Povidone Iodine vs Chlorhexidine Gluconate in Alcohol for Preoperative Skin Antisepsis: A Randomized Clinical Trial.

Importance: Preoperative skin antisepsis is an established procedure to prevent surgical site infections (SSIs). The choice of antiseptic agent, povidone iodine or chlorhexidine gluconate, remains debated. Objective: To determine whether povidone iodine in alcohol is noninferior to chlorhexidine gluconate in alcohol to prevent SSIs after cardiac or abdominal surgery. Design, Setting, and Participants: Multicenter, cluster-randomized, investigator-masked, crossover, noninferiority trial; 4403 patients undergoing cardiac or abdominal surgery in 3 tertiary care hospitals in Switzerland between September 2018 and March 2020 were assessed and 3360 patients were enrolled (cardiac, n = 2187 [65%]; abdominal, n = 1173 [35%]). The last follow-up was on July 1, 2020. Interventions: Over 18 consecutive months, study sites were randomly assigned each month to either use povidone iodine or chlorhexidine gluconate, each formulated in alcohol. Disinfectants and skin application processes were standardized and followed published protocols. Main Outcomes and Measures: Primary outcome was SSI within 30 days after abdominal surgery and within 1 year after cardiac surgery, using definitions from the US Centers for Disease Control and Prevention's National Healthcare Safety Network. A noninferiority margin of 2.5% was used. Secondary outcomes included SSIs stratified by depth of infection and type of surgery. Results: A total of 1598 patients (26 cluster periods) were randomly assigned to receive povidone iodine vs 1762 patients (26 cluster periods) to chlorhexidine gluconate. Mean (SD) age of patients was 65.0 years (39.0-79.0) in the povidone iodine group and 65.0 years (41.0-78.0) in the chlorhexidine gluconate group. Patients were 32.7% and 33.9% female in the povidone iodine and chlorhexidine gluconate groups, respectively. SSIs were identified in 80 patients (5.1%) in the povidone iodine group vs 97 (5.5%) in the chlorhexidine gluconate group, a difference of 0.4% (95% CI, -1.1% to 2.0%) with the lower limit of the CI not exceeding the predefined noninferiority margin of -2.5%; results were similar when corrected for clustering. The unadjusted relative risk for povidone iodine vs chlorhexidine gluconate was 0.92 (95% CI, 0.69-1.23). Nonsignificant differences were observed following stratification by type of surgical procedure. In cardiac surgery, SSIs were present in 4.2% of patients with povidone iodine vs 3.3% with chlorhexidine gluconate (relative risk, 1.26 [95% CI, 0.82-1.94]); in abdominal surgery, SSIs were present in 6.8% with povidone iodine vs 9.9% with chlorhexidine gluconate (relative risk, 0.69 [95% CI, 0.46-1.02]). Conclusions and Relevance: Povidone iodine in alcohol as preoperative skin antisepsis was noninferior to chlorhexidine gluconate in alcohol in preventing SSIs after cardiac or abdominal surgery. Trial Registration: ClinicalTrials.gov Identifier: NCT03685604.

Decreasing Incidence and Determinants of Bacterial Pneumonia in People With HIV: The Swiss HIV Cohort Study.

BACKGROUND: Bacterial pneumonia is a leading reason for hospitalization among people with HIV (PWH); however, evidence regarding its drivers in the era of potent antiretroviral therapy is limited. METHODS: We assessed risk factors for bacterial pneumonia in the Swiss HIV Cohort Study using marginal models. We further assessed the relationship between risk factors and changes in bacterial pneumonia incidence using mediation analysis. RESULTS: We included 12927 PWH with follow-ups between 2008 and 2018. These patients had 985 bacterial pneumonia events during a follow-up of 100779 person-years. Bacterial pneumonia incidence significantly decreased from 13.2 cases/1000 person-years in 2008 to 6.8 cases/1000 person-years in 2018. Older age, lower education level, intravenous drug use, smoking, lower CD4-cell count, higher HIV load, and prior pneumonia were significantly associated with higher bacterial pneumonia incidence. Notably, CD4 cell counts 350-499 cells/µL were significantly associated with an increased risk compared to CD4 ≥ 500 cells/µL (adjusted hazard ratio, 1.39; 95% confidence interval, 1.01-1.89). Decreasing incidence over the last decade can be explained by increased CD4-cell counts and viral suppression and decreased smoking frequency. CONCLUSIONS: Improvements in cascade of care of HIV and decrease in smoking may have mediated a substantial decrease in bacterial pneumonia incidence.

