Predictors of Gonorrhea Reinfection in a Cohort of Sexually Transmitted Disease Patients in Alberta, Canada, 1991–2003

A pair formation model with recovery: Application to mpox

The current global outbreaks of mpox is a unique infectious disease in the way it seems to be transmitting: it has been observed to be highly concentrated in communities of men who have sex with men (MSM) through pair formation, and also provides long lasting immunity. This framework of mostly close, prolonged contact spreading a disease that admits immunity after infection is unlike similar infections which either offer little to no immunity post-infection or are lifelong infections. This creates the need for a new model framework that incorporates pair formation structure with recovery. While seemingly a straight forward model, we show how new dynamics arise from the combination of pair formation and recovery that are not present in a standard model with recovery and also not present in a pair formation model without recovery. We see that the combination of these two properties allows for waves of infection that are not seen in a standard SIR model. These dynamics suggest that outbreaks of mpox around the world may require special attention from public health. We also derive a reproduction number for this model and estimate the reproduction number of human mpox to be ≈2.3 using global and Canadian data. The expression derived for R0 can help estimate key parameters for diseases transmission and public health interventions and compare to equivalent models without pair formation.

Incidence and risk factors of gonococcal urethritis reinfection among Thai male patients in a multicenter, retrospective cohort study

Gonococcal urethritis (GU) is the second most common sexually transmitted infection (STI). Epidemiologic studies of the situation of GU reinfection and its related risk factors among patients with a history of GU in Thailand remain somewhat limited. A hospital-based retrospective cohort study was conducted between January 1, 2010 and December 31, 2020 to determine the incidence and risk factors of GU reinfection among male patients visiting in Royal Thai Army (RTA) Hospitals. A total of 2,465 male patients presenting a history of GU was included in this study. In all, 147 (6.0%; 95% CI 5.1–6.9) male patients presented GU reinfection, representing an incidence rate of 1.3 (95% CI 1.1–1.5) per 100 person-years. The independent risk factors for GU reinfection were age < 30 years (AHR 1.7; 95% CI 1.0–2.8), number of sexual partners equal to 2 (AHR 3.4; 95% CI 1.0–11.2), \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\ge$$\end{document}≥ 3 (AHR 5.6; 95% CI 2.7–11.6), and participants residing in the north (AHR 4.1; 95% CI 2.3–7.5) and northeast regions (AHR 2.1; 95% CI 1.1–3.9). Incidence of GU reinfection among male patients visiting RTA Hospitals was significantly high among younger aged patients, especially in the north and northeast regions. Multiple sex partners played a major role in GU reinfection. Effective STI prevention programs should be provided to alleviate reinfection and its complications.

Increasing Chlamydia and Gonorrhea Infections among Female Juveniles: The Need for Collaboration to Improve Treatment

Background: Youth in juvenile detention centers are at a high risk for sexually transmitted disease (STD). The current study assesses the trends of chlamydia and gonorrhea (GC) infections and treatment among females within a single county’s juvenile correctional facilities.

Methods: This is a retrospective review of aggregate data of female adolescents between 12 and 18 years old who underwent STD screening from 2009 to 2016 in San Bernardino County.

Results: Chlamydia infections among adolescent females increased from 11.8% in 2009 to 17.0% in 2016 (p = 0.0002), and GC infections increased from 1.3% in 2009 to 6.0% in 2016 (p < 0.0001). Treatment rates of chlamydia were stable, ranging from 66.7% to 70.8% of positive female adolescents were treated between 2009 and 2016 (p=0.1752). The treatment rate for GC increased from 33% in 2009 to 78.3% in 2016, but annual trends were not statistically significant (p=0.8419).

Conclusions: Chlamydia and GC infections among female adolescents discovered during routine screening upon booking into a county juvenile detention system increased over the study time period. Effective collaboration between public health and various community organizations is needed to improve awareness and prevention of STDs amongst at-risk adolescents.

