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What do we know about getting the flu and COVID-19 at the same time?

What do we know about getting the flu and COVID-19 at the same time?

This article was published on
January 6, 2022

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“Flurona” is a term popularized by media to describe the condition of being infected with SARS-CoV-2 and influenza at the same time. It is not a new COVID-19 variant, and it is not a separate disease. A person is considered to be co-infected when they are diagnosed with two or more infections at the same time. The presence of multiple diseases in the same person has been observed before, for example, during the 1957 and 1968 influenza pandemics. A similar term, superinfection, is defined by the Centers for Disease Control and Prevention as an infection that is acquired after diagnosis of another infection, especially when caused by antibiotic-resistant microorganisms. The primary difference between co-infection and superinfection is the timing of the second infection.

“Flurona” is a term popularized by media to describe the condition of being infected with SARS-CoV-2 and influenza at the same time. It is not a new COVID-19 variant, and it is not a separate disease. A person is considered to be co-infected when they are diagnosed with two or more infections at the same time. The presence of multiple diseases in the same person has been observed before, for example, during the 1957 and 1968 influenza pandemics. A similar term, superinfection, is defined by the Centers for Disease Control and Prevention as an infection that is acquired after diagnosis of another infection, especially when caused by antibiotic-resistant microorganisms. The primary difference between co-infection and superinfection is the timing of the second infection.

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What our experts say

“Flurona” is a term popularized by media to describe the condition of being infected with SARS-CoV-2 and influenza at the same time. It is not a new COVID-19 variant, and it is not a separate disease. 

A person is considered to be co-infected when they are diagnosed with two or more infections at the same time. The presence of multiple diseases in the same person has been observed before, for example, during the 1957 and 1968 influenza pandemics. A similar term, superinfection, is defined by the Centers for Disease Control and Prevention as an infection that is acquired after diagnosis of another infection, especially when caused by antibiotic-resistant microorganisms. The primary difference between co-infection and superinfection is the timing of the second infection.

According to the World Health Organization, anyone can be co-infected with COVID-19 and influenza, but certain individuals face a higher risk for severe illness from a co-infection. They include older adults, people with a chronic medical condition, people who are immunosuppressed, healthcare workers, pregnant people, or those who recently gave birth. Cases of co-infection have been observed in children and adults, including those who have received both the COVID-19 and seasonal flu vaccines. 

Prevalence data for COVID-19 and influenza co-infection are emerging. Instances have been detected in various countries, including the United States, Israel, Iran, Saudi Arabia, Italy, Switzerland, Spain, Hungary, Brazil, Japan, and China. While the term “flurona” is new, cases of COVID-19 and influenza co-infection in the U.S. have been reported as early as February 2020.

Globally, rates of influenza infection and co-infection with COVID-19 were lower in early 2021, possibly due to stricter coronavirus lockdown measures limiting transmission. However, as lockdown measures have evolved, health officials in the U.S. and Europe are anticipating rises in flu cases as the 2022 winter season progresses, which may impact co-infection rates. 

Coronavirus and influenza share similar symptoms, such as fever, cough, runny nose, and shortness of breath. Experts suspect that SARS-CoV-2 and influenza viruses can interact synergistically to exacerbate symptoms, complications, and prognosis in a co-infected person. Results from animal studies have associated increased morbidity and mortality due to co-infection, however, more outcome data in humans are needed to determine whether concurrent influenza infection increases the risk of disease severity and death from COVID-19. 

“Flurona” is a term popularized by media to describe the condition of being infected with SARS-CoV-2 and influenza at the same time. It is not a new COVID-19 variant, and it is not a separate disease. 

A person is considered to be co-infected when they are diagnosed with two or more infections at the same time. The presence of multiple diseases in the same person has been observed before, for example, during the 1957 and 1968 influenza pandemics. A similar term, superinfection, is defined by the Centers for Disease Control and Prevention as an infection that is acquired after diagnosis of another infection, especially when caused by antibiotic-resistant microorganisms. The primary difference between co-infection and superinfection is the timing of the second infection.

According to the World Health Organization, anyone can be co-infected with COVID-19 and influenza, but certain individuals face a higher risk for severe illness from a co-infection. They include older adults, people with a chronic medical condition, people who are immunosuppressed, healthcare workers, pregnant people, or those who recently gave birth. Cases of co-infection have been observed in children and adults, including those who have received both the COVID-19 and seasonal flu vaccines. 

