A Systematic Review and Meta-Analysis of Inpatient Mortality Associated With Nosocomial and Community COVID-19 Exposes the Vulnerability of Immunosuppressed Adults

Vulnerability of hospitalized patients during community disease outbreaks: Lessons from the early COVID-19 pandemic

OBJECTIVES

Hospital-acquired infections (HAIs) during community disease outbreaks threaten vulnerable hospitalized patients. This study compares the outcomes of hospitalized patients who had COVID-19 as either a HAI or a community-acquired infection (CAI).

METHODS

We conducted a retrospective cohort study involving adult patients hospitalized across 39 greater Paris University hospitals between January 27th, 2020, and April 21st, 2021, who tested positive for SARS-CoV-2 PCR during their stay. Patients were classified as CAI if they tested positive within 72hours of admission and HAI if they tested negative within 72hours but later positive. HAI was subclassified as possible (first positive test between days 4-7), probable (days 8-13), or definite (day 14 onward). Patients with probable or definite HAI were matched 1:3 to CAI patients for age, sex, and comorbidities, to compare intensive care unit (ICU) transfer and in-hospital death between both groups.

RESULTS

Of 10,831 patients, 506 (4.7%) were classified as HAI. They were older and had more comorbidities. After matching, the 333 patients with probable or definite HAI were less likely to be transferred to the ICU (hazard ratio [HR] 0.57, 95% CI 0.38-0.85) compared to their 999 CAI controls and had a higher risk for in-hospital death (HR 1.58, 95% CI 1.16-2.14).

CONCLUSION

Patients with COVID-19 as a HAI face a higher risk of death compared to patients hospitalized with COVID-19 acquired in the community and are less likely to be admitted to the ICU. Strict infection control measures are needed during community outbreaks to protect hospitalized patients.

Unraveling relevant cross-waves pattern drifts in patient-hospital risk factors among hospitalized COVID-19 patients using explainable machine learning methods

BACKGROUND

Several studies explored factors related to adverse clinical outcomes among COVID-19 patients but lacked analysis of the impact of the temporal data shifts on the strength of association between different predictors and adverse outcomes. This study aims to evaluate factors related to patients and hospitals in the prediction of in-hospital mortality, need for invasive mechanical ventilation (IMV), and intensive care unit (ICU) transfer throughout the pandemic waves.

METHODS

This multicenter retrospective cohort included COVID-19 patients from 39 hospitals, from March/2020 to August/2022. The pandemic was divided into waves: 10/03/2020-14/11/2020 (first), 15/11/2020-25/12/2021 (second), 26/12/2021-03/08/2022 (third). Patient-related factors included clinical, demographic, and laboratory data, while hospital-related factors covered funding sources, accreditation, academic status, and socioeconomic characteristics. Shapley additive explanation (SHAP) values derived from the predictions of a light gradient-boosting machine (LightGBM) model were used to assess potential risk factors for death, IMV and ICU.

RESULTS

Overall, 16,958 adult patients were included (median age 59 years, 54.7% men). LightGBM achieved competitive effectiveness metrics across all periods. Temporal drifts were observed due to a decrease in various metrics, such as the recall for the positive class [ICU: 0.4211 (wave 1) to 0.1951 (wave 3); IMV: 0.2089 (wave 1) to 0.0438 (wave 3); death: 0.2711 (wave 1) to 0.1175 (wave 3)]. Peripheral arterial oxygen saturation to the fraction of inspired oxygen ratio (SatO2/FiO2) at admission had great predictive capacity for all outcomes, with an optimal cut-off value for death prediction of 227.78. Lymphopenia had its association strength increased over time for all outcomes, optimal threshold for death prediction of 643 × 109/L. Thrombocytopenia was the most important feature in wave 2 (ICU); overall, values below 143,000 × 109/L were more related to death.

CONCLUSION

Data drifts were observed in all scenarios, affecting potential predictive capabilities of explainable machine learning methods. Upon admission, SatO2/FiO2 values, platelet and lymphocyte count were significant predictors of adverse outcomes in COVID-19 patients. Overall, inflammatory response markers were more important than clinical characteristics. Limitations included sample representativeness and confounding factors. Integrating the drift's knowledge into models to improve effectiveness is a challenge, requiring continuous updates and monitoring of performance in real-world applications.

CLINICAL TRIAL NUMBER

Not applicable.

Healthcare-associated COVID-19 infections and mortality

BACKGROUND

It is crucial to quantify the impact of healthcare-associated COVID-19 infections (HAIs) and the resulting mortality to evaluate the requirement for implementing infection prevention and control (IPC) strategies within the healthcare setting.

AIM

To investigate the occurrence of HAIs and associated mortality among hospitalized patients in Norway.

METHODS

A retrospective registry-based study was conducted using national health data in Norway. The study included patients hospitalized between January 1st, 2019, and January 1st, 2023, comparing those with HAI and community-associated COVID-19 infections (CAIs). In all, 54,885 COVID-19 cases were identified, of which 1188 cases met our HAI definition. A total of 742 hospitalized patients with HAI were matched to 2583 hospitalized patients diagnosed with COVID-19 at a later stage by age, sex, length of stay, and hospital unit. HAI was defined as a registered positive SARS-CoV-2 test at least seven days after hospitalization, but before hospital discharge. The primary outcome was 365-day mortality, categorized by HAI or CAI status, quantified by Cox regression and adjusted for age, sex, and diagnoses. Secondary outcomes included mortality variations based on vaccination status and causes of death.

FINDINGS

Mortality rates were consistently higher among HAI patients compared to CAI patients, the difference being highest shortly after infection. Vaccination significantly reduced all-cause and COVID-19 mortality risk.

CONCLUSION

HAI consistently led to higher mortality than CAI, especially during the Omicron phase. Vaccination effectively reduced mortality across both groups. These findings emphasize the importance of IPC measures and vaccination in mitigating the impact of HAIs.

[Understanding vaccination behavior of healthcare workers in German hospitals-results from the OKaPII study]

BACKGROUND

Influenza vaccination coverage in Germany is generally low. Even in hospitals, the demand for influenza vaccination is lacking although it has the potential to prevent the spread of the influenza virus and diseases. To take effective actions, a deeper understanding of vaccination behavior of healthcare workers is crucial.

METHODS

OKaPII is an annual German-wide online survey of clinical staff on influenza vaccination. Differences in vaccination behavior were tested for occupation, sex, and age, and differences in knowledge were tested between physicians and nurses. We used logistic regressions to analyze associations between psychological determinants and vaccination behavior among physicians and nursing staff.

RESULTS

From 115 clinics, 15,312 employees participated in the survey (17 April to 15 May 2023). In the 2022/23 season, 58.7% of the participants were vaccinated against influenza. The vaccination coverage was 80.7% for physicians and 51.1% for nursing staff . The vaccination behavior of physicians and nursing staff was significantly associated with collective responsibility and confidence in vaccination safety. Of the knowledge items, 87.2% were answered correctly by physicians and 62% by nursing staff.

DISCUSSION

We identified significant differences in vaccine uptake between occupational groups in German hospitals. Low vaccination coverage has existed for years, especially among nursing staff. Tailored interventions should promote the idea of protecting vulnerable people and confidence in the safety of vaccination. Increased education, especially on vaccination safety issues, can have a positive impact on the decision to vaccinate. Possibilities to get vaccinated despite time constraints in the workplace should be provided.

Hospital-borne hazardous air pollutants and air cleaning strategies amid the surge of SARS-CoV-2 new variants

Indoor air pollutants and airborne contamination removal have been challenging in healthcare facilities. The airborne transmission control and HVAC system may collapse in hospitals due to the highly infectious respiratory disease-associated patient surge, like COVID-19. Common air filtration systems and HVAC systems enhance the patients' comfort and support indoor hygiene, hitherto insufficient to control highly infectious airborne pathogens and hospital-borne pollutants such as radon, PM2.5, patient droplets, VOC, high CO2, and anesthetic gases. This review summarized important air cleaning interventions to enhance HVAC efficiency and indoor safety. We discussed efficient air cleaning and ventilation strategies including air filtration, air ionization, passive removal materials (PRM), and UVGI to minimize cross-contamination in hospital wards.

Trends in SARS-CoV-2-related pediatric hospitalizations reported to the Canadian Nosocomial Infection Surveillance Program, March 2020 to December 2022

Objective

This study describes trends in COVID-19 hospitalizations and healthcare-associated (HA) COVID-19 in Canada among pediatric (age <18 years) patients during pre-Omicron and Omicron-dominant periods.

Design

Prospective surveillance for COVID-19 infection.