Repeat infection with Neisseria gonorrhoeae among active duty U.S. Army personnel: a population-based case-series study

Little information is known on the rate of repeat gonorrhea infection among U.S. military personnel. We analyzed all gonorrhea cases reported to the Defense Medical Surveillance System during 2006–2012 to determine the rate of repeat infection. During the seven-year study period, 17,602 active duty U.S. Army personnel with a first incident gonorrhea infection were reported. Among the 4987 women with a first gonorrhea infection, 14.4% had at least one repeat infection. Among the 12,615 men with a first gonorrhea infection, 13.7% had at least one repeat infection. Overall, the rate of repeat gonorrhea infection was 44.5 and 48.9 per 1000 person-years for women and men, respectively. Service members aged 17–19 years (hazard ratio [HR] for women = 1.51; HR for men = 1.71), African-American personnel (HR for women = 1.26; HR for men = 2.17), junior enlisted personnel (HR for women = 2.64; HR for men = 1.37), and those with one year or less of service (HR for women = 1.23; HR for men = 1.37) were at higher risk of repeat infection. The findings from this study highlight the need to develop targeted prevention initiatives including education, counseling, and retesting to prevent gonorrhea reinfections among U.S. Army personnel.

An exploratory analysis of individuals with multiple episodes of different reportable diseases, Montreal, 1990-2012

OBJECTIVES

Studies of public health reporting have only examined multiple episodes of the same communicable disease within an individual. We aimed to characterize Montreal residents with multiple reportable disease episodes from 1990 to 2012, while accounting for all types of reportable diseases.

STUDY DESIGN

Retrospective cohort study.

METHODS

We performed an exploratory analysis using descriptive statistics, contingency tables, and logistic regression.

RESULTS

There were 157,839 individuals with at least one disease report and a total of 179,455 disease reports. The 9.8% of subjects with more than one episode accounted for 20.7% of all reported episodes. Among subjects with four or fewer episodes, 54.0% were women, while 74.3% of subjects with five or more episodes were men. Subjects with multiple episodes were more likely to be reported for sexually transmitted infections than were persons with a single episode [difference of proportions: 10.4% (95% CI: 10.0%-10.9%)] and to reside in the neighbourhood encompassing Montreal's gay village.

CONCLUSIONS

Individuals with multiple communicable disease reports place a large burden on public health officials. These results may help guide investigation and prevention efforts to reduce the number of excess episodes.

Retreatment rates for uncomplicated gonorrhea infection: comparing ceftriaxone and azithromycin versus ceftriaxone and doxycycline

BACKGROUND

The current recommended first-line regimen to treat gonorrhea is ceftriaxone in combination with either azithromycin or doxycycline. Azithromycin is the preferred second agent. We retrospectively measured and compared gonorrhea retreatment rates between patients receiving ceftriaxone plus azithromycin and those receiving ceftriaxone plus doxycycline.

METHODS

Using data from public sexually transmitted disease clinics for patients treated for gonorrhea in Baltimore, Maryland, between January 2004 and December 2011, we measured time to retreatment from the date the ceftriaxone regimen was received. Censoring occurred on the earlier of 2 years posttreatment or March 31, 2012. Survival analysis methods were used to compare retreatment rates.

RESULTS

One tenth (9.9%; n = 4457) of patients were retreated within 2 years. Treatment regimen was not related to time to retreatment (adjusted hazard ratio [aHR], 0.88; 95% confidence interval, 0.69-1.12). Patients receiving expedited partner therapy (EPT) were 45% less likely to be retreated (aHR, 0.55 [0.31-0.96]) compared with patients treated before EPT became available. A subanalysis among patients retested for gonorrhea within 90 and 30 days found retreatment rates of 18.8% (n = 91/485) and 13.5% (n = 19/140), respectively. The 90-day cohort showed no association with treatment regimen (aHR, 0.95 [0.55-1.65]); however, all of the retreated patients in the 30-day cohort had received the doxycycline regimen.

CONCLUSIONS

Gonorrhea retreatment was common, highlighting the need for rescreening and better partner therapies. The protective effect of EPT further underscores the need for effective oral therapies. Azithromycin may be preferable as the second agent to treat gonorrhea, although doxycycline seems to be a reasonable alternative.

Demographic and behavioural characteristics predict bacterial STI reinfection and coinfection among a cross-sectional sample of laboratory-confirmed gonorrhea cases in a local health region from Saskatchewan, Canada

OBJECTIVES

We aimed to identify demographic and behavioural determinants associated with risk of repeat STI infection and coinfection with gonorrhea and chlamydia in the Regina Qu'Appelle Health Region, Saskatchewan.

METHODS

We extracted data from a cross-sectional sample of laboratory confirmed gonorrhea cases between 2003 and 2012 from the notifiable disease files of the Regina Qu'Appelle Health Region. Risk factors for repeater status were examined using logistic regression and for coinfection with gonorrhea and chlamydia using mixed-effects logistic regression to account for multiple diagnoses for individual clients.

