Influenza

n Begins abruptly n 20% to 50% of population affected n Complications can develop n Enter thru mucous membranes of eyes, nose or mouth n Contagious 3 to 4 days after symptoms appear

Symptoms n Headache n Chills n Dry cough n Body aches –myalgia n Malaise n Prostration

Complications n Accompany or follow the illness n Bacterial infections of lower respiratory tract –pneumonia n Symptoms of complication –fever, shaking chills –chest pain, coughing, sputum production

Influenza Viruses n 1930’s n A, B, C n Mutation –“older” antibody doesn’t recognize “newer” virus n Hemagglutinin (H) n Neuraminidase (N) n A(H1N1) and A(H3N2)

Influenza Viruses n Antigenic drift n Antigenic shift n Epidemic n Pandemic

Pandemics n –Spanish flu n –Asian flu n –Hong Kong flu

Vaccine (a.k.a. Flu Shot) n Made from inactivated (killed) influenza viruses n Give 6 to 8 weeks before flu season n Vaccine cannot cause flu n Side effects –soreness at site –fever, tiredness, sore muscles

Advantages of taking flu shot n Reduces the number of people hospitalized or die from pneumonia n Reduces the number of secondary URIs, missed work days, visits to Dr. n 70% to 90% effective in preventing flu in young adults

Antiviral Drugs n Amantadine n Rimantadine (Flumadine) n Relenza (Zanamivir for inhalation) n Tamaflu (Oseltamivir)