Setting

The Canadian Nosocomial Infection Surveillance Program is a sentinel surveillance system with 45 hospitals providing COVID-19 data on pediatric patients, including all 13 pediatric tertiary care facilities in Canada.

Patients

Pediatric patients hospitalized with laboratory-confirmed COVID-19 at a participating hospital between March 1, 2020, and December 31, 2022.

Methods

Analyzed case-level data on pediatric patients with COVID-19, including demographics, acquisition source, and outcomes.

Results

Among 5,143 pediatric cases, the majority (81%) were reported during the Omicron-dominant period (beginning December 26, 2021). However, a lower proportion required intensive care during the Omicron wave (11% vs 14%, P < 0.05); no difference in mortality was observed. Of those patients admitted to hospital due to COVID-19 (n = 2,700), 45% had at least one pre-existing comorbidity. The majority (90%) of patients with HA-COVID-19 were reported during the Omicron period. There was no difference in mortality between patients with HA and community-associated (CA) infection, although a greater proportion of CA infections led to intensive care unit admission (6% vs 13%, P < 0.01).

Conclusions

Surveillance findings indicate that both HA- and CA-COVID-19 hospitalizations in Canada increased among pediatric patients following the emergence of the Omicron variant, although disease severity decreased. Pre-existing health conditions were common among pediatric patients hospitalized with COVID-19, highlighting the importance of preventing severe illness in this sub-population.

COVID-19 seroprevalence cohort survey among health care workers and their household members in Kinshasa, DR Congo, 2020-2022

INTRODUCTION

Serological surveys offer the most direct measurement to define the immunity status for numerous infectious diseases, such as COVID-19, and can provide valuable insights into understanding transmission patterns. This study describes seroprevalence changes over time in the context of the Democratic Republic of Congo, where COVID-19 case presentation was apparently largely oligo- or asymptomatic, and vaccination coverage remained extremely low.

METHODS

A cohort of 635 health care workers (HCW) from 5 health zones of Kinshasa and 670 of their household members was interviewed and sampled in 6 rounds between July 2020 and January 2022. At each round, information on risk exposure and a blood sample were collected. Serology was defined as positive when binding antibodies against SARS-CoV-2 spike and nucleocapsid proteins were simultaneously present.

RESULTS

The SARS-CoV-2 antibody seroprevalence was high at baseline, 17.3% (95% CI 14.4-20.6) and 7.8% (95% CI 5.5-10.8) for HCW and household members, respectively, and fluctuated over time, between 9% and 62.1%. Seropositivity was heterogeneously distributed over the health zones (p < 0.001), ranging from 12.5% (95% CI 6.6-20.8) in N'djili to 33.7% (95% CI 24.6-43.8) in Bandalungwa at baseline for HCW. Seropositivity was associated with increasing rounds adjusted Odds Ratio (aOR) 1.75 (95% CI 1.66-1.85), with increasing age aOR 1.11 (95% CI 1.02-1.20), being a female aOR 1.35 (95% CI 1.10-1.66) and being a HCW aOR 2.38 (95% CI 1.80-3.14). There was no evidence that HCW brought the COVID-19 infection back home, with an aOR of 0.64 (95% CI 0.46-0.91) of seropositivity risk among household members in subsequent surveys. There was seroreversion and seroconversion over time, and HCW had a lower risk of seroreverting than household members (aOR 0.60 (95% CI 0.42-0.86)).

CONCLUSION

SARS-CoV-2 IgG antibody levels were high and dynamic over time in this African setting with low clinical case rates. The absence of association with health profession or general risk behaviors and with HCW positivity in subsequent rounds in HH members, shows the importance of the time-dependent, and not work-related, force of infection. Cohort seroprevalence estimates in a 'new disease' epidemic seem insufficient to guide policy makers for defining control strategies.

Diagnostic stewardship and the coronavirus disease 2019 (COVID-19) pandemic: Lessons learned for prevention of emerging infectious diseases in acute-care settings

The coronavirus disease 2019 (COVID-19) pandemic has demonstrated the importance of stewardship of viral diagnostic tests to aid infection prevention efforts in healthcare facilities. We highlight diagnostic stewardship lessons learned during the COVID-19 pandemic and discuss how diagnostic stewardship principles can inform management and mitigation of future emerging pathogens in acute-care settings. Diagnostic stewardship during the COVID-19 pandemic evolved as information regarding transmission (eg, routes, timing, and efficiency of transmission) became available. Diagnostic testing approaches varied depending on the availability of tests and when supplies and resources became available. Diagnostic stewardship lessons learned from the COVID-19 pandemic include the importance of prioritizing robust infection prevention mitigation controls above universal admission testing and considering preprocedure testing, contact tracing, and surveillance in the healthcare facility in certain scenarios. In the future, optimal diagnostic stewardship approaches should be tailored to specific pathogen virulence, transmissibility, and transmission routes, as well as disease severity, availability of effective treatments and vaccines, and timing of infectiousness relative to symptoms. This document is part of a series of papers developed by the Society of Healthcare Epidemiology of America on diagnostic stewardship in infection prevention and antibiotic stewardship.1.

In Support of Universal Admission Testing for SARS-CoV-2 During Significant Community Transmission

Many hospitals have stopped or are considering stopping universal admission testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We discuss reasons why admission testing should still be part of a layered system to prevent hospital-acquired SARS-CoV-2 infections during times of significant community transmission. These include the morbidity of SARS-CoV-2 in vulnerable patients, the predominant contribution of presymptomatic and asymptomatic people to transmission, the high rate of transmission between patients in shared rooms, and data suggesting surveillance testing is associated with fewer nosocomial infections. Preferences of diverse patient populations, particularly the hardest-hit communities, should be surveyed and used to inform prevention measures. Hospitals' ethical responsibility to protect patients from serious infections should predominate over concerns about costs, labor, and inconvenience. We call for more rigorous data on the incidence and morbidity of nosocomial SARS-CoV-2 infections and more research to help determine when to start, stop, and restart universal admission testing and other prevention measures.

Preventing and controlling intra-hospital spread of COVID-19 in Taiwan - Looking back and moving forward

COVID-19 has exposed major weaknesses in the healthcare settings. The surge in COVID-19 cases increases the demands of health care, endangers vulnerable patients, and threats occupational safety. In contrast to a hospital outbreak of SARS leading to a whole hospital quarantined, at least 54 hospital outbreaks following a COVID-19 surge in the community were controlled by strengthened infection prevention and control measures for preventing transmission from community to hospitals as well as within hospitals. Access control measures include establishing triage, epidemic clinics, and outdoor quarantine stations. Visitor access restriction is applied to inpatients to limit the number of visitors. Health monitoring and surveillance is applied to healthcare personnel, including self-reporting travel declaration, temperature, predefined symptoms, and test results. Isolation of the confirmed cases during the contagious period and quarantine of the close contacts during the incubation period are critical for containment. The target populations and frequency of SARS-CoV-2 PCR and rapid antigen testing depend on the level of transmission. Case investigation and contact tracing should be comprehensive to identify the close contacts to prevent further transmission. These facility-based infection prevention and control strategies help reduce hospital transmission of SARS-CoV-2 to a minimum in Taiwan.

Mortality amongst hospitalized COVID-19 cases by acquisition and pandemic wave in Wales, UK, February 2020-March 2022

BACKGROUND

Hospital populations are vulnerable to COVID-19, but the relative severity of hospital acquisition compared to community is unknown. We investigated differences in mortality between hospital and community acquired cases in Wales.

METHODS

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) polymerase chain reaction tests from February 2020 to March 2022 were linked with hospital admissions to identify likely hospital-acquired cases. All-cause mortality within 28 days of a positive SARS-CoV-2 were measured by source of acquisition. Multi-variable logistic regression was used to compare mortality by source of acquisition, adjusting for confounders, computing adjusted odds ratios (aOR) with 95% confidence intervals (CI).

RESULTS

There were 25,263 hospital-acquired cases of COVID-19 and 5490 (22%) deaths in the study period. Although significant on univariate analysis, adjustment for confounding showed no association with increased mortality for hospital-acquired cases compared with cases admitted with COVID-19 (aOR 0.8, 95% CI 0.7-0.8). Vaccination (aOR 0.6, 95% CI 0.5-0.7) and infection in later pandemic waves (aOR 0.5, 95% CI 0.4-0.6) were associated with lower mortality; older age (≥85 vs <25 years: aOR 76.4, 95% CI 41.8-160.5) and male sex (aOR 1.5, 95% CI 1.4-1.6) were associated with higher mortality.

