Whooping cough

Pertussis (infection by Bordetella pertussis), commonly known as whooping cough, is a respiratory tract infection characterised by its severe hacking cough which is often followed by a high-pitched intake of breath that sounds like a ‘whoop’ (UK Health Security Agency, 2016). It is a highly infectious disease, with approximately 150 000 cases reported globally in 2018 (World Health Organization, 2018). It is still high on the list of controlled infectious diseases, despite worldwide mass vaccinations (Medkova et al, 2023). In recent decades, there has been a significant increase in the incidence of whooping cough, particularly the atypical forms, among adolescents and adults, and it is re-emerging in many regions of the globe (Alqarni et al, 2022).

The disease usually begins with an initial catarrhal stage, followed by an irritating cough within 2–3 weeks that gradually becomes paroxysmal (UK Health Security Agency, 2016). The paroxysms can be followed by a distinctive whoop sound and vomiting. Younger children may not have a whoop, but can experience coughing spasms that may be followed by periods of apnoea. Patients may have whooping cough for 2–3 months. Adults can present with a non-productive cough without fever (Public Health England (PHE), 2018).

Minor complications of whooping cough can include:

• subconjunctival haemorrhages
• epistaxis (nosebleeds)
• facial oedema
• ulceration of the tongue or surrounding area
• suppurative otitis media (chronic middle ear infection)

Pertussis may be complicated by bronchopneumonia, weight loss as a result of the vomiting, and cerebral hypoxia with a resulting risk of brain damage. Pertussis can also cause congenital nephrotic syndrome, which can develop in the first 3 months of life (Kouli et al, 2020). Congenital nephrotic syndrome usually comprises:

• proteinuria
• hypoalbuminemia
• hyperlipidaemia
• oedema

Pertussis causes high mortality among infants aged under 1 year old, although it can affect people of any age (Jamal et al, 2022). Severe complications and death occur most commonly in infants under 6 months of age.

Whooping cough is caused by B. pertussis, which is only found in humans. The bacteria attach to the cilia that line the respiratory system. Medkova et al (2023) observed large numbers of persistent B. pertussis in the upper respiratory tract of 25% of patients with whooping cough during their convalescence period, facilitating spread of the disease.

Whooping cough may be suspected in any person with an acute cough lasting for 14 days or more without an apparent cause, in addition to one or more of the following:

Whooping cough is a nationally notifiable disease and clinicians need to report suspected cases to their local public health agency. Confirmation of clinically suspected cases should be supported by positive laboratory test (UK Health Security Agency, 2023b) – by culture and isolation of B. pertussis, and detection of its DNA (from nasopharyngeal swabs, perinasal swabs, nasopharyngeal aspirates or throat swabs) (PHE, 2018). Serum or oral fluid can be tested for antibodies, but usually only provides a late or retrospective diagnosis (PHE, 2018). Children aged 2–17 years old can have pertussis antibodies assessed under the Oral Fluid Enhanced Surveillance scheme (UK Health Security Agency, 2023b). This is recommended when the cough has continued for more than 14 days and the patient has not already been tested for laboratory evidence of whooping cough (UK Health Security Agency, 2023b).

Whooping cough can be confirmed when any person with signs and symptoms also presents with:

• B. pertussis isolated from a respiratory sample
• Anti-pertussis toxin IgG titre >70 IU/ml from a serum or >70 aU from an oral fluid specimen (in the absence of vaccination within the past year)
• B. pertussis polymerase chain reaction (PCR) positive in a respiratory clinical specimen (PHE, 2018)

The best way to prevent whooping cough is to be vaccinated. The current vaccine is given as part of the primary immunisations in the UK that start at 8 weeks of age. It is then repeated as part of the preschool booster (UK Health Security Agency, 2016). Although vaccines protect against severe disease, the vaccine-induced protection wanes over time, so it is important to encourage vaccine uptake across the primary and booster course. The vaccine coverage estimates for primary immunisation in England were 91.5% and 85.4% for the booster dose by 5 years of age, slightly lower than the coverage estimates for October–December 2019 (PHE, 2022).

In the UK, vaccination is recommended between 16 and 32 weeks of gestation to provide protection to young infants (Calvert et al, 2023). The maternal vaccination programme is effective in protecting the newborn until they have their first vaccinations at 8 weeks old (UK Health Security Agency, 2016). To reduce cases of whooping cough and protect the age groups that are considered at risk for the disease, it is important to maintain a high level of vaccination coverage (Stefanelli, 2019).

There is no clear evidence for an effective treatment for the cough in whooping cough (Bettiol et al, 2012; Wang et al, 2014). However, macrolides, such as azithromycin and clarithromycin, are the preferred choice for prophylaxis and treatment of pertussis (PHE, 2018). Clarithromycin is the first-line choice of antibiotic for use in neonates. Postexposure antimicrobial prophylaxis is also recommended for household contacts of whooping cough cases within 21 days of exposure (UK Health Security Agency, 2016; PHE, 2018). The cough can be challenging especially for parents of young children who witness severe bouts of coughing. The healthcare professional must assure them that the baby or child's airway will not be obstructed. Much of the management of whooping cough is about education, prevention of the disease and its ongoing symptoms.