Prevalence data for COVID-19 and influenza co-infection are emerging. Instances have been detected in various countries, including the United States, Israel, Iran, Saudi Arabia, Italy, Switzerland, Spain, Hungary, Brazil, Japan, and China. While the term “flurona” is new, cases of COVID-19 and influenza co-infection in the U.S. have been reported as early as February 2020.

Globally, rates of influenza infection and co-infection with COVID-19 were lower in early 2021, possibly due to stricter coronavirus lockdown measures limiting transmission. However, as lockdown measures have evolved, health officials in the U.S. and Europe are anticipating rises in flu cases as the 2022 winter season progresses, which may impact co-infection rates. 

Coronavirus and influenza share similar symptoms, such as fever, cough, runny nose, and shortness of breath. Experts suspect that SARS-CoV-2 and influenza viruses can interact synergistically to exacerbate symptoms, complications, and prognosis in a co-infected person. Results from animal studies have associated increased morbidity and mortality due to co-infection, however, more outcome data in humans are needed to determine whether concurrent influenza infection increases the risk of disease severity and death from COVID-19. 

Context and background

Medical experts strongly urge the public to get vaccinated against both COVID-19 and influenza. Vaccination is the most effective way to prevent and protect against severe illness, hospitalization, and death. Receiving both vaccines is necessary because the COVID-19 vaccine does not protect against influenza, and the seasonal influenza vaccine does not protect against COVID-19. 

As both are respiratory infections transmitted by breathing, coughing, talking, singing, or sneezing, health officials also recommend following preventive measures, such as masking, social distancing, and frequent handwashing.

Medical experts strongly urge the public to get vaccinated against both COVID-19 and influenza. Vaccination is the most effective way to prevent and protect against severe illness, hospitalization, and death. Receiving both vaccines is necessary because the COVID-19 vaccine does not protect against influenza, and the seasonal influenza vaccine does not protect against COVID-19. 

As both are respiratory infections transmitted by breathing, coughing, talking, singing, or sneezing, health officials also recommend following preventive measures, such as masking, social distancing, and frequent handwashing.

Resources

  1. Weathering the Omicron Surge, Explaining “Flurona” (Cedars-Sinai)
  2. What is ‘flurona’? Coronavirus and influenza co-infections reported as omicron surges. (The Washington Post)
  3. Co-infection and Syndemics (BioMed Central)
  4. The role of co-infections and secondary infections in patients with COVID-19 (Pneumonia)
  5. COVID-19 and Influenza Co-infection: A Systematic Review and Meta-Analysis (Frontiers in Medicine)
  6. Prevalence and outcomes of co-infection and superinfection with SARS-CoV-2 and other pathogens: A systematic review and meta-analysis (PLOS ONE)
  7. Coinfection with influenza A virus enhances SARS-CoV-2 infectivity (Cell Research)
  8. Increased lethality in influenza and SARS-CoV-2 coinfection is prevented by influenza immunity but not SARS-CoV-2 immunity (Nature Communications)
  9. Diagnosing Flu: Questions & Answers (Centers for Disease Control and Prevention)
  10. Coronavirus disease (COVID-19): Similarities and differences between COVID-19 and Influenza (World Health Organization)
  11. Tracking SARS-CoV-2 variants (World Health Organization)
  12. COVID-19 Testing: What You Need to Know (Centers for Disease Control and Prevention)
  1. Weathering the Omicron Surge, Explaining “Flurona” (Cedars-Sinai)
  2. What is ‘flurona’? Coronavirus and influenza co-infections reported as omicron surges. (The Washington Post)
  3. Co-infection and Syndemics (BioMed Central)
  4. The role of co-infections and secondary infections in patients with COVID-19 (Pneumonia)
  5. COVID-19 and Influenza Co-infection: A Systematic Review and Meta-Analysis (Frontiers in Medicine)
  6. Prevalence and outcomes of co-infection and superinfection with SARS-CoV-2 and other pathogens: A systematic review and meta-analysis (PLOS ONE)
  7. Coinfection with influenza A virus enhances SARS-CoV-2 infectivity (Cell Research)
  8. Increased lethality in influenza and SARS-CoV-2 coinfection is prevented by influenza immunity but not SARS-CoV-2 immunity (Nature Communications)
  9. Diagnosing Flu: Questions & Answers (Centers for Disease Control and Prevention)
  10. Coronavirus disease (COVID-19): Similarities and differences between COVID-19 and Influenza (World Health Organization)
  11. Tracking SARS-CoV-2 variants (World Health Organization)
  12. COVID-19 Testing: What You Need to Know (Centers for Disease Control and Prevention)

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