IMM250H1 Lecture Notes - Lecture 9: Upper Respiratory Tract Infection, Orthomyxoviridae, Hpv Vaccines
Document Summary
Lecture 9 - emerging influenza variants and the case for improved vaccines. Flu is an acute upper respiratory infection. Fever, cough and systemic symptoms such as muscle aches. Symptoms can range from mild to severe. Flu more severe in very old, very young, those with chronic conditions leading to hospitalizations, secondary infections, death. Three kinds of influenza virus: influenza a - regular outbreaks and occasional pandemics. Different subtypes (e. g. h1n1", h3n2") and different strains within subtypes: influenza b - regular outbreaks. Different lineages" (e. g. b/yamagata, b/victoria) and different strains within lineages: influenza c - common but seldom causes disease. Host of origin (note: human doesn"t have a designation!) Viral ha attach to the host sialic acid (carbohydrates) Endocytosis 0 ha changes conformation fuse with endosome release content into cytosol. Positive transit also acts as template for more negative strands. Ha precursor cleavage can only occur in lung epithelial (allow virus to escape)