Nursing and Midwifery Council: standards of proficiency for registered nurses

Part 2: Procedures for the planning, provision and management of person-centred nursing care

9. Use evidence-based, best practice approaches for meeting needs for care and support with the prevention and management of infection, accurately assessing the person’s capacity for independence and self-care and initiating appropriate interventions

9.1 observe, assess and respond rapidly to potential infection risks using best practice guidelines

9.2 use standard precautions protocols

European Centre for Disease Prevention and Control: https://www.ecdc.europa.eu/en/pertussis-whooping-cough 

NHS: https://www.nhs.uk/conditions/whooping-cough/ 

Travel Health Pro: https://travelhealthpro.org.uk/factsheet/16/pertussis-whooping-cough-and-travel 

World Health Organization: https://www.who.int/health-topics/pertussis#tab=tab_1 

References

Alqarni MM, Nasir A, Alyami MA et al. A SEIR epidemic model of whooping cough-like infections and its dynamically consistent approximation. Complexity. 2022. https://doi.org/10.1155/2022/3642444 

Bettiol S, Wang K, Thompson MJ et al. Symptomatic treatment of the cough in whooping cough. Cochrane Database Syst Rev. 2012;(5):CD003257. https://doi.org/10.1002/14651858.CD003257.pub4 

Calvert A, Amirthalingam G, Andrews N et al. Optimising the timing of whooping cough immunisation in mums (OpTIMUM) through investigating pertussis vaccination in pregnancy: an open-label, equivalence, randomised controlled trial. Lancet Microbe. 2023;4(5):e300-e308. https://doi.org/10.1016/S2666-5247(22)00332-9 

Hewitt M, Canning BJ. Coughing precipitated by Bordetella pertussis infection. Lung. 2010;188 Suppl 1:S73-S79. https://doi.org/10.1007/s00408-009-9196-9 

Hodder SL, Mortimer EA Jr. Epidemiology of pertussis and reactions to pertussis vaccine. Epidemiol Rev. 1992;14:243-267. https://doi.org/10.1093/oxfordjournals.epirev.a036089 

Jamal A, Jahan S, Choudhry H, Rather IA, Khan MI. A Subtraction genomics-based approach to identify and characterize new drug targets in bordetella pertussis: whooping cough. Vaccines (Basel). 2022;10(11):1915. https://doi.org/10.3390/vaccines10111915 

Kouli A, Trab SS, Alshaghel S, Mouti MB, Hamdoun H. Congenital nephrotic syndrome as a complication of whooping cough: a case report. Oxf Med Case Reports. 2020;2020(2):omaa007. https://doi.org/10.1093/omcr/omaa007 

Medkova AY, Semin EG, Kulikov SV et al. Composition of populations and durations of persistence of bordetella pertussis bacteria in patients with whooping cough and contact persons. Molecular Genetics, Microbiology and Virology. 2023;38(2), 61-69. https://doi.org/10.3103/S0891416823020064 

Public Health England (PHE). Guidelines for the public health management of pertussis in England. 2018. https://assets.publishing.service.gov.uk/media/5c0a856aed915d0c1bc0d51e/Guidelines_for_the_Public_Health_management_of_Pertussis_in_England.pdf (accessed 22 November 2023)

Public Health England. Pertussis: annual data tables and graphs for 2021. 2022. https://www.gov.uk/government/publications/whooping-cough-pertussis-statistics (accessed 29 November 2023)

Stefanelli P. Pertussis: Identification, prevention and control. Adv Exp Med Biol. 2019;1183:127-136. https://doi.org/10.1007/5584_2019_408 

UK Health Security Agency. Pertussis. 2016. https://assets.publishing.service.gov.uk/media/5a7487abed915d0e8bf19080/Pertussis_Green_Book_Chapter_24_Ap2016.pdf (accessed 22 November 2023)

UK Health Security Agency. Pertussis: guidance, data and analysis. 2023a. https://www.gov.uk/government/collections/pertussis-guidance-data-and-analysis (accessed 22 November 2023)

UK Health Security Agency (UKHSA). Information for pertussis (whooping cough) oral fluid testing. 2023b. https://www.gov.uk/government/publications/pertussis-whooping-cough-oral-fluid-laboratory-request-form-and-instructions (accessed 22 November 2023)

Wang K, Bettiol S, Thompson MJ, et al. Symptomatic treatment of the cough in whooping cough. Cochrane Database Syst Rev. 2014;2014(9):CD003257. https://doi.org/10.1002/14651858.CD003257.pub5 

World Health Organization. Pertussis. 2018. https://www.who.int/health-topics/pertussis#tab=tab_1 (accessed 22 November 2023)