Oropharyngeal <i>Neisseria gonorrhoeae</i> in Women: Comparison of Routine Universal Testing and Selective Testing Using Dutch National Sexually Transmitted Infection Clinical Data

Abstract

Background: Women are not routinely tested for oropharyngeal Neisseria gonorrhoeae (N. gonorrhoeae). Currently, selective testing based on behaviour or risk groups is advocated by international guidelines. Many oropharyngeal infections remain undetected due to their asymptomatic nature, creating a reservoir for ongoing transmission. The optimal testing strategy for women is unknown as data on routine testing are lacking. Methods: Surveillance data obtained from all Dutch STI clinics between 2008 and 2017 were used (n=546,246 consultations). We compared the prevalence of oropharyngeal N. gonorrhoeae between routine universal testing (≥85% tested oropharyngeally per clinic-year) and selective testing (5-85%). Missed infections were calculated by extrapolating positivity found by routine universal testing to that of a weighted sample of all selectively tested women. Backward multivariable generalized estimating equations analyses were used to assess independent risk factors for oropharyngeal N. gonorrhoeae. Findings: Routine universal testing was used in 11% (57,359/501,642) of consultations and selective testing in 89% (444,283/501,642). Positivity was comparable at 1·4% (95% confidence interval 1·3-1·5, 703/50,962) and 1·4% (95% confidence interval 1·3-1·3, 1858/132,276, P=0·68), respectively. The proportions of oropharyngeal-only infections were 52% (368/703) and 47% (867/1,858), respectively. Selective testing would have missed 70·0% of oropharyngeal infections (95% confidence interval 69%-71%, 4,915/7,024). When using independent risk factors notified for STI (odds ratio 1·3, 95% confidence interval 1·03-1·5) and commercial sex work (odds ratio 4·1, 95% confidence interval 2·8-5·9) as testing indicators, 27·8% (5,418/19,455) of women would be tested identifying 55·6% (119/214) of oropharyngeal infections. Interpretation: Selective testing potentially misses two-thirds of oropharyngeal N. gonorrhoeae infections in women, of whom half will have oropharyngeal-only infections. Using independent risk factors to guide testing is a minimal testing strategy. Routine universal testing is the preferred scenario to detect the vast majority of infections. However, future studies are needed to evaluate the cost-effectiveness and impact on antimicrobial resistance. Funding Statement: This work was supported by the Public Health Service South Limburg, the Netherlands. Declaration of Interests: The authors declare no conflicts of interest. Ethics Approval Statement: Because the retrospective coded data originated from standard care and were analysed anonymously, neither a full ethical review nor informed consent for data analysis was needed, as confirmed and approved by the Medical Ethical Committee of Maastricht University (METC 2017-0251).