Infection In Canada Research Articles

One Health Genomic Analysis of Extended-Spectrum β-Lactamase‒Producing Salmonella enterica, Canada, 2012‒2016.

Extended-spectrum β-lactamases (ESBLs) confer resistance to extended-spectrum cephalosporins, a major class of clinical antimicrobial drugs. We used genomic analysis to investigate whether domestic food animals, retail meat, and pets were reservoirs of ESBL-producing Salmonella for human infection in Canada. Of 30,303 Salmonella isolates tested during 2012–2016, we detected 95 ESBL producers. ESBL serotypes and alleles were mostly different between humans (n = 54) and animals/meat (n = 41). Two exceptions were blaSHV-2 and blaCTX-M-1 IncI1 plasmids, which were found in both sources. A subclade of S. enterica serovar Heidelberg isolates carrying the same IncI1-blaSHV-2 plasmid differed by only 1–7 single nucleotide variants. The most common ESBL producer in humans was Salmonella Infantis carrying blaCTX-M-65, which has since emerged in poultry in other countries. There were few instances of similar isolates and plasmids, suggesting that domestic animals and retail meat might have been minor reservoirs of ESBL-producing Salmonella for human infection.

Canada's response to the initial 2 years of the COVID-19 pandemic: a comparison with peer countries.

KEY POINTS The first known diagnosis of SARS-CoV-2 infection in Canada was in a patient in hospital in Toronto on Jan. 25, 2020.[1][1] At the time, few anticipated the intensity and duration of the COVID-19 pandemic, which has presented health systems and governments globally with challenges not

Epidemiology of invasive meningococcal disease in Canada, 2012-2019.

A variety of routine childhood and adolescent meningococcal vaccination programs using monovalent (serogroup C) and quadrivalent (A, C, Y, W) conjugate vaccines have been implemented in Canada since 2002, resulting in a decrease in invasive meningococcal disease (IMD) incidence, particularly in serogroup C. Meningococcal vaccines have also been used for outbreak response, including the multicomponent vaccine serogroup B vaccine. This report describes the epidemiology of IMD in Canada from 2012 to 2019. Case data were obtained from the National Enhanced IMD Surveillance System between January 1, 2012 and December 31, 2019. Isolates were sent to the National Microbiology Laboratory for confirmation of serogroup and further studies including phenotype and clonal complex identification. A total of 983 cases of IMD were reported between 2012 and 2019. Overall, the age-adjusted incidence of IMD from 2012 to 2019 was 0.34 cases per 100,000 population per year when standardized to the Canadian 2011 population age distribution (95% CI: 0.32-0.36). Infants younger than one year of age had the highest average age-specific incidence rate (3.6 cases per 100,000 population per year, 95% CI: 2.8-4.3). The highest age-adjusted incidence rate was associated with serogroup B (0.17 cases per 100, 000 population per year, 95% CI: 0.16-0.19). Prior to 2015, most invasive serogroup W isolates were identified as clonal complex 22 (ST-22 CC) and the increase in serogroup W in Canada in recent years has been associated with the replacement of the endemic ST-22 CC with the hyper-virulent ST-11 CC. Invasive meningococcal disease is a rare but severe infection in Canada that mostly affects the very young. Serogroup B continues to account for the greatest proportion of disease. Serogroup W associated with ST-11 CC is becoming a growing contributor of disease in all age groups not protected by serogroup W-containing vaccines.

Molecular epidemiology and clinical characteristics of hepatitis D virus infection in Canada

