Flurona symptoms: What are the early signs of flurona?

Medically reviewed by Leslie GreenbergMD
Board-Certified Family Physician
Updated Oct. 27, 2023  •  Published Oct. 19, 2023
Fact Checked
Flurona symptoms: What are the early signs of flurona?

Overview: What does flurona feel/look like?

People use the term “flurona” to describe the unlucky situation when someone contracts both the flu and COVID-19 at the same time. Right now, co-infection is rare. One meta-analysis determined that less than 1% of people diagnosed with COVID-19 also catch a flu infection simultaneously. However, health officials believe that number may increase. Last year, flu cases were down. A more active flu season and new COVID variants might produce a “twindemic” of flu and COVID-19, making flurona a more common experience. 

Both infections have very similar symptoms, which makes it hard to tell them apart. The most common flu symptoms are fever, chills, cough, headaches, muscle aches, tiredness, difficulty breathing, and sore throat. A COVID-19 infection typically feels the same: fever, chills, cough, headaches, muscle aches, difficulty breathing, and fatigue. However, COVID-19 has a few symptoms that are less likely in someone with flu: loss of taste, loss of smell, diarrhea, nausea, or vomiting. Because the symptoms are so similar, often the only way to know if it’s flurona is to be tested for both COVID and influenza.

RELATED: Coronavirus vs. the flu vs. a cold

Key takeaways:

  • Flurona is a rare health condition that can affect anyone regardless of age, sex, race, or ethnicity. Find updated flu statistics here.

  • Early signs of flurona include fever, chills, tiredness, muscle aches, sore throat, dry cough, shortness of breath, headache, congestion, runny nose, and changes in taste or smell.

  • Serious symptoms of flurona, such as difficulty breathing, chest pain, chest pressure, high fever, dizziness, confusion, signs of low oxygen such as blue or pale skin, or worsening of any pre-existing medical conditions, may require immediate medical attention.

  • Flurona is caused by a coronavirus disease 2019 (COVID-19) and influenza co-infection. Everyone is at risk for contracting flu or COVID-19, but healthcare professionals haven’t studied the risk factors for contracting both simultaneously. You may be at risk for developing flurona symptoms if you have not been recently vaccinated for both COVID-19 and influenza.

  • Flurona usually requires a medical diagnosis.

  • Flurona generally requires treatment but depends on the symptoms' severity. Mild or moderate flu and COVID-19 infections resolve in one to two weeks without treatment, but severe COVID-19 infections may require weeks or months of treatment.

  • Treatment of flurona may include supportive care, symptom relief drugs, antiviral medications, and corticosteroids for severe illness. Read more about influenza treatments here

  • Untreated flurona could result in complications like pneumonia, respiratory failure, acute respiratory distress syndrome (ARDS), kidney injury, kidney failure, blood clots, stroke, heart attack, long COVID-19, and neurological or psychiatric complications or death.

  • Use coupons for flurona treatments like Tamiflu (oseltamivir), Xofluza (baloxavir marboxil), Paxlovid (nirmatrelvir-ritonavir), Veklury (remdesivir), and Lagrevio (molnupiravir) to save up to 80%.

What are the early signs of flurona?

Early signs of flurona might be the early signs of flu or COVID-19. Both infections could be caught at later times. The two respiratory viruses have different incubation periods. People with a flu infection typically get sick a few days after exposure. COVID-19 takes two to 14 days after exposure to cause symptoms, but the average is around five days.