Identifying Contact Risks for SARS-CoV-2 Transmission to Healthcare Workers during Outbreak on COVID-19 Ward.

We assessed the risk for different exposures to SARS-CoV-2 during a COVID-19 outbreak among healthcare workers on a hospital ward in late 2020. We found working with isolated COVID-19 patients did not increase the risk of COVID-19 among workers, but working shifts with presymptomatic healthcare coworkers did.

Nosocomial COVID-19 Incidence and Secondary Attack Rates among Patients of Tertiary Care Center, Zurich, Switzerland.

Of 1,118 patients with COVID-19 at a university hospital in Switzerland during October 2020-June 2021, we found 83 (7.4%) had probable or definite healthcare-associated COVID-19. After in-hospital exposure, we estimated secondary attack rate at 23.3%. Transmission was associated with longer contact times and with lower cycle threshold values among index patients.

Systemic and mucosal antibody responses specific to SARS-CoV-2 during mild versus severe COVID-19.

BACKGROUND: Whereas severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific antibody tests are increasingly being used to estimate the prevalence of SARS-CoV-2 infection, the determinants of these antibody responses remain unclear. OBJECTIVES: Our aim was to evaluate systemic and mucosal antibody responses toward SARS-CoV-2 in mild versus severe coronavirus disease 2019 (COVID-19) cases. METHODS: Using immunoassays specific for SARS-CoV-2 spike proteins, we determined SARS-CoV-2-specific IgA and IgG in sera and mucosal fluids of 2 cohorts, including SARS-CoV-2 PCR-positive patients (n = 64) and PCR-positive and PCR-negtive health care workers (n = 109). RESULTS: SARS-CoV-2-specific serum IgA titers in patients with mild COVID-19 were often transiently positive, whereas serum IgG titers remained negative or became positive 12 to 14 days after symptom onset. Conversely, patients with severe COVID-19 showed a highly significant increase of SARS-CoV-2-specific serum IgA and IgG titers after symptom onset. Very high titers of SARS-CoV-2-specific serum IgA were correlated with severe acute respiratory distress syndrome. Interestingly, some health care workers with negative SARS-CoV-2-specific serum antibody titers showed SARS-CoV-2-specific IgA in mucosal fluids with virus-neutralizing capacity in some cases. SARS-CoV-2-specific IgA titers in nasal fluids were inversely correlated with age. CONCLUSIONS: Systemic antibody production against SARS-CoV-2 develops mainly in patients with severe COVID-19, with very high IgA titers seen in patients with severe acute respiratory distress syndrome, whereas mild disease may be associated with transient production of SARS-CoV-2-specific antibodies but may stimulate mucosal SARS-CoV-2-specific IgA secretion.

Universal Admission Screening for SARS-CoV-2 Infections among Hospitalized Patients, Switzerland, 2020.

Switzerland began a national lockdown on March 16, 2020, in response to the rapid spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We assessed the prevalence of SARS-CoV-2 infection among patients admitted to 4 hospitals in the canton of Zurich, Switzerland, in April 2020. These 4 acute care hospitals screened 2,807 patients, including 2,278 (81.2%) who did not have symptoms of coronavirus disease (COVID-19). Overall, 529 (18.8%) persons had >1 symptom of COVID-19, of whom 60 (11.3%) tested positive for SARS-CoV-2. Eight asymptomatic persons (0.4%) also tested positive for SARS-CoV-2. Our findings indicate that screening on the basis of COVID-19 symptoms, regardless of clinical suspicion, can identify most SARS-CoV-2-positive persons in a low-prevalence setting.

