What Flu Symptoms Looks Like Day by Day, According to Doctors
Plus, why the first few days are so important.
This time of year, it can seem like sickness is lurking around every corner. Colds, COVID, RSV, the flu … it’s no wonder why when someone coughs in public, they’re often met with the side-eye. If you do start feeling lousy, it can be tricky to pinpoint exactly what’s wrong since many types of illnesses have overlapping symptoms.
When it comes to the flu, doctors say that there are some telltale symptoms to be aware of. Curious as to what they are and when you can expect to feel better if you come down with it? Keep reading to see a day-by-day breakdown.
Related: Should You Get the Flu Shot and COVID Booster at the Same Time? Doctors Share the Pros and Cons
The Main Ways People Get the Flu
Dr. Richard Watkins, MD, an infectious disease physician and professor of medicine at the Northeast Ohio Medical University, explains that the flu is a virus that is mainly transmitted through the air when people cough, sneeze or speak. “It can also spread from contaminated surfaces,” he adds.
Dr. John Whyte, MD, MPH, the Chief Medical Officer of WebMD, echoes this, saying, “The flu is a respiratory virus, which means it spreads mainly by droplets that result when an infected person coughs or sneezes.” He adds that these droplets can land in the mouths or noses of people who are nearby—usually within about six feet away—or possibly be inhaled into the lungs.
Related: So You Feel a Cold Coming On—Here's Everything You Can Do To Stop It In Its Tracks
If you’ve gotten the flu shot, both doctors say that that lowers your risk of getting the flu by between 40 and 60 percent—at least when the strain in the vaccine matches the one in circulation. If you do still get the virus, both say that your symptoms will be milder and you’ll feel better quicker than if you didn’t get the flu vaccine. “People who are vaccinated might not get any symptoms, or they may have mild symptoms that last only a day or two,” Dr. Watkins says.
Skipped the flu shot this year? Here’s a run-down of the timeline you can expect from the virus. Again, if you did get the flu shot but you get the flu, you can expect to experience symptoms that are less severe and they will not last as long.
A Day-by-Day Timeline of the Flu
Days 1 and 2
“Despite what some people think, it's not as if someone sneezes on you and the next day you develop symptoms,” Dr. Whyte says. He explains that it takes about 48 hours for symptoms to develop and be noticeable. “Usually, you are contagious from the time you get infected, which is why the flu spreads so quickly,” he says.
At first, Dr. Whyte says that the flu symptoms are mild. He says that someone may feel a bit warm, but they don’t have a fever. “You’ll be slightly congested and start feeling tired and get a few body aches, which you might attribute to something else,” he says.
By day two, Dr. Whyte says someone with the flu experiences a lot more congestion and generally feels worse than they did the previous day. “Usually, someone will develop a low-grade fever, around 100℉,” he says. He adds that, accompanied with the congestion, is a cough that’s in full force. Other super unpleasant symptoms that Dr. Whyte says pop up on day two are feeling tired, yet having trouble sleeping, and losing your appetite. “By now, you realize you may have caught something,” he says.
Days one and two are super critical for taking action that can help you recover quicker. “The key for the first 48 hours of symptoms is that this is the timeframe that doctors use to prescribe medication, like Tamiflu. After 48 or 72 hours, many doctors won't prescribe it since the benefit is less. That's why if you are concerned about the flu, get tested early,” Dr. Whyte says.
Days 3 and 4
Day two of the flu is very unpleasant, and unfortunately, so is day three. “People often say they feel as if they were hit by a bus. It's typically the worst day,” Dr. Whyte says. During this time, you can expect the same symptoms as before, just amplified.
According to Dr. Watkins, having a fever, chills, coughing, a sore throat, runny or stuffy nose, muscle or body aches, headaches, and fatigue can all be expected. “Some people may have vomiting and diarrhea, though this is more common in children than adults,” he adds.
On day four, both doctors say many people start to feel at least a little bit better. It’s the start of the turning point. “Typically, the fever resolves without medication,” Dr. Whyte says. Appetite, he says, starts returning too. Congestion and fatigue, however, are likely still around.
Days 5 - 9
Both doctors say that once someone hits day five, they’re typically feeling much better. Symptoms continue to be less severe on days six and seven too. Dr. Whyte says that coughing is typically the symptom that sticks around the longest, but it should be getting less frequent as time goes on. You should feel completely better on the ninth day after contracting the flu virus.
As you can see, coming down with the flu is absolutely not fun. It bears repeating that getting the flu vaccine can decrease your odds of contracting the virus and can also make symptoms less severe if you do get it. “People also should wash their hands frequently, especially after returning from being outside their homes. And avoid touching your face as much as possible,” Dr. Watkins says.
Yes, it’s true that germs are pretty much everywhere this time of year. But now that you know the hallmark symptoms of the flu, you can take action during those first critical days if you do come down with it. That way, you can bounce back faster which is good news for both you and everyone else too.
Next up, see what nine myths about the flu doctors wish everyone would stop believing.
Sources
Dr. Richard Watkins, MD, infectious disease physician and professor of medicine at the Northeast Ohio Medical University
Dr. John Whyte, MD, MPH, Chief Medical Officer of WebMD
