Influenza viruses are viruses that cause influenza, a contagious respiratory infection affecting humans and some other animals.
Influenza viruses belong to the family Orthomyxoviridae. Influenza A and influenza B viruses are the principal causes of seasonal influenza in humans, while influenza C usually causes milder illness and influenza D primarily affects cattle and is not considered an established cause of human disease.
Influenza viruses continually undergo genetic changes, which contribute to the emergence of new strains and the need for ongoing surveillance and periodic updating of influenza vaccines.
QUICK FACT
Influenza viruses are different from the viruses that cause the common cold. Many different viruses can cause cold symptoms, whereas influenza is caused by influenza viruses.
COMMONLY CONFUSED WITH
Rhinovirus: Rhinoviruses are a major cause of the common cold; influenza viruses cause influenza.
SEE ALSO
- Influenza
- Viral infection
- Respiratory Infection
- Common cold
- Antiviral