Table of ContentsView AllTable of ContentsDifferences Between Flu TypesSymptomsCausesDiagnosisTreatmentPrevention
Table of ContentsView All
View All
Table of Contents
Differences Between Flu Types
Symptoms
Causes
Diagnosis
Treatment
Prevention
The most commoninfluenzaviruses in humans are flu A and flu B. Though the two have similar symptoms and are treated in the same way, there aredifferencesbetween them, including how serious they can become in different populations.
This article will discuss the similarities and differences between influenza type A and type B, including who they affect and the types of symptoms. It will also cover causes, diagnosis, treatment, and prevention.
Roos Koole / Getty Images
Differences Between Flu A and Flu B
Flu A and flu B are both types of influenza viruses, but they differ in terms of how common they are, who they tend to affect, and how hard they are to control.
There are several differences between flu A and flu B:
What Is an Epidemic vs. Pandemic?
Symptoms of Flu A and Flu B
Flu A andflu Bhavesimilar symptoms. The severity varies, ranging from mild in many people to severe in some of those who are inhigh-risk groups, including pregnant people, adults over age 64, children under age 5 (especially infants), and people with underlying health conditions.
Influenza in infants is more likely to be flu A, while flu B is common in school-age children.In most healthy children, both flu A and B have mild to moderate symptoms. But in children under age 5, the symptoms of flu B can be more serious.In adults, flu A can be more severe.
Flu symptoms for both A and B tend to begin with a sudden onset of fever and thenprogressto include other symptoms.
Other early symptoms include:
When young children acquire influenza, they may experience nausea, vomiting, or diarrhea in addition to respiratory symptoms.
Flu symptoms generallylast from a few days to about a week or two. But in some people in high-risk groups, the flu can be serious enough to require hospitalization. In some cases, it can befatal.
Deaths in the United States from influenza from 2010 to 2020 ranged from 12,000 to 52,000 a year. Hospitalizations associated with influenza ranged from 140,000 to more than 700,000 per year over the same period.
Causes of Flu A and Flu B
Flu A viruses mutate (change genetically) more frequently than flu B. New subtypes of flu A can emerge through mutations and cross to humans from animals.This can result in pandemics of flu A, which are not seen with flu B.
Flu viruses generally cause more illness during flu season, which is in the fall and winter in each hemisphere. The subtypes that are circulating change from year to year. Flu A is usually more prominent earlier in the flu season, while flu B emerges later.
Both flu A and B are very contagious, and people are most likely to transmit them to others during the first three to four days after starting to feel ill, though sometimes healthy adults can infect others a day before their symptoms start.
Diagnosing Flu A vs. Flu B
Your healthcare provider may make adiagnosisbased on your symptoms.If you are at high risk or having severe symptoms, they may choose to test for the flu and confirm that is the cause. Some types of tests can also identify whether you have type A or B.
The information as to the type or strain of flu is important from a public health perspective but is unlikely to affect your treatment plan. Your provider may be able to do the test on-site, or they may send it to a laboratory. Common types of flu tests include:
Treating Flu A and Flu B
Flu A and flu B are treated in the same way. Many people recover from the flu on their own. If your symptoms are bothersome, check with your healthcare provider about the following:
Home remedies that may help include honey for a sore throat and inhaling steam to clear your stuffy nose. Check with a healthcare provider before you try home remedies.
Flu A and flu B are similar in their response to antiviral medications.Antiviral flu medications work best if you take them within 48 hours of the onset of symptoms.If you need further care or hospitalization, follow your healthcare provider’s recommendations.
What to Do When You Get the Flu
Preventing Influenza
The Centers for Disease Control and Prevention (CDC) recommends that people 6 months or older receive the fluvaccineeach year. Children age 6 months to 8 years may need two injections.
The vaccine protects against both flu A and flu B. It contains strains that are predicted to be circulating, two flu A viruses and one flu B.
Otherprecautionsthat can help prevent catching or transmitting the flu include:
Summary
Flu A and B are different types of the influenza virus and affect adults and children differently. Flu A is more common overall and can be more serious in adults. Flu B is more common in children and may be more serious in young children.
Both types are very contagious and most easily transmitted during the first few days after becoming ill. The symptoms are similar, though they can vary in intensity. You may develop a fever quickly and feel achy and tired. Respiratory symptoms develop later.
Flus A or B can affect certain populations more seriously, so call a healthcare provider if you are pregnant, over age 64, have a weakened immune system, or have a chronic medical illness, such as asthma, heart disease, or diabetes.