Implementation and evaluation of a care bundle for prevention of non-ventilator-associated hospital-acquired pneumonia (nvHAP) - a mixed-methods study protocol for a hybrid type 2 effectiveness-implementation trial.

BACKGROUND: Hospital acquired pneumonia (HAP) is divided in two distinct groups, ventilator-associated pneumonia (VAP) and non-ventilator-associated HAP (nvHAP). Although nvHAP occurs more frequently than VAP and results in similar mortality and costs, prevention guidelines and prevention focus almost exclusively on VAP. Scientific evidence about nvHAP prevention and its implementation is scarce. Therefore, we designed a mixed-methods hybrid type 2 effectiveness-implementation study to investigate both the effectiveness and implementation of a newly developed nvHAP prevention bundle. METHODS: This single-centre project at the 950-bed University Hospital Zurich (UHZ) will engage the wards of nine departments with substantial nvHAP rates. The nvHAP bundle consists of five primary prevention measures: 1) oral care, 2) prevention of dysphagia-related aspiration, 3) mobilization, 4) stopping unnecessary proton pump inhibitors, and, 5) respiratory therapy. Implementation includes the engagement of department-level implementation teams, who sustain the 'core' intervention components of education, training, and environmental restructuring and tailor the implementation strategy to local needs. Both effectiveness and implementation outcomes will be assessed using mixed-methods. As a primary outcome, nvHAP incidence rates will be analysed by Poisson regression models to compare incidence rates before, during, and after the implementation phases (on the hospital and department level). Additionally, the association between process indicators and nvHAP incidence rates will be analysed using longitudinal Poisson regression models. A longitudinal, qualitative study and formative evaluation based on interviews, focus groups, and observations identifies supporting or hindering factors for implementation success in participating departments dynamically over time. This accumulating implementation experience will be constantly fed back to the implementation teams and thus, represents an active implementation element. DISCUSSION: This comprehensive hybrid mixed-methods study is designed to both, measure the effectiveness of a new nvHAP prevention bundle and multifaceted implementation strategy, while also providing insights into how and why it worked or failed. The results of this study may contribute substantially to advancing knowledge and patient safety in the area of a rediscovered healthcare-associated infection - nvHAP. TRIAL REGISTRATION: ClinicalTrials.gov : NCT03361085 . Registered December 2017.

Immunodeficiency and the risk of cervical intraepithelial neoplasia 2/3 and cervical cancer: A nested case-control study in the Swiss HIV cohort study.

HIV-infected women are at increased risk of cervical intraepithelial neoplasia (CIN) and invasive cervical cancer (ICC), but it has been difficult to disentangle the influences of heavy exposure to HPV infection, inadequate screening and immunodeficiency. A case-control study including 364 CIN2/3 and 20 ICC cases matched to 1,147 controls was nested in the Swiss HIV Cohort Study (1985-2013). CIN2/3 risk was significantly associated with low CD4+ cell counts, whether measured as nadir [odds ratio (OR) per 100-cell/µL decrease = 1.15, 95% CI: 1.08, 1.22], or at CIN2/3 diagnosis (1.10, 95% CI: 1.04, 1.16). An association was evident even for nadir CD4+ 200-349 versus ≥350 cells/µL (OR = 1.57, 95% CI: 1.09, 2.25). After adjustment for nadir CD4+, a protective effect of >2-year cART use was seen against CIN2/3 (OR versus never cART use = 0.64, 95% CI: 0.42, 0.98). Despite low study power, similar associations were seen for ICC, notably with nadir CD4+ (OR for 50 vs. >350 cells/µL= 11.10, 95% CI: 1.24, 100). HPV16-L1 antibodies were significantly associated with CIN2/3, but HPV16-E6 antibodies were nearly exclusively detected in ICC. In conclusion, worsening immunodeficiency, even at only moderately decreased CD4+ cell counts, is a significant risk factor for CIN2/3 and cervical cancer.