Background & AimsHDV affects 4.5–13% of chronic hepatitis B (CHB) patients globally, yet the prevalence of HDV infection in Canada is unknown. To investigate the prevalence, genotype, demographics, and clinical characteristics of HDV in Canada, we conducted a retrospective analysis of (1) HDV antibody and RNA positivity among referred specimens, and (2) a cross-sectional subset study of 135 HDV seropositive +/-RNA (HDV+) patients compared with 5,132 HBV mono-infected patients in the Canadian HBV Network.MethodsAnti-HDV IgG-positive specimens collected between 2012 and 2019 were RNA tested and the genotype determined. Patients enrolled in the Canadian HBV Network were >18 years of age and HBsAg-positive. Clinical data collected included risk factors, demographics, comorbidities, treatment, fibrosis assessment, and hepatic complications.ResultsOf the referred patients, 338/7,080 (4.8%, 95% CI 4.3–5.3) were HDV seropositive, with 219/338 RNA-positive (64.8%, 95% CI 59.6–69.7). The HDV+ cohort were more likely to be born in Canada, to be White or Black/African/Caribbean than Asian, and reporting high-risk behaviours, compared with HBV mono-infected patients. Cirrhosis, complications of end-stage liver disease, and liver transplantation were significantly more frequent in the HDV+ cohort. HDV viraemia was significantly associated with elevated liver transaminases and cirrhosis. Five HDV genotypes were observed among referred patients but no association between genotype and clinical outcome was detected within the HDV+ cohort.ConclusionsNearly 5% of the Canadian HBV referral population is HDV seropositive. HDV infection is highly associated with risk behaviours and both domestic and foreign-born patients with CHB. HDV was significantly associated with progressive liver disease highlighting the need for increased screening and surveillance of HDV in Canada.Lay summaryEvidence of HDV infection was observed in approximately 5% of Canadians who were infected with HBV referred to medical specialists. HDV-positive patients were more likely to be male, born in Canada, or White or Black/African/Caribbean compared to Asian, and to have reported high-risk activities such as injection or intranasal drug use or high-risk sexual contact compared with patients infected with only HBV. Patients infected with HDV were also more likely to suffer severe liver disease, including liver cancer, compared with HBV mono-infected patients.

Assessment of SARS-CoV-2 Seropositivity During the First and Second Viral Waves in 2020 and 2021 Among Canadian Adults

The incidence of infection during SARS-CoV-2 viral waves, the factors associated with infection, and the durability of antibody responses to infection among Canadian adults remain undocumented. To assess the cumulative incidence of SARS-CoV-2 infection during the first 2 viral waves in Canada by measuring seropositivity among adults. The Action to Beat Coronavirus study conducted 2 rounds of an online survey about COVID-19 experience and analyzed immunoglobulin G levels based on participant-collected dried blood spots (DBS) to assess the cumulative incidence of SARS-CoV-2 infection during the first and second viral waves in Canada. A sample of 19 994 Canadian adults (aged ≥18 years) was recruited from established members of the Angus Reid Forum, a public polling organization. The study comprised 2 phases (phase 1 from May 1 to September 30, 2020, and phase 2 from December 1, 2020, to March 31, 2021) that generally corresponded to the first (April 1 to July 31, 2020) and second (October 1, 2020, to March 1, 2021) viral waves. SARS-CoV-2 immunoglobulin G seropositivity (using a chemiluminescence assay) by major geographic and demographic variables and correlation with COVID-19 symptom reporting. Among 19 994 adults who completed the online questionnaire in phase 1, the mean (SD) age was 50.9 (15.4) years, and 10 522 participants (51.9%) were female; 2948 participants (14.5%) had self-identified racial and ethnic minority group status, and 1578 participants (8.2%) were self-identified Indigenous Canadians. Among participants in phase 1, 8967 had DBS testing. In phase 2, 14 621 adults completed online questionnaires, and 7102 of those had DBS testing. Of 19 994 adults who completed the online survey in phase 1, fewer had an educational level of some college or less (4747 individuals [33.1%]) compared with the general population in Canada (45.0%). Survey respondents were otherwise representative of the general population, including in prevalence of known risk factors associated with SARS-CoV-2 infection. The cumulative incidence of SARS-CoV-2 infection among unvaccinated adults increased from 1.9% in phase 1 to 6.5% in phase 2. The seropositivity pattern was demographically and geographically heterogeneous during phase 1 but more homogeneous by phase 2 (with a cumulative incidence ranging from 6.4% to 7.0% in most regions). The exception was the Atlantic region, in which cumulative incidence reached only 3.3% (odds ratio [OR] vs Ontario, 0.46; 95% CI, 0.21-1.02). A total of 47 of 188 adults (25.3%) reporting COVID-19 symptoms during phase 2 were seropositive, and the OR of seropositivity for COVID-19 symptoms was 6.15 (95% CI, 2.02-18.69). In phase 2, 94 of 444 seropositive adults (22.2%) reported having no symptoms. Of 134 seropositive adults in phase 1 who were retested in phase 2, 111 individuals (81.8%) remained seropositive. Participants who had a history of diabetes (OR, 0.58; 95% CI, 0.38-0.90) had lower odds of having detectable antibodies in phase 2. The Action to Beat Coronavirus study found that the incidence of SARS-CoV-2 infection in Canada was modest until March 2021, and this incidence was lower than the levels of population immunity required to substantially reduce transmission of the virus. Ongoing vaccination efforts remain central to reducing viral transmission and mortality. Assessment of future infection-induced and vaccine-induced immunity is practicable through the use of serial online surveys and participant-collected DBS.

