It usually starts with that annoying little tickle in the back of your throat. Maybe it shows up after a chilly Saturday morning at the hockey rink, or a few days after the furnace kicks on for the first time. By dinnertime, you’re reaching for the tissue box and wondering, “Is this a cold, is it the flu, is it the dry air, or are my allergies just acting up again?”
Here in Minnesota, late October and early November is when the sniffles really start making their rounds. The kids have all settled back into their classrooms, we’re spending a lot more time indoors, and Minnesota flu season is officially underway. The Minnesota Department of Health starts tracking the new respiratory season every October and keeps a close eye on it all the way through until spring. It’s also important to remember that the flu isn’t something that you should ignore. According to the CDC, the flu has sent anywhere from 120,000 to 710,000 Americans to the hospital each season over the past 15 years.
The tricky thing is that a cold, the flu, and allergies can all look very similar at first. At Entira, we care about helping you and your family feel your best all year long, so we put together this guide to help you understand the cold vs flu differences, where allergies fit into the picture, and when it’s time for you to give us a call.
Why Cold, Flu, and Allergy Symptoms Are So Easy to Mix Up
All three of these illnesses can leave you feeling stuffy, sneezy, and tired, so it’s no wonder that they often get confused, but what’s actually going on inside your body with each of these is quite different.
Colds and the flu are both contagious respiratory illnesses that are caused by viruses, but they’re caused by different viruses. The flu comes only from influenza viruses, while colds can come from many different viruses, with rhinovirus being the most common one. As we mentioned in our Back-to-School Health Checklist, rhinovirus is usually the very first bug to spread once the classrooms fill back up in the fall. Colds are so common that adults average two to three colds a year, and kids typically get even more than that.
Allergies are a completely different story. They aren’t caused by a virus at all, and they aren’t contagious. Instead, allergy symptoms happen when your immune system overreacts to something that’s usually harmless in your environment, like pollen, dust mites, mold, or pet dander.
Cold vs Flu: The Biggest Differences to Watch Out For
When it comes to cold vs flu, one of the biggest clues to determine which you have is how quickly you start feeling sick. According to the CDC, flu symptoms usually come on very suddenly, while cold symptoms tend to creep in a bit more gradually over the course of a day or two.
The most common flu symptoms include fever or chills, cough, sore throat, a runny or stuffy nose, muscle and body aches, headaches, and fatigue. Some people, especially kids, may also have vomiting or diarrhea. It’s also important to know that not everyone with the flu will run a fever.
Cold symptoms usually start with a scratchy throat and a runny or stuffy nose, followed by sneezing and a mild cough. Most people start feeling like themselves again within about a week to 10 days. A simple way to think about cold vs flu is this: a cold is a nuisance that usually still lets you push through your day, while the flu tends to knock you down flat and keep you on the couch under a blanket.
That said, the CDC notes that it can be hard, and sometimes impossible, to tell the two apart based on symptoms alone. A quick flu test at the clinic is the only way to know for sure.
Allergies or Cold? How to Tell When It’s Not a Virus
If you’re trying to figure out whether it’s allergies or cold symptoms that you’re dealing with, the first thing to do is to check for any itching. Itchy, watery eyes and an itchy nose or throat are classic allergy signs, and they’re not very common with a cold. Allergies also don’t cause a fever or body aches, and the runny nose that they bring is usually clear and watery.
Timing can be another really helpful clue. A cold usually runs its course in a week or so, but allergy symptoms can stick around for weeks at a time, for as long as you’re around whatever is triggering them. If your symptoms seem to show up at about the same time every year, allergies may be the likely culprit. And you’d be in good company, since about 81 million people in the U.S. live with hay fever.
Fall Allergies in Minnesota
Fall allergies here in Minnesota are mostly caused by ragweed, which blooms in the late summer and keeps going until we get a good, hard frost. The average first freeze in the Twin Cities usually happens in early October, but that doesn’t mean allergy sufferers are in the clear right away. The American College of Allergy, Asthma and Immunology notes that ragweed symptoms can linger even after the pollen is gone, and recommends continuing allergy medication for about two weeks after the first frost.
Then, once we close up the windows for the winter and spend more time inside, indoor triggers like dust mites, pet dander, and mold can start causing symptoms. That’s why so many Minnesotans who feel stuffy all winter long assume they’ve caught a cold that just won’t quit, when it’s really their allergies. If you’ve read our post on spring allergies in Minnesota, you already know that the changing seasons here have a lot to do with how we feel!
Don’t Forget About COVID-19 and RSV
Beyond the usual cold vs flu question, there are a couple of other viruses that tend to circulate around Minnesota this time of year. COVID-19 and RSV can both cause a cough, congestion, sore throat, fever, and fatigue, so they can easily be mistaken for a cold or the flu. The CDC explains that because the flu and COVID-19 share so many of the same symptoms, testing is often needed to confirm which one you have.
RSV usually shows similar symptoms as a mild cold in healthy older kids and adults, but it can be much more serious for infants, toddlers, and older adults. If you have a little one who’s wheezing, breathing fast, or having trouble feeding, it’s important to call your doctor right away.
How Long Is the Flu Contagious?
This is one of the questions we hear the most during flu season, especially from busy parents who are trying to figure out when or not their kids can head back to school. According to the CDC, people with the flu can spread it starting about one day before they even feel sick, and for up to five to seven days after their symptoms start. People are the most contagious during the first three days of their illness, and young children and people with weakened immune systems may be contagious for even longer.
Colds are contagious too, and they spread most easily during the first few days of symptoms. A good rule of thumb for both of these illnesses is to stay home until your symptoms are improving and you’ve been fever-free for at least 24 hours without the help of any fever-reducing medication.
