1Diseas Classification
Diptheria
2Causative Agent
Corynebacterium diptheriae (+ phage toxin)
3Classification of CA
Gram-positive rod, aerobic, nonmotile, abundant fimbiae, produces diptheria exotoxin
4Epidemiology: Reservoir
Humans
5Epidemiology: POE
Respiratory Tract
6Epidemiology: MOT
Aerosol respiratory droplets, contact with contaminated body fluids
7Incubation Period
2-5 days
8Pathogenesis
Bacteria colonize upper respiratory tract and form a pseudomembrane that can obstruct the airway. They also secrete exotoxins that enter the bloodstream and inhibit protien synthesis in cells of the heart, kidneys, and nervous tissue resulting in paralysis and organ damage
9Symptoms
Adherent psuedomembrane, fever, bleeding, sore throat and difficulty swallowing, difficulty breathing, swollen lymph nodes, perceptible sweet smell, paralysis (first swallowing muscle), change to heart rhythem
10Diphtheria Toxin
Protien- 535 amino acid, A-B Toxin, Lethal Dose = 100ng/kg body weight
11A toxin attaches to
EF2 inhibitor
12B toxin binds to
receptor
13Complications
Blocking of the airway, damage to the heart muscle (myocarditis), nerve damage (polyneuropathy), kidney damage, paralysis, lung infection, current mortality rate 5-10% (up to 20% in individuals <5yrs and >40 yrs)
14Prevention
Vaccination- 1923 toxoid vaccine. created by heat and formaldehyde denaturation; current vaccines DTap, Tdap, DT, and Td
15Treatment
Antiserum (immunoglobulins)- Antitoxin therapy 1901, diphtheria antitoxin (DAT); Antibiotics- Penicillin, Erythromycine