CONCLUSION

One in five hospitalised COVID-19 cases died within a month of infection. Mortality in nosocomial cases was not worse than those admitted with COVID-19, possibly reflecting early identification of nosocomial cases through screening.

Comparison of clinical outcomes over time of inpatients with healthcare-associated or community-acquired coronavirus disease 2019 (COVID-19): A multicenter, prospective cohort study

OBJECTIVE

To compare clinical outcomes over time of inpatients with healthcare-associated coronavirus disease 2019 (HA-COVID-19) versus community-acquired COVID-19 (CA-COVID-19).

DESIGN

We conducted a multicenter, prospective observational cohort study of inpatients with COVID-19.

SETTING

The study was conducted across 16 acute-care hospitals in Switzerland.

PARTICIPANTS AND METHODS

We compared HA-COVID-19 cases, defined as patients with a positive severe acute respiratory coronavirus virus 2 (SARS-CoV-2) test > 5 days after hospital admission, with hospitalized CA-COVID-19 cases, defined as those who tested positive within 5 days of admission. The composite primary outcome was patient transfer to an intensive care unit (ICU) or an intermediate care unit (IMCU) and/or all-cause in-hospital mortality. We used cause-specific Cox regression and Fine-Gray regression to model the time to the composite clinical outcome, adjusting for confounders and accounting for the competing event of discharge from hospital. We compared our results to those from a conventional approach using an adjusted logistic regression model where time-varying effects and competitive risk were ignored.

RESULTS

Between February 19, 2020, and December 31, 2020, we included 1,337 HA-COVID-19 cases and 9,068 CA-COVID-19 cases. HA-COVID-19 patients were significantly older: median, 80 (interquartile range [IQR], 71-87) versus median 70 (IQR, 57-80) (P < .001). A greater proportion of HA-COVID-19 patients had a Charlson comorbidity index ≥ 5 (79% vs 55%; P < .001) than did CA-COVID-19 patients. In time-varying analyses, between day 0 and 8, HA-COVID-19 cases had a decreased risk of death or ICU or IMCU transfer compared to CA-COVID-19 cases (cause-specific hazard ratio [csHR], 0.43; 95% confidence interval [CI], 0.33-0.56). In contrast, from day 8 to 30, HA-COVID-19 cases had an increased risk of death or ICU or IMCU transfer (csHR, 1.49; 95% CI, 1.20-1.85), with no significant effect on the rate of discharge (csHR, 0.83; 95% CI, 0.61-1.14). In the conventional logistic regression model, HA-COVID-19 was protective against transfer to an ICU or IMCU and/or all-cause in-hospital mortality (adjusted odds ratio [aOR], 0.79, 95% CI, 0.67-0.93).

CONCLUSIONS

The risk of adverse clinical outcomes for HA-COVID-19 cases increased substantially over time in hospital and exceeded that for CA-COVID-19. Using approaches that do not account for time-varying effects or competing events may not fully capture the true risk of HA-COVID-19 compared to CA-COVID-19.

Evolution of illness severity in hospital admissions due to COVID-19, Québec, Canada, January to April 2022

Background

The coronavirus disease 2019 (COVID-19) severity is influenced by multiple factors, such as age, underlying medical conditions, individual immunity, infecting variant, and clinical practice. The highly transmissible Omicron variants resulted in decreased COVID-19 screening capacity, which limited disease severity surveillance.

Objective

To report on the temporal evolution of disease severity among patients admitted to Québec hospitals due to COVID-19 between January 2, 2022, and April 23, 2022, which corresponded to the peak period of hospitalizations due to Omicron.

Methods

Retrospective population-based cohort study of all hospital admissions due to COVID-19 in Québec, between January 2, 2022, and April 23, 2022. Study period was divided into four-week periods, corresponding roughly to January, February, March and April. Regression using Cox and Poisson generalized estimating equations (GEEs) was used to quantify temporal variations in length of stay and risk of complications (intensive care admission or in-hospital death) through time, using the Omicron peak (January 2022) as reference. Measures were adjusted for age, sex, vaccination status, presence of chronic diseases, and clustering by hospital.

Results

During the study period, 9,178 of all 18,272 (50.2%) patients hospitalized with a COVID-19 diagnosis were admitted due to COVID-19. Of these, 1,026 (11.2%) were admitted to intensive care and 1,523 (16.6%) died. Compared to January, the risk of intensive care admission was 25% and 31% lower in March and April respectively, while in-hospital fatality continuously decreased by 45% lower in April. The average length of stay was temporarily lower in March (9%).

Conclusion

Severity of admissions due to COVID-19 decreased in the first months of 2022, when predominant circulating variants were considered to be of similar severity. Monitoring hospital admissions due to COVID-19 can contribute to disease severity surveillance.

Nosocomial Coronavirus Disease 2019 during 2020-2021: Role of Architecture and Ventilation

Nosocomial coronavirus disease 2019 (COVID-19) is a major airborne health threat for inpatients. Architecture and ventilation are key elements to prevent nosocomial COVID-19 (NC), but real-life data are challenging to collect. We aimed to retrospectively assess the impact of the type of ventilation and the ratio of single/double rooms on the risk of NC (acquisition of COVID-19 at least 48 h after admission). This study was conducted in a tertiary hospital composed of two main structures (one historical and one modern), which were the sites of acquisition of NC: historical (H) (natural ventilation, 53% single rooms) or modern (M) hospital (double-flow mechanical ventilation, 91% single rooms). During the study period (1 October 2020 to 31 May 2021), 1020 patients presented with COVID-19, with 150 (14.7%) of them being NC (median delay of acquisition, 12 days). As compared with non-nosocomial cases, the patients with NC were older (79 years vs. 72 years; p < 0.001) and exhibited higher mortality risk (32.7% vs. 14.1%; p < 0.001). Among the 150 NC cases, 99.3% were diagnosed in H, mainly in four medical departments. A total of 73 cases were diagnosed in single rooms versus 77 in double rooms, including 26 secondary cases. Measured air changes per hour were lower in H than in M. We hypothesized that in H, SARS-CoV-2 transmission was favored by short-range transmission within a high ratio of double rooms, but also during clusters, via far-afield transmission through virus-laden aerosols favored by low air changes per hour. A better knowledge of the mechanism of airborne risk in healthcare establishments should lead to the implementation of corrective measures when necessary. People's health is improved using not only personal but also collective protective equipment, i.e., ventilation and architecture, thereby reinforcing the need to change institutional and professional practices.

Nosocomial SARS-CoV-2 Infections and Mortality During Unique COVID-19 Epidemic Waves

Importance

Quantifying the burden of nosocomial SARS-CoV-2 infections and associated mortality is necessary to assess the need for infection prevention and control measures.

Objective

To investigate the occurrence of nosocomial SARS-CoV-2 infections and associated 30-day mortality among patients admitted to hospitals in Region Stockholm, Sweden.

Design, Setting, and Participants

A retrospective, matched cohort study divided the period from March 1, 2020, until September 15, 2022, into a prevaccination period, early vaccination and pre-Omicron (period 1), and late vaccination and Omicron (period 2). From among 303 898 patients 18 years or older living in Region Stockholm, 538 951 hospital admissions across all hospitals were included. Hospitalized admissions with nosocomial SARS-CoV-2 infections were matched to as many as 5 hospitalized admissions without nosocomial SARS-CoV-2 by age, sex, length of stay, admission time, and hospital unit.

Exposure

Nosocomial SARS-CoV-2 infection defined as the first positive polymerase chain reaction test result at least 8 days after hospital admission or within 2 days after discharge.

Main Outcomes and Measures

Primary outcome of 30-day mortality was analyzed using time-to-event analyses with a Cox proportional hazards regression model adjusted for age, sex, educational level, and comorbidities.

Results

Among 2193 patients with SARS-CoV-2 infections or reinfections (1107 women [50.5%]; median age, 80 [IQR, 71-87] years), 2203 nosocomial SARS-CoV-2 infections were identified. The incidence rate of nosocomial SARS-CoV-2 infections was 1.57 (95% CI, 1.51-1.64) per 1000 patient-days. In the matched cohort, 1487 hospital admissions with nosocomial SARS-CoV-2 infections were matched to 5044 hospital admissions without nosocomial SARS-CoV-2 infections. Thirty-day mortality was higher in the prevaccination period (adjusted hazard ratio [AHR], 2.97 [95% CI, 2.50-3.53]) compared with period 1 (AHR, 2.08 [95% CI, 1.50-2.88]) or period 2 (AHR, 1.22 [95% CI, 0.92-1.60]). Among patients with nosocomial SARS-CoV-2 infections, 30-day AHR comparing those with 2 or more doses of SARS-CoV-2 vaccination and those with less than 2 doses was 0.64 (95% CI, 0.46-0.88).