The first sign of a flu infection is typically a fever, especially in very young children. The onset of fever and other symptoms can be very rapid:

  • Fever

  • Tiredness or fatigue

  • Body aches

  • Muscle aches

  • Headache

  • Dry cough

The early signs of a COVID-19 infection are more variable. People can have a wide variety of early and later symptoms. Some people may have no symptoms or only very mild symptoms while infected. Unlike flu, a very common early symptom involves changes to smell or taste. In 1 in 10 cases, that’s the first sign of a COVID infection. However, the most common symptoms of a COVID-19 infection can first appear in any order. These common symptoms include:

  • Tiredness

  • Changes in smell or taste

  • Dry cough

  • Fever

  • Muscle pain

  • Headache

  • Shortness of breath

  • Sore throat

Other flurona symptoms

The symptoms of flurona will be a combination of flu and COVID-19 symptoms. Many of these symptoms overlap.

The symptoms of flu include:

  • Fever

  • Chills

  • Tiredness

  • Body aches

  • Headache

  • Dry cough

  • Shortness of breath

  • Sore throat

  • Runny, stuffy nose

  • Ear pain

  • Red, swollen eyes

  • Sneezing

Young children with flu might complain about digestive system issues such as:

  • Nausea

  • Vomiting

  • Diarrhea

  • Stomach upset

  • Stomach pain

In both children and adults, symptoms of COVID-19 infection include:

  • Tiredness

  • Changes in smell or taste

  • Dry cough

  • Fever

  • Chills

  • Muscle pain

  • Headache

  • Shortness of breath

  • Sore throat

  • Diarrhea

  • Nausea

  • Vomiting

  • Congestion

  • Runny nose

  • Sneezing

  • Loss of appetite

  • Abdominal pain

  • Skin rash

Severe flu or COVID infections are marked by symptoms such as:

  • Difficulty breathing

  • Chest pressure

  • Chest pain

  • Changes in mental status, including confusion or dizziness

  • Lethargy 

  • Sleepiness

  • Signs of low oxygen, such as bluish skin, pale skin, clammy skin, or difficulty breathing

RELATED: Flu symptoms 101: is it the flu or something else?

Stages of flurona: How can I tell which one I have?

Both the flu and coronavirus 19 pass through similar stages of infection, but these stages don’t follow the same schedule. COVID-19 tends to be a more drawn-out infection, whereas flu typically resolves in a week or two. 

Incubation stage

Both influenza and COVID-19 infections must replicate in the body before causing symptoms. This presymptomatic stage typically lasts one to four days for flu and two to 14 days for COVID-19, but the average is around five days. Some people with COVID-19 never develop symptoms at all. During incubation, even if asymptomatic, a person with either flu or COVID-19 is contagious.

Acute stage

Flu enters a peak stage about four to five days after exposure. Symptoms come on very quickly. This acute stage lasts for about three days in mild to moderate cases. 

Depending on the variant and the severity of the infection, people with COVID-19 start having symptoms anywhere from two days to two weeks after exposure. Acute COVID-19 symptoms last one to two weeks in mild or moderate cases. However, severe symptoms during flu cases may take six weeks or more to resolve.

For both flu and COVID-19, people showing acute symptoms can spread the infection. People with acute COVID-19 symptoms should isolate for at least 10 days following the onset of symptoms and 20 days for severe illness. 

Recovery stage

For the flu, symptoms begin to decrease about four days after symptoms begin. Usually, they steadily improve over the next three to four days. At this point, people with flu are no longer contagious.

Once symptoms of COVID-19 begin improving, it can take weeks or months for those symptoms to fade completely. Symptoms can sometimes last for years, a condition known as long COVID. Complications of severe flu or COVID-19 illness may be lifelong.

RELATED: What we know about sequelae and lingering COVID-19 symptoms

When to see a doctor for flurona symptoms

Call a healthcare provider if you believe you have COVID-19 symptoms, whether you have the flu or not. The doctor will advise you about what tests you need or if you should visit a clinic in person. If COVID symptoms are severe, such as high fever, difficulty breathing, chest pain, or signs of low oxygen, call 911 or go to an emergency room.

While flu is typically diagnosed based on symptoms and history, COVID-19 requires a rapid antigen test on a nasal swab sample. Rapid flu tests work the same way. In both cases, the test results in 15 to 30 minutes. 

