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Background There is a need to understand the duration of infectivity of primary and recurrent coronavirus disease 2019 (COVID-19) and identify predictors of loss of infectivity. Methods Prospective observational cohort study with serial viral culture, rapid antigen detection test (RADT) and reverse transcription polymerase chain reaction (RT-PCR) on nasopharyngeal specimens of healthcare workers with COVID-19. The primary outcome was viral culture positivity as indicative of infectivity. Predictors of loss of infectivity were determined using multivariate regression model. The performance of the US Centers for Disease Control and Prevention (CDC) criteria (fever resolution, symptom improvement, and negative RADT) to predict loss of infectivity was also investigated. Results In total, 121 participants (91 female [79.3%]; average age, 40 years) were enrolled. Most (n = 107, 88.4%) had received ≥3 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine doses, and 20 (16.5%) had COVID-19 previously. Viral culture positivity decreased from 71.9% (87/121) on day 5 of infection to 18.2% (22/121) on day 10. Participants with recurrent COVID-19 had a lower likelihood of infectivity than those with primary COVID-19 at each follow-up (day 5 odds ratio [OR], 0.14; P <.001]; day 7 OR, 0.04; P =.003]) and were all non-infective by day 10 (P =.02). Independent predictors of infectivity included prior COVID-19 (adjusted OR [aOR] on day 5, 0.005; P =.003), an RT-PCR cycle threshold [Ct] value <23 (aOR on day 5, 22.75; P <.001) but not symptom improvement or RADT result. The CDC criteria would identify 36% (24/67) of all non-infectious individuals on day 7. However, 17% (5/29) of those meeting all the criteria had a positive viral culture. Conclusions Infectivity of recurrent COVID-19 is shorter than primary infections. Loss of infectivity algorithms could be optimized. [ABSTRACT FROM AUTHOR]

Introduction During the 2022 mpox outbreak, the province of Quebec, Canada, prioritized first doses for pre-exposure vaccination of people at high mpox risk, delaying second doses due to limited supply. We estimated single-dose mpox vaccine effectiveness (VE) adjusting for virus exposure risk based only on surrogate indicators available within administrative databases (eg, clinical record of sexually transmitted infections) or supplemented by self-reported risk factor information (eg, sexual contacts). Methods We conducted a test-negative case-control study between 19 June and 24 September 2022. Information from administrative databases was supplemented by questionnaire collection of self-reported risk factors specific to the 3-week period before testing. Two study populations were assessed: all within the administrative databases (All-Admin) and the subset completing the questionnaire (Sub-Quest). Logistic regression models adjusted for age, calendar-time and exposure-risk, the latter based on administrative indicators only (All-Admin and Sub-Quest) or with questionnaire supplementation (Sub-Quest). Results There were 532 All-Admin participants, of which 199 (37%) belonged to Sub-Quest. With exposure-risk adjustment based only on administrative indicators, single-dose VE estimates were similar among All-Admin and Sub-Quest populations at 35% (95% confidence interval [CI]:−2 to 59) and 30% (95% CI:−38 to 64), respectively. With adjustment supplemented by questionnaire information, the Sub-Quest VE estimate increased to 65% (95% CI:1–87), with overlapping confidence intervals. Conclusions Using only administrative data, we estimate one vaccine dose reduced the mpox risk by about one-third; whereas, additionally adjusting for self-reported risk factor information revealed greater vaccine benefit, with one dose instead estimated to reduce the mpox risk by about two-thirds. Inadequate exposure-risk adjustment may substantially under-estimate mpox VE. [ABSTRACT FROM AUTHOR]

Ceftriaxone is one of the last remaining treatments available for gonorrhea and a component of the recommended dual therapy with azithromycin in Canada (1). As of October 15, 2017, only [...]