Conclusions and Relevance

In this matched cohort study, nosocomial SARS-CoV-2 infections were associated with higher 30-day mortality during the early phases of the pandemic and lower mortality during the Omicron variant wave and after the introduction of vaccinations. Mitigation of excess mortality risk from nosocomial transmission should be a strong focus when population immunity is low through implementation of adequate infection prevention and control measures.

Regional Variations in Coronavirus Disease 2019 Mortality in Japan: An Ecological Study

Introduction

As the characteristics of coronavirus disease 2019 (COVID-19) vary across regions and countries, the relationship between regional characteristics, such as the distribution of physicians and hospital beds, and COVID-19 mortality was assessed in the 47 prefectures of Japan.

Methods

This ecological study was based on the number of patients with COVID-19 by prefecture during the seventh wave of COVID-19 in Japan (June-October 2022). COVID-19 mortality was indexed as the number of COVID-19 deaths divided by the number of new COVID-19 cases. Data on regional factors, such as population size, number of physicians, and hospital beds by prefecture, were obtained from government statistics. Correlations between regional characteristics and COVID-19 mortality index were analyzed by dividing the 47 prefectures into two groups at the median level of population size (more populated group [MPG] ≥ 1.6 million and less populated group [LPG] < 1.6 million).

Results

The COVID-19 mortality index (mean 12.7, minimum-maximum: 4.7-25.7) was correlated negatively with the number of physicians per hospital bed (r = -0.386, p = 0.007) and positively with the number of long-term care facilities per 10,000 population (r = 0.397, p = 0.006) and aging rate (the proportion of population aged ≥ 65 years) (r = 0.471, p = 0.001). The two groups varied with respect to the number of physicians (28.7 physicians in the LPG vs. 26.1 physicians in the MPG, p = 0.038) and hospital beds (156 beds in the LPG vs. 119 beds in the MPG, p < 0.001) per 10,000 population. In the multiple regression analysis, the COVID-19 mortality index was correlated negatively with the number of physicians per hospital bed (β = -0.543, p = 0.024) and positively with the aging rate (β = 0.434, p = 0.032) in the LPG, with nonsignificant correlations in the MPG.

Conclusions

The data may suggest a need of improvement in the distribution of physicians and hospital beds in the healthcare system in regions with smaller and older populations to reduce the rate of COVID-19.

Whole-genome sequencing to investigate transmission of SARS-CoV-2 in the acute healthcare setting: a systematic review

BACKGROUND

Whole-genome sequencing (WGS) has been used widely to elucidate transmission of SARS-CoV-2 in acute healthcare settings, and to guide infection, prevention, and control (IPC) responses.

AIM

To systematically appraise available literature, published between January 1st, 2020 and June 30th, 2022, describing the implementation of WGS in acute healthcare settings to characterize nosocomial SARS-CoV-2 transmission.

METHODS

Searches of the PubMed, Embase, Ovid MEDLINE, EBSCO MEDLINE, and Cochrane Library databases identified studies in English reporting the use of WGS to investigate SARS-CoV-2 transmission in acute healthcare environments. Publications involved data collected up to December 31st, 2021, and findings were reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement.

FINDINGS

In all, 3088 non-duplicate records were retrieved; 97 met inclusion criteria, involving 62 outbreak analyses and 35 genomic surveillance studies. No publications from low-income countries were identified. In 87/97 (90%), WGS supported hypotheses for nosocomial transmission, while in 46 out of 97 (47%) suspected transmission events were excluded. An IPC intervention was attributed to the use of WGS in 18 out of 97 (18%); however, only three (3%) studies reported turnaround times ≤7 days facilitating near real-time IPC action, and none reported an impact on the incidence of nosocomial COVID-19 attributable to WGS.

CONCLUSION

WGS can elucidate transmission of SARS-CoV-2 in acute healthcare settings to enhance epidemiological investigations. However, evidence was not identified to support sequencing as an intervention to reduce the incidence of SARS-CoV-2 in hospital or to alter the trajectory of active outbreaks.

COVID-19 clusters in Malaysia: characteristics, detection methods and modes of early transmission

Objective

Effective prevention and control measures are essential to contain outbreaks of infectious diseases, such as coronavirus disease (COVID-19). Understanding the characteristics of case clusters can contribute to determining which prevention and control measures are needed. This study describes the characteristics of COVID-19 case clusters in Malaysia, the method used to detect a cluster's index case and the mode of early transmission, using the seven cluster categories applied in Malaysia.

Methods

This cross-sectional study collected publicly available data on COVID-19 clusters occurring in Malaysia from 1 March 2020 to 31 May 2021. The characteristics of cases were described by category, and their associations with several outcomes were analysed. Descriptive analyses were performed to explore the method used to detect the index case and the mode of early transmission, according to cluster category.

Results

A total of 2188 clusters were identified. The workplace cluster category had the largest proportion of clusters (51.5%, 1126/2188 clusters), while the custodial settings category had the largest median cluster size (178 cases per cluster) and longest median duration of cluster (51 days). The high-risk groups category had the highest mortality. There were significant differences in cluster size, duration and rate of detection across the categories. Targeted screening was most commonly used to detect index cases, especially in custodial settings, and in imported and workplace clusters. Household-social and social-workplace contacts were the most common modes of early transmission across most categories.

Discussion

Targeted screening might effectively reduce the size and duration of COVID-19 clusters. Measures to prevent and control COVID-19 outbreaks should be continually adjusted based on ongoing assessments of the unique context of each cluster.

Rationale for the shielding policy for clinically vulnerable people in the UK during the COVID-19 pandemic: a qualitative study

INTRODUCTION

Shielding aimed to protect those predicted to be at highest risk from COVID-19 and was uniquely implemented in the UK during the first year of the pandemic from March 2020. As the first stage in the EVITE Immunity evaluation (Effects of shielding for vulnerable people during COVID-19 pandemic on health outcomes, costs and immunity, including those with cancer:quasi-experimental evaluation), we generated a logic model to describe the programme theory underlying the shielding intervention.

DESIGN AND PARTICIPANTS

We reviewed published documentation on shielding to develop an initial draft of the logic model. We then discussed this draft during interviews with 13 key stakeholders involved in putting shielding into effect in Wales and England. Interviews were recorded, transcribed and analysed thematically to inform a final draft of the logic model.

RESULTS

The shielding intervention was a complex one, introduced at pace by multiple agencies working together. We identified three core components: agreement on clinical criteria; development of the list of people appropriate for shielding; and communication of shielding advice. In addition, there was a support programme, available as required to shielding people, including food parcels, financial support and social support. The predicted mechanism of change was that people would isolate themselves and so avoid infection, with the primary intended outcome being reduction in mortality in the shielding group. Unintended impacts included negative impact on mental and physical health and well-being. Details of the intervention varied slightly across the home nations of the UK and were subject to minor revisions during the time the intervention was in place.

CONCLUSIONS

Shielding was a largely untested strategy, aiming to mitigate risk by placing a responsibility on individuals to protect themselves. The model of its rationale, components and outcomes (intended and unintended) will inform evaluation of the impact of shielding and help us to understand its effect and limitations.

Clinical characteristics and outcomes of nosocomial COVID-19 in Turkey: A retrospective multicenter study

Objective:

To identify the clinical characteristics and outcomes of hospital-acquired SARS-CoV-2 infection during the vaccination period nationwide in Turkey.

Methods:

COVID-19 patients followed in the pandemic services across Turkey between January 1, 2021, and March 31, 2022 were investigated retrospectively. Nosocomial COVID-19 was defined as a patient neither diagnosed with COVID-19 nor suspected COVID-19 at the hospital admission and was confirmed COVID-19 ≥5 days after hospital admission. The primary outcome of this study was in-hospital mortality; demographic features and vaccination status was compared between survivors and non-survivors.

Results:

During the study period, 15 573 COVID-19 patients were followed in 18 centers and 543 (3.5%) patients were nosocomial COVID-19. Most patients with nosocomial COVID-19 (80.4%) were transferred from medical wards. 162 (29.8%) of the patients with nosocomial COVID-19 admitted to the intensive care unit due to disease severity and 138 (25.4%) of the patients died during hospital stay. Advanced age (≥65 years) and number of comorbid diseases (≥2) was found to be associated with mortality in nosocomial COVID-19 (OR 1.74, 95% Cl 1.11-2.74 and OR 1.60, 95% Cl 1.02-2.56, respectively). Vaccination was associated with survival in nosocomial COVID-19 (OR 0.25, 95% Cl 0.16-0.38).