Automated surveillance of non-ventilator-associated hospital-acquired pneumonia (nvHAP): a systematic literature review.

BACKGROUND: Hospital-acquired pneumonia (HAP) and its specific subset, non-ventilator hospital-acquired pneumonia (nvHAP) are significant contributors to patient morbidity and mortality. Automated surveillance systems for these healthcare-associated infections have emerged as a potentially beneficial replacement for manual surveillance. This systematic review aims to synthesise the existing literature on the characteristics and performance of automated nvHAP and HAP surveillance systems. METHODS: We conducted a systematic search of publications describing automated surveillance of nvHAP and HAP. Our inclusion criteria covered articles that described fully and semi-automated systems without limitations on patient demographics or healthcare settings. We detailed the algorithms in each study and reported the performance characteristics of automated systems that were validated against specific reference methods. Two published metrics were employed to assess the quality of the included studies. RESULTS: Our review identified 12 eligible studies that collectively describe 24 distinct candidate definitions, 23 for fully automated systems and one for a semi-automated system. These systems were employed exclusively in high-income countries and the majority were published after 2018. The algorithms commonly included radiology, leukocyte counts, temperature, antibiotic administration, and microbiology results. Validated surveillance systems' performance varied, with sensitivities for fully automated systems ranging from 40 to 99%, specificities from 58 and 98%, and positive predictive values from 8 to 71%. Validation was often carried out on small, pre-selected patient populations. CONCLUSIONS: Recent years have seen a steep increase in publications on automated surveillance systems for nvHAP and HAP, which increase efficiency and reduce manual workload. However, the performance of fully automated surveillance remains moderate when compared to manual surveillance. The considerable heterogeneity in candidate surveillance definitions and reference standards, as well as validation on small or pre-selected samples, limits the generalisability of the findings. Further research, involving larger and broader patient populations is required to better understand the performance and applicability of automated nvHAP surveillance.

Adverse Outcomes of Patients with Non-Ventilator-Associated Hospital-Acquired Pneumonia (nvHAP)-A Single Centre Cohort Study.

Non-ventilator associated hospital-acquired pneumonia (nvHAP) is a common nosocomial infection, but little is known about the outcomes of patients with nvHAP and the risk factors for adverse outcomes. In this retrospective study conducted in a Swiss tertiary care centre, adverse outcomes like in-hospital mortality, intensive care unit (ICU) admission, and mechanical ventilation, both all-cause and nvHAP-associated, were investigated. Of 244 patients with nvHAP, 72 (30%) died, 35 (14%) deaths were attributed to nvHAP. While 36 (15%) patients acquired nvHAP on the ICU, another 173 patients were eligible for ICU-transferral, and 76 (43.9%) needed ICU-admission. Of all patients hospitalized on the ICU 58 (51.8%) needed intubation due to nvHAP. Multivariable logistic regression analysis identified lower body mass index (OR per unit increase: 0.90, 95%CI: 0.82-0.98) and lower haemoglobin on admission (OR per unit in g/l increase: 0.98, 95%CI: 0.97-1.00) as patient specific factors independently associated with nvHAP-associated mortality. Given the frequency of nvHAP adverse outcomes, hospitals should evaluate increasing nvHAP prevention efforts, especially for patients at high risk for nvHAP mortality. To what extent pneumonia prevention interventions do lower nvHAP mortality in these patients is still to be evaluated.

Influence of clinical breakpoint changes from CLSI 2009 to EUCAST 2011 antimicrobial susceptibility testing guidelines on multidrug resistance rates of Gram-negative rods.

