Pertussis/whooping cough
Questionnaire/history:
Acute cough for ≥ 14 days without apparent cause + > 1 of
Paroxysms of coughing
Post-tussive vomiting
Inspiratory whoop
Apnoea with or without cyanosis for infants < 1 year
Immune status?
(Note: Caused by bacteria Bordetella pertussis, symptoms lasting for 2-6 weeks and in some cases months, incubation period usually 7-10 days (range 5-21))
Complication?
Apnoea, pneumonia, seizures, encephalopathy, otitis media, unilateral hearing loss, and then those due to increased intra-thoracic/abdominal pressure, eg pneumothorax, hernias, rib fracture, incontinence?
Investigations:
< 2 years:
< 21 days post cough onset (PCR testing (nasopharyngeal sample) + culture from nasopharynx if local facilities permit)
Late presentation (>14 days post cough onset): serology (not advised if < 12 months or vaccinated within last year) as sensitivity of PCR falls after 2 weeks
> 2years:
< 21 days post cough onset (PCR testing (nasopharyngeal sample) + culture from nasopharynx if local facilities permit)
Late presentation (>14 days post cough onset):
2-17 years: oral fluid testing or serology
>17 years: serology
In some areas, clinical diagnosis may be enough
Management:
Admit if:
Aged < 6 months and acutely unwell
Significant breathing difficulties eg apnoea episodes, severe paroxysms, cyanosis
Antibiotics:
Start as soon as possible after the onset of illness and certainly within 3 weeks
The main benefit is to eradicate the bacteria and prevent transmission
If symptoms have lasted for > 3 weeks, there is little benefit in giving antibiotics
If aged < 1 month use clarithromycin (but ?consider admission in this age group)
If aged > 1 month and not pregnant use either clarithromycin or azithromycin
If pregnant use erythromycin
Advised exclusion from school/place of work for 2 days after starting antibiotics or for 21 days after onset of symptoms if not treated with antibiotics
Clinically suspected or confirmed cases should be notified to Public Health
Prophylaxis for vulnerable contacts:
Recommended when the onset of illness was in the preceding 21days
This should be managed with assistance from the public health team
Resource(s):
PHE 2018