Since early 2022, routine testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) based on symptoms and exposure history has largely ceased in Canada. Consequently, seroprevalence studies, particularly longitudinal studies, have become critical for monitoring the rate of incident SARS-CoV-2 infections and the proportion of the population with evidence of immunity. EnCORE is a longitudinal SARS-CoV-2 seroprevalence study comprising five rounds of serology testing from October 2020 to June 2023, in a sample of 2- to 17-year-olds (at baseline), recruited from daycares and schools in four neighbourhoods of Montreal, Canada. We report on SARS-CoV-2 incidence and seroprevalence among the 509 participants in the fifth and final round of the study. Seroprevalence of antibodies from either infection or vaccination was 98% (95 per cent confidence interval [CI]: 97, 99). The infection-acquired seroprevalence was 78% (95% CI: 73–82), and the incidence rate was 113 per 100 person-years (95% CI: 94–132), compared to the seroprevalence of 58% and the incidence rate of 133 per 100 person-years, respectively, in the fourth round of testing (mid–late 2022). Of the 131 participants newly seropositive for infection in Round 4, only 18 were seronegative for infection in Round 5 (median follow-up: 326 days).

Background: The Canadian Nosocomial Infection Surveillance Program (CNISP) observed increased mortality among neonatal intensive care unit (NICU) patients with central-line–associated bloodstream infection (CLABSI) starting in 2017. In this study, we compared NICU patients with CLABSIs before and after 2017, and quantified the impact of epidemiological factors on 30-day survival. Methods: We included 1,276 NICU patients from 8–16 participating CNISP hospitals from the pre-2017 period (2009–2016) and the post-2017 period (2017–2022) using standardized definitions and questionnaires. We used Cox regression modeling to assess the impact of age at date of positive culture, sex, birthweight, CLABSI microorganism, region of the country, and surveillance period (before 2017 vs after 2017) on time to 30-day all-cause mortality from date of positive culture. Gestational age was not available for this analysis. We reported model outputs as hazard ratios with 95% CIs. Results: In total, 769 (60%) NICU CLABSIs were reported in the pre-2017 period and 507 (40%) in the post-2017 period. The 30-day all-cause mortality rate was 8% (n = 100 of 1,276) overall, and significantly higher after 2017 (12%, n = 61 of 507) than before 2017 (5%, n = 39 of 769) (P < .001).

During the post-2017 period, cases were significantly younger: 16 days (IQR, 9–33) versus 21 days (IQR, 11–49) (P = .002). Median days from ICU admission to infection were shorter: 14 (IQR, 8–31) versus 19 (IQR, 10–41) (P < .001). More gram-negative CLABSIs were identified (29% vs 24%; P = .040) and fewer gram-positive CLABSIs were identified (64% vs 72%; P = .006) compared to the pre-2017 period. Mortality was higher in CLABSIs caused by gram-negative bacteria (15%, n = 50 of 328) than gram-positive bacteria (4.4%, n = 39 of 877) (P < .001), and mortality was higher in neonates with birthweight <1,000 g (11%, n = 71 of 673) compared to those weighing ≥1,000 g (5%, n = 28 of 560) (P < .001).

Adjusting for all other factors, survival modeling indicated that NICU CLABSIs identified in the post-2017 period had 2.12 (95% CI, 1.23–3.66) times the hazard ratio of 30-day all-cause mortality compared to those before 2017 (P < .006). Those identified with a gram-positive bacterium had a 0.28 hazard ratio (95% CI, 0.12–0.65) of 30-day mortality compared to those with a gram-negative bacterium or fungus (P = .003). In the fully adjusted model, age, sex, and birthweight were not significantly associated with NICU CLABSI survival. Conclusions: NICU patients with CLABSIs had significantly higher all-cause mortality between 2017–2022 compared to 2009–2016, and those who acquired gram-positive–associated CLABSIs had improved survival compared to other organisms. Further work is needed to identify and understand factors driving the increased mortality among NICU CLABSI patients from 2017–2022.

Disclosures: None

In a tertiary-care, pediatric healthcare center in Québec, Canada, healthcare workers who reported a household exposure to confirmed coronavirus disease 2019 (COVID-19) cases were allowed to work. On repeated testing, 15% became severe acute respiratory coronavirus virus 2 (SARS-CoV-2)–positive by reverse-transcription polymerase chain reaction (RT-PCR), with no nosocomial transmission. Being asymptomatic and receiving a booster dose >7 days prior to exposure was protective against becoming SARS-CoV-2–positive by PCR.