Epidemiology of Herpes Simplex Virus Type 2 in Canada, Australia, and New Zealand: Systematic Review, Meta-Analyses, and Meta-Regressions.

This study characterized the epidemiology of herpes simplex virus type 2 (HSV-2) infection in Canada, Australia, and New Zealand. Cochrane and PRISMA guidelines were followed to systematically review, synthesize, and report HSV-2-related data up to January 21, 2021. Meta-analyses and meta-regressions were performed. In Canada, pooled mean seroprevalence was 10.0% (95% confidence interval [CI], 7.8-12.4%) among general populations, 44.5% (95% CI, 20.0-70.5%) among sexually transmitted infection clinic attendees and symptomatic populations, and 60.7% (95% CI, 49.8-71.1%) among human immunodeficiency virus (HIV)-positive individuals and individuals in HIV-discordant couples. In Australia and New Zealand, combined, pooled mean seroprevalence was 15.4% (95% CI, 9.6-22.2%) among general populations, 27.8% (95% CI, 12.0-47.2%) among men who have sex with men, and 37.2% (95% CI, 23.7-51.8%) among sexually transmitted infection clinic attendees and symptomatic populations. Men had 0.64-fold (95% CI, 0.47-0.86) lower seroprevalence compared with women. No evidence was found for a decline in seroprevalence over time. Pooled mean proportion of HSV-2 isolation in laboratory-confirmed genital herpes was 62.1% (95% CI, 53.8-70.1%) in Canada and 71.9% (95% CI, 64.2-78.9%) in Australia and New Zealand. Proportion of HSV-2 isolation in genital herpes declined by 0.98-fold (95% CI, 0.97-0.99) per year. Pooled mean proportion of HSV-2 isolation in genital ulcer disease was 17.4% (95% CI, 4.0-37.1%) in these countries. Over 10% of adults in these countries are infected, with no evidence for declining seroprevalence, unlike other global regions. Over 60% of genital herpes cases are caused by HSV-2 in these countries, yet HSV-2's role is declining by 2% per year.

Integrated Prenatal Care for Women Living With HIV: Primary Care Outcomes in Saskatoon, Saskatchewan

Saskatchewan has the highest rate of new human immunodeficiency virus (HIV) infections in Canada. Of those newly diagnosed, 56% identify as female, 76% identify as Indigenous, and 71% report a history of intravenous drug use. These statistics are strikingly different compared with Canadian data. This brief communication describes prenatal care provided to women living with HIV at an interdisciplinary primary care clinic in Saskatchewan, demonstrating that, despite facing great barriers such as housing insecurity, substance use, and institutionalized racism, women living with HIV can have positive outcomes, including engagement in care and the prevention of perinatal HIV infection.

Correlation between Phenotypic and In Silico Detection of Antimicrobial Resistance in Salmonella enterica in Canada Using Staramr.