Conclusions:

Patients with nosocomial COVID-19 had increased admission to intensive care units and higher mortality rate. Vaccination can decrease the in-hospital mortality rate.

Considerations for de-escalating universal masking in healthcare centers

Three years after the beginning of the COVID-19 pandemic, better knowledge on the transmission of respiratory viral infections (RVI) including the contribution of asymptomatic infections encouraged most healthcare centers to implement universal masking. The evolution of the SARS-CoV-2 epidemiology and improved immunization of the population call for the infection and prevention control community to revisit the masking strategy in healthcare. In this narrative review, we consider factors for de-escalating universal masking in healthcare centers, addressing compliance with the mask policy, local epidemiology, the level of protection provided by medical face masks, the consequences of absenteeism and presenteeism, as well as logistics, costs, and ecological impact. Most current national and international guidelines for mask use are based on the level of community transmission of SARS-CoV-2. Actions are now required to refine future recommendations, such as establishing a list of the most relevant RVI to consider, implement reliable local RVI surveillance, and define thresholds for activating masking strategies. Considering the epidemiological context (measured via sentinel networks or wastewater analysis), and, if not available, considering a time period (winter season) may guide to three gradual levels of masking: (i) standard and transmission-based precautions and respiratory etiquette, (ii) systematic face mask wearing when in direct contact with patients, and (iii) universal masking. Cost-effectiveness analysis of the different strategies is warranted in the coming years. Masking is just one element to be considered along with other preventive measures such as staff and patient immunization, and efficient ventilation.

Ventilation strategies based on an aerodynamic analysis during a large-scale SARS-CoV-2 outbreak in an acute-care hospital

BACKGROUND

This study aimed to investigate ventilation strategies to prevent nosocomial transmission of coronavirus disease 2019 (COVID-19).

METHODS

We conducted a retrospective epidemiological investigation of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreak in a teaching hospital (February-March 2021). The largest outbreak ward was studied, and measurements were taken to determine the pressure difference and air change per hour (ACH) of the rooms. Airflow dynamics were assessed using an oil droplet generator, indoor air quality sensor, and particle image velocimetry in the index patient's room, corridor, and opposite rooms, by varying the opening and closing of windows and doors.

RESULTS

During the outbreak, 283 COVID-19 cases were identified. The SARS-CoV-2 spread occurred sequentially from the index room to the nearest room, especially the opposite. The aerodynamic study demonstrated that droplet-like particles in the index room diffused through the corridor and the opposite room through the opening door. The mean ACH of the rooms was 1.44; the air supply volume was 15.9% larger than the exhaust volume, forming a positive pressure. Closing the door prevented diffusion between adjacent rooms facing each other, and natural ventilation reduced the concentration of particles within the ward and minimised their spread to adjacent rooms.

CONCLUSIONS

Spread of droplet-like particles between rooms could be attributed to the pressure difference between the rooms and corridor. To prevent spread of SARS-CoV-2 between rooms, increasing the ACH in the room by maximising ventilation and minimising the positive pressure through supply/exhaust control and closing the room door are essential.

Vaccine effectiveness of the mRNA-1273 3-dose primary series against COVID-19 in an immunocompromised population: A prospective observational cohort study

BACKGROUND

Data on the effectiveness of the 3-dose mRNA-1273 primary series are limited, particularly in comparison to 2 doses. Given suboptimal COVID-19 vaccine uptake among immunocompromised populations, it is important to monitor the effectiveness of fewer than the recommended doses in this population.

METHODS

We conducted a matched cohort study at Kaiser Permanente Southern California to evaluate the relative vaccine effectiveness (rVE) of the 3-dose series vs 2 doses of mRNA-1273 in preventing SARS-CoV-2 infection and severe COVID-19 outcomes among immunocompromised individuals.

RESULTS

We included 21,942 3-dose recipients who were 1:1 matched with randomly selected 2-dose recipients (third doses accrued 08/12/2021-12/31/2021, with follow-up through 01/31/2022). Adjusted rVE of 3 vs 2 doses of mRNA-1273 against SARS-CoV-2 infection, COVID-19 hospitalization, and COVID-19 hospital death were 55.0 % (95 % CI: 50.8-58.9 %), 83.0 % (75.4-88.3 %), and 87.1 % (30.6-97.6 %), respectively.

CONCLUSION

Three doses of mRNA-1273 were associated with a significantly higher rVE against SARS-CoV-2 infection and severe outcomes, compared to 2 doses. These findings were consistent across subgroups of demographic and clinical characteristics, and mostly consistent across subgroups of immunocompromising conditions. Our study highlights the importance of completing the 3-dose series for immunocompromised populations.

Did the UK's public health shielding policy protect the clinically extremely vulnerable during the COVID-19 pandemic in Wales? Results of EVITE Immunity, a linked data retrospective study

INTRODUCTION

The UK shielding policy intended to protect people at the highest risk of harm from COVID-19 infection. We aimed to describe intervention effects in Wales at 1 year.

METHODS

Retrospective comparison of linked demographic and clinical data for cohorts comprising people identified for shielding from 23 March to 21 May 2020; and the rest of the population. Health records were extracted with event dates between 23 March 2020 and 22 March 2021 for the comparator cohort and from the date of inclusion until 1 year later for the shielded cohort.

RESULTS

The shielded cohort included 117,415 people, with 3,086,385 in the comparator cohort. The largest clinical categories in the shielded cohort were severe respiratory condition (35.5%), immunosuppressive therapy (25.9%) and cancer (18.6%). People in the shielded cohort were more likely to be female, aged ≥50 years, living in relatively deprived areas, care home residents and frail. The proportion of people tested for COVID-19 was higher in the shielded cohort (odds ratio [OR] 1.616; 95% confidence interval [CI] 1.597-1.637), with lower positivity rate incident rate ratios 0.716 (95% CI 0.697-0.736). The known infection rate was higher in the shielded cohort (5.9% vs 5.7%). People in the shielded cohort were more likely to die (OR 3.683; 95% CI: 3.583-3.786), have a critical care admission (OR 3.339; 95% CI: 3.111-3.583), hospital emergency admission (OR 2.883; 95% CI: 2.837-2.930), emergency department attendance (OR 1.893; 95% CI: 1.867-1.919) and common mental disorder (OR 1.762; 95% CI: 1.735-1.789).

CONCLUSION

Deaths and healthcare utilisation were higher amongst shielded people than the general population, as would be expected in the sicker population. Differences in testing rates, deprivation and pre-existing health are potential confounders; however, lack of clear impact on infection rates raises questions about the success of shielding and indicates that further research is required to fully evaluate this national policy intervention.

Contributory conditions for unexpected COVID-19 cases and nosocomial COVID-19 infection cases identified from systematic investigation in a French University Hospital

INTRODUCTION

Nosocomial case (NC) of COVID-19 infections is a challenge for hospitals. We report the results of a seven-month prospective cohort study investigating COVID-19 patients to assess unexpected cases (UC) (no COVID-19 precautionary measure application since admission) and NC.

PATIENTS AND METHODS

Investigation by an infection control team of 844 patients with COVID-19 infection hospitalized for more than 24 hours (cases).

RESULTS

A total of 301 UC were identified (31% after contact tracing) with a total of 129 contact patients, and 27 secondary cases for 59 of them. In geriatric wards, 50% of cases were UC. NC represented 18% of cases (37% in geriatric wards), mainly identified after contact tracing of wandering cases.

CONCLUSION

A rapid infection control response is essential to contain nosocomial transmission, along with detailed contact tracing and screening policy. Dealing with wandering elderly patients remain challenging for HCWs.

Identifying Adverse Events in Patients Hospitalized in Isolation or Quarantine Due to COVID-19

BACKGROUND

This study evaluated the adverse events of COVID-19 isolation or quarantine in patients with nosocomial SARS-CoV-2 infection admitted to the Hospital Universitario Insular de Gran Canaria.

METHODS

This is a retrospective cohort study with 30-day follow-up of 126 patients diagnosed with nosocomial COVID-19 through polymerase chain reaction test, between May 1 and June 30, 2022, in a 500-bed university hospital in the island of Gran Canaria.

