Infectious Disease Quiz 1

Streptococcus pneumonia

Thick polysaccharide capsule

Encapsulated pneumococci inhaled into alveoli and multiply rapidly, cause inflammatory response and pleurisy

Penicillin, erythromycin, vaccine available

Grossly bloody sputum

Klebsiella pneumonia

Cephalosporin with an aminoglycoside

Capsule and adhesins

Klebsiella

Incubation period is less than two days, headache, fever, sore throat, muscle pain, dry cough. Acute symptoms last a week.

Inhalation of influenza a in orthonyxovirus family. Virion attaches enters cells via endocytosis, HA attaches to receptors on host epithelial cells, NA destroys surface receptors that bind to budding virion ma

Hemagglutin antigen and nueraminidase antigen are glycoproteins spikes embedded in envelope of flu virus

Caused by antigenic drift which are minor mutation in HA and NA genes, often a signal amino acid

Caused by antigenic shift. This is uncommon but a concurrent infection allows a mixture of eight rna segments. The human strains gain novel HA OR NA antigens

Infectious for humans who have no herd immunity Causes severe disease Spreads easily from person to person

Antivirals and vaccines Multitalented vaccines are against the three most important strains in circulation. 80-90% effective but new one is required each year because of drift

Diptheroids (oily regions) Staphylococci (salt tolerant) Malassezia (tiny lipid dependent yeasts)

Use substances in sweat as nutrients and their by products inhibit other microbes

Opportunistic pathogens Body odor

Hair follicle infections (boils, carbuncles) Staphylococcal scalded skin syndrome

Chicken pox and shingles

Measles

S aureus strain produce a toxin, exofoliatin, that is carried by bloodstream and attacks large areas by causing outer layer of skin to peel off Symptoms: within 48 hrs of redness skin becomes wrinkled and fluid filled blisters develop

Mutiplication of virus in upper respiratory tract followed by dissemination via bloodstream to the skin, giant cell formation, itchy bumps and blisters in various stages, fever