This document is part of the “SHEA Neonatal Intensive Care Unit (NICU) White Paper Series.” It is intended to provide practical, expert opinion, and/or evidence-based answers to frequently asked questions about CLABSI detection and prevention in the NICU. This document serves as a companion to the CDC Healthcare Infection Control Practices Advisory Committee (HICPAC) Guideline for Prevention of Infections in Neonatal Intensive Care Unit Patients. Central line-associated bloodstream infections (CLABSIs) are among the most frequent invasive infections among infants in the NICU and contribute to substantial morbidity and mortality. Infants who survive CLABSIs have prolonged hospitalization resulting in increased healthcare costs and suffer greater comorbidities including worse neurodevelopmental and growth outcomes. A bundled approach to central line care practices in the NICU has reduced CLABSI rates, but challenges remain. This document was authored by pediatric infectious diseases specialists, neonatologists, advanced practice nurse practitioners, infection preventionists, members of the HICPAC guideline-writing panel, and members of the SHEA Pediatric Leadership Council. For the selected topic areas, the authors provide practical approaches in question-and-answer format, with answers based on consensus expert opinion within the context of the literature search conducted for the companion HICPAC document and supplemented by other published information retrieved by the authors. Two documents in the series precede this one: “Practical approaches to Clostridioides difficile prevention” published in August 2018 and “Practical approaches to Staphylococcus aureus prevention,” published in September 2020.

Background: Sink drains can act as breeding grounds for multidrug-resistant (MDR) bacteria, leading to outbreaks. Drains provide a protected humid environment where nutrient-rich substances are available. Recent and growing installation of water and energy conservation devices have led to increased frequency of drain blockage due to biofilm accumulation. Ineffective drainage may lead to backflow and accumulation of water in the sink during use, increasing the risk of contaminated aerosols formation or direct contamination of surrounding material and equipment. Cleaning and disinfection procedures of sink drains need to be improved to prevent amplification and dispersion of MDR bacteria. The objective of this study was to investigate alternatives to reduce the biofilm and risk of contamination through aerosols. Methods: Sink drains from patient rooms were randomly selected in the neonatal intensive care unit of a 450-bed pediatric hospital. We tested 4 approaches: (1) new drain; (2) self-disinfecting heating-vibration drain; (3) chemical disinfection with 20 ppm chlorine for 30 minutes; and (4) thermal disinfection with > 90°C water for 30 minutes. A special device was used during disinfection to increase the disinfectant contact time with the biofilm. Treatments were conducted weekly, with prior sampling of drain water. Other drains were also sampled weekly, including a control drain with no intervention. Bacterial loads were evaluated using flow cytometry and heterotrophic plate counts. The drains were made of stainless steel, a heat-conductive material. Results: Preliminary results show that chlorine disinfection had a small impact (<1 log) on culturable bacteria at 48 hours after disinfection but not after a week or repeated weekly disinfection. Thermal disinfection using boiling water is promising, showing an important decrease of 4 log in culturable cells after 48 hours and a concentration still 100× lower 1 week after the disinfection. Repeated weekly thermal disinfection maintained lower culturable levels in the drain. No culturable cells were detected in water from the self-disinfecting drain 2 months after installation, whereas the new drain became fully colonized to concentrations similar to those of drains prior to interventions during the same period. Conclusions: Thermal disinfection of drains is a promising alternative to chlorine. This solution is interesting because it is nontoxic and easy to perform, requiring a small volume of hot water. The rapid recolonization of the new drain suggests that replacing contaminated drains is not a sustainable solution and would need to be paired with a thermal disinfection program to maintain low culturable cells.

Funding: No

Disclosures: None

Neuraminidase inhibitors (NAIs) are likely part of the rapid response and control in influenza pandemics and institutional outbreaks. We conducted a systematic review to appraise the current evidence on the use of NAIs among healthcare workers in the context of an influenza pandemic.

We performed viral culture of respiratory specimens in 118 severe acute respiratory coronavirus virus 2 (SARS-CoV-2)–infected healthcare workers (HCWs), ∼2 weeks after symptom onset. Only 1 HCW (0.8%) had a positive culture. No factors for prolonged viral shedding were identified. Infectivity is resolved in nearly all HCWs ∼2 weeks after symptom onset.

