Key TakeawaysThe incubation period for the flu is the time between when a person is infected and when they start feeling sick.The incubation time for the flu ranges from 1 to 4 days, with an average of 2 days.Experts are predicting a more severe flu season in 2022, but getting a flu vaccine and taking antivirals soon after you get sick can help.

Key Takeaways

The incubation period for the flu is the time between when a person is infected and when they start feeling sick.The incubation time for the flu ranges from 1 to 4 days, with an average of 2 days.Experts are predicting a more severe flu season in 2022, but getting a flu vaccine and taking antivirals soon after you get sick can help.

In the United States,flu seasontypically starts in October and peaks in February. Health experts are predicting that the 2022–2023 flu season could be more severe than the last couple of years when COVID-19 precautions helped lessen the burden of influenza.

That said, a bad flu season is not completely different from a typical one. While it’s true different flu strains go around from year to year (and some are “worse” than others), there are some aspects of the flu that tend to be consistent in any flu season.

One example? Theincubation periodfor the flu.Dean Winslow, MD, a professor of medicine in the Divisions of Hospital Medicine and Infectious Diseases at Stanford University, told Verywell that the incubation period is the time from when a person is exposed to the flu virus to when they start to have symptoms.

According to Winslow, the flu’s incubation period is 1 to 4 days with an average of 2 days, and it shouldn’t be different year to year.

Winslow also explained that the incubation period for the flu and COVID do not seem to vary much depending on the strain. Whatcanvary is how sick people get—and we’ve seen that with both the flu and COVID.

Study: Newer COVID-19 Variants Have Shorter Incubation Periods

Why Does Flu Incubation Time Matter?

It’s hard for experts to predict which flu strains will be the most prominent during a given season, but understanding the incubation period helps them guide the public in preventing severe illness, decreasing symptoms, and slowing the spread of the virus.

Infectious disease experts use incubation periods in the surveillance, control, and setting of quarantine guidelines for contagious illnesses like the flu, COVID, and even the common cold.

According to the Centers for Disease Control and Prevention (CDC), the flu incubation period is typically consistent across all strains, but the periods of contagiousness can vary depending on a person’s age and risk factors:

Brace Yourself. Flu Season Is Coming Fast

Can You Interrupt the Flu Incubation Period?

In some cases, there are steps you can take in the time between when you were exposed to the flu virus but haven’t started to feel sick yet that could make a difference in how the illness plays out.

For example, Winslow said that certainat-risk people—such as older adults in nursing homes where a flu outbreak is happening—“can be given prophylacticantiviral medicationssuch as Tamiflu (oseltamivir) or Xofluza (baloxavir).”

According to Winslow, these medications are “most effective if given earlier in the incubation period,” but they can still help with “reducing the severity of infection and duration of symptoms even if given in the first 48 hours after symptoms have started.”

The CDC lists four antivirals available to treat suspected or confirmed cases of uncomplicated flu symptoms and also decrease illness severity:

How Flu Shots Work and Why They Sometimes Don’t

Why Is This Year’s Flu Season Going to Be Worse?

There are several factors that can make a flu season more severe, including:

In a recent press release,William Schaffner, MD, the medical director for the National Foundation for Infectious Diseases (NFID), said that based on what experts have seen in the Southern Hemisphere, the flu has the potential to hit us hard this year.

“[But] on a positive note, we have more preventive behaviors in our toolbox than we did before the COVID-19 pandemic,” Schaffner added. “We are more accustomed to wearing masks and staying home when sick.”

Experts Say You Really Need a Flu Shot This Year

How to Stay Healthy This Flu Season

In any flu season, but especially ahead of a bad one, getting a flu shot is one of the first and most important steps that you can take to protect yourself and the people around you.

In partnership with the NFID, the CDC recently rolled out its 2022-2023 Flu Vaccination Campaign in which it stressed the importance of getting a flu vaccine to help slow the spread and severity of the illness.

The campaign also announced three specific flu vaccines that are preferentiallyrecommended for people aged 65 and older. These vaccines have been shown to be more effective for high-risk populations:

If You’re Over 65, a High-Dose Flu Shot May Offer Best Protection

In addition to getting vaccinated, the CDC alsorecommends taking other practical stepsto prevent the flu such as:

What This Means For You

7 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Centers for Disease Control and Prevention.Flu season.Gussow AB, Auslander N, Wolf YI, Koonin EV.Prediction of the incubation period for COVID-19 and future virus disease outbreaks.BMC Biol. 2020;18(1):186. doi:10.1186/s12915-020-00919-9Centers for Disease Control and Prevention.Key facts about influenza (flu).Centers for Disease Control and Prevention.Influenza antiviral medications: summary for clinicians.Centers for Disease Control and Prevention.Vaccine effectiveness: how well do flu vaccines work?National Foundation for Infectious Diseases.2022 National survey: attitudes about influenza and pneumococcal disease, and the impacts of COVID-19.Centers for Disease Control and Prevention.2022-2023 Flu vaccination campaign kickoff.

7 Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Centers for Disease Control and Prevention.Flu season.Gussow AB, Auslander N, Wolf YI, Koonin EV.Prediction of the incubation period for COVID-19 and future virus disease outbreaks.BMC Biol. 2020;18(1):186. doi:10.1186/s12915-020-00919-9Centers for Disease Control and Prevention.Key facts about influenza (flu).Centers for Disease Control and Prevention.Influenza antiviral medications: summary for clinicians.Centers for Disease Control and Prevention.Vaccine effectiveness: how well do flu vaccines work?National Foundation for Infectious Diseases.2022 National survey: attitudes about influenza and pneumococcal disease, and the impacts of COVID-19.Centers for Disease Control and Prevention.2022-2023 Flu vaccination campaign kickoff.

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

Centers for Disease Control and Prevention.Flu season.Gussow AB, Auslander N, Wolf YI, Koonin EV.Prediction of the incubation period for COVID-19 and future virus disease outbreaks.BMC Biol. 2020;18(1):186. doi:10.1186/s12915-020-00919-9Centers for Disease Control and Prevention.Key facts about influenza (flu).Centers for Disease Control and Prevention.Influenza antiviral medications: summary for clinicians.Centers for Disease Control and Prevention.Vaccine effectiveness: how well do flu vaccines work?National Foundation for Infectious Diseases.2022 National survey: attitudes about influenza and pneumococcal disease, and the impacts of COVID-19.Centers for Disease Control and Prevention.2022-2023 Flu vaccination campaign kickoff.

Centers for Disease Control and Prevention.Flu season.

Gussow AB, Auslander N, Wolf YI, Koonin EV.Prediction of the incubation period for COVID-19 and future virus disease outbreaks.BMC Biol. 2020;18(1):186. doi:10.1186/s12915-020-00919-9

Centers for Disease Control and Prevention.Key facts about influenza (flu).

Centers for Disease Control and Prevention.Influenza antiviral medications: summary for clinicians.

Centers for Disease Control and Prevention.Vaccine effectiveness: how well do flu vaccines work?

National Foundation for Infectious Diseases.2022 National survey: attitudes about influenza and pneumococcal disease, and the impacts of COVID-19.

Centers for Disease Control and Prevention.2022-2023 Flu vaccination campaign kickoff.

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