An updated molecular diagnostic for surveillance of tetM in Neisseria gonorrhoeae.

Doxycycline post-exposure prophylaxis (doxy-PEP) for sexually transmitted bacterial infections reduces the risk of syphilis and chlamydia, but effectiveness against gonorrhea is variable, likely attributable to varying resistance rates. As doxy-PEP is incorporated into clinical practice, an urgent unanswered question is whether increased doxycycline use will drive tetracycline-class resistance in Neisseria gonorrhoeae. Here, we report an updated RT-PCR molecular diagnostic to detect the tetM gene that confers high-level tetracycline resistance in N. gonorrhoeae.

Molecular surveillance to monitor the prevalence of tetracycline resistance in Neisseria gonorrhoeae.

Doxycycline post-exposure prophylaxis (Doxy-PEP) reduces bacterial sexually transmitted infections (STIs) but may select for tetracycline resistance in Neisseria gonorrhoeae and co-resistance to other antibiotics, including ceftriaxone.. The implementation of doxy-PEP should be accompanied by monitoring doxycycline resistance, but the optimal strategy to detect changes in the prevalence of resistance has not been established. We used a deterministic compartmental model of gonorrhea transmission to evaluate the performance of two strategies in providing early warning signals for rising resistance: (1) phenotypic testing of cultured isolates and (2) PCR for tetM in remnants from positive Nucleic Acid Amplification Tests (NAATs) used for gonorrhea diagnosis. For each strategy, we calculated the resistance proportion with 90% simulation intervals as well as the time under each sampling strategy to achieve 95% confidence that the resistance proportion exceeded a resistance threshold ranging from 11-30%. Given the substantially larger available sample size, PCR for tetM in remnant NAATs detected increased high-level tetracycline resistance with high confidence faster than phenotypic testing of cultured specimens. Our results suggest that population surveillance using molecular testing for tetM can complement culturebased surveillance of tetracycline resistance in N. gonorrhoeae and inform policy considerations for doxy-PEP.

Development of at-home sample collection logistics for large-scale seroprevalence studies.

BACKGROUND: Serological studies rely on the recruitment of representative cohorts; however, such efforts are specially complicated by the conditions surrounding the COVID19 pandemic. METHODS: We aimed to design and implement a fully remote methodology for conducting safe serological surveys that also allow for the engagement of representative study populations. RESULTS: This design was well-received and effective. 2,066 participants ≥18 years old were enrolled, reflecting the ethnic and racial composition of Massachusetts. >70% of them reported being satisfied/extremely satisfied with the online enrollment and at-home self-collection of blood samples. While 18.6% reported some discomfort experienced with the collection process, 72.2% stated that they would be willing to test weekly if enrolled in a long-term study. CONCLUSIONS: High engagement and positive feedback from participants, as well as the quality of self-collected specimens, point to the usefulness of this fully remote, self-collection-based study design for future safer and efficient population-level serological surveys.