Whole genome sequencing (WGS) of Salmonella supports both molecular typing and detection of antimicrobial resistance (AMR). Here, we evaluated the correlation between phenotypic antimicrobial susceptibility testing (AST) and in silico prediction of AMR from WGS in Salmonella enterica (n = 1321) isolated from human infections in Canada. Phenotypic AMR results from broth microdilution testing were used as the gold standard. To facilitate high-throughput prediction of AMR from genome assemblies, we created a tool called Staramr, which incorporates the ResFinder and PointFinder databases and a custom gene-drug key for antibiogram prediction. Overall, there was 99% concordance between phenotypic and genotypic detection of categorical resistance for 14 antimicrobials in 1321 isolates (18,305 of 18,494 results in agreement). We observed an average sensitivity of 91.2% (range 80.5–100%), a specificity of 99.7% (98.6–100%), a positive predictive value of 95.4% (68.2–100%), and a negative predictive value of 99.1% (95.6–100%). The positive predictive value of gentamicin was 68%, due to seven isolates that carried aac(3)-IVa, which conferred MICs just below the breakpoint of resistance. Genetic mechanisms of resistance in these 1321 isolates included 64 unique acquired alleles and mutations in three chromosomal genes. In general, in silico prediction of AMR in Salmonella was reliable compared to the gold standard of broth microdilution. WGS can provide higher-resolution data on the epidemiology of resistance mechanisms and the emergence of new resistance alleles.

Immigrant generational status and the uptake of HIV screening services among heterosexual men of African descent in Canada: Evidence from the weSpeak study

ObjectiveCanada became a preferred destination for many non-European and non-American migrants since the introduction of favorable immigration policies in the late 1960 s. Blackimmigrants from the African and Caribbean regions however are a known vulnerable population to HIV infection in Canada. Even though first-generation immigrants might differ from subsequent generations in terms of culture and beliefs which are important for health outcomes and behaviors, research examining disparities in their use of preventative healthcare is limited. This study aimed to examine generational disparities in the uptake of HIV screening services among a sample of heterosexual Black men in Ontario, Canada. MethodsWe used data from a cross-sectional survey sample (n = 829) that was collected from heterosexual Black men in four Ontarian cities (Toronto, Ottawa, London and Windsor) between March 2018 and February 2019. We used the negative log-log link function of the binomial family to examine the independent relationship between immigration status and the uptake of HIV testing and the cumulative effect of other predictor variables on HIV testing in nested models. ResultsFindings from multivariate analysis show second-generation immigrants were significantly less likely to test for HIV compared with their first-generation immigrant counterparts. After controlling for theoretically relevant variables, the second-generation immigrants were 53% less likely to test for HIV. We further observed that participants with good knowledge of HIV transmission (OR=1.05; p > 0.05) and those who were older were more likely to test for HIV. Those with masculine tendencies (OR=0.98; p > 0.05) and those who reported not having sexual partner were less likely to test (OR=0.57; p > 0.01). Religion emerged as a significant predictor of HIV testing as Christians (OR=1.62; p > 0.05) and other believers (OR=1.59; p > 0.05) were more likely to test for HIV when compared to their Muslim counterparts. ConclusionHIV prevention policies may need not only prioritize first-generation immigrants, but the wellbeing of their descendants as well. This could be achieved by implementing programs that will enhance second-generation immigrants’ use of HIV screening services. Additionally, HIV educational programs would be of relevance and especially so as respondents with good knowledge of HIV transmission consistently demonstrated higher likelihood of testing for their HIV status.

Four genomic clades of Candida auris identified in Canada, 2012–2019

The fungal pathogen Candida auris has caused many hospital outbreaks and is often multidrug resistant. All four major strains of C. auris were identified in Canada from 2012 to 2019. Genomic epidemiology may be useful for identifying and reducing transmission of C. auris within hospitals.