RESULTS

Data from 1,143 cases (representing 1,027 unique individuals) and 1,524 reported contacts (representing 1,383 unique individuals) were extracted from the 10-year period. Factors associated with repeat infection entries in the database included younger age at first visit (p = 0.01), coinfection (p = 0.01), and sex trade involvement (p &lt; 0.01). Factors associated with coinfection at the time of diagnosis included younger age at diagnosis (p &lt; 0.001) and reported alcohol or drug abuse (p = 0.04).

CONCLUSION

In one of the first epidemiologic studies on gonorrhea in Saskatchewan, we have identified age, engagement in the sex trade, and drug and alcohol abuse as potential markers to identify clients with a high risk of reinfection and coinfection in the Regina Qu'Appelle Health Region. This information can help health care professionals in Saskatchewan's urban centres personalize their approach to counselling and treatment to optimize patient outcomes and disease control efforts, including potentially using expedited partner therapy and/or dual therapy where indicated.

Demographic and behavioural characteristics predict bacterial STI reinfection and coinfection among a cross-sectional sample of laboratory-confirmed gonorrhea cases in a local health region from Saskatchewan, Canada

OBJECTIVES

We aimed to identify demographic and behavioural determinants associated with risk of repeat STI infection and coinfection with gonorrhea and chlamydia in the Regina Qu'Appelle Health Region, Saskatchewan.

METHODS

We extracted data from a cross-sectional sample of laboratory confirmed gonorrhea cases between 2003 and 2012 from the notifiable disease files of the Regina Qu'Appelle Health Region. Risk factors for repeater status were examined using logistic regression and for coinfection with gonorrhea and chlamydia using mixed-effects logistic regression to account for multiple diagnoses for individual clients.

RESULTS

Data from 1,143 cases (representing 1,027 unique individuals) and 1,524 reported contacts (representing 1,383 unique individuals) were extracted from the 10-year period. Factors associated with repeat infection entries in the database included younger age at first visit (p = 0.01), coinfection (p = 0.01), and sex trade involvement (p &lt; 0.01). Factors associated with coinfection at the time of diagnosis included younger age at diagnosis (p &lt; 0.001) and reported alcohol or drug abuse (p = 0.04).

CONCLUSION

In one of the first epidemiologic studies on gonorrhea in Saskatchewan, we have identified age, engagement in the sex trade, and drug and alcohol abuse as potential markers to identify clients with a high risk of reinfection and coinfection in the Regina Qu'Appelle Health Region. This information can help health care professionals in Saskatchewan's urban centres personalize their approach to counselling and treatment to optimize patient outcomes and disease control efforts, including potentially using expedited partner therapy and/or dual therapy where indicated.

Detecting re-infection in patients after an initial diagnosis of gonorrhoea: is routine recall for re-screening useful?

To assess the outcome of routine sexually transmitted infection re-screening after a three-month interval in unselected patients diagnosed with gonorrhoea, we sought to assess whether this active approach would result in an increase in the number of people attending clinic and subsequently diagnosed with gonorrhoea re-infection, compared with normal re-presentation rates. A recall group of patients were invited for re-screening three months after their initial diagnosis of gonorrhoea. Permission was sought to send a reminder two weeks prior to their scheduled recall appointment. Comparisons were made with a historical control group of patients with gonorrhoea in the absence of any formal recall. Of the 242 patients in the intervention arm, 96 (40%) re-attended within six months, and 15 (6%) tested gonorrhoea positive. Two hundred and two patients were assessed in the control group, of whom 45 (22%) re-attended within six months, and 13 (6%) tested gonorrhoea positive. Women were more likely than men to re-attend following active recall, but they were not at higher risk of re-attending while re-infected with gonorrhoea. Active recall following a gonorrhoea diagnosis significantly increases re-attendance rates for repeat screening but did not result in an increased number of subsequent gonorrhoea diagnoses.

