Pertussis (whooping cough)

Question 1

True or false: pertussis is nationally notifiable?

Answer 1

True - routine.

Question 2

Which organism causes pertussis?

Answer 2

Bordatella pertussis

Produces various factors including toxin.

Question 3

How is pertussis transmitted?

Answer 3

Respiratory droplets
Contact with respiratory discharges
Fomite transmission rare

Possible airborne spread.

Question 4

What are the clinical features of pertussis?

Answer 4

Whooping cough

Initial catarrhal phase –> paroxysmal cough (post-tussive vomiting, whoop, apnoeas) can last 1-2 months

Complications: pneumonia / encephalitis

Severe disease in young infants. CFR < 0.5%. Partially vaccinated may have mild illness.

Question 5

Which groups are high-risk for pertussis?

Answer 5

< 6mo

Aim of PH response is to prevent disease in <6mo

Question 6

What are the case definitions for pertussis?

Answer 6

Confirmed
* Isolation/detection OR
* Serological + clinical

Probable: clinical + epi (one case in chain must be lab confirmed)

Question 7

How is pertussis diagnosed?

Answer 7

• PCR from NPA/NPS
• Culture (allows typing)
• Serology (Sn/Sp low)

Question 8

What is the incubation period for pertussis?

Answer 8

7-10 days (usual)

6-20 days (range)

Question 9

What is the infectious period for pertussis?

Answer 9

Onset of catarrhal symptoms.
Neglibile after 3 weeks.

Catarrhal symptoms = mild cough, fever, coryza

Question 10

When are pertussis cases considered non-infectious?

Answer 10

Whichever is earlier of:
* 21 days after cough onset OR
* 14 days after paroxysmal cough onset OR
* after 5 days of ABx

Question 11

What is the outbreak definition of pertussis?

Answer 11

≥2 cases with a plausible epi link (time and place).

Outbreak case definition may be cough lasting 14 days or more.

Question 12

How are outbreaks of pertussis managed?

Answer 12

General outbreak management principles: case, contact, environmental.

• Active case-finding
• Epi studies
• Alerts to clinicians/community
• Vaccination

Question 13

How is pertussis prevented?

Answer 13

Vaccination
* NIP - 2, 4, 6, 18mo and 4 years
* Booster dose adolescenets
* Sinlge dose dTpa each pregnancy (>20wks)
* HCWs/ECE every 10 years
* All adults >65 years if no dose in last 10
* Adult HH contacts/carers of infants

Question 14

What resources are available for public health management of pertussis?

Answer 14

SoNG, DoH protocol

Question 15

How are cases of pertussis managed?

Answer 15

• F/U children < 12mo (< 10yo best practice), pregnant women (last month preg), contact with < 6mo / pregnant, CC workers, HCW (maternity/neonatal)
• Treatment (clinician) - ABx
• Isolation / exclusion
  Primary school/ECEC until 21 days post cough onset or 5 days post ABx
  All others until no longer infectious
• Education - transmission, avoid contacts with infants/pregnant women

Question 16

How are contacts of pertussis managed?

Answer 16

• Treatment - ABx PPx within 14d of first contact for those who may transmit pertussis to high-risk groups
• Isolation / exclusion - unvaccinated contacts in primary school/ECEC/HCW generally excluded for 14d post exposure or 5d post Abx
• Monitor -
• Education - vica CC/IPC/Clinician - Sx, transmission, avoid high-risk settings

Question 17

Who are considered close contacts of pertussis cases?

Answer 17

• Family or HH contact
• Face-to-face ≥1 hr
• Overnight in same room

Question 18

Who are high-risk contacts of pertussis cases?

Answer 18

• Women in late pregnancy
• HH member if infant < 6mo present
• Staff/children in CC with infants < 6mo
• HCW - maternity / neonatal ward

Question 19

What environmental management is required for pertussis?

Answer 19

Not required.

Question 20

True or False: pertussis is one of the most commonly notified VPDs?

Answer 20

True

Question 21

How often to epidemics of pertussis occur in Australia?

Answer 21

Every 3-4 years

Question 22

What is one of the reasons for pertussis epidemics?

Answer 22

Waning immunity - significant reservoir of infection.