Bordetella pertussis (whooping cough)

Question 1

shape and gram stain

Answer 1

gram (-), encapsulated

Question 2

reservoir

Answer 2

human asymptomatic carriers

Question 3

transmission

Answer 3

contact with respiratory droplets

Question 4

caused by which toxin

Answer 4

pertussis toxin

Question 5

pertussis toxin function

Answer 5

A subunit inactivates inhibatory regulaotry G protein , causing increase in cAMP production

Question 6

increase in cAMP production causes

Answer 6

increased mucus, decreased killing ability of phagocytes

Question 7

pathogenesis

Answer 7

cells are inhaled, attached to ciliated cells of respiratory epithelium

Question 8

tracheal cytotoxin

Answer 8

toxic to ciliated epithelial cells –> disrupts mucocilliary clearance

Question 9

incubation stage

Answer 9

• duration: 7-10 days
• symptoms: none

Question 10

catarrhal stage

Answer 10

• duration: 1-2 weeks
• symptoms: rhonorrhea, malaise, fever, sneezing, anorexia

Question 11

paroxysmal stage

Answer 11

• duration: 2-4 weeks
• symptoms: repetitive cough with whoops, vomiting, leukocytosis

Question 12

convalescent stage

Answer 12

• duration: 3-4 weeks (or longer)
• symptoms: diminished paroxysmal cough, development of secondary complication (pneumonia, seizures, encephalophathy)

Question 13

treatment

Answer 13

primarily supportive
antibiotics effective if treated early

Question 14

prevention

Answer 14

• immunization with DTaP starting at 2 months
• subunits of B. pertussis are used in the vaccine
• requires boosters, Tdap

Question 15

killed whole-cell vaccine, DPT

Answer 15

• fever, agitiation, febrile seizures
• long term immunity

Question 16

acellular vaccines, DTaP

Answer 16

• fewer, milder side effects
• waning immunity

Question 17

vaccinating pregnant patients

Answer 17

• pregnant women should receive a dose of the Tdap vaccine during each pregnancy, preferably during the early part of gestational weeks 27 through 36