Background: Tecovirimat (TCV, TPOXX®) is an orthopox-specific antiviral drug indicated for the treatment of smallpox. There is also a mechanistic basis for its use in mpox infection. However, its approval was based on animal studies, and its efficacy and side-effect profile in human patients with disease is unknown. Methods: During the 2022 international mpox epidemic, clinicians in Canada were permitted by Health Canada to access TCV for severe cases of mpox disease. We describe the use of TCV in nine adults with severe mpox virus infection in Montréal, Canada. Results: Five patients were treated for severe and potentially life-threatening head and neck symptoms, while four were treated for genitourinary or anorectal disease. Two-thirds of patients were also treated for suspected bacterial superinfection. All patients recovered (median time to resolution of severe symptoms: nine days) without relapse or hospital readmission. No patients reported adverse events attributable to TCV and no patients stopped their treatment early. Conclusion: Our experience suggests that TCV is well tolerated and may accelerate recovery in severe cases. These preliminary, observational data may also be explained by concomitant treatment for superinfection and are limited by the absence of a control group. Controlled, clinical trials should be conducted to clarify the attributable benefit of TCV in severe mpox infection. [ABSTRACT FROM AUTHOR]

Studies have reported human bocavirus (HBoV) in children with respiratory tract infections (RTIs), but only occasionally in adults. We searched for HBoV DNA in nasopharyngeal aspirates (NPAs) from adults with [...]

Respiratory tract illnesses are a major cause of illness and death among elderly persons, especially those in long-term care facilities. Although the most commonly identified viruses have been influenza virus [...]

Objectives: To investigate a persistent multispecies OXA-204 outbreak occurring simultaneously in multiple distant hospitals in the province of Quebec, Canada.Methods: OXA-204 carbapenemase-producing Enterobacterales (CPE) isolated from multiple hospitals between January 2016 and October 2018 were included in the study. An epidemiological inquiry was conducted in order to elucidate possible transmission routes and a putative source. Isolates were characterized by standardized antibiotic susceptibility testing and by WGS, using Illumina short-read data and MinION long-read data.Results: The outbreak comprised 65 patients and 82 isolates from four hospital sites. Most patients were ≥65 years old, had multiple comorbidities and had received antibiotics recently. The infection to colonization ratio was 1:20. No persistent environmental reservoir was identified. The most frequent organism was Citrobacter freundii (n = 78), followed by Klebsiella spp. (n = 3) and Escherichia coli (n = 1). WGS analysis showed 77/78 C. freundii isolates differing by 0-26 single nucleotide variants (SNVs). Results of WGS analysis showed blaOXA-204 was present on three plasmids types (IncX1, IncA/C2 and IncFII/FIB/A/C2) and on a prophage. All C. freundii isolates harboured multiple copies of blaOXA-204, both on the chromosome and a plasmid. Plasmid IncFII/FIB/A/C2 was observed in all three species.Conclusions: Transfer of OXA-204 plasmids likely occurred between species within the same patient, highlighting the plasticity of these plasmids and potential for widespread dissemination. OXA-204 carbapenemase has been introduced into Quebec and has rapidly disseminated. Although the infection to colonization ratio was low in this outbreak, this carbapenemase has been associated with severe infection elsewhere. [ABSTRACT FROM AUTHOR]

Background Asymptomatic patients colonized with Clostridioides difficile are at risk of developing C. difficile infection (CDI), but the factors associated with disease onset are poorly understood. Our aims were to identify predictors of hospital-onset CDI (HO-CDI) among colonized patients and to explore the potential benefits of primary prophylaxis to prevent CDI. Methods We conducted a retrospective cohort study in a tertiary academic institution. Colonized patients were identified by detecting the tcdB gene by polymerase chain reaction on a rectal swab. Univariate and multivariate logistic regression analyses were used to identify predictors of HO-CDI. Results There were 19 112 patients screened, from which 960 (5%) colonized patients were identified: 513 met the inclusion criteria. Overall, 39 (7.6%) developed a HO-CDI, with a 30-day attributable mortality of 15%. An increasing length of stay (adjusted odds ratio [aOR] per day, 1.03; P =.006), exposure to multiple classes of antibiotics (aOR per class, 1.45; P =.02), use of opioids (aOR, 2.78; P =.007), and cirrhosis (aOR 5.49; P =.008) were independently associated with increased risks of HO-CDI, whereas the use of laxatives was associated with a lower risk of CDI (aOR 0.36; P =.01). Among the antimicrobials, B-lactam with B-lactamase inhibitors (OR 3.65; P <.001), first-generation cephalosporins (OR 2.38; P =.03), and carbapenems (OR 2.44; P =.03) correlated with the greatest risk of HO-CDI. By contrast, patient age, the use of proton pump inhibitors, and the use of primary prophylaxis were not significant predictors of HO-CDI. Conclusions This study identifies several factors that are associated with CDI among colonized patients. Whether modifying these variables could decrease the risk of CDI should be investigated. [ABSTRACT FROM AUTHOR]