Can I Get a Flu Shot If I Have COVID?

Getting a flu shot while you have COVID-19 is not off-limits, but the standard medical advice is to wait until your acute illness has resolved. The Advisory Committee on Immunization Practices (ACIP) recommends that clinicians consider delaying influenza vaccination until patients with suspected or confirmed COVID-19 are no longer acutely ill.¹ That guidance is not a hard prohibition; it is a practical recommendation shaped by several overlapping concerns, from how well your immune system can respond to a vaccine while already fighting an infection, to the risk of exposing others at a vaccination site.

What “No Longer Acutely Ill” Actually Means

The phrase “no longer acutely ill” can feel vague, but it maps onto straightforward criteria. You should be past the worst of your symptoms: no fever without the help of fever-reducing medication, improving respiratory symptoms, and generally feeling functional. You do not need to test negative for SARS-CoV-2 before getting your flu shot, though you should be past the point of highest contagiousness, which for most people is the first several days after symptom onset.

This is the same general principle that applies to any vaccination during illness. If you showed up for a flu shot with a high fever from strep throat, your provider would likely tell you to come back when you felt better. COVID is not treated differently in this respect. The concern is partly about vaccine effectiveness: your immune system is already mobilized against one pathogen, and there is at least a theoretical question about whether it can mount the best possible response to a vaccine antigen at the same time. The other concern is more practical and has to do with sorting out side effects. A flu shot can cause a low-grade fever and body aches. If you are already running a fever from COVID, adding vaccine side effects on top can make it harder for you and your doctor to tell what is causing what.

What About Going to a Pharmacy or Clinic While Contagious?

Even if you feel only mildly sick and want to get your flu shot out of the way, there is the matter of everyone else. Walking into a pharmacy or doctor’s office while still infectious with SARS-CoV-2 exposes staff and other patients. Research tracking COVID transmission in outpatient settings found that standard precautions like surgical masks and hand hygiene provide strong protection for healthcare workers, with one study finding zero confirmed transmissions among over 300 workers who had contact with infected outpatients.² But that study involved settings where standard infection control was rigorously followed. A crowded pharmacy line is not quite the same environment. The simplest path is to wait until your isolation period is over before heading out for a vaccination.

During the early pandemic years, many health systems addressed this tension by expanding vaccination options that reduced contact: drive-through clinics, outdoor vaccination sites, and extended pharmacy hours. Multiple countries adopted these alternative delivery models specifically to keep flu vaccination rates up while minimizing COVID exposure risks.³ Some of these options remain available, though their prevalence varies by region.

Why Getting the Flu Shot Still Matters After COVID

A question that sometimes lurks behind “can I get a flu shot while I have COVID” is whether the flu shot is even worth it after a bout of COVID. The answer is emphatically yes, and the research on co-infections helps explain why. Being infected with both SARS-CoV-2 and influenza at the same time is significantly worse than having either alone. A meta-analysis found that people co-infected with flu and COVID faced roughly double the odds of ICU admission and more than double the odds of needing mechanical ventilation compared to those with COVID alone.⁴

Animal research has added detail to this picture. In mouse models, co-infection with SARS-CoV-2 and influenza A not only prolonged the infection period for both viruses but also impaired the body’s ability to produce neutralizing antibodies against each one. Co-infected animals showed severe drops in certain immune cells in the blood, elevated inflammatory markers, and higher mortality than animals infected with just one virus.⁵ In other words, having both infections at once creates a kind of immunological traffic jam where the body struggles to fight either one effectively. Getting a flu shot after recovering from COVID is one of the most straightforward ways to reduce that co-infection risk heading into the next flu season.

Giving the Flu Shot and COVID Vaccine at the Same Time

A related and common question is whether you can receive a flu vaccine and a COVID vaccine at the same visit. This is distinct from getting vaccinated while actively sick with COVID, but the two questions often get tangled together. The evidence here is reassuring. A large randomized trial in the UK found that giving a COVID vaccine (either the AstraZeneca or Pfizer-BioNTech version) alongside an age-appropriate flu vaccine raised no safety concerns, produced mostly mild or moderate side effects, and preserved antibody responses to both vaccines.⁶ Seroconversion rates, a measure of whether the vaccine successfully provoked an immune response, ranged from 79% to 100% across the different vaccine combinations when given together, similar to the rates seen when the COVID vaccine was given alone.

Another study examining a protein-based COVID vaccine found that co-administration left the flu vaccine immune response unchanged, though it noted a slight reduction in antibody responses to the COVID vaccine component. Even with that small dip, vaccine efficacy remained high.⁷ And intriguingly, at least one study found that giving the two vaccines concurrently actually boosted certain antibody responses against SARS-CoV-2 compared to giving them separately, with higher levels at both peak immunogenicity and six months later.⁸ The practical takeaway is that if you are due for both shots, getting them at the same visit is safe and can actually simplify things.

