Pertussis Pseudo-outbreak Linked to Specimens Contaminated by Bordetella pertussis DNA From Clinic Surfaces
- 1 February 2012
- journal article
- Published by American Academy of Pediatrics (AAP) in PEDIATRICS
- Vol. 129 (2), e424-e430
- https://doi.org/10.1542/peds.2011-1710
Abstract
BACKGROUND AND OBJECTIVES: We investigated a pertussis outbreak characterized by atypical cases, confirmed by polymerase chain reaction (PCR) alone at a single laboratory, which persisted despite high vaccine coverage and routine control measures. We aimed to determine whether Bordetella pertussis was the causative agent and advise on control interventions. METHODS: We conducted case ascertainment, confirmatory testing for pertussis and other pathogens, and an assessment for possible sources of specimen contamination, including a survey of clinic practices, sampling clinics for B pertussis DNA, and review of laboratory quality indicators. RESULTS: Between November 28, 2008, and September 4, 2009, 125 cases were reported, of which 92 (74%) were PCR positive. Cases occurring after April 2009 (n = 79; 63%) had fewer classic pertussis symptoms (63% vs 98%; P < .01), smaller amounts of B pertussis DNA (mean PCR cycle threshold value: 40.9 vs 33.1; P < .01), and a greater proportion of PCR-positive results (34% vs 6%; P < .01). Cultures and serology for B pertussis were negative. Other common respiratory pathogens were detected. We identified factors that likely resulted in specimen contamination at the point of collection: environmentally present B pertussis DNA in clinics from vaccine, clinic standard specimen collection practices, use of liquid transport medium, and lack of clinically relevant PCR cutoffs. CONCLUSIONS: A summer pertussis pseudo-outbreak, multifactorial in cause, likely occurred. Recommendations beyond standard practice were made to providers on specimen collection and environmental cleaning, and to laboratories on standardizing PCR protocols and reporting results, to minimize false-positive results from contaminated clinical specimens.Keywords
This publication has 13 references indexed in Scilit:
- Development and Analytical Validation of an Immunoassay for Quantifying Serum Anti-Pertussis Toxin Antibodies Resulting from Bordetella pertussis InfectionClinical and Vaccine Immunology, 2009
- Development and evaluation of dual-target real-time polymerase chain reaction assays to detect Bordetella spp.Diagnostic Microbiology and Infectious Disease, 2008
- Real-Time Polymerase Chain Reaction Detection of Bordetella pertussis DNA in Acellular Pertussis VaccinesThe Pediatric Infectious Disease Journal, 2008
- Outbreaks of Respiratory Illness Mistakenly Attributed to Pertussis—New Hampshire, Massachusetts, and Tennessee, 2004-2006JAMA, 2007
- Evaluation of Polymerase Chain Reaction and Culture for Diagnosis of Pertussis in the Control of a County-Wide Outbreak Focused among Adolescents and AdultsClinical Infectious Diseases, 2007
- Establishment of Diagnostic Cutoff Points for Levels of Serum Antibodies to Pertussis Toxin, Filamentous Hemagglutinin, and Fimbriae in Adolescents and Adults in the United StatesClinical and Vaccine Immunology, 2004
- Comparison of culture and PCR for detection of Bordetella pertussis and Bordetella parapertussis under routine laboratory conditionsJournal of Medical Microbiology, 2004
- Laboratory diagnosis of pertussis infections: the role of PCR and serologyJournal of Medical Microbiology, 2004
- Issues Associated with and Recommendations for Using PCR To Detect Outbreaks of PertussisJournal of Clinical Microbiology, 2002
- Microbiological and Serological Diagnosis of PertussisClinical Infectious Diseases, 1999