RESULTS

Between May 1 and July 30, 2022, a total of 2250 patients were admitted to the Hospital Universitario Insular de Gran Canaria; 126 of them were diagnosed with nosocomial COVID-19 through a polymerase chain reaction test. The rate of nosocomial COVID-19 infection was 5.6%. From the 126 patients of the study population, 27 experienced an adverse event (21.4%) and 2 experienced 2 adverse events (1.6%) due to COVID-19 isolation or quarantine. Thus, a total of 31 adverse events occurred in 29 patients. These events included the following: delay in transfer to other centers of 11 patients who were pending of receiving a negative COVID-19 test result (35.5%), delay or cancellation of diagnostic tests in 9 patients (29%), delay or cancellation of doctor visit in 7 patients (22.6%), and delay or cancellation of surgical or other interventions in 4 patients (12.9%).

CONCLUSIONS

Because of the adverse consequences of nosocomial COVID-19 infection in hospitalized patients, measures should be observed for the prevention and control of nosocomial infection transmission, and adverse events related to patient safety issues in health care in isolated or quarantined COVID-19 patients should be prevented.

Risk factors for nosocomial COVID-19 in a French university hospital

OBJECTIVES

Prevention strategies implemented by hospitals to reduce nosocomial transmission of SARS-CoV-2 sometimes failed. Our aim was to determine the risk factors for nosocomial COVID-19.

PATIENTS AND METHODS

A case-control study was conducted (September 1, 2020-January 31, 2021) with adult patients hospitalized in medical or surgical units. Infants or patients hospitalized in ICU were excluded. Cases were patients with nosocomial COVID-19 (clinical symptoms and RT-PCR+ for SARS-CoV-2 or RT-PCR+ for SARS-CoV-2 with Ct ≤28 more than 5days after admission); controls were patients without infection (RT-PCR- for SARS-CoV-2 >5 days after admission). They were matched according to length of stay before diagnosis and period of admission. Analyses were performed with a conditional logistic regression.

RESULTS

A total of 281 cases and 441 controls were included. In the bivariate analysis, cases were older (OR per 10years: 1.22; 95%CI [1.10;1.36]), had more often shared a room (OR: 1.74; 95%CI [1.25;2.43]) or a risk factor for severe COVID-19 (OR: 1.94; 95%CI [1.09;3.45]), were more often hospitalized in medical units [OR: 1.59; 95%CI [1.12;2.25]), had higher exposure to contagious health care workers (HCW; OR per 1person-day: 1.12; 95%CI [1.08;1.17]) and patients (OR per 1 person-day: 1.11; 95%CI [1.08;1.14]) than controls. In an adjusted model, risk factors for nosocomial COVID-19 were exposure to contagious HCW (aOR per 1person-day: 1.08; 95%CI [1.03;1.14]) and to contagious patients (aOR per 1person-day: 1.10; 95%CI [1.07;1.13]).

CONCLUSIONS

Exposure to contagious professionals and patients are the main risk factors for nosocomial COVID-19.

SARS-CoV-2 antigen rapid tests and universal screening for COVID-19 Omicron variant among hospitalized children

BACKGROUND

Clinical utility of universal antigen rapid test (ART) in the pediatric setting is unknown. We aimed to assess the performance and utility of universal ART in hospitalized children (≥5-year-old) to prevent nosocomial COVID-19 transmission.

METHODS

Cross-sectional study involving all hospitalized pediatric patients aged ≥5-year-old from 2 periods during Omicron wave. Clinical data, ART and polymerase chain reaction test results were collected.

RESULTS

A total of 444 patients were included from the 2 study periods, and 416 patients (93.7%) had concordant results between ART and polymerase chain reaction. The overall sensitivity and specificity of ART were 83.3% (95% CI: 75.2-89.3) and 97.5% (95% CI: 95.0-98.8), respectively. Negative predictive values of ART between the Omicron emergence and Omicron peak periods for a probable case group were 71.4% and 66.7%, respectively, and for a suspect case group 91.4% and 75.0%, respectively. Negative predictive values for an unlikely case group was >95% in both periods. Positive predictive value of ART was >85% for probable and suspect case groups in both periods. Seventy-five percent of patients (n = 15) who were incorrectly classified as SARS-CoV-2 negative by ART had potentially viable virus. No large nosocomial transmission clusters were detected.

CONCLUSIONS

Universal ART screening may limit nosocomial outbreaks in hospitalized children. The performance can be optimized by considering clinical symptoms, exposure and periods within COVID waves.

Surveillance for SARS-CoV-2 and its variants in wastewater of tertiary care hospitals correlates with increasing case burden and outbreaks

Wastewater-based SARS-CoV-2 surveillance enables unbiased and comprehensive monitoring of defined sewersheds. We performed real-time monitoring of hospital wastewater that differentiated Delta and Omicron variants within total SARS-CoV-2-RNA, enabling correlation to COVID-19 cases from three tertiary-care facilities with >2100 inpatient beds in Calgary, Canada. RNA was extracted from hospital wastewater between August/2021 and January/2022, and SARS-CoV-2 quantified using RT-qPCR. Assays targeting R203M and R203K/G204R established the proportional abundance of Delta and Omicron, respectively. Total and variant-specific SARS-CoV-2 in wastewater was compared to data for variant specific COVID-19 hospitalizations, hospital-acquired infections, and outbreaks. Ninety-six percent (188/196) of wastewater samples were SARS-CoV-2 positive. Total SARS-CoV-2 RNA levels in wastewater increased in tandem with total prevalent cases (Delta plus Omicron). Variant-specific assessments showed this increase to be mainly driven by Omicron. Hospital-acquired cases of COVID-19 were associated with large spikes in wastewater SARS-CoV-2 and levels were significantly increased during outbreaks relative to nonoutbreak periods for total SARS-CoV2, Delta and Omicron. SARS-CoV-2 in hospital wastewater was significantly higher during the Omicron-wave irrespective of outbreaks. Wastewater-based monitoring of SARS-CoV-2 and its variants represents a novel tool for passive COVID-19 infection surveillance, case identification, containment, and potentially to mitigate viral spread in hospitals.

Transmission of COVID-19 in Nightlife, Household, and Health Care Settings in Tokyo, Japan, in 2020

IMPORTANCE

There have been few studies on the heterogeneous interconnection of COVID-19 outbreaks occurring in different social settings using robust, surveillance epidemiological data.

OBJECTIVES

To describe the characteristics of COVID-19 transmission within different social settings and to evaluate settings associated with onward transmission to other settings.

DESIGN, SETTING, AND PARTICIPANTS

This is a case series study of laboratory-confirmed COVID-19 cases in Tokyo between January 23 and December 5, 2020, when vaccination was not yet implemented. Using epidemiological investigation data collected by public health centers, epidemiological links were identified and classified into 7 transmission settings: imported, nightlife, dining, workplace, household, health care, and other.

MAIN OUTCOMES AND MEASURES

The number of cases per setting and the likelihood of generating onward transmissions were compared between different transmission settings.

RESULTS

Of the 44 054 confirmed COVID-19 cases in this study, 25 241 (57.3%) were among male patients, and the median (IQR) age of patients was 36 (26-52) years. Transmission settings were identified in 13 122 cases, including 6768 household, 2733 health care, and 1174 nightlife cases. More than 6600 transmission settings were detected, and nightlife (72 of 380 [18.9%]; P < .001) and health care (119 [36.2%]; P < .001) settings were more likely to involve 5 or more cases than dining, workplace, household, and other settings. Nightlife cases appeared in the earlier phase of the epidemic, while household and health care cases appeared later. After adjustment for transmission setting, sex, age group, presence of symptoms, and wave, household and health care cases were less likely to generate onward transmission compared with nightlife cases (household: adjusted odds ratio, 0.03; 95% CI, 0.02-0.05; health care: adjusted odds ratio, 0.57; 95% CI, 0.41-0.79). Household settings were associated with intergenerational transmission, while nonhousehold settings mainly comprised transmission between the same age group. Among 30 932 cases without identified transmission settings, cases with a history of visiting nightlife establishments were more likely to generate onward transmission to nonhousehold settings (adjusted odds ratio, 5.30 [95% CI, 4.64-6.05]; P < .001) than those without such history.

CONCLUSIONS AND RELEVANCE

In this case series study, COVID-19 cases identified in nightlife settings were associated with a higher likelihood of spreading COVID-19 than household and health care cases. Surveillance and interventions targeting nightlife settings should be prioritized to disrupt COVID-19 transmission, especially in the early stage of an epidemic.

Is there a role for RDTs as we live with COVID-19? An assessment of different strategies

INTRODUCTION

By 2022, high levels of past COVID-19 infections, combined with substantial levels of vaccination and the development of Omicron, have shifted country strategies towards burden reduction policies. SARS-CoV-2 rapid antigen tests (rapid diagnostic tests (RDTs)) could contribute to these policies by helping rapidly detect, isolate and/or treat infections in different settings. However, the evidence to inform RDT policy choices in low and middle-income countries (LMICs) is limited.