When to See a Doctor for Flu, Cold, or Allergy Symptoms
Most colds and many cases of the flu can be managed at home with plenty of rest, lots of fluids, and a little extra TLC, but there are times when it’s best to check in with your provider. Knowing when to see a doctor for flu symptoms is especially important for anyone who’s at a higher risk of complications.
Call Your Clinic If:
- You think you might have the flu – Prescription antiviral medications work best when they’re started early, so don’t try to tough it out if you’re feeling really sick.
- You’re at higher risk – The CDC says people 65 and older, pregnant women, children under 5 (especially under 2), and people with chronic conditions like asthma, diabetes, or heart disease are at higher risk for serious flu complications. If that’s you or someone you care for, call as soon as symptoms start. Our geriatric care and chronic disease management teams are here to help.
- Your symptoms last longer than 10 days or keep getting worse – A cold that drags on could turn into a sinus infection, an ear infection, or something else that needs treatment.
- Your fever or cough gets better, then comes back worse – This can be a sign of a complication like pneumonia.
- Your allergies are getting in the way of daily life – If over-the-counter medications aren’t helping, or your allergies are keeping you up at night, we can talk through some other options together.
Get Emergency Care Right Away If:
The CDC lists several emergency warning signs that need medical care right away. If you notice any of these, call 911 or go to the nearest emergency room.
- In adults – Difficulty breathing or shortness of breath, persistent pain or pressure in the chest or abdomen, persistent dizziness or confusion, seizures, difficulty urinating, or severe weakness.
- In children – Fast or troubled breathing, bluish lips or face, ribs pulling in with each breath, signs of dehydration (like no urine for 8 hours or no tears when crying), not being alert, or a fever above 104°F that doesn’t come down with fever-reducing medicine.
- In babies younger than 12 weeks – Any fever at all.
For more on caring for your little ones when they’re under the weather, visit our newborn, pediatric, and adolescent care page.
Simple Ways to Stay Healthier This Minnesota Flu Season
- Get your flu shot – The CDC recommends a yearly flu vaccine for everyone 6 months and older. If you haven’t gotten yours yet, it’s not too late, and it’s one of the best ways to keep your whole family protected.
- Wash your hands often – Especially after school pickup, a quick trip to the grocery store, or an afternoon cheering on the kids at the arena.
- Stay home when you’re sick – No matter where you land on the cold vs flu question, keeping your germs at home is one of the kindest things you can do for your coworkers, classmates, and neighbors.
- Keep your home allergy-friendly – Change your furnace filter, wash your bedding in hot water each week, and leave your shoes at the door after raking leaves.
- Get plenty of rest – Good sleep helps keep your immune system strong. Check out our simple sleep health tips for some easy ideas that you can start tonight.
- Take care of dry winter air – A clean humidifier can help soothe a dry nose and throat when the furnace is running around the clock.
How Entira Family Clinics Can Help This Cold and Flu Season
At Entira Family Clinics, we know how quickly a household can go from one sniffly kid to everyone feeling under the weather. We’re a group of family medicine clinics serving patients across the Twin Cities’ East Metro, with clinics in Woodbury, West St. Paul, Vadnais Heights, Shoreview, North St. Paul, Hugo, Highland, the East Side, and Como/Roseville. Our providers take the time to get to know you and your family, so when you call us with a cold vs flu question, you’re talking with people who already know your whole health history.
Not sure if you need to be seen? Our telephone triage nurses are available Monday through Friday from 7 a.m. to 6 p.m. at 651-788-4444. They’ll listen to your symptoms and help you figure out the right next step to take. If you get sick in the evening or over the weekend, our After Hours Care Clinic in North St. Paul is staffed by our own primary care providers and can see you by appointment for things like a cough, fever, sore throat, or sinus congestion. For some concerns, a TeleVisit or E-Visit may also be a more convenient option.
If you or someone in your family isn’t feeling well, or you’d like to get your flu shot, schedule a visit with one of our providers. We’re always here and happy to help you feel more like yourself again.
Frequently Asked Questions
No. When it comes to cold vs flu, they’re caused by completely different viruses, so a cold can’t turn into the flu. However, a cold can sometimes lead to other problems like a sinus or ear infection, and it’s possible to catch the flu right after getting over a cold. If you suddenly start feeling worse with a fever and body aches, it’s a good idea to check in with your provider.
No, allergies don’t cause a fever. If you have a fever along with your sniffles, it’s more likely a virus like a cold, the flu, or COVID-19. Allergies can still leave you feeling tired and run down, though, especially if congestion is affecting your sleep.
Most colds last about 7 to 10 days, with symptoms usually feeling the worst in the first few days. A lingering cough can sometimes hang around a little longer. If your symptoms last more than 10 days without improving, or you start feeling worse instead of better, give us a call.
Not at all! Early fall is the ideal time to get vaccinated, but the CDC recommends getting your flu shot for as long as flu viruses are circulating, and flu season in Minnesota often runs well into spring. Keep in mind that it takes about two weeks after your flu shot for your body to build up its protection.
Antibiotics only work against bacteria, so they won’t help with a cold or the flu, which are both caused by viruses. For the flu, your provider may prescribe an antiviral medication, which works best when it’s started within the first couple of days of symptoms. If a bacterial infection develops, like strep throat or certain sinus infections, antibiotics may be needed.
Yes! Having allergies doesn’t protect you from catching a cold, and it’s common for the two to overlap, especially in the fall. If your usual allergy symptoms suddenly come along with a sore throat, body aches, or a fever, a cold or another virus may have joined the party.
