Sep 26, 2025 · There are four types of influenza viruses: A, B, C, and D. Influenza A and B viruses cause seasonal epidemics of disease in people (known as flu season) almost every winter in the …

Jan 23, 2025 · Three types of flu viruses affect humans: types A, B, and C. Type A and B cause the annual influenza epidemics that have up to 20% of the population sniffling, aching, coughing, and …

Jan 22, 2025 · Influenza A and influenza B are the main strains of flu virus. Type A causes more cases, more severe illness and infects many species. Type B only infects humans.

There are four types of influenza virus: types A, B, C, and D. Aquatic birds are the primary source of influenza A virus (IAV), which is also widespread in various mammals, including humans and pigs.

Feb 28, 2025 · There are 4 types of influenza viruses, types A, B, C and D. Influenza A and B viruses circulate and cause seasonal epidemics of disease. Influenza A viruses are further classified into …

Nov 21, 2025 · Key takeaways: There are four main strains or types of influenza virus: A, B, C, and D. Influenza A and B viruses cause the flu season each year. Flu virus strains are always changing. …

Influenza viruses cause the flu. There are four types of flu viruses: influenza A, B, C and D. 6 The viruses tend to change in two ways: antigenic drift and antigenic shift. Small gene mutations cause …

Jul 21, 2023 · Influenza is caused by three types of RNA viruses called influenza types A, B and C (considered different genera), which all belong to the family Orthomyxoviridae.

This topic portal, hosted by the Centers for Disease Control and Prevention (CDC), provides an overview of the different types of influenza viruses, including influenza A, B, C, and D.

While there are technically 4 types of flu, there are also different subtypes. To start, let’s go over the four different types of flu viruses – A, B, C, and D: Influenza A: Influenza A viruses can be found in many …