an RNA virus of the family Orthomyxoviridae causing respiratory infection in humans and animals
influenza virus spreads through airborne droplets and contact with contaminated surfaces, producing fever, cough, and muscle pain
three types circulate in humans: influenza A (the source of pandemics), influenza B, and influenza C
the virus undergoes rapid mutation through antigenic drift and shift, requiring annual vaccine reformulation
many plants and essential oils exhibit antiviral activity against influenza, including elderberry, garlic, and eucalyptus