast heart rate are all symptoms of a more severe second stage of RSV. Contact your doctor or seek emergency medical treatment if your child has difficulty breathing.
Related: Health officials urge pregnant women to get vaccinated against flu, Covid and RSV
Seasonal allergy symptoms in kids
It’s not always easy to tell if your child has a cold or an allergy, but if there’s no fever and symptoms last one week or longer, it’s probably related to an allergy.
Symptoms may include:
- Sneezing
- Throat irritation or soreness
- Nasal congestion or runny nose
- Watery or red eyes
- Possible fluid buildup in the ears
If you’re worried about your child’s symptoms, remember, your safest move is to call your healthcare provider for a diagnosis or test.
Related: Which cold and flu medications can I take while breastfeeding?
Best bets for illness prevention
With so many viruses circulating this winter, including the flu, COVID-19, RSV, and the common cold, it’s crucial to take proactive steps to protect your family.
If there’s one small silver lining about this long list of ailments with overlapping symptoms, it’s that the preventative measures we can take to protect our families are straightforward, powerful multi-taskers:
Practice cold-and-flu-season hygiene
Habitual hand-washing, along with frequent cleaning and disinfection of high-touch areas, will go a long way toward protecting your family from infectious diseases including Covid, RSV, influenza and the common cold.
Stay home if you’re sick
Stopping the spread starts with reducing exposure to those around you and in your community. If you have any symptoms, stay home until you can take a Covid or flu test.
Make sure your family is vaccinated
Vaccinating all those who are eligible is the top recommendation from public health experts for preventing the spread of Covid, flu and RSV. Covid and flu vaccines are authorized for use in kids aged 6 months and up. The RSV shot may be given to babies aged 8 months or younger, or the maternal RSV vaccine may be offered to women during pregnancy.
Wear masks in crowded places
Wearing masks, especially N95 or medical-grade masks, can reduce the risk of catching or spreading respiratory viruses. This is particularly important in crowded or indoor settings where air circulation is limited.
Rest and hydrate
A well-rested and hydrated body is better equipped to fight off infections. Ensure that your family gets enough sleep and stays hydrated, as stress, sleep deprivation, and dehydration can weaken the immune system.
Related: American Academy of Pediatrics releases updated guidance ahead of flu season
When should you test, call the pediatrician, or seek urgent care?
With so many respiratory illnesses circulating and significant overlap in symptoms, it’s not always clear what the next step should be when your child starts feeling unwell. While mild symptoms can often be managed at home, there are times when testing or medical guidance is especially important.
Consider testing for Covid or flu if your child has:
- Fever along with cough, sore throat, or body aches
- Sudden onset of symptoms that worsen quickly
- Known exposure to someone who has tested positive for Covid or flu
- Symptoms that affect school attendance or childcare requirements
At-home combination tests can help reduce uncertainty around early symptoms and allow you to make faster decisions about treatment, isolation, and next steps, especially during nights, weekends, or peak illness seasons.
Call your pediatrician if symptoms:
- Last more than three to five days without improvement
- Include persistent fever, worsening cough, or ear pain
- Interfere with eating, drinking, sleep, or normal activity
- Raise concerns based on your child’s age or medical history
Seek urgent or emergency care right away if your child has:
- Trouble breathing, rapid breathing, or wheezing
- Blue or gray lips or fingernails
- Signs of dehydration such as very little urine, dry mouth, or no tears when crying
- High fever in infants, or fever that does not respond to medication
- Extreme fatigue, confusion, or difficulty waking
If something does not feel right, contacting a healthcare provider can help ensure your child receives timely care and appropriate guidance.
Related: Flu season, meet pandemic—here’s how parents can prepare
A version of this article was originally published on September 18, 2020. It has been updated on December 16, 2025.

















































