Children and COVID-Timed Flu Shots

Guidance for children follows the same general principle as for adults but with slightly more specific language. The American Academy of Pediatrics has consistently recommended that children with confirmed COVID-19 can receive the influenza vaccine once the acute illness has resolved.⁹ In more recent seasons, the AAP added nuance: children should generally defer routine vaccination visits, including flu shots, until they meet criteria for ending isolation and are no longer moderately to severely ill. But if a child is already in a healthcare setting for another reason and their COVID illness is mild, they can go ahead and receive the flu vaccine at that visit.¹⁰

This is a practical distinction that matters for parents. If your child has a mild case of COVID and happens to be at the pediatrician for something else, there is no medical reason to miss the opportunity. But making a special trip to a pharmacy while your child is still symptomatic and potentially contagious is a different calculation. The vaccine itself is not harmful during mild illness; the issue is timing, logistics, and community courtesy.

Immunocompromised Patients

People with weakened immune systems face a particular bind. They are more vulnerable to severe outcomes from both COVID and influenza, but they also tend to have weaker responses to vaccines. The Infectious Diseases Society of America’s 2025 guidelines strongly recommend timely flu, COVID, and RSV vaccination for immunocompromised patients, endorsing co-administration of these vaccines and providing guidance on optimal timing relative to immunosuppressive therapies and transplant procedures.¹¹

The guidelines acknowledge research gaps around how durable vaccine protection is in these patients, especially for those receiving therapies that deplete B cells or who are in the early period after organ transplant. For someone who is immunocompromised and currently has COVID, the same basic principle applies: wait until the acute illness passes, then get vaccinated as soon as reasonably possible. Because these patients may have prolonged COVID courses, the window for “feeling better but still needing the flu shot” can stretch longer than it does for healthier individuals. Talking with a specialist about the right timing relative to treatment cycles matters more here than for the general population.

Telling Flu and COVID Apart Before Your Appointment

One complication in all of this is knowing what you actually have. Flu and COVID share many symptoms: fever, cough, body aches, fatigue, sore throat. If you assume you have COVID because a home test was positive, the guidance is clear enough. But if you feel sick and are not sure whether it is flu, COVID, a cold, or something else, testing helps clarify the picture. Home rapid tests for COVID are widely available and reasonably accurate for symptomatic individuals. Home rapid tests for influenza also exist, though their sensitivity is more limited. One study of an at-home flu test found sensitivity in the range of 57% to 67% depending on flu type and timing, meaning these tests miss a fair number of actual flu cases while being quite specific when they do come back positive.¹²

If you are trying to decide whether to go get a flu shot while feeling under the weather, the simplest approach is to test for COVID at home. If positive, wait until you recover. If negative and you feel mostly functional with only mild symptoms, most providers will still give you the flu shot. The bar is not “feeling perfect.” It is “not acutely ill with a moderate to severe infection.”

The Pandemic’s Lingering Effect on Flu Vaccination Rates

There is an irony worth noting. The pandemic initially made people more interested in flu shots. During the 2020–2021 season, flu vaccination rates actually ticked up in several countries as public awareness of respiratory illness peaked. But that bump did not last. A large U.S. study using a nationwide database found that flu vaccination rates rose by about two percentage points during the pandemic period compared to pre-pandemic levels, then dropped by more than six percentage points after the pandemic ended.¹³ The declines hit younger adults and certain racial groups especially hard.

A separate multi-year analysis found that post-pandemic flu vaccination rates were falling by more than two percentage points per year, with coverage among adults 65 and older dropping from about 65% to 49% over the study period.¹⁴ The pattern in Canada looked somewhat different: a temporary dip during the 2021–2022 season followed by a return to pre-pandemic levels in subsequent years.¹⁵

The term researchers use for this pattern is “vaccine fatigue,” and it appears to be a real phenomenon in several countries. After years of pandemic-related public health messaging, some portion of the population seems to have tuned out vaccination recommendations altogether, including for flu. This makes the individual decision to get your flu shot after recovering from COVID more consequential, not less. The collective protection that high vaccination rates provide is thinner than it was a few years ago, which means your personal flu shot carries a bit more weight in keeping both you and the people around you protected.

A Common Misconception About Natural Immunity Crossover

Some people wonder whether having had COVID gives them any protection against the flu, or vice versa. It does not. SARS-CoV-2 and influenza viruses are fundamentally different pathogens. They belong to different virus families, use different mechanisms to enter cells, and provoke immune responses that do not cross-react in any meaningful protective way. Having survived a bout of COVID does nothing for your flu risk. If anything, the co-infection data suggests the opposite: the immune disruption caused by one virus can make you more vulnerable to severe outcomes if you catch the other. The mouse studies mentioned earlier showed that co-infected animals actually produced fewer virus-specific antibodies against each pathogen than animals infected with just one, suggesting the immune system gets stretched thin rather than broadly fortified.⁵

This misconception sometimes merges with a broader sense that “I’ve been sick enough already this year, I don’t need another shot.” Being recently ill is an understandable reason to feel reluctant, but it is not a medical reason to skip the flu vaccine. Once you have recovered from COVID, your immune system is no longer preoccupied, and it is ready to respond to a vaccine antigen normally. The optimal window is before flu season peaks in your area, so getting vaccinated promptly after recovering from COVID, rather than putting it off indefinitely, is the better strategy.