Signs and symptoms of influenza B and ways to prevent it.
(Baonghean.vn) - Influenza B is a respiratory disease caused by a virus. Unlike influenza A virus, which has many disease-causing strains (H1N1, H3N2, H5N1, etc.), influenza B virus has only one strain. Influenza B virus circulates year-round, and transitional weather conditions are favorable for the virus to develop, spread, and cause influenza outbreaks.
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| This type of virus undergoes little change in antigenic structure and can only cause common influenza, which has a simple course and may combine with other influenza viruses to cause respiratory illnesses. |
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| When infected with the virus, the incubation period before flu symptoms appear is 1 to 3 days. The illness itself lasts for about 3 to 5 days. |
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| Everyone is susceptible to the influenza B virus; however, children under 5 years old, pregnant women, the elderly, and people with chronic illnesses are the groups most vulnerable to infection. |
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| - Fever: May be mild or high. - Upper respiratory tract infection: Sore throat, cough, runny nose. - Lower respiratory tract infection: Bronchitis, pneumonia. |