Multidrug resistance (MDR) rates of Gram-negative rods were analyzed comparing CLSI 2009 and EUCAST 2011 antibiotic susceptibility testing guidelines. After EUCAST 2011 was applied, the MDR rates increased for Klebsiella pneumoniae (2.2%), Enterobacter cloacae (1.1%), Pseudomonas aeruginosa (0.7%), and Escherichia coli (0.4%). A total of 24% of Enterobacteriaceae MDR isolates and 12% of P. aeruginosa MDR isolates were categorized as MDR due to breakpoint changes.

Identifying patients at high risk for multidrug-resistant organisms after hospitalization abroad.

OBJECTIVES: We quantified the percentage of multidrug-resistant organism (MDRO) carriers among repatriated patients. We identified factors associated with MDRO carriage, and we evaluated the yield of MDRO detection per screened body site. DESIGN: Retrospective cohort study. SETTING: A tertiary-care center in Switzerland. PATIENTS: Adult patients after a stay in a healthcare institution abroad. METHODS: Patients were screened for MDRO carriage. Standard sites, including nose and throat, groins, and (since mid-2018) rectum, and risk-based sites (wounds, urine, tracheal secretion) were sampled. MDROs were defined as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant Enterococcus (VRE), extended-spectrum ß-lactamase (ESBL)- and carbapenemase-producing Enterobacterales (CPE), multidrug-resistant (MDR) Enterobacterales, and MDR nonfermenting gram-negative rods. Risk factors for MDRO carriage were assessed using multivariate logistic regression. RESULTS: Between May 2017 and April 2019, 438 patients were screened and 107 (24.4%) tested positive for an MDRO, predominantly ESBL-producing and MDR Enterobacterales. Risk factors for MDRO colonization were the length of stay in hospital abroad, antibiotic treatment with 'Watch' and 'Reserve' antibiotics, and region of hospitalization abroad. Rectal swabs had the highest yield for detecting patients with MDR intestinal bacteria, but nose/throat and groins, or wound samples were more sensitive for MRSA or nonfermenting gram-negative organisms, respectively. CONCLUSIONS: We identified risk factors for MDRO carriage and body sites with the highest yield for a specific MDRO, which might help to target screening and isolation and reduce screening costs.

Parallel dynamics in the yield of universal SARS-CoV-2 admission screening and population incidence.

The majority of SARS-CoV-2 transmissions originates from either asymptomatic or presymptomatic individuals. To prevent unnoticed introduction of SARS-CoV-2, many hospitals have implemented universal admission screening during the COVID-19 pandemic. The present study aimed to investigate associations between results of an universal SARS-CoV-2 admission screening and public SARS-CoV-2 incidence. Over a study period of 44 weeks, all patients admitted to a large tertiary care hospital were tested for SARS-CoV-2 by polymerase chain reaction. SARS-CoV-2 positive patients were retrospectively categorized as symptomatic or asymptomatic at admission. Cantonal data were used to calculate weekly incidence rates per 100,000 inhabitants. We used regression models for count data to assess the association of the weekly cantonal incidence rate and the proportion of positive SARS-CoV-2 tests in the canton with (a) the proportion of SARS-CoV-2 positive individuals and (b) the proportion of asymptomatic SARS-CoV-2 infected individuals identified in universal admission screening, respectively. In a 44-week period, a total of 21,508 admission screenings were performed. SARS-CoV-2 PCR was positive in 643 (3.0%) individuals. In 97 (15.0%) individuals, the positive PCR reflected residual viral replication after recent COVID-19, 469 (72.9%) individuals had COVID-19 symptoms and 77 (12.0%) SARS-CoV-2 positive individuals were asymptomatic. Cantonal incidence correlated with the proportion of SARS-CoV-2 positive individuals [rate ratio (RR): 2.03 per 100 point increase of weekly incidence rate, 95%CI 1.92-2.14] and the proportion of asymptomatic SARS-CoV-2 positive individuals (RR: 2.40 per 100 point increase of weekly incidence rate, 95%CI 2.03-2.82). The highest correlation between dynamics in cantonal incidence and results of admission screening was observed at a lag time of one week. Similarly, the proportion of positive SARS-CoV-2 tests in the canton of Zurich correlated with the proportion of SARS-CoV-2 positive individuals (RR: 2.86 per log increase in the proportion of positive SARS-CoV-2 tests in the canton, 95%CI 2.56-3.19) and the proportion of asymptomatic SARS-CoV-2 positive individuals (RR: 6.50 per log increase in the proportion of positive SARS-CoV-2 tests in the canton, 95%CI 3.93-10.75) in admission screening. Around 0.36% of admission screenings were positive in asymptomatic patients. Admission screening results paralleled changes in population incidence with a brief lag.

