At a glance
Also known as
Pertussis; Whooping cough
Why get tested?
To detect and diagnose Bordetella pertussis, the bacteria causing whooping cough infection.
When to get tested?
When you have persistent, sharp spasms or fits of coughing (paroxysms) that the doctor suspects is due to pertussis (whooping cough) or when you have symptoms of a cold and have been exposed to someone with pertussis
A nasopharyngeal (NP) swab, a nasal aspirate or occasionally, a small blood sample drawn from a vein in your arm
Test preparation needed?
What is being tested?
This is a group of tests that are performed to detect and diagnose a Bordetella pertussis infection. B. pertussis is a that targets the lungs, typically causing a three-stage respiratory infection that is known as pertussis or more commonly whooping cough. It is highly contagious and causes a prolonged infection that is passed from person to person through respiratory droplets such as during sneezing or coughing and close contact. Most cases of pertussis in Australia occur between August and February each year, infecting mostly children under 2 years of age.
The for pertussis varies from a few days to up to a couple of weeks. The first stage of the disease, called the catarrhal stage, usually lasts about two weeks and symptoms may resemble a mild cold. It is followed by the convulsive or paroxysmal stage, which may last for one or two weeks or persist for a couple of months and is characterised by severe bouts of coughing with possible vomiting. Night attacks also can occur. Eventually, the frequency of the coughing starts to decrease and the infected person enters the convalescent stage, with coughing decreasing over the next several weeks. Pertussis infection, however, can sometimes lead to complications such as pneumonia, encephalitis, and seizures and can be deadly. Infants tend to be the most severely affected and may require hospitalisation.
Pertussis infections used to be very common in Australia affecting a peak of 49,500 people in 1930 (800 cases per 100,000 population). Improved living conditions and the introduction of mass vaccination with the pertussis in 1953, had decreased this number to less than 5,000 in 2007 (3 cases per 100,000). However, neither the vaccine nor previous whooping cough infection confers lifetime immunity and there are still periodic outbreaks of pertussis in young unvaccinated infants, in adolescents and in adults. Adults and adolescents are now seen as reservoirs of transmission to young children. Improved diagnostic tests for pertussis have also contributed to the greater number of cases reported. In 2014, 11,866 cases of pertussis were notified nationally to public health units (70 cases per 100,000).
Pertussis testing is used to diagnose these infections and to help minimise their spread to others. Several different types of tests are available to detect pertussis infection. Some of these include:
- - detection of B. Pertussis genetic material
- Direct fluorescent antibody (DFA)
- Blood tests for pertussis (serology) - , ,
Pertussis can be challenging to diagnose at times because the symptoms that present during the catarrhal stage are frequently indistinguishable from those of a common cold or of another respiratory illness such as bronchitis, influenza, and, in children, Respiratory Syncytial Virus (RSV). In the paroxysmal stage, many adults and vaccinated patients who have pertussis will present with only persistent coughing. Suspicion of pertussis infection is increased in patients who have the classic “whoop,” in people who have cold symptoms and have been in close contact with someone who has been diagnosed with pertussis and when there is a known pertussis outbreak in the community. A pertussis PCR test will usually be ordered on these patients but should not be performed on close contacts that do not have any symptoms.
How is the sample collected for testing?
Sample collection technique is critical in pertussis testing. For testing by PCR and culture, a nasopharyngeal (NP) swab or nasal aspirate is used. The nasopharyngeal swab is collected by having you tip your head back and then a swab is gently inserted into one of your nostrils until resistance is met. It is left in place for several seconds, then rotated several times to collect cells, and withdrawn. This is not painful, but it may tickle a bit, cause your eyes to tear and likely to provoke a coughing paroxysm. For a nasal aspirate, a syringe is used to push a small amount of sterile saline into your nose, and then gentle suction is applied to collect the resulting fluid. For antibody testing, a blood sample is obtained by inserting a needle into a vein in the arm.
Is any test preparation needed to ensure the quality of the sample?
No test preparation is needed.