Flu A vs. Flu B: Which is worse?

When the cold weather hits, trying to avoid the flu can feel like dodging a minefield of coughs and sneezes.

According to the Centers for Disease Control (CDC), about eight percent of the U.S. population gets sick with the flu each season.

The flu is a highly contagious respiratory illness that usually hits hard and fast, and can leave you feeling drained, achy and huddled under a blanket. In worse cases, it can lead to hospitalizations, and even death.

But whether you are hoping to dodge this viral villain entirely or bounce back quickly, knowing how to spot the symptoms and how to protect yourself can make all the difference.

What is the difference between flu A and B?

“There are actually four different varieties of flu” says Susan Wolf, clinical director of OSF OnCall Digital Care. “But the two that affect people the most are flu type A and flu type B.”

Flu A is the most common of the two. It can infect both humans and animals and tends to have more mutations. That means it’s more likely to lead to complications. It tends to hit its peak in the early part of the season – in fall and early winter.

Flu B is less common and only affects humans. It’s less likely to mutate and tends to stay pretty similar every year. It’s more likely to strike later in the season, in late winter and early spring.

“As a virus mutates, it finds new ways to infect us, making it harder for vaccines to keep up,” says Susan. “This makes it trickier to stop it from spreading.”

Flu A vs. Flu B Symptoms

Flu A and flu B both have the same symptoms. However, flu A symptoms tend to feel worse than flu B symptoms.

The most common symptoms are:

• Body aches
• Chills
• Fatigue

• Fever
• Headache
• Sore throat or cough

Sneezing, a runny nose and belly pain are other less common symptoms.

Is there a test for the flu?

Finding out if you have the flu can help rule out other conditions. You can also have other conditions like strep throat or COVID-19 at the same time as the flu.

“Other conditions may be treated differently, like strep throat which requires an antibiotic,” says Susan. “It’s important to get the right diagnosis and treatment to avoid health complications.”

There are at-home kits available to test for influenza A and B, as well as COVID-19 and RSV. You can also be tested at an urgent care or your primary care provider’s office.

Can you get flu A and flu B at the same time?

It is possible to have influenza A and B at the same time or develop one after the other.

“Because they are caused by different strains, the antibodies from one strain doesn’t protect against the other,” says Susan.

Are there flu A and flu B treatment options?

No matter what type of flu you have, there isn’t a quick cure.

But there are options to treat your flu symptoms.

Most of the time, flu symptoms can be managed at home. If your symptoms are severe and you visit your doctor within 48 hours, they can prescribe Tamiflu. This will help lessen the severity of your symptoms.

“Taking alternating doses of Tylenol and Motrin can help relieve a lot of discomfort,” says Susan. “There are also many over-the-counter cold and flu medications that treat respiratory symptoms, like Mucinex.”

In addition to medication, rest and staying hydrated can help you feel better faster.

How long do flu A and flu B last?

While it may feel like an eternity, most flu symptoms typically resolve in 3-7 days.

If you have flu A, some lingering symptoms, like a cough or congestion, may hang around for up to two weeks, especially if you have another condition at the same time.

“These lingering symptoms can mean you are still contagious, so it’s a good idea to avoid contact with others, if possible,” says Susan.

When should I go to the doctor for the flu?

The main thing to watch with flu is your fever and respiratory symptoms.

You should seek care if:

• You have a high temperature (above 102 degrees) that is not improving with the right dose of Tylenol or Motrin.
• You develop a cough or wheezing.

“A common complication we see from flu is symptoms that develop into pneumonia,” says Susan. “This is a serious lung infection that can affect anyone, especially high-risk groups like children younger than 2 and adults older than 65.”

If you’re experiencing mild symptoms, your primary care provider can guide you with treatment options. However, if your symptoms worsen or you have difficulty breathing, persistent high fever or chest pain, it’s best to go to the emergency department immediately.

How to prevent the flu

While there is no way to prevent the flu, you can take steps to lessen the severity of your symptoms if you get it.

“Flu vaccines are available beginning in September all the way through March,” says Susan. “It is still the best proactive defense we have to staying as healthy as possible during flu season.”