Prevention of non-ventilator-associated hospital-acquired pneumonia in Switzerland: a type 2 hybrid effectiveness-implementation trial.

BACKGROUND: Non-ventilator-associated hospital-acquired pneumonia (nvHAP) is a frequent, but under-researched infection. We aimed to simultaneously test an nvHAP prevention intervention and a multifaceted implementation strategy. METHODS: In this single-centre, type 2 hybrid effectiveness-implementation study, all patients of nine surgical and medical departments at the University Hospital Zurich, Switzerland, were included and surveyed over three study periods: baseline (14-33 months, depending on department), implementation (2 months), and intervention (3-22 months, depending on department). The five-measure nvHAP prevention bundle consisted of oral care, dysphagia screening and management, mobilisation, discontinuation of non-indicated proton-pump inhibitors, and respiratory therapy. The implementation strategy comprised department-level implementation teams who conducted and locally adapted the core strategies of education, training, and changing infrastructure. Intervention effectiveness on the primary outcome measure of nvHAP incidence rate was quantified using a generalised estimating equation method in a Poisson regression model, with hospital departments as clusters. Implementation success scores and determinants were derived longitudinally through semistructured interviews with health-care workers. This trial is registered with ClinicalTrials.gov (NCT03361085). FINDINGS: Between Jan 1, 2017, and Feb 29, 2020, 451 nvHAP cases occurred during 361 947 patient-days. nvHAP incidence rate was 1·42 (95% CI 1·27-1·58) per 1000 patient-days in the baseline period and 0·90 (95% CI 0·73-1·10) cases per 1000 patient-days in the intervention period. The intervention-to-baseline nvHAP incidence rate ratio, adjusted for department and seasonality, was 0·69 (95% CI 0·52-0·91; p=0·0084). Implementation success scores correlated with lower nvHAP rate ratios (Pearson correlation -0·71, p=0·034). Determinants of implementation success were positive core business alignment, high perceived nvHAP risk, architectural characteristics promoting physical proximity of health-care staff, and favourable key individual traits. INTERPRETATION: The prevention bundle led to a reduction of nvHAP. Knowledge of the determinants of implementation success might help in upscaling nvHAP prevention. FUNDING: Swiss Federal Office of Public Health.

Detection and Molecular Characterization of the SARS-CoV-2 Delta Variant and the Specific Immune Response in Companion Animals in Switzerland.

In human beings, there are five reported variants of concern of severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). However, in contrast to human beings, descriptions of infections of animals with specific variants are still rare. The aim of this study is to systematically investigate SARS-CoV-2 infections in companion animals in close contact with SARS-CoV-2-positive owners ("COVID-19 households") with a focus on the Delta variant. Samples, obtained from companion animals and their owners were analyzed using a real-time reverse transcriptase-polymerase chain reaction (RT-qPCR) and next-generation sequencing (NGS). Animals were also tested for antibodies and neutralizing activity against SARS-CoV-2. Eleven cats and three dogs in nine COVID-19-positive households were RT-qPCR and/or serologically positive for the SARS-CoV-2 Delta variant. For seven animals, the genetic sequence could be determined. The animals were infected by one of the pangolin lineages B.1.617.2, AY.4, AY.43 and AY.129 and between zero and three single-nucleotide polymorphisms (SNPs) were detected between the viral genomes of animals and their owners, indicating within-household transmission between animal and owner and in multi-pet households also between the animals. NGS data identified SNPs that occur at a higher frequency in the viral sequences of companion animals than in viral sequences of humans, as well as SNPs, which were exclusively found in the animals investigated in the current study and not in their owners. In conclusion, our study is the first to describe the SARS-CoV-2 Delta variant transmission to animals in Switzerland and provides the first-ever description of Delta-variant pangolin lineages AY.129 and AY.4 in animals. Our results reinforce the need of a One Health approach in the monitoring of SARS-CoV-2 in animals.