Because COVID-19 and flu can cause pneumonia, the clinician may require chest X-rays, lung ultrasounds, or CT scans to assess the health of the lungs.

RELATED: 8 steps to take if you think you have COVID-19

Complications of flurona

Both flu and COVID-19 have several complications, but coronavirus affects more body areas than influenza. 

The most common complications of a flu infection are:

  • Pneumonia

  • Respiratory failure or acute respiratory distress syndrome (ARDS)

  • Heart inflammation (myocarditis)

  • Swelling of the brain (encephalitis)

  • Inflammation of the muscles (myositis)

  • Kidney failure

Complications of COVID-19 include:

  • Kidney injury and kidney failure

  • Acute respiratory failure and acute respiratory distress syndrome (ARDS) 

  • Organ failure

  • Irregular heartbeats (arrhythmias)

  • Blood clots leading to stroke, heart attack, or pulmonary embolism

  • Long COVID (post-acute COVID-19 syndrome)

  • Neurological or psychiatric complications

RELATED: What groups are at high-risk for flu complications?

How to treat flurona symptoms

In low-risk people, rest, supportive care, and symptom relief are the standard treatment for mild or even moderate cases of flurona. Medications are unnecessary, but Ibuprofen and acetaminophen can relieve fever and pain, while a cough suppressant may provide some cough relief. 

People at a higher risk for complications may be prescribed antiviral drugs that lower the risk of severe infection. Two very different respiratory viruses cause Flu and COVID-19. Coronavirus is a retrovirus whose life cycle is much different from the influenza virus, a DNA virus. The antiviral drugs used to treat influenza, like Tamiflu (oseltamivir), work very differently than FDA approved COVID-19 antivirals like remdesivir and Paxlovid (nirmatrelvir-ritonavir). These medicines cannot be used interchangeably.

Severe illness will require hospitalization. Some people may require supplemental oxygen or mechanical ventilation. People with severe lung problems will be given corticosteroids to reduce immune system swelling and damage to lung tissues.

RELATED: Does the flu shot or Tamiflu help with COVID-19?

Signs flurona is getting better

Flu and most cases of COVID resolve within a few weeks without causing serious problems or complications. For the flu, symptoms should start improving about four days after the onset of symptoms. COVID-19 might take a week or two for symptoms to start improving. One sign of flurona is that the symptoms of one infection, such as the flu, might start improving when the second infection hits. If you have the flu or COVID-19 and symptoms start getting better but then take a turn for the worse, call a doctor for medical advice. 

Most importantly, get vaccinated

Health officials believe the best way to treat flurona is to not get it. Get vaccinated. Both the flu vaccine and the COVID-19 vaccine can prevent infections. They aren’t perfect, but they provide ample security if other preventive measures are taken, such as social distancing, wearing a mask, and avoiding close contact with anyone who’s sick. The flu vaccine can be taken each fall at the beginning of flu season. Each year, the flu vaccine targets the type of flu virus health officials believe will be circulating that year. The two-dose COVID-19 vaccine can be taken at any time of year. Booster COVID-19 vaccines are released on a variable timeline. The current booster vaccine targets all the circulating variants of COVID-19, including the most recent version of the omicron variant.

RELATED: Ask SingleCare: how do I get a discounted or free flu shot?

What’s next? Additional resources for people with flurona symptoms

Test and diagnostics

Treatments

Scientific studies and clinical trials

Medically reviewed by Leslie GreenbergMD
Board-Certified Family Physician

Leslie Greenberg, MD, is a board-certified practicing family physician with more than 25 years of doctoring experience. She was a psychology major at Northwestern University near Chicago, then graduated with an MD from the University of Nevada School of Medicine. She completed her family medicine residency at St. Joseph Hospital in Wichita, Kansas. She has trained more than 350 family medicine resident-physicians, been in private practice, and delivered babies for 22 years.

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