Influenza

Transmission and Identification: Birds are the main reservoir of the virus, and transmission usually occurs through contact with airborne droplets of bodily fluids from coughing or sneezing. Those over the age of 65 or those fighting a chronic illness are at the highest risk of infection and death; most mortalities are associated with a secondary infection with another pathogen. After an incubation period of 18 to 72 hours, infection can last seven to ten days followed by rapid recovery. Symptoms include: fever, fatigue, headache, muscle aches, sore throat, dry cough, and nasal congestion.

Identifying Influenza type A can be difficult since many other pathogens initially cause similar symptoms. In order to identify the virus, viral cultures derived from mucous samples can be tested for positive hemadsorption, and the type can be determined using immunofluorescence. Type A and type B can also be distinguished by the number of proteins surrounding the RNA segments; for instance, type A has ten proteins, whereas type B has 11 proteins.

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