850. Reasons for not Using PrEP and Actions that May Facilitate PrEP Uptake in Ontario and British Columbia, Canada

BackgroundHIV Pre-exposure prophylaxis (PrEP) is an underutilized intervention to prevent HIV infection in Canada. Known barriers to PrEP uptake include lack of awareness, low HIV risk perception, side effects, PrEP not being publicly funded (which is the case in Ontario) and stigma. We aimed to identify barriers to PrEP use and actions that may facilitate PrEP uptake in Ontario and British Columbia.MethodsGay, bisexual and other men who have sex with men 19 years or older living in Ontario and British Columbia, Canada, answered a survey between July 2019 and August 2020. Participants who met Canadian PrEP guideline criteria for PrEP and not already using PrEP indicated which barriers were relevant to them and which actions would make them more likely to start PrEP. We used descriptive statistics and tested differences between Ontario and British Columbia using Chi-square tests for proportions and t-tests or Wilcoxon rank-sum tests for continuous variables. ResultsOf 1527 survey responses, 260 (184 in Ontario and 76 in British Columbia) who were never PrEP users and met criteria for PrEP were included. In Ontario, the most common barriers were affordability (43%) and concern about side effects (42%). In British Columbia, the most common reasons were concern about side effects (41%) and not feeling at high enough risk (36%). In Ontario, the actions that would most likely encourage the respondent to start PrEP were short waiting time (63%), the healthcare provider informing about their HIV risk being higher than perceived (62%) and a written step-by-step guide (60%). In British Columbia, the actions that would most likely encourage the respondent to start PrEP were short waiting time (68%), people speaking publicly about PrEP (68%) and their healthcare provider counselling about: their HIV risk being higher than perceived (64%), side effects of PrEP (64%) and about how PrEP works (62%).Table. Top reasons for not using PrEP and top actions that might influence the decision to start PrEP stratified by province. (n= 184 in Ontario, n= 76 in British Columbia). ConclusionConcern about side effects and not feeling at high enough risk were common barriers. Short waiting times may increase PrEP uptake. In Ontario, the findings suggested lack of affordability. In British Columbia, actions involving healthcare providers were valued.Disclosures Kevin Woodward, MD FRCPC, Gilead (Independent Contractor) Darrell Tan, MD PhD, Abbvie (Grant/Research Support)Gilead (Grant/Research Support)GlaxoSmithKline (Scientific Research Study Investigator)ViiV Healthcare (Grant/Research Support)

483. Disease Severity and Clinical Manifestations of SARS-CoV-2 Infection Among Infants Over the First Year of the Pandemic in Canada

BackgroundThere is limited data on outcomes of SARS-CoV-2 infection among infants (< 1 year of age). In the absence of any approved vaccines for infants, understanding the risk factors for hospitalization and severe disease from COVID-19 in this age group will help inform clinical management and targeted public health interventions. The objective of this study was to describe the clinical manifestations, disease severity, and risk factors for hospitalization among infants with SARS-CoV-2 infection in Canada. MethodsThis is a nationwide prospective observational study using the infrastructure of the Canadian Paediatric Surveillance Program. All cases of infants aged < 1 year of age with microbiologically confirmed SARS-CoV-2 infection were reported from April 8th 2020 to May 11th 2021, and classified by disease severity, and primary cause of hospitalization. Logistic regression was performed to identify risk factors for hospitalization and severe disease.ResultsA total of 393 cases were reported, including 229 (58.3%) non-hospitalized and 164 (41.7%) hospitalized infants. The most common symptoms included fever (63.4%), runny nose (45.0%), cough (35.1%) and decreased oral intake (24.9%). Significant risk factors for hospitalization included younger age and presence of comorbid conditions (excluding prematurity), as shown in the Table. Among hospitalized infants, 108 (65.9%) were admitted because of COVID-19-related illness, and 52 (31.7%) were admitted for reasons other than COVID-19. A total of 31 (7.9%) infants developed severe or critical disease. Risk factors for severe disease included prematurity and younger age (Table). ConclusionWe describe one of the largest cohort of infants with SARS-CoV-2 infection. Severe disease in this age group is uncommon, with younger age and prematurity being significant risk factors for severe COVID-19. Disclosures Pierre-Philippe Piché-Renaud, MD, Pfizer Global Medical Grants (Competitive grant program) (Research Grant or Support, Investigator-led project on the impact of COVID-19 on routine childhood immunizations) Olivier Drouin, MDCM MsC MPH, Covis Pharma (Research Grant or Support) Shaun Morris, MD, MPH, DTM&H, FRCPC, FAAP, GSK (Speaker’s Bureau)Pfizer (Advisor or Review Panel member)Pfizer (Grant/Research Support)

ECHO+: Improving access to hepatitis C care within Indigenous communities in Alberta, Canada.

