Improved methods of detection of meningococcal DNA from oropharyngeal swabs from cases and contacts of meningococcal disease

In the UK the increasing use of pre-admission parenteral antibiotic therapy in meningococcal disease has lessened the value of routine cultures as a t ool to confirm diagnosis, and laboratory confirmation of invasive meningoco ccal infection is achieved increasingly by non-culture, nucleic acid amplif ication methods. The purpose of this study was to evaluate a DNA extraction and meningococcal-specific DNA amplification methodology for detection of meningococci from oropharyngeal swabs. One hundred and six swabs from suspected or confirmed cases of meningococca l disease. and 94 swabs from contacts of meningococcal disease cases were e xamined. Of laboratory-confirmed cases, 38/65 (58.5%) yielded a positive or opharyngeal swab PCR result and 5/24 (20.8%) swabs from suspected but labor atory-unconfirmed cases were PCR positive. No significant differences in PC R positivity rates were found between the types of swab transport systems u tilized, but transport time to the testing laboratory was found to affect P CR positivity (P < 0.05). Application of meningococcus-specific PCR to oropharyngeal swabs, in additi on to routine culture of swabs, can provide valuable epidemiological inform ation as well as case confirmation for contact management. PCR amplificatio n of meningococcal PCR from oropharyngeal swabs will also increase the asce rtainment in swabbing surveys carried out as part of meningococcal disease outbreak investigation and management.