What is Whooping cough?
Pertussis is an extremely contagious infection of the respiratory tract caused by the bacterium Bordetella pertussis. Its more common name, ‘whooping cough’, is owed to the sound made during the intake of large gasping breaths following a bout of uncontrollable coughing. This high-pitched whoop may be absent in very young infants, older children and adults.
What are the symptoms?
Symptoms typically appear 7 – 10 days following infection and at first resemble those of a cold: blocked or runny nose, tiredness, a cough and mild fever. Typically the cough will gradually worsen and severe bouts of uncontrollable coughing can develop, at times triggering vomiting and choking. Its awful symptoms are often worse at night. If not treated early, people with whooping cough are infectious for a period of 3 weeks.
Complications can be life-threatening, particularly in newborns and premature infants, when the infection can cause apnoea (temporary cessation of breathing), pneumonia, low blood pressure leading to organ failure, seizures, brain damage and, in some cases, death. Hospitalisation rates are high among babies under 12 months of age infected with pertussis.
Disease outcomes in older children and adults are not as severe, however among adults, asthmatics and smokers have a higher risk of developing pneumonia. Coughing bouts can lead to associated complications such as fainting, dizziness, incontinence, rib fractures and broken blood vessels in the white of eyes.
The period of infectiousness can extend for three weeks after the onset of the cough and the infection itself can linger for one to two months.
Where is it found?
Pertussis is found in all regions of the world and, despite established immunisation programs over the past 50 years, it remains a challenging disease to control. One major stumbling block is the waning of immunity gained from immunisation or infection over time, leading to renewed susceptibility to infection. Parents are the most likely source of infection for infants and the highest rates of disease occur in infants under 6 months and children aged between 5 and 9 years.
Outbreaks are cyclical, generally happening every 3 to 4 years. The largest outbreak of whooping cough since reporting began in 1991 occurred between 2008 and 2012 in all states and territories of Australia.
Risk to travellers
Travellers who last had a tetanus dose more than 10 years ago (5 years for high-risk itineraries such as hiking etc.) are recommended to receive a booster dose of a tetanus-containing vaccine before departure - this can be combined with pertussis toxoid if 10 years or more has lapsed since the last dose was given.
How is Whooping cough transmitted?
Whooping cough is spread when an infected individual coughs or sneezes bacteria into the air and it is inhaled by others nearby.
How is Whooping cough treated?
Diagnosis is preferably made through PCR testing of nose / throat swabs and early treatment, which is best started before coughing develops and also to prevent onward transmission, is with the appropriate antibiotics.
What is Whooping cough Vaccination?
In Australia, whooping cough vaccines for adults are only available in combination with diphtheria and tetanus, with or without another antigen, the inactivated poliomyelitis vaccine (IPV).
Vaccination is recommended for any adult who wishes to reduce their likelihood of becoming infected, and is particularly recommended for those in close contact with young infants (e.g. family members, healthcare workers, child care workers). Vaccination is also recommended for women between 20 and 32 weeks in each pregnancy and is funded under the National Immunisation Program (NIP).
Adults: Pertussis toxoid given in combination with Tetanus/Diphtheria (Adacel / Boostrix) or Tetanus/ Diphtheria/ Polio (Adacel Polio / Boostrix IPV).
Children under 10 years: Pertussis toxoid given in combination with Tetanus/Diphtheria and others. (InfanrixHexa, Infanrix IPV, Hexaxim, Quadracel, Tripacel)
Whooping cough vaccines provide good protection from infection but the fading of immunity over time means that boosters are needed.
A primary series of vaccinations is given to infants from 6-8 weeks of age. Three doses are administered at least 4 weeks apart, with boosters at 18 months, 4 years of age and again at 11-17 years of age (depending on state/territory schedule).
A single booster of tetanus/diphtheria-containing vaccine (preferably also containing pertussis) is given at 50 years of age, however boosters are administered every 10 years for travellers to countries where health services are difficult to access. This timeframe is reduced to every 5 years for those travellers who will be undertaking activities with a high risk of injury, i.e. mountaineering, bike riding, rock climbing and caving in areas remote from good medical care.
Level of protection
Possible Side Effects
Pain, redness or swelling at injection site, as well as transient fever, headache and malaise.
In young babies, decreased appetite, fever and crying. In children who had DTP (tetanus, diphtheria, whooping cough) as their primary vaccination, boosting with the same vaccine produced extensive limb swelling in 2% of recipients.
Acute allergic reactions occur in 1 per 1 million doses.