Men and Women Have Similar Neisseria gonorrhoeae Bacterial Loads: a Comparison of Three Anatomical Sites

Abstract

Background Neisseria gonorrhoeae (NG) is a common bacterial sexually transmitted infection (STI). Currently, there are limited data on the bacterial load in both men and women, and on both genital and extra-genital sites. Therefore, we quantified NG bacterial load in a large population of women, heterosexual men, and men who have sex with men (MSM) at three different anatomical sites. Methods NG-positive samples (n=1265) of STI clinic consultations (n=944) were tested for NG with the Roche Cobas® 4800 system and Cq-values were used as an inversely proportional measure for NG bacterial load after interpolation from a standard curve. Bacterial load was compared between sample material and sex using t-tests. Results The following mean NG loads were observed: urine, 4.5 ±1.0 log10 CFU/mL; vaginal swabs, 4.3 ±1.1 log10 CFU/mL; anorectal swabs (women), 4.0 ±1.2 log10 CFU/mL; anorectal swabs (men), 4.5 ±1.3 log10 CFU/mL; oropharyngeal swabs (women), 2.8 ±0.9 log10 CFU/mL; and oropharyngeal swabs (men), 3.2 ±1.0 log10 CFU/mL. Oropharyngeal swabs had a significantly lower NG load (p<0.001) compared to genital and anorectal samples. Load did not differ between men and women. Conclusions This is the first study that determined NG load in both women and men at three anatomical sites. The substantial NG load at all sample sites suggest that all sites may have transmission potential. However, the oropharyngeal site presents the lowest bacterial load. Men and women have a similar NG load on separate anatomical sites arguing for similar transmission potential and similar clinical relevance.

Gonococcal bacterial load in PrEP users with Mycoplasma genitalium coinfection

“…[3][4][5][6] The small variations in NG bacterial loads between our and previous studies could be attributable to differences in sampling methods and analytical procedures. Similar to previous reports, NG bacterial load was higher in anorectal samples and urine compared with pharyngeal samples [3][4][5] and higher in symptomatic versus asymptomatic urogenital and anorectal (but not pharyngeal) infections. 5,6 We did not observe a significant association between NG bacterial load and age or repeated gonococcal infection.…”

“…2 Together, these data suggest that a higher NG bacterial load may represent a higher abundance of viable bacteria and a higher risk of transmission to sexual partners. 5,6 If bacterial load is a determinant of gonococcal infectivity or duration of infection, it is relevant to detail which factors are associated with higher NG bacterial load.…”

Pharmacodynamic Evaluation of Zoliflodacin Treatment of Neisseria gonorrhoeae Strains With Amino Acid Substitutions in the Zoliflodacin Target GyrB Using a Dynamic Hollow Fiber Infection Model

“…Briefly, on the first day 0.5 ml of N. gonorrhoeae cultures (18–24 h) from GCAGP agar plates ( Foerster et al, 2019 ) were inoculated in 49.5 ml of mFB and incubated at 36°C in a humidified 5% CO 2 -enriched atmosphere to mid-log phase. 10 ml (∼10 6 CFU/ml) of the N. gonorrhoeae suspension were then inoculated into each HFIM cartridge to mimic a clinically relevant N. gonorrhoeae cell concentration ( Bissessor et al, 2011 ; Chow et al, 2016 ; Priest et al, 2017 ; Van Der Veer et al, 2020 ). Zoliflodacin was administrated to mimic an adult human PK concentration-time profile following a single oral dose of zoliflodacin [PK parameters for zoliflodacin 3 g oral dose were used (linearly adjusted for other doses): 17% fraction of zoliflodacin free (protein-unbound) in plasma, 6.47 h half-life (t 1/2 ), and a 3 h infusion time] ( O’Donnell et al, 2019 ), as previously described ( Jacobsson et al, 2021 ).…”

Pharmacodynamic Evaluation of Dosing, Bacterial Kill, and Resistance Suppression for Zoliflodacin Against Neisseria gonorrhoeae in a Dynamic Hollow Fiber Infection Model

“…On the first day of the experiment, 0.5 ml of fresh N. gonorrhoeae cultures (18-24 h) from GCAGP agar plates (Foerster et al, 2019) were inoculated in 49.5 ml of mFB and incubated at 36°C in a humidified 5% CO 2 -enriched atmosphere to mid-log phase. 10 mL (quantified as ∼10 5 -10 6 CFU/ml in the different experiments) of the bacterial suspensions were inoculated into the extra-capillary space of each HFIM cartridge to simulate a clinically relevant N. gonorrhoeae burden in different anatomical sites of infection (Bissessor et al, 2011;Chow et al, 2016;Priest et al, 2017;Van Der Veer et al, 2020). Zoliflodacin was administrated to the HFIM via a syringe pump (New Era Pump Systems Inc., Farmingdale, NY, United States) programmed to mimic a fasted adult human protein-unbound PK concentration-time profile following a single oral zoliflodacin dose (PK parameters were used for oral dose of zoliflodacin 3 g (linear PK assumed throughout all doses evaluated): 17% protein-unbound fraction of zoliflodacin in human plasma, 6.47 h half-life (T 1/2 ), and a 3-h infusion time) (Study STI_Zoli002;O'Donnell et al, 2019).…”