Pertussis

Introduction

Pertussis is a highly contagious bacterial respiratory tract infection common in children and adults. The incubation period is 7-21 days.

Complications of Pertussis

Complications of Pertussis include:

  • Subconjunctival haemorrhage
  • Otitis media
  • Apnoea
  • Pneumonia
  • Bronchiectasis
  • Activation of latent tuberculosis
  • Dehydration
  • Fever
  • Convulsions
  • Rectal prolapse, and
  • Malnutrition.

Patients should be admitted to hospital when complications are present.
Pertussis can be prevented by the “five-in-one” immunisation recommended for all children (See ‘Immunization’).
In the event of a child developing pertussis before immunisation, the “five in one” vaccine should still be given to protect against the four other diseases.
Pertussis during epidemics, or when there is a clear history of contact in a child with catarrh, appropriate antibiotics may help reduce the period of infectivity and transmission.
All cases should be reported to the District Disease Control Officer.

Cause of Pertussis

  • Pertussis is caused by Bordetella pertussis

Symptoms of Pertussis

Catarrhal Phase: Initial 1-2 weeks

  • Low grade fever
  • Nasal discharge
  • Mild cough

Paroxysmal phase: within the following 6-10 weeks

  • Episodes of violent repetitive cough ending with inspiratory whoop or vomiting (whoop may be absent in babies and adults)

Recovery (convalescent) phase: next 2-3 weeks

  • Gradual reduction in bouts of coughing

Signs of Pertussis

  • Apnoea (long pause in breathing) common in babies
  • Cyanosis

Investigations

  • FBC high total lymphocyte count
  • Chest X-ray (to exclude other causes of chronic cough)

Treatment for Pertussis

Objectives

The treatment objectives of pertussis are:

  1. To reduce transmission
  2. To prevent complications

Non-pharmacological treatment

  • Feed frequently between coughing spasms
  • Encourage adequate oral fluid intake

Pharmacological treatment

A. Patients and close contacts within 14 days of onset of symptoms

1st Line Treatment
Evidence Rating: [A]
Erythromycin, oral,
Adults: 500 mg 6 hourly for 7 days
Children:

  • 8-12 years; 250-500 mg 6 hourly for 7 days
  • 2-8 years; 250 mg of suspension 6 hourly for 7 days
  • 6 months-2 years; 125 mg of suspension 6 hourly for 7 days
  • < 6 months; not recommended (risk of pyloric stenosis). Consider Trimethoprim/ Sulphamethoxazole instead

Or

Evidence Rating: [B]
Azithromycin, oral,

  • Adults: 500 mg daily for 3 days
  • Children: 10 mg/kg body weight daily for 3 days

Children< 6 months: Not recommended because of a risk of pyloric stenosis). Consider Trimethoprim/ Sulphamethoxazole instead.

Or

Evidence Rating: [C]
Clarithromycin, oral,
Adults: 500 mg 12 hourly for 7 days
Children: 7.5 mg/kg 12 hourly for 7 days
2nd Line Treatment
Evidence Rating [C]
Trimethoprim/Sulphamethoxazole, oral,
Adults: 160/800 mg 12 hourly for 7 days
Children: 4/20 mg/kg 12 hourly for 7 days

B. Oxygen therapy when oxygen saturation <92%

Oxygen, intranasal or face mask, (if the patient has difficulty in breathing or is cyanosed)

Referral Criteria

Refer infants who have an episode of apnoea or cyanosis after initial resuscitation to a specialist.