About this disease

Whooping cough (or pertussis) is a highly contagious respiratory infection caused by the bacteria ‘bordetella pertussis‘. These bacteria attach to the cilia (tiny, hair-like extensions) that line part of the upper respiratory system. The bacteria release toxins (poisons), which damage the cilia and cause airways to swell.1

Although the infection is mild in adults, if passed on to vulnerable babies it can be life-threatening.

    1. Centres for Disease Control and Prevention (DCD) Pertussis Causes and Transmission (last updated September 8, 2015) Accessed 9th August 2017


Symptoms will start to appear from 1 to 3 weeks after exposure to the bacteria. The disease begins like a cold with a runny nose, mild fever and a cough. The cough gets worse and can last 1-2 months or longer.2 A thick, sticky mucus develops in the windpipe, which makes it difficult to eat, drink and breathe. In babies, this results in coughing fits often accompanied by a ‘whoop’ as it struggles to catch its breath. Older children and adults may just have a dry, persistent cough often without the ‘whoop’, so many cases are often mistaken for a bad chest cold or bronchitis. Although cases in adults are considered mild, they are still highly contagious and can easily be unknowingly passed on to others. Some children cough so much they vomit afterwards.

The coughing fits can go on for up to 10 weeks or more. The infection is generally milder in teens and adults, especially those who have been vaccinated.

Severe complications, which occur almost exclusively in unvaccinated people, include pneumonia (lung infection), hypoxic encephalopathy (lack of oxygen to the brain) and death.3


  • 2. Pertussis vaccines for Australians/NCIRS Fact sheet: March 2016.

    3. Australian Technical Advisory Group on Immunisation (ATAGI). The Australian immunisation Handbook 10th ed (2017 update). Canberra: Australian Government Department of Health, 2017.

How it is spread

Pertussis is a highly contagious and only found in humans. It is easily spread from person-to-person via droplets from close contact i.e. when you talk, sneeze, cough or kiss. Many babies who get pertussis are infected by older siblings, parents, or caregivers who might not even know they have the disease.1 People with pertussis are most infectious in the first three weeks after the onset of symptoms. If you catch it, there is an 80% chance that other members of your household will catch it too.

  • See above


Severe complications which occur almost exclusively in unvaccinated people, include pneumonia, hypoxic encephalopathy and death.

Some of complications of whooping cough in young babies:

• haemorrhage

• apnoea

• pneumonia

• inflammation of the brain

• convulsions

• permanent brain damage

• death4

  • 4. Better Health Channel Whooping Cough (last updated March 2016) accessed August 2017


Vaccination is the only form of prevention.  Children are eligible for Pertussis vaccination under the National Immunisation Program. See your GP to find out more.


Antibiotics may be given to prevent the spread of pertussis to other people. If the patient has been coughing for more than three weeks, they are no longer infectious. In these cases, antibiotics are usually not needed.

Info for Clinicians

Children under one year of age have a 50% hospitalisation rate 0.5% mortality.

Infants less than 6 months are at greatest risk of severe disease and death.

If a child under 6 months of age gets whooping cough, they will usually need to be admitted to hospital.5


  • Between 2008 and 2012, all Australian states experienced their largest pertussis epidemic. The highest rates of disease were in infants less than 6 months and children 5-9 years of age.2

    In 2018 there were 12,575 cases of pertussis reported nationally.6

    In 2018, children under 15 years of age accounted for 47% of the pertussis notifications.6

  • Outbreaks occur every 3-4 years but with reduced morbidity and mortality in vaccinated individuals.7

    A 3-dose primary series of immunisation with DTPa vaccine at 2, 4 and 6 months of age results in 84% protective efficacy against severe disease.8

    Immunity to pertussis wanes over time. Effectiveness of 3 doses of DTPa vaccine declined progressively from 2 years of age to less than 50% by 4 years of age.9

    A large trial in adolescents and adults demonstrated overall vaccine efficacy against confirmed pertussis of 92% within 2.5 years of vaccination.10

  • Compared to whole-cell pertussis vaccines (DTPw) which are no longer used in Australia, acellular pertussis vaccines are associated with a much lower incidence of:

    • Fever (20% vs 45%)
    • Local reactions (10% vs 40%)3

    Extensive limb swelling can occur with booster doses of DTPa. Such reactions commence within 48 hours of vaccination,

    • last 1-7 days and
    • resolve completely3

    In pregnant women, there is no increased risk of pregnancy outcomes such as stillbirth, pre-eclampsia, foetal distress, low birth weight or neonatal renal failure related to pertussis vaccination during pregnancy.3

  • Infants and children

    Free pertussis vaccine is available under the National Immunisation Program as follows2,11:

    Vaccine 2 mths[i] 4 mths 6 mths 18 mths 4 yrs 12-17 yrs
    (DTPa)[ii] 1st dose 2nd dose 3rd dose 1st booster 2nd booster        N/A
    (dTpa)[iii]       N/A       N/A       N/A       N/A       N/A 3rd booster

    [i] First dose can be given as early as 6 weeks of age

    [ii] DTPa = Diphtheria tetanus and acellular pertussis-containing vaccines, which are used in children < 10 years of age. There are six formulations: Infanrix (DTPa), Infanrix hexa (DTPa-hepB-IPV-Hib), Hexaxim (DTPa-hepB IPV-Hib), Infanrix IPV (DTPa-IPV), Quadracel (DTPa-IPV) and Tripacel (DTPa)

    [iii] dTpa signifies formulations that contain substantially lesser amounts of diphtheria toxoid and pertussis antigens than child (DTPa-containing) formulations. dTpa vaccines are used in adolescents and adults. There are four formulations: Boostrix (dTpa), Boostrix-IPV (dTpa-IPV), Adacel (dTpa) and Adacel Polio (dTpa-IPV)


    Older children and teenagers FREE catch up vaccines are now available for individuals 10 to 19 years of age.11

    Humanitarian entrants FREE catch up vaccines are now available through the NIP for refugees and other humanitarian entrants aged 20 years and over.11


    dTpa is recommended for any adult who wishes to reduce the likelihood of becoming ill with pertussis, but particularly important for special risk groups.3 Vaccination for adults is not funded under NIP, apart from pregnant women (see below).


    Special Risk Groups

    Pregnant women (now free on NIP)11 and people in contact with infants (not funded under NIP for these individuals).

  • 2. Pertussis vaccines for Australians/NCIRS Fact sheet: March 2016

    5. Royal Children’s Hospital (RCH) Kid’s info Whooping cough Fact Street accessed August 2017

    6. Department of Health, National Notifiable Diseases Surveillance system, Accessed 21 August 2019

    7. Quinn HE, McIntyre PB. Pertussis epidemiology in Australia over the decade 1995-2005 – trends by region and age group. Communicable Diseases Intelligence 2007;31:205-15

    8. Zhang L, Prietsch SO, Axelsson I, Halperin SA. Acellular vaccines for preventing whooping cough in children. Cochrane Database of Systematic Reviews 2012;(3):CD001478

    9. Quinn HE, Snelling TL, Macartney KK, McIntyre PB. Duration of protection after first dose of acellular pertussis vaccine in infants. Pediatrics 2014;133:e513-9

    10. Ward JI, Cherry JD, Chang SJ, et al. Efficacy of an acellular pertussis vaccine among adolescents and adults. New England Journal of Medicine 2005;353:1555-63

    11. Department of Health, National Immunisation Schedule Accessed 2nd September 2018


Page published:   8 March 2017

Page updated:      21 August 2019

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