A partner-related risk behavior index to identify people at elevated risk for sexually transmitted infections

The purpose of this study was to develop and test a sexual-partner-related risk behavior index to identify high-risk individuals most likely to have a sexually transmitted infection (STI). Patients from five STI and adolescent medical clinics in three US cities were recruited (N = 928; M age = 29.2 years). Data were collected using audio-computer-assisted self-interviewing. Of seven sexual-partner-related variables, those that were significantly associated with the outcomes were combined into a partner-related risk behavior index. The dependent variables were laboratory-confirmed infection with Chlamydia trachomatis, Neisseria gonorrhoeae, and/or Trichomonas vaginalis. Nearly one-fifth of the sample (169/928; 18.4%) tested positive for an STI. Three of the seven items were significantly associated with having one or more STIs: sex with a newly released prisoner, sex with a person known or suspected of having an STI, and sexual concurrency. In combined form, this three-item index was significantly associated with STI prevalence (p < .001). In the presence of three covariates (gender, race, and age), those classified as being at-risk by the index were 1.8 times more likely than those not classified as such to test positive for an STI (p < .001). Among individuals at risk for STIs, a three-item index predicted testing positive for one or more of three STIs. This index could be used to prioritize and guide intensified clinic-based counseling for high-risk patients of STI and other clinics.

HIV incidence and prevalence among aboriginal peoples in Canada

We examined incidence, prevalence, and correlates of HIV infection in Aboriginal peoples in Canada and found that among most risk groups both Aboriginal and non-Aboriginal participants showed similar levels of HIV prevalence. Aboriginal peoples who use illicit drugs were found to have higher HIV incidence and prevalence when compared to their non-Aboriginal drug-using peers. Aboriginal street youth and female sex workers were also found to have higher HIV prevalence. Among Aboriginal populations, correlates of HIV-positive sero-status include syringe sharing and frequently injecting drugs, as well as geographic and social factors such as living in Vancouver or having a history of non-consensual sex. This study is relevant to Canada and elsewhere, as Indigenous populations are disproportionately represented in the HIV epidemic worldwide.

Risk factors and algorithms for chlamydial and gonococcal cervical infections in women attending family planning clinics in Thailand

AIM

To identify risk factors associated with and evaluate algorithms for predicting Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) cervical infections in women attending family planning clinics in Thailand.

METHODS

Eligible women were recruited from family planning clinics from all regions in Thailand. The women were followed at 3-month intervals for 15-24 months. At each visit, the women were interviewed for interval sexually transmitted infection (STI) history in the past 3 months, recent sexual behavior, and contraceptive use. Pelvic examinations were performed and endocervical specimens were collected to test for CT and NG using polymerase chain reaction.

RESULTS

Factors associated with incident CT/NG cervical infections in multivariate analyses included region of country other than the north, age <or=25 years, polygamous marriage, acquiring a new sex partner in the last 3 months, abnormal vaginal discharge, mucopurulent cervical discharge, and easily induced bleeding of the endocervix. Three models were developed to predict cervical infection. A model incorporating demographic factors and sexual behaviors had a sensitivity of 61% and a specificity of 71%. Incorporating additional factors did not materially improve test performance. Positive predictive values for all models evaluated were low.

CONCLUSION

In resource-limited settings, algorithmic approaches to identifying incident cervical infections among low-risk women may assist providers in the management of these infections.

Repeat infection with Chlamydia and gonorrhea among females: a systematic review of the literature

Determining the magnitude of chlamydia and gonorrhea reinfection is critical to inform evidence-based clinical practice guidelines related to retesting after treatment. PubMed was used to identify peer-reviewed English language studies published in the past 30 years that estimated reinfection rates among females treated for chlamydia or gonorrhea. Included in this analysis were original studies conducted in the United States and other industrialized countries that reported data on chlamydia or gonorrhea reinfection in females. Studies were stratified into 3 tiers based on study design. Reinfection rates were examined in relation to the organism, study design, length of follow-up, and population characteristics. Of the 47 studies included, 16 were active cohort (Tier 1), 15 passive cohort (Tier 2), and 16 disease registry (Tier 3) studies. The overall median proportion of females reinfected with chlamydia was 13.9% (n = 38 studies). Modeled chlamydia reinfection within 12 months demonstrated peak rates of 19% to 20% at 8 to 10 months. The overall median proportion of females reinfected with gonorrhea was 11.7% (n = 17 studies). Younger age was associated with higher rates of both chlamydia and gonorrhea reinfection. High rates of reinfection with chlamydia and gonorrhea among females, along with practical considerations, warrant retesting 3 to 6 months after treatment of the initial infection. Further research should investigate effective interventions to reduce reinfection and to increase retesting.