Background: Neurosurgeries are at high risk of surgical site infections (SSI), a complication associated with increased morbidity, mortality, and cost. Our aim was to measure SSI incidence and risk factors following pediatric neurosurgery at CHU Sainte-Justine, the provincial center for pediatric craniofacial surgery in Québec, Canada. Methods: Retrospective cohort study of all patients with elective neurosurgery performed at CHUSJ between October 2014 and October 2018. Medical records were reviewed to compare demographics, clinical presentations, and outcomes of patients. SSIs occurring within 30 days of a procedure without implant and up to 90 days with implant, were identified. SSI incidence was measured in patient years, and risk factors were assessed using univariate logistic regressions. Results: In total, 379 patients were included with an overall SSI incidence of 3.96 patient years. We found a higher SSI incidence in 2014–2015 compared to 2016–2018 (1.82 vs 4.83 patient years). The median age was 3.90 years, and cases seemed younger than controls (1.45 vs 4.15 years). No difference between groups was found for sex, body mass index, prematurity, and length of hospitalization. The proportion of deep SSIs was greater than superficial SSIs (53.3% vs 46.7%). Cases were more likely to present with a more severe ASA score, previous history of neurosurgery, neurological conditions, and pulmonary conditions than controls: OR, 3.90 (95% CI, 1.36–11.49); OR, 2.59 (95% CI, 0.88–7.40); OR, 2.77 (95% CI, 0.98–8.41), and OR, 3.21 (95% CI, 0.86–9.94), respectively. Among patients with history of neurosurgery, a higher proportion of cases experienced a cerebrospinal fluid leak (28.6% vs 2.2%). Most patients (85.8%) received preoperative prophylactic antibiotic. Of those, 49.3% were considered appropriate based on antibiotic and timing of administration. When antibiotic dosage was also considered, the number of patients who received an appropriate antibiotic therapy decreased radically. Conclusions: Patients with comorbidities, especially neurological and pulmonary conditions, are at higher risk of SSI after neurosurgery. We are currently working on a detailed analysis to explain the increase in SSI incidence after 2016. Finally, prophylactic antibiotic therapy needs to be improved and its impact on SSI rates needs to be monitored.

Funding: None

Disclosures: None

Background: Nosocomial infections cause 4%–56% mortality in newborns. Several epidemiological studies have shown that transmission of opportunistic pathogens from the sink to the patient, including Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Serratia marcescens are associated with nosocomial infections in neonatal intensive care units (NICUs). In this project, we aimed to develop fast, accurate, and high-throughput multilocus sequence typing assays (HiMLST-Illumina) to detect opportunistic pathogens to assess their distribution in the sink environment of NICUs and their transfer to patients. Methods: Genome sequences of P. aeruginosa (n = 45), S. maltophilia (n = 23) and S. marcescens (n = 34) strains were retrieved from public genome databases to build their pangenomes, using the open-source PGAdb-builder server. The core genome was identified for each opportunistic pathogen and was searched for genes displaying the highest polymorphism. The minimal number of loci to include in a HiMLST-Illumina assay was determined by comparing topology of phylogenetic trees of concatenated loci based on genome similarity, computed as the average nucleotide identity (ANI) score. The primers used for HiMLST-Illumina schemes were designed in silico on a conserved domain and were tested on reference strains of each species. Results: Bioinformatics analyses showed that 3–4 loci (<300 base pairs per locus) distinguished strains with the same performances than ANI scores. The assays were tested using opportunistic pathogen isolates and environmental DNA originating from NICU sinks. The HiMLST-Illumina analysis of environmental DNA revealed the presence of at least 1 of the 3 studied opportunistic pathogens in 50% of sampled drains (n = 20). In a previous sampling, P. aeruginosa was isolated on selective culture media before and 48 hours after disinfection of a sink drain with chlorine. S. marcescens was also isolated from another sink 2 weeks after disinfection. Identification of the isolates was confirmed by HiMLST-Illumina analyses and will be typed to compare with clinical isolates. Conclusions: Initial in silico tests predict a high discriminating power of the HiMLST-Illumina method, suggesting that it would be possible to quickly identify strains of interest in a large number of samples. The power of this method is also in the possibility for molecular typing without a need for cultivation. Preliminary results suggest that sinks are readily colonized by opportunistic pathogens. This HiMLST-Illumina scheme will be applied in a 2-year intensive survey of NICUs in 3 hospitals in Montreal to evaluate the performance of new sink designs in limiting bioaerosol production and transmission of opportunistic pathogens to patients.