17 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.Bhat YR.Influenza B infections in children: A review.World J Clin Pediatr. 2020;9(3):44-52. doi:10.5409/wjcp.v9.i3.44Columbia University Mailman School of Public Health.Epidemic, endemic, pandemic: What are the differences?Centers for Disease Control and Prevention.Types of influenza viruses.University of Minnesota.Early-season influenza B dominance—why it’s hard on kids.World Health Organization.Influenza (seasonal).Penn Medicine.Flu (influenza).Centers for Disease Control and Prevention.Clinical signs and symptoms of influenza.Centers for Disease Control and Prevention.About estimated flu burden.Centers for Disease Control and Prevention.Key facts about Influenza (flu).MedlinePlus.Flu (influenza) test.Centers for Disease Control and Prevention.Diagnosing flu.Centers for Disease Control and Prevention.Overview of influenza testing methods.U.S. Food and Drug Administration.FDA authorizes first over-the-counter at-home test to detect both influenza and COVID-19 viruses.American Academy of Pediatrics.Using over-the-counter medicines with your child.Centers for Disease Control and Prevention.What you should know about flu antiviral drugs.Centers for Disease Control and Prevention.Inactivated influenza VIS.Centers for Disease Control and Prevention.Healthy habits to protect against the flu.
17 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.Bhat YR.Influenza B infections in children: A review.World J Clin Pediatr. 2020;9(3):44-52. doi:10.5409/wjcp.v9.i3.44Columbia University Mailman School of Public Health.Epidemic, endemic, pandemic: What are the differences?Centers for Disease Control and Prevention.Types of influenza viruses.University of Minnesota.Early-season influenza B dominance—why it’s hard on kids.World Health Organization.Influenza (seasonal).Penn Medicine.Flu (influenza).Centers for Disease Control and Prevention.Clinical signs and symptoms of influenza.Centers for Disease Control and Prevention.About estimated flu burden.Centers for Disease Control and Prevention.Key facts about Influenza (flu).MedlinePlus.Flu (influenza) test.Centers for Disease Control and Prevention.Diagnosing flu.Centers for Disease Control and Prevention.Overview of influenza testing methods.U.S. Food and Drug Administration.FDA authorizes first over-the-counter at-home test to detect both influenza and COVID-19 viruses.American Academy of Pediatrics.Using over-the-counter medicines with your child.Centers for Disease Control and Prevention.What you should know about flu antiviral drugs.Centers for Disease Control and Prevention.Inactivated influenza VIS.Centers for Disease Control and Prevention.Healthy habits to protect against the flu.
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.
Bhat YR.Influenza B infections in children: A review.World J Clin Pediatr. 2020;9(3):44-52. doi:10.5409/wjcp.v9.i3.44Columbia University Mailman School of Public Health.Epidemic, endemic, pandemic: What are the differences?Centers for Disease Control and Prevention.Types of influenza viruses.University of Minnesota.Early-season influenza B dominance—why it’s hard on kids.World Health Organization.Influenza (seasonal).Penn Medicine.Flu (influenza).Centers for Disease Control and Prevention.Clinical signs and symptoms of influenza.Centers for Disease Control and Prevention.About estimated flu burden.Centers for Disease Control and Prevention.Key facts about Influenza (flu).MedlinePlus.Flu (influenza) test.Centers for Disease Control and Prevention.Diagnosing flu.Centers for Disease Control and Prevention.Overview of influenza testing methods.U.S. Food and Drug Administration.FDA authorizes first over-the-counter at-home test to detect both influenza and COVID-19 viruses.American Academy of Pediatrics.Using over-the-counter medicines with your child.Centers for Disease Control and Prevention.What you should know about flu antiviral drugs.Centers for Disease Control and Prevention.Inactivated influenza VIS.Centers for Disease Control and Prevention.Healthy habits to protect against the flu.
Bhat YR.Influenza B infections in children: A review.World J Clin Pediatr. 2020;9(3):44-52. doi:10.5409/wjcp.v9.i3.44
Columbia University Mailman School of Public Health.Epidemic, endemic, pandemic: What are the differences?
Centers for Disease Control and Prevention.Types of influenza viruses.
University of Minnesota.Early-season influenza B dominance—why it’s hard on kids.
World Health Organization.Influenza (seasonal).
Penn Medicine.Flu (influenza).
Centers for Disease Control and Prevention.Clinical signs and symptoms of influenza.
Centers for Disease Control and Prevention.About estimated flu burden.
Centers for Disease Control and Prevention.Key facts about Influenza (flu).
MedlinePlus.Flu (influenza) test.
Centers for Disease Control and Prevention.Diagnosing flu.
Centers for Disease Control and Prevention.Overview of influenza testing methods.
U.S. Food and Drug Administration.FDA authorizes first over-the-counter at-home test to detect both influenza and COVID-19 viruses.
American Academy of Pediatrics.Using over-the-counter medicines with your child.
Centers for Disease Control and Prevention.What you should know about flu antiviral drugs.
Centers for Disease Control and Prevention.Inactivated influenza VIS.
Centers for Disease Control and Prevention.Healthy habits to protect against the flu.
Meet Our Medical Expert Board
Share Feedback
Was this page helpful?Thanks for your feedback!What is your feedback?OtherHelpfulReport an ErrorSubmit
Was this page helpful?
Thanks for your feedback!
What is your feedback?OtherHelpfulReport an ErrorSubmit
What is your feedback?
