Comparison of Bacterial Loads in Oropharyngeal and Nasopharyngeal Swabs for PCR-Based Detection of Pertussis: Findings from a Multicenter Prospective Study

Category	Detail
Condition	Pertussis
Key Mechanisms	Respiratory infection caused by Bordetella pertussis
Target Population	Patients presenting with cough; PCR positivity was highest among adolescents
Care Setting	Outpatient clinics and emergency departments at five institutions in Fukuoka Prefecture, Japan

Real-time PCR was used to detect B pertussis in nasopharyngeal and oropharyngeal swabs.
Oropharyngeal swabs are less invasive and easier to collect than nasopharyngeal swabs.
Of 475 patients, 113 (23.8%) were PCR-positive for B pertussis.
Pertussis vaccination was reported in 95.4% of participants; PCR positivity did not differ significantly by vaccination status.
Median age was 13.0 years, and PCR positivity was highest among adolescents, particularly those aged 13 to 15 years.

The study did not issue clinical guidelines; the points below reflect its methods, findings, and conclusions.

Consider oropharyngeal swabs as a practical alternative for PCR-based pertussis detection.
Consider PCR early after symptom onset and serology during later stages.

The study did not evaluate treatment responses or establish management recommendations.

Diagnostic strategies should account for specimen type, patient age, and time from symptom onset.

Waning vaccine-induced immunity may contribute to the increased detection of pertussis among adolescents.
The macrolide resistance-associated A2047G mutation was detected in 65 of 73 analyzed PCR-positive cases (89.0%), supporting continued surveillance.

The study enrolled 475 patients with cough presenting to outpatient clinics or emergency departments.

Macrolide resistance-associated mutations were evaluated, but clinical outcomes and treatment responses were not assessed.

Use trained health care professionals and standardized procedures to collect specimens.
Consider the interval between symptom onset and specimen collection when selecting diagnostic tests.
Interpret PCR and serology as complementary tests with different temporal patterns.

Oropharyngeal Swabs Show Higher Bacterial Loads Than Nasopharyngeal Swabs for PCR Detection of Pertussis: A Multicenter Prospective Study
Supplementary materials accompanying the study
National guideline for pathogen detection of pertussis, fourth edition, revised March 2024
Novel Multitarget Real-Time PCR Assay for Rapid Detection of Bordetella Species in Clinical Specimens
Waning Protection After Acellular Pertussis Vaccination

Clinical Scorecard: Comparison of Bacterial Loads in Oropharyngeal and Nasopharyngeal Swabs for PCR-Based Detection of Pertussis: Findings from a Multicenter Prospective Study