Search

BACKGROUND Previous studies have shown substantial differences in geographic clustering of sexually transmitted infections (STI), such as chlamydia (CT) and gonorrhea (NG), conditional on epidemic phase. Chlamydia and NG have recently shown resurgent epidemiology in the northern hemisphere. This study describes the recent epidemiology of CT and NG in Winnipeg, Canada, combining traditional surveillance tools with place-based analyses, and comparing the ecological niches of CT and NG, in the context of their evolving epidemiology. METHODS Data were collected as part of routine public health surveillance between 2007 and 2016. Secular trends for CT and NG, and CT/NG coinfection were examined. Gini coefficients and population attributable fractions explored the distribution, and concentration of infections over time and space. RESULTS Rates of CT increased from 394.9/100,000 population to 476.2/100,000 population from 2007 to 2016. Gonorrhea rates increased from 78.0/100,000 population to 143.5/100,000 population during the same period. Each pathogen had its own ecological niche: CT was widespread geographically and socio-demographically, while NG was clustered in Winnipeg's inner-core. CT/NG co-infections had the narrowest space and age distribution. NG was shown to be undergoing a growth phase, with clear signs of geographic dispersion. The expansion of NG resembled the geographic distribution of CT. CONCLUSIONS We demonstrated that NG was experiencing a growth phase, confirming theoretical predictions of geographic dispersion during a growth phase. During this phase, NG occupied similar geographic spaces as CT. Knowledge of different ecological niches could lead to better targeting of resources for subpopulations vulnerable to STIs.

Real-time polymerase chain reaction (PCR) assays to detect antimicrobial resistance-associated mutations were tested on Neisseria gonorrhoeae-positive clinical samples with matched isolates. Of the nucleic acid amplification tests/cultures, 87.7% (64/73), 98.6% (72/73), and 98.4% (62/63) predicted cephalosporin, ciprofloxacin, and azithromycin susceptibilities, respectively. N. gonorrhoeae multiantigen sequence type was correctly predicted for 98.7% (79/80), and 13 of 58 N. gonorrhoeae-negative specimens showed false-positive results.

Background Methods for accessing large sexual networks are essential for investigating the mechanisms for the spread of sexually transmitted infections. Goal Four samples of cases were compared with the total population to determine which identified the largest networks. Study Design Individuals with positive test results for chlamydia during a 6-month period were selected from a laboratory database and linked with sex partner information from a notifiable disease registry. Sexual networks were constructed for a random sample, people with positive results from two or more tests for chlamydia, people with positive tests results for both gonorrhea and chlamydia, and the preceding two groups combined. Results The coinfected people combined with the repeaters yielded the highest proportion (47.8%) of large networks (>10 people), followed by the coinfected people, the repeaters, and finally the random sample. Conclusions People coinfected with chlamydia and gonorrhea and those with repeated chlamydial infection present ideal opportunities for both research and prevention.