Diagnostic tests are recommended when there is enough evidence to indicate that pertussis may be existent. There are three major diagnostic tests for pertussis: culture, polymerase chain reaction (PCR), and serology. The gold standard is the culture because it is the only 100% - specific method which can identify the strains of B. pertussis responsible for an illness.5 It is a swab taken of the throat and/or nose to be checked at a laboratory. Furthermore, the samples have to be collected during the first 2 weeks of cough because the viable bacteria are still existing in the nasopharynx; however, it demands about seven days to gain the results back. PCR is a faster test that does not require an alive bacterium, yet it can convey false results.5 The specimens should be taken at 0 to 4 weeks after the cough onset. After the fourth week, the risk of obtaining falsely-negative results will increase due to the decreases in the amount of bacterial DNA in the nasopharynx. Finally, the serology test is the most advantageous test to diagnose pertussis in the later stage in week 12; the appropriate timing for specimen collecting is in weeks 2 to 8 when the antibodies reach the highest point.5
Diagnostic tests are recommended when there is enough evidence to indicate that pertussis may be existent. There are three major diagnostic tests for pertussis: culture, polymerase chain reaction (PCR), and serology. The gold standard is the culture because it is the only 100% - specific method which can identify the strains of B. pertussis responsible for an illness.5 It is a swab taken of the throat and/or nose to be checked at a laboratory. Furthermore, the samples have to be collected during the first 2 weeks of cough because the viable bacteria are still existing in the nasopharynx; however, it demands about seven days to gain the results back. PCR is a faster test that does not require an alive bacterium, yet it can convey false results.5 The specimens should be taken at 0 to 4 weeks after the cough onset. After the fourth week, the risk of obtaining falsely-negative results will increase due to the decreases in the amount of bacterial DNA in the nasopharynx. Finally, the serology test is the most advantageous test to diagnose pertussis in the later stage in week 12; the appropriate timing for specimen collecting is in weeks 2 to 8 when the antibodies reach the highest point.5