Indigenous populations experience higher rates of hepatitis C virus (HCV) infections in Canada. The Extension for Community Health Outcomes+ (ECHO+) telehealth model was implemented in Alberta to support HCV screening and treatment, using Zoom technology to support Indigenous patient access to specialist care closer to home. Our goal was to expand this program to more Indigenous communities in Alberta, using various Indigenous-led or co-designed methods. The ECHO+ team implemented a Two-Eyed Seeing framework, incorporating Indigenous wholistic approaches alongside Western treatment. This approach works with principles of respect, reciprocity, and relationality. The ECHO+ team identified Indigenous-specific challenges, including access to liver specialist care, HCV awareness, stigma, barriers to screening and lack of culturally relevant approaches. Access to HCV care via this program significantly increased HCV antiviral use in the past 5 years. Key lessons learned include Indigenous-led relationship building and development of project outputs in response to community needs influences impact and increases relevant changes increasing access to HCV care. Implementation of ECHO+ was carried out through biweekly telehealth sessions, problem solving in partnership with Indigenous communities, increased HCV awareness, and flexibility resulting from the impacts of COVID-19. Improving Indigenous patient lives and reducing inequity requires supporting local primary health care providers to create and sustain integrated HCV prevention, diagnosis, treatment, and support services within a culturally safe and reciprocal model. ECHO+ uses telehealth and culturally appropriate methodology and interventions alongside multiple stakeholder collaborations to improve health outcomes for HCV.

Characteristics of children admitted to hospital with acute SARS-CoV-2 infection in Canada in 2020.

Background:Risk factors for severe outcomes of SARS-CoV-2 infection are not well established in children. We sought to describe pediatric hospital admissions associated with SARS-CoV-2 infection in Canada and identify risk factors for more severe disease.Methods:We conducted a national prospective study using the infrastructure of the Canadian Paediatric Surveillance Program (CPSP). Cases involving children who were admitted to hospital with microbiologically confirmed SARS-CoV-2 infection were reported from Apr. 8 to Dec. 31 2020, through weekly online questionnaires distributed to the CPSP network of more than 2800 pediatricians. We categorized hospital admissions as related to COVID-19, incidental, or for social or infection control reasons and determined risk factors for disease severity in hospital.Results:Among 264 hospital admissions involving children with SARS-CoV-2 infection during the 9-month study period, 150 (56.8%) admissions were related to COVID-19 and 100 (37.9%) were incidental infections (admissions for other reasons and found to be positive for SARS-CoV-2 on screening). Infants (37.3%) and adolescents (29.6%) represented most cases. Among hospital admissions related to COVID-19, 52 (34.7%) had critical disease, 42 (28.0%) of whom required any form of respiratory or hemodynamic support, and 59 (39.3%) had at least 1 underlying comorbidity. Children with obesity, chronic neurologic conditions or chronic lung disease other than asthma were more likely to have severe or critical COVID-19.Interpretation:Among children who were admitted to hospital with SARS-CoV-2 infection in Canada during the early COVID-19 pandemic period, incidental SARS-CoV-2 infection was common. In children admitted with acute COVID-19, obesity and neurologic and respiratory comorbidities were associated with more severe disease.

In vitro susceptibility of common bacterial pathogens causing respiratory tract infections in Canada to lefamulin, a new pleuromutilin.

Community-acquired pneumonia (CAP) is a significant global health concern. Pathogens causing CAP demonstrate increasing resistance to commonly prescribed empiric treatments. Resistance in Streptococcus pneumoniae, the most prevalent bacterial cause of CAP, has been increasing worldwide, highlighting the need for improved antibacterial agents. Lefamulin, a novel pleuromutilin, is a recently approved therapeutic agent highly active against many lower respiratory tract pathogens. However, to date minimal data are available to describe the in vitro activity of lefamulin against bacterial isolates associated with CAP. Common bacterial causes of CAP obtained from both lower respiratory and blood specimen isolates cultured by hospital laboratories across Canada were submitted to the annual CANWARD study's coordinating laboratory in Winnipeg, Canada, from January 2015 to October 2018. A total of 876 bacterial isolates were tested against lefamulin and comparator agents using the Clinical and Laboratory Standards Institute (CLSI) reference broth microdilution method, and minimum inhibitory concentrations (MICs) were interpreted using accepted breakpoints. All S. pneumoniae isolates tested from both respiratory (n=315) and blood specimens (n=167) were susceptible to lefamulin (MIC ≤0.5 μg/mL), including isolates resistant to penicillins, clarithromycin, doxycycline, and trimethoprim-sulfamethoxazole. Lefamulin also inhibited 99.0% of Haemophilus influenzae isolates (regardless of β-lactamase production) (99 specimens; MIC ≤2 μg/mL) and 95.7% of methicillin-susceptible Staphylococcus aureus (MSSA) (MIC ≤0.25 μg/mL; 70 specimens) at their susceptible breakpoints. Conclusions: Lefamulin demonstrated potent in vitro activity against all respiratory isolates tested and may represent a significant advancement in empiric treatment options for CAP.