A Risk Factor Analysis of SARS-CoV-2 Infection in Animals in COVID-19-Affected Households.

A higher prevalence of SARS-CoV-2 infections in animals that have close contact with SARS-CoV-2-positive humans ("COVID-19 households") has been demonstrated in several countries. This prospective study aimed to determine the SARS-CoV-2 prevalence in animals from Swiss COVID-19 households and to assess the potential risk factors for infection. The study included 226 companion animals (172 cats, 76.1%; 49 dogs, 21.7%; and 5 other animals, 2.2%) from 122 COVID-19 households with 336 human household members (including 230 SARS-CoV-2-positive people). The animals were tested for viral RNA using an RT-qPCR and/or serologically for antibodies and neutralizing activity. Additionally, surface samples from animal fur and beds underwent an RT-qPCR. A questionnaire about hygiene, animal hygiene, and contact intensity was completed by the household members. A total of 49 of the 226 animals (21.7%) from 31 of the 122 households (25.4%) tested positive/questionably positive for SARS-CoV-2, including 37 of the 172 cats (21.5%) and 12 of the 49 dogs (24.5%). The surface samples tested positive significantly more often in households with SARS-CoV-2-positive animals than in households with SARS-CoV-2-negative animals (p = 0.011). Significantly more animals tested positive in the multivariable analysis for households with minors. For cats, a shorter length of outdoor access and a higher frequency of removing droppings from litterboxes were factors that were significantly associated with higher infection rates. The study emphasizes that the behavior of owners and the living conditions of animals can influence the likelihood of a SARS-CoV-2 infection in companion animals. Therefore, it is crucial to monitor the infection transmission and dynamics in animals, as well as to identify the possible risk factors for animals in infected households.

Estimating incidence and attributable length of stay of healthcare-associated infections-Modeling the Swiss point-prevalence survey.

OBJECTIVES: In 2017, a point-prevalence survey was conducted with 12,931 patients in 96 hospitals across Switzerland as part of the national strategy to prevent healthcare-associated infections (HAIs). We present novel statistical methods to assess incidence proportions of HAI and attributable length-of-stay (LOS) in point-prevalence surveys. METHODS: Follow-up data were collected for a subsample of patients and were used to impute follow-up data for all remaining patients. We used weights to correct length bias in logistic regression and multistate analyses. Methods were also tested in simulation studies. RESULTS: The estimated incidence proportion of HAIs during hospital stay and not present at admission was 2.3% (95% confidence intervals [CI], 2.1-2.6), the most common type being lower respiratory tract infections (0.8%; 95% CI, 0.6-1.0). Incidence proportion was highest in patients with a rapidly fatal McCabe score (7.8%; 95% CI, 5.7-10.4). The attributable LOS for all HAI was 6.4 days (95% CI, 5.6-7.3) and highest for surgical site infections (7.1 days, 95% CI, 5.2-9.0). It was longest in the age group of 18-44 years (9.0 days; 95% CI, 5.4-12.6). Risk-factor analysis revealed that McCabe score had no effect on the discharge hazard after infection (hazard ratio [HR], 1.21; 95% CI, 0.89-1.63). Instead, it only influenced the infection hazard (HR, 1.84; 95% CI, 1.39-2.43) and the discharge hazard prior to infection (HR, 0.73; 95% CI, 0.66-0.82). CONCLUSIONS: In point-prevalence surveys with limited follow-up data, imputation and weighting can be used to estimate incidence proportions and attributable LOS that would otherwise require complete follow-up data.