METHOD

We provide an overview of the potential impact of several RDT use cases (surveillance; testing, tracing and isolation without and with surveillance; hospital-based screening to reduce nosocomial COVID-19; and testing to enable earlier/expanded treatment) for a range of country settings. We use conceptual models and literature review to identify which use cases are likely to bring benefits and how these may change with outbreak characteristics. Impacts are measured through multiple outcomes related to gaining time, reducing the burden on the health system and reducing deaths.

RESULTS

In an optimal scenario in terms of resources and capacity and with baseline parameters, we find marginal time gains of 4 days or more through surveillance and testing tracing and isolation with surveillance, a reduction in peak intensive care unit (ICU) or ICU admissions by 5% or more (hospital-based screening; testing, tracing and isolation) and reductions in COVID-19 deaths by over 6% (hospital-based screening; test and treat). Time gains may be used to strengthen ICU capacity and/or boost vulnerable individuals, though only a small minority of at-risk individuals could be reached in the time available. The impact of RDTs declines with lower country resources and capacity, more transmissible or immune-escaping variants and reduced test sensitivity.

CONCLUSION

RDTs alone are unlikely to dramatically reduce the burden of COVID-19 in LMICs, though they may have an important role alongside other interventions such as vaccination, therapeutic drugs, improved healthcare capacity and non-pharmaceutical measures.

Detection of hospital environmental contamination during SARS-CoV-2 Omicron predominance using a highly sensitive air sampling device

Background and objectives

The high transmissibility of SARS-CoV-2 has exposed weaknesses in our infection control and detection measures, particularly in healthcare settings. Aerial sampling has evolved from passive impact filters to active sampling using negative pressure to expose culture substrate for virus detection. We evaluated the effectiveness of an active air sampling device as a potential surveillance system in detecting hospital pathogens, for augmenting containment measures to prevent nosocomial transmission, using SARS-CoV-2 as a surrogate.

Methods

We conducted air sampling in a hospital environment using the AerosolSense^TM air sampling device and compared it with surface swabs for their capacity to detect SARS-CoV-2.

Results

When combined with RT-qPCR detection, we found the device provided consistent SARS-CoV-2 detection, compared to surface sampling, in as little as 2 h of sampling time. The device also showed that it can identify minute quantities of SARS-CoV-2 in designated "clean areas" and through a N95 mask, indicating good surveillance capacity and sensitivity of the device in hospital settings.

Conclusion

Active air sampling was shown to be a sensitive surveillance system in healthcare settings. Findings from this study can also be applied in an organism agnostic manner for surveillance in the hospital, improving our ability to contain and prevent nosocomial outbreaks.

Immunodeficient patient experience of emergency switch from intravenous to rapid push subcutaneous immunoglobulin replacement therapy during coronavirus disease 2019 shielding

PURPOSE OF REVIEW

Welsh immunodeficient patients on immunoglobulin replacement therapy (IgRT) who were considered high risk for severe coronavirus disease 2019 (COVID-19) were directed to shield. Consequently, patients receiving hospital-based intravenous immunoglobulin (IVIg) quickly transitioned to home-based self-administered subcutaneous immunoglobulin (SCIg). This evaluation aimed to assess patients' perceptions and experiences and laboratory outcomes of emergency IgRT transition during COVID-19.

RECENT FINDINGS

A quick transition from in-hospital IVIg to home-based rapid push SCIg is achievable, however, patient IgRT administration preference remains key outside of emergency shielding measures.

SUMMARY

Subjective self-reported experiences ( n  = 23) and objective immunoglobulin G (IgG) concentration ( n  = 28) assessments were prospectively collected from patients pre/post-IgRT switch. In total, 41/55 (75%) patients transitioned from IVIg to rapid push SCIg and all completed training to self-administer subcutaneously within 24 days. Twenty-two percent ( n  = 5) of patients preferred SCIg and 35% ( n  = 8) wanted to return to hospital-based IVIg at 6 weeks post-transition. Mean IgG levels were similar pre vs. post-SCIg switch (10.3 g/l vs. 10.6 g/l, respectively). Patients reported greater infection anxiety during COVID-19 and adapted behaviours to mitigate risk. Although a third of patients wished to return to IVIg following cessation of shielding, over time the percentage electing to remain on SCIg rose from 22% to 59%.

A Population-Based Analysis of the Risk of Glomerular Disease Relapse after COVID-19 Vaccination

BACKGROUND

Although case reports have described relapses of glomerular disease after COVID-19 vaccination, evidence of a true association is lacking. In this population-level analysis, we sought to determine relative and absolute risks of glomerular disease relapse after COVID-19 vaccination.

METHODS

In this retrospective population-level cohort study, we used a centralized clinical and pathology registry (2000-2020) to identify 1105 adult patients in British Columbia, Canada, with biopsy-proven glomerular disease that was stable on December 14, 2020 (when COVID-19 vaccines first became available). The primary outcome was disease relapse, on the basis of changes in kidney function, proteinuria, or both. Vaccination was modeled as a 30-day time-varying exposure in extended Cox regression models, stratified on disease type.

RESULTS

During 281 days of follow-up, 134 (12.1%) patients experienced a relapse. Although a first vaccine dose was not associated with relapse risk (hazard ratio [HR]=0.67; 95% confidence interval [95% CI], 0.33 to 1.36), exposure to a second or third dose was associated with a two-fold risk of relapse (HR=2.23; 95% CI, 1.06 to 4.71). The pattern of relative risk was similar across glomerular diseases. The absolute increase in 30-day relapse risk associated with a second or third vaccine dose varied from 1%-2% in ANCA-related glomerulonephritis, minimal change disease, membranous nephropathy, or FSGS to 3%-5% in IgA nephropathy or lupus nephritis. Among 24 patients experiencing a vaccine-associated relapse, 4 (17%) had a change in immunosuppression, and none required a biopsy.

CONCLUSIONS

In a population-level cohort of patients with glomerular disease, a second or third dose of COVID-19 vaccine was associated with higher relative risk but low absolute increased risk of relapse.

Characteristics and Roles of T Follicular Helper Cells in SARS-CoV-2 Vaccine Response

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination is critical to controlling the coronavirus disease 2019 (COVID-19) pandemic. However, a weak response to the vaccine and insufficient persistence of specific antibodies may threaten the global impact of mass vaccination campaigns. This study summarizes the internal factors of the body that affect the effectiveness of the SARS-CoV-2 vaccine. T follicular helper (Tfh) cells support germinal center B cells to produce vaccine-specific immunoglobulins. A reduction in the Tfh cell number and a shift in the subset phenotypes caused by multiple factors may impair the production and persistence of high-affinity antibodies. Besides efficacy differences caused by the different types of vaccines, the factors that affect vaccine effectiveness by intervening in the Tfh cell response also include age-related defects, the polarity of the body microenvironment, repeated immunization, immunodeficiency, and immunosuppressive treatments. Assessing the phenotypic distribution and activation levels of Tfh cell subsets after vaccination is helpful in predicting vaccine responses and may identify potential targets for improving vaccine effectiveness.

Nosocomial COVID-19, a risk illustrated by the first in-hospital transmission of B.1.1.7 variant of SARS-CoV-2 in a French University Hospital

Objectives

In this short report, we describe the first nosocomial spread of B.1.1.7 variant (GR/20I/501Y.V1) in a French hospital, underlining the different aspects of in-hospital transmission of SARS-CoV-2.

Patients and methods

Retrospective study of a SARS-CoV-2 cluster investigation in January 2021. All cases were screened with RT-PCR.

Results

First transmission occurred in a double room with a COVID-19 imported cases, undetected upon admission. Healthcare workers, their relatives and patients’ relatives were screened. Eleven secondary cases were identified within a week, in and out of the hospital (in hospital attack rate: 3.1%). No severe COVID-19 was encountered.

Conclusions

This report highlights several in-hospital chains of transmission involved with COVID-19 with rapid spread.

Identifying Markers of Emerging SARS-CoV-2 Variants in Patients With Secondary Immunodeficiency

Since the end of 2019, the world has been challenged by the coronavirus disease 2019 (COVID-19) pandemic. With COVID-19 cases rising globally, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to evolve, resulting in the emergence of variants of interest (VOI) and of concern (VOC). Of the hundreds of millions infected, immunodeficient patients are one of the vulnerable cohorts that are most susceptible to this virus. These individuals include those with preexisting health conditions and/or those undergoing immunosuppressive treatment (secondary immunodeficiency). In these cases, several researchers have reported chronic infections in the presence of anti-COVID-19 treatments that may potentially lead to the evolution of the virus within the host. Such variations occurred in a variety of viral proteins, including key structural ones involved in pathogenesis such as spike proteins. Tracking and comparing such mutations with those arisen in the general population may provide information about functional sites within the SARS-CoV-2 genome. In this study, we reviewed the current literature regarding the specific features of SARS-CoV-2 evolution in immunocompromised patients and identified recurrent de novo amino acid changes in virus isolates of these patients that can potentially play an important role in SARS-CoV-2 pathogenesis and evolution.