Draft Genome Sequences of 113 Escherichia coli Strains Isolated from Intramammary Infections in Dairy Cattle.

Escherichia coli is one of the most common etiological agents responsible for clinical bovine mastitis. Here, we report the draft genome sequences and annotations of 113 E. coli strains that were isolated from Holstein cows with intramammary infections in Canada.

Newcomer knowledge, attitudes, and beliefs about human papillomavirus (HPV) vaccination

BackgroundHuman Papillomavirus (HPV) is the most common sexually transmitted infection in Canada and around the world. Vaccination is an effective prevention strategy, but uptake is low, especially among newcomers to Canada. We sought to understand newcomers’ knowledge, attitudes, and beliefs (KAB) on HPV and HPV vaccination and their role in HPV vaccine acceptance.MethodsNewcomers were defined as individuals born outside Canada, (i.e., individuals born in a different country, the majority of whom are immigrants or refugees, but also includes students and undocumented migrants). Eligible participants were newcomers, aged 16 or older and who could read or write in English, French or Arabic. Surveys were administered in two community health centres in Ottawa, Canada that primarily engage with newcomer populations. Follow-up interviews were conducted either at the community health centre or over the phone, depending on participants’ preferences.ResultsFifty participants completed the survey, the majority of whom were women (74%) and spoke Arabic as their first language (54%). Seven participants completed supplemental interviews to complement their survey responses. The majority (70%) of participants had not previously heard of HPV. Less than half (46%) knew that the vaccine is effective in preventing certain types of cancer; nearly 40% incorrectly believed the vaccine could cure HPV. Qualitative interviews supported the survey findings.ConclusionsDespite a lack of HPV knowledge due to cultural and language barriers, there is still a strong desire among newcomers to receive the vaccine, especially when accompanied by a physician recommendation. Cultural and language-appropriate resources are needed to help newcomers make informed vaccination decisions and promote HPV vaccine uptake.

SARS-CoV-2 Seroprevalence During the First and Second Pandemic Waves in Canada

Background: The prevalence of infection in Canada’s COVID-19 viral waves, the predictors of infection, and the durability of antibody responses to infection remain undocumented.Methods: We organized serial online surveys of a representative group of Canadian adults about their COVID experience in the first (n=19 994; April-July 2020) and second viral wave (n=14 621; October 2020-March 2021). We paired these with IgG analysis of SARS-CoV-2 seroprevalence in self-collected dried blood spots after the first (n=8967) and second (n=7102) waves.Findings: Canada’s cumulative seroprevalence of SARS-CoV-2 among unvaccinated adults rose from ~2% after the first wave to 7% after the second. The seropositivity pattern was heterogeneous demographically and geographically during the first wave, but more homogeneous by the second (except in the four Atlantic Provinces, cumulative seroprevalence ~3%). Seroprevalence among visible minorities rose sharply from about 2% to >8% from the first to second wave. About a quarter of those reporting COVID symptoms during the second wave were seropositive, and in both waves the odds ratio (OR) of seropositivity for COVID symptoms exceeded six. About one-fifth of seropositives reported no symptoms. Of 134 seropositive adults in the first wave who were retested after the second, 83% (111) remained seropositive at least seven months later. Current smokers and people with a history of diabetes had lower ORs of infection. We calculated the absolute numbers of seropositive adults nationwide, which nearly quadrupled from 0.57 million to 1.90 million, with the largest increases among older adults. Infection fatality rates fell from 3.7 to 2.6/1000 infections, most notably at older ages.Interpretation: Canada’s COVID pandemic grew substantially between the first and second viral waves. Home-based DBS collection offers a practicable way to document evolving demographic and geographic patterns and to assess the levels and durability of population immunity, including from SARS-CoV-2 vaccination.Funding: Pfizer Global Medical, Unity Health Foundation, and the Canadian COVID-19 Immunity Task Force. Declaration of Interest: None to declare. Ethical Approval: The Ab-C study was approved by the Unity Health Toronto Ethics Review Board.

