Gonococcus Reference Laboratory

The reference function is part of the Bacteria, Parasites & Fungi in the Infectious Disease Preparedness.

The genus Neisseria comprises about 20 species, two of which cause important diseases. 

• Neisseria gonorrhoeae (gonococci) causes gonorrhoea. The demonstration of gonococci in clinical specimens is always considered pathologic. 
• Neisseria meningitidis (meningococci) may cause invasive disease, in particular meningitis and septicaemia but asymptomatic (and unharmful) throat carriage is quite frequent. Occasionally, meningococci may cause other diseases, e.g. pneumonia, otitis media, conjunctivitis, or urethritis. The occurrence and characteristics of both species are monitored by the Neisseria and Streptococcus Reference Laboratory.
• Other Neisseria species are rarely pathogenic in humans and only under special circumstances. 
• All analytical methods in the Reference Laboratory are DANAK accredited according to the ISO/IEC 17025 standard. 

Purpose

• Surveillance of laboratory verified gonococci in Denmark. 
• Surveillance of antimicrobial resistance in gonococci. 
• If relevant, molecular typing of gonococci. 

Surveillance of gonococci in Denmark

The surveillance of gonorrhoea in Denmark is based on three reporting systems:

• In the mandatory laboratory reporting system all departments of clinical microbiology copy their results of laboratory testing for gonococci as well as certain data about the patient and the specimen into The Danish Microbiology Database (MiBa).
• In the mandatory clinical epidemiological reporting system the physician who treats the patient submits information to the Infectious Disease Epidemiology & Prevention about sexual orientation, country of infection, mode of infection etc.
• In the voluntary laboratory reporting system all departments of clinical microbiology submit gonococcus strains isolated from clinical specimens to the reference laboratory.

Surveillance of antimicrobial resistance in gonococci

All submitted isolates are tested for beta-lactamase production and susceptibility to azithromycin, ceftriaxon, and ciprofloxacin by determining MIC (minimum inhibitory concentration) using Etest. This antimicrobial panel may be expanded upon request to include e.g. gentamicin.

The panel is also expanded (with cefixime, and sometimes gentamicin, spectinomycin, tetracycline) when a subset of isolates (one isolate from each of 110 consecutive gonorrhoea cases) are examined for the annual participation in Euro-GASP (European Gonococcal Antimicrobial Surveillance Programme).

Characterisation of gonococci

Typing of the submitted gonococcus isolates is not routinely performed. If relevant, strains can be characterized by whole-genome sequencing including NG-MAST (Neisseria gonorrhoeae Multi Antigen Sequence Typing) and SNP-analysis (single nucleotid polymorphism).

Publication of the result of surveillance of gonococci

The surveillance data are published nationally and internationally. 

Nationally

A yearly report is published in EPI-NEWS and in DANMAP. 

Internationally 

Data on gonorrhoea are reported to EU’s database TESSy (The European Surveillance System) in ECDC. 

Data on a subset of the received gonococcal isolates are reported to Euro-GASP once annually.

Projects

EU project: The Reference Laboratory participates in laboratory projects in cooperation with Public Health England, London, and Department of Clinical Microbiology, University Hospital, Örebro, Sweden.

Participation in EQA (External Quality Assessment) programmes

The reference laboratory receives spiked specimens from UK-NEQAS and from Labquality in order to assess the quality of culture based diagnosis and susceptibility testing of gonococci. In addition, we cooperate with Public Health England, London, regarding quality assessment of the susceptibility testing of gonococci.