Who Were Hospitalized Deceased Patients from COVID-19 During the First Year of Pandemic? Retrospective Analysis of 1104 Deceased Patients in South of France

Introduction

Following the first year of the COVID-19 pandemic, a complete analysis of the characteristics of the deceased hospitalized patients was performed, to identify factors related to premature mortality and to compare patient profiles according to the epidemic periods.

Methods

Retrospective analysis of 1104 deceased patients in two University Hospitals in South-eastern France, between March 1, 2020 and March 12, 2021 from Hospital’s electronic medical records was performed.

Results

Mean age was 80 years (± 11.1) and 10% of the deceased were younger than 65 years with specific comorbidities, e.g., genetic conditions, metastatic cancer, or massive obesity. Among the three clusters identified, two clusters (75% of deceased patients) include very elderly patients with numerous comorbidities, and differ by their proportion of dependent institutionalized patients. The third cluster is made up of younger patients with fewer but severe comorbidities. Deceased patients’ profiles varied according to the epidemic periods: during the first period (March–June 2020), more patients were institutionalized. The second period (September–December2020) coincided with a higher mortality rate.

Conclusions

This study confirmed that most patients hospitalized and dying from COVID-19 were frail, i.e., elderly and/or highly comorbid and that the small proportion of young patients had severe comorbidities.

Supplementary Information

The online version contains supplementary material available at 10.1007/s44197-022-00039-3.

Mortality trends and lengths of stay among hospitalized COVID-19 patients in Ontario and Québec (Canada): a population-based cohort study of the first three epidemic waves

Background

Epidemics of COVID-19 strained hospital resources. We describe temporal trends in mortality risk and length of stays in hospital and intensive care units (ICUs) among patients with COVID-19 hospitalized through the first three epidemic waves in Canada.

Methods

We used population-based provincial hospitalization data from the epicenters of Canada's epidemics (Ontario and Québec). Adjusted estimates were obtained using marginal standardization of logistic regression models, accounting for patient-level and hospital-level determinants.

Results

Using all hospitalizations from Ontario (N = 26,538) and Québec (N = 23,857), we found that unadjusted in-hospital mortality risks peaked at 31% in the first wave and was lowest at the end of the third wave at 6–7%. This general trend remained after adjustments. The odds of in-hospital mortality in the highest patient load quintile were 1.2-fold (95% CI: 1.0–1.4; Ontario) and 1.6-fold (95% CI: 1.3–1.9; Québec) that of the lowest quintile. Mean hospital and ICU length of stays decreased over time but ICU stays were consistently higher in Ontario than Québec.

Conclusions

In-hospital mortality risks and length of ICU stays declined over time despite changing patient demographics. Continuous population-based monitoring of patient outcomes in an evolving epidemic is necessary for health system preparedness and response.

Nosocomial COVID-19 Infection in a Long-Term Hospital in Spain: Retrospective Observational Study

Background and Objectives. The aim of this study is to compare clinical and epidemiological characteristics and outcomes in patients with versus without nosocomial COVID-19 after exposure to SARS-CoV-2 and to analyze the risk factors for severe outcomes of COVID-19 in a long-term hospital in Spain. Materials and methods. This retrospective, single-center observational study included all inpatients in a long-term hospital during a COVID-19 outbreak from 21 January to 15 March 2021. Results. Of 108 admitted patients, 65 (60.2%) were diagnosed with nosocomial COVID-19 disease (n = 34 women (52.3%), median age 77 years). In the univariable analysis, risk factors associated with nosocomial COVID-19 were dementia (OR 4.98 95% CI 1.58–15.75), dyspnea (OR 5.34 95% CI 1.69–16.82), asthenia (OR 5.10, 95% CI 1.40–18.60) and NECesidades PALiativas (NECPAL) (OR 1.28 95% CI 1.10–1.48). In the multivariable analysis, risk factors independently associated with nosocomial COVID-19 infection were dyspnea (aOR 7.39; 95% CI 1.27–43.11) and NECPAL (aOR 1.25; 95% CI 1.03–1.52). Of the 65 patients diagnosed with nosocomial COVID-19, 29 (44.6%) died, compared to 7/43 (16.2%) non-infected patients (OR 4.14, 95% CI 1.61–10.67). Factors associated with mortality in nosocomial COVID-19 were confusion (aOR 3.83; 95% CI 1.03–14.27) and dyspnea (aOR 7.47; 95% CI 1.87–29.82). The NECPAL tool played an important predictive role in both nosocomial COVID-19 infection and mortality (aOR 1.19, 95% CI: 1.00–1.41). Conclusions. In a long-term hospital, nosocomial COVID-19 main clinical characteristics associated with infection were dyspnea and NECPAL. Mortality was higher in the group with nosocomial COVID-19; risk factors were confusion and dyspnea. The NECPAL tool may help to predict progression and death in COVID-19.

Insights From Early Clinical Trials Assessing Response to mRNA SARS-CoV-2 Vaccination in Immunocompromised Patients

It is critical to protect immunocompromised patients against COVID-19 with effective SARS-CoV-2 vaccination as they have an increased risk of developing severe disease. This is challenging, however, since effective mRNA vaccination requires the successful cooperation of several components of the innate and adaptive immune systems, both of which can be severely affected/deficient in immunocompromised people. In this article, we first review current knowledge on the immunobiology of SARS-COV-2 mRNA vaccination in animal models and in healthy humans. Next, we summarize data from early trials of SARS-COV-2 mRNA vaccination in patients with secondary or primary immunodeficiency. These early clinical trials identified common predictors of lower response to the vaccine such as anti-CD19, anti-CD20 or anti-CD38 therapies, low (naive) CD4+ T-cell counts, genetic or therapeutic Bruton tyrosine kinase deficiency, treatment with antimetabolites, CTLA4 agonists or JAK inhibitors, and vaccination with BNT162b2 versus mRNA1273 vaccine. Finally, we review the first data on third dose mRNA vaccine administration in immunocompromised patients and discuss recent strategies of temporarily holding/pausing immunosuppressive medication during vaccination.

The unseen pandemic: treatment delays and loss to follow-up due to fear of COVID

BACKGROUND

Fear of contracting SARS-CoV-2 has transformed public interaction with healthcare professionals and hospitals alike. In turn, this has resulted in a collateral impact on patients' health across medical and surgical paradigms. Understanding the causative factors of this fear, and tackling it head on, is vital to return to pre-pandemic levels of healthcare.

MAIN BODY

In this editorial, we explore the evidence base behind the fear of healthcare professionals and facilities that has developed during the course of the SARS-CoV-2pandemic. We also reflect on the ways in which these fears have affected the general public. In so doing, we review a recent article from Montalto et al. that has explored fear of SARS-CoV-2 among patients undergoing surgery in Italy.

CONCLUSION

While fear of SARS-CoV-2 is uncommon among surgical patients, there are still those who delay or avoiding seeking medical care due to fear of transmission. Physicians must lead the fight against this fear in a hope to regain the trust of the public.

Evaluation of an Access-Risk-Knowledge (ARK) Platform for Governance of Risk and Change in Complex Socio-Technical Systems

Three key challenges to a whole-system approach to process improvement in health systems are the complexity of socio-technical activity, the capacity to change purposefully, and the consequent capacity to proactively manage and govern the system. The literature on healthcare improvement demonstrates the persistence of these problems. In this project, the Access-Risk-Knowledge (ARK) Platform, which supports the implementation of improvement projects, was deployed across three healthcare organisations to address risk management for the prevention and control of healthcare-associated infections (HCAIs). In each organisation, quality and safety experts initiated an ARK project and participated in a follow-up survey and focus group. The platform was then evaluated against a set of fifteen needs related to complex system transformation. While the results highlighted concerns about the platform's usability, feedback was generally positive regarding its effectiveness and potential value in supporting HCAI risk management. The ARK Platform addresses the majority of identified needs for system transformation; other needs were validated in the trial or are undergoing development. This trial provided a starting point for a knowledge-based solution to enhance organisational governance and develop shared knowledge through a Community of Practice that will contribute to sustaining and generalising that change.