Funding: None

Disclosures: None

Background: Rotavirus is a leading cause of viral acute gastroenteritis (AGE) in infants. Neonates hospitalized in neonatal intensive care units (NICUs) are at risk of rotavirus infections with severe outcomes. The administration of rotavirus vaccines is only recommended, in the United States and Canada, upon discharge from the NICU despite rotavirus vaccine being proven safe and effective in these populations, due to risks of live-attenuated vaccine administration in immunocompromised patients and theoretical risks of rotavirus vaccines strains shedding and transmission. We summarized recent evidence regarding rotavirus vaccines administration in the NICU setting and safety of rotavirus vaccines in preterm infants. Methods: We conducted a rapid review of the literature from the past 10 years, searching Medline and Embase, including all study types except reviews, reporting on rotavirus vaccine 1 and rotavirus vaccine 5; NICU setting; shedding or transmission; and/or safety in preterm. One reviewer performed data extraction and quality assessment. Results: In total, 31 articles were analyzed. Vaccine-derived virus shedding following rotavirus vaccination existed for nearly all infants, mostly during the first week after dose 1, with rare transmission described only in the household setting. No case of transmission in the NICU was reported. Adverse events were mild to moderate, occurring in 10%–60% of vaccinated infants. Extreme premature infants or with underlying gastrointestinal failure requiring surgery presented more severe adverse events. Conclusions: Recommendations regarding rotavirus vaccine administration in the NICU should be reassessed in light of the relative safety and absence of transmission of rotavirus vaccine strains in the NICU.

Funding: None

Disclosures: Sicard Mélanie: I reference the use of rotavirus vaccines in the NICU setting, which is not recommended; I discuss possible reassessment of these recommendations.

Background: In 2019, a measles community outbreak resulted in a secondary case in a health care worker (HCW) working in a pediatric hospital in Montral, Canada. Following the event, HCWs were screened to identify individuals susceptible to measles infection based on serology results. Objective: Our aim was to assess measles seroprotection rates and to evaluate vaccine responses of susceptible HCWs using commercial enzyme immunoassay (EIA) or enzyme linked immunosorbent assay (ELISA). Methods: Emergency department (ED) employees, including doctors, were screened for measles susceptibility as part of a postoutbreak measure by the hospital occupational health service. Demographic information was collected. Measles history and vaccination information were collected using a personal vaccination booklet, employee vaccination profile, or the Qubec vaccination registry. According to the Quebec Immunization Protocol (PIQ), individuals born before 1970, or who have received 2 doses of a measles-containing vaccines are considered protected. Individuals with undetectable or equivocal antibody levels were considered at risk of measles infection. These individuals were offered vaccination and were tested for vaccine response 4 weeks after vaccination. Results: Anti-IgG measles antibody results, demographic information, and vaccination information were obtained for 257 employees. The results are currently available for 233 HCWs: 224 HCWs (96%) were seropositive, 7 (3%) were seronegative, and 2 were equivocal. Among seronegative individuals, 6 (85.7%) were born after 1980 and 3 (42.9%) had received 2 doses of a measles-containing vaccine. Of those with an equivocal result, 1 (50%) had received 2 doses and 1 (50%), born after 1970, did not confirm vaccination status. Finally, 9 (4%) of seropositive individuals were not vaccinated; of whom 8 (88.9%) were born before 1970. Conclusions: Our preliminary results suggest that the 95% immunity threshold that is usually required to prevent secondary transmission of measles has been reached in our ED HCW cohort. Even years after the second MMR dose, HCWs remain well protected. Relying on documented vaccination status is thus acceptable.

Funding: None

Disclosures: None

We performed a molecular and epidemiologic study of a healthcare-associated rhinovirus outbreak to better understand transmission in neonatal intensive care settings. Sequencing of the 7 outbreak strains revealed 4 distinct clades, indicating multiple sources. A single clade infected 3 patients in adjacent rooms, suggesting horizontal transmission. We observed 1 rhinovirus-associated death.