299. Paediatric Collaborative Network on Infections in Canada (PICNIC) Study of the Current Landscape of Gram Negative Bacteremias

BackgroundAntimicrobial resistance is a public health threat, invasive infection from multi-drug resistant gram-negative (MDRGN) pathogens is associated with significant morbidity and mortality. The incidence of MDRGN bacteremia in Canada is rising, and pediatric data is limited.MethodsThis retrospective chart review of paediatric patients with gram negative bacteremia in a multicenter PICNIC database (n=7 centers) from 2013 to 2017. MDRGN was defined as enterobacteriaceae that were resistant to third generation cephalosporins (including ESBL, CPE). Ethics approval was obtained at all sites, and data was entered into a secure REDCAP database, descriptive statistics are described herein.ResultsOf the 676 bacteremia patients in the database, 214 (31.7%) were gram negative pathogens. E. coli was the most frequent pathogen (59.8%, of which 22 of 128 were MDR), followed by Klebsiella (31.8%, of which 9 of 68 were MDR). Of the 31 MDRGNs, 19 were ESBL, 1 was a CPE, and 11 were nonspecific mechanisms of resistance. There were no multidrug resistant Pseudomonas, Stenotrophomonas, or Acinetobacter. The majority of patient were less than 3 months of age (59.3%) and were male (58.8%). The majority had an underlying comorbid condition; hematoncologic diagnosis accounting for 14.5%. Length of stay varied from 1 to 742 days (mean 72, standard deviation 88). 11% required admission to ICU, 10% required removal of a intravascular catheter, 7% required a change in ventilation status, 2% requiring procedural source control, and there was an 8% mortality rate. Treatment duration greater than 14 days occurred in 123 patients (61% of patients). ConclusionThis preliminary analysis of a multicenter review of pediatric gram negative bacteremias demonstrates a higher risk in neonates with comorbid conditions. A surprisingly prolonged treatment duration of greater than 14 days occurred in the majority of patients. Further analysis to assess factors associated with prolonged treatment durations, MDR infection, and complications is required. Gram negative bacteremia remains a significant cause of morbidity and mortality in pediatric patients.Disclosures All Authors: No reported disclosures

Advancements in Characterizing Tenacibaculum Infections in Canada.

Tenacibaculum is a genus of gram negative, marine, filamentous bacteria, associated with the presence of disease (tenacibaculosis) at aquaculture sites worldwide; however, infections induced by this genus are poorly characterized. Documents regarding the genus Tenacibaculum and close relatives were compiled for a literature review, concentrating on ecology, identification, and impacts of potentially pathogenic species, with a focus on Atlantic salmon in Canada. Tenacibaculum species likely have a cosmopolitan distribution, but local distributions around aquaculture sites are unknown. Eight species of Tenacibaculum are currently believed to be related to numerous mortality events of fishes and few mortality events in bivalves. The clinical signs in fishes often include epidermal ulcers, atypical behaviors, and mortality. Clinical signs in bivalves often include gross ulcers and discoloration of tissues. The observed disease may differ based on the host, isolate, transmission route, and local environmental conditions. Species-specific identification techniques are limited; high sequence similarities using conventional genes (16S rDNA) indicate that new genes should be investigated. Annotating full genomes, next-generation sequencing, multilocus sequence analysis/typing (MLSA/MLST), matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF), and fatty acid methylesters (FAME) profiles could be further explored for identification purposes. However, each aforementioned technique has disadvantages. Since tenacibaculosis has been observed world-wide in fishes and other eukaryotes, and the disease has substantial economic impacts, continued research is needed.