Documentation of adherence to infection prevention best practice in patient records: a mixed-methods investigation.

BACKGROUND: Healthcare-associated infections remain a preventable cause of patient harm in healthcare. Full documentation of adherence to evidence-based best practices for each patient can support monitoring and promotion of infection prevention measures. Thus, we reviewed the extent, nature, and determinants of the documentation of infection prevention (IP) standards in patients with HAI. METHODS: We reviewed electronic patient records (EMRs) of patients included in four annual point-prevalence studies 2013-2016 who developed a device- or procedure-related HAI (surgical site infection (SSI), catheter-associated urinary tract infection (CAUTI), ventilator-associated infection (VAP), catheter-related bloodstream infection (CRBSI)). We examined the documentation quality of mandatory preventive measures published as institutional IP standards. Additionally, we undertook semi-structured interviews with healthcare providers and a two-step inductive (grounded theory) and deductive (Theory of Planned Behaviour) content analysis. RESULTS: Of overall 2972 surveyed patients, 249 (8.4%) patients developed 272 healthcare-associated infections. Of these, 116 patients met the inclusion criteria, classified as patients with SSI, CAUTI, VAP, CRBSI in 78 (67%), 21 (18%), 10 (9%), 7 (6%), cases, respectively. We found documentation of IP measures in EMRs in 432/1308 (33%) cases. Documentation of execution existed in the study patients' EMRs for SSI, CAUTI, VAP, CRBSI, and overall, in 261/931 (28%), 27/104 (26%), 46/122 (38%), 26/151 (17%), and 360/1308 (28%) cases, respectively, and documentation of non-execution in 67/931 (7%), 2/104 (2%), 0/122 (0%), 3/151 (2%), and 72/1308 (6%) cases, respectively. Healthcare provider attitudes, subjective norms, and perceived behavioural control indicated reluctance to document IP standards. CONCLUSIONS: EMRs rarely included conclusive data about adherence to IP standards. Documentation had to be established indirectly through data captured for other reasons. Mandatory institutional documentation protocols or technically automated documentation may be necessary to address such shortcomings in patient safety documentation.

Modifiable and nonmodifiable risk factors for non-ventilator-associated hospital-acquired pneumonia identified in a retrospective cohort study.

OBJECTIVES: Hospital-acquired pneumonia in nonventilated patients (nvHAP) belongs to the most common healthcare-associated infections. This study aimed to investigate risk factors for nvHAP in patients outside the intensive care unit, focusing on modifiable risk factors. METHODS: All inpatients admitted to an academic teaching hospital in Switzerland between 2017 and 2018 were included. nvHAP was defined according to European Centre for Disease Prevention and Control criteria. Patient days during and after ICU stay were excluded. Candidate risk factors-both constant and time varying-were included in uni- and multivariable Cox proportional hazards models. The decay ratio and the characteristic time of influence of hazard ratios (HRs) was estimated by adopting a linear decay in the Cox model. RESULTS: A total of 66 001 hospitalizations with 314 (0.48%) nvHAP and 471 401 patient days were included. Median age was 57 years (interquartile range: 38 to 71 years) and 32 253 (48.9%) patients were male. Among nonmodifiable risk factors, age (adjusted HR (aHR) 2.66 for age ≥60 years, 95% CI 1.59 to 4.45) and male sex (aHR 1.71, 95% CI 1.34 to 2.18) were independently associated with nvHAP. Time-varying exposures showing strongest independent association with nvHAP were tube feeding (aHR 3.24, 95% CI 2.17 to 4.83), impaired consciousness (aHR 2.32, 95% CI 1.63 to 3.31), and severely impaired activity and mobility (aHR 2.06, 95% CI 1.50 to 2.84). The association with nvHAP decayed within 7.1 to 13.2 days after these exposures ended. DISCUSSION: The risk for nvHAP varies with time, depending on the patient's medical condition and medical interventions. Several risk factors for nvHAP represent potential targets for specific prevention measures.