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How is influenza transmitted from one person to another?
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influenza
A colored transmission electron micrograph showing influenza viruses (red) at the outer surface of a host cell.
Influenza is a contagious respiratory illness that spreads from person to person primarily through the respiratory tract. Transmission occurs through several key mechanisms:
- Airborne and Droplet Transmission: The virus is spread when an infected individual coughs, sneezes, or talks, releasing infectious particles into the air. These can be inhaled by others as aerosolized particles or land as heavy droplets on the mucous membranes of the eyes, nose, or mouth.123
- Fomite Contact: Influenza viruses can be transmitted through contact with contaminated surfaces or inanimate objects (fomites). If a person touches a contaminated surface and then touches their mouth, nose, or eyes, the virus can gain entry to the body.413
Because influenza viruses are highly contagious, practicing good hand hygiene, wearing masks, and staying home when sick are effective strategies for reducing transmission, particularly during peak flu season. Annual vaccination remains the most effective method for preventing the spread of the disease as viral strains frequently evolve.3