Asymptomatic SARS-CoV-2 Infection in Nursing Homes, Barcelona, Spain, April 2020

The importance of prevalence and pre-test probability on the microbiological diagnosis of SARS-CoV-2: the case of Spain in 2020

OBJECTIVE

The aim of this work was to estimate the conditioned probability for the diagnosis of SARS-CoV-2 infection with reverse transcription polymerase chain reaction (RT-PCR), viral antigen rapid diagnostic tests (Ag-RDT), and antibody detection tests depending on the prevalence in the specific healthcare settings in Spain in 2020, and on the pre-test probability (PTP) according to the clinical situation, age and unknown or close contacts of the patient.

METHODS

Performance parameters of tests were obtained from literature. Prevalence data and PTP were obtained from Spanish sources and a survey, respectively. The post-test probability is the positive predictive value (PPV) when test is positive. For negative result, we also calculated the probability of having the infection (false negatives).

RESULTS

For both RT-PCR and viral Ag-RDT, the lowest PPV values were for the population screenings. This strategy proved to be useful in ruling out infection but generates a high number of false positives. At individual level, both tools provided high PPV (≥ 97%) when the PTP values are over 35%. In seroprevalence studies, though the specificity of IgG alone tests is high, under low seroprevalence, false positives cannot be avoided. Total antibodies tests are useful for diagnosis of COVID-19 in those doubtful cases with RT-PCR or Ag-RDT tests being repeatedly negative.

CONCLUSIONS

The interpretating of results depends not only on the accuracy of the test, but also on the prevalence of the infection in different settings, and the PTP associated to the patient before performing the test.

Transforming the Information System for Research in Primary Care (SIDIAP) in Catalonia to the OMOP Common Data Model and Its Use for COVID-19 Research

Purpose

The primary aim of this work was to convert the Information System for Research in Primary Care (SIDIAP) from Catalonia, Spain, to the Observational Medical Outcomes Partnership (OMOP) Common Data Model (CDM). Our second aim was to provide a descriptive analysis of COVID-19-related outcomes among the general population.

Patients and Methods

We mapped patient-level data from SIDIAP to the OMOP CDM and we performed more than 3,400 data quality checks to assess its readiness for research. We established a general population cohort as of the 1st March 2020 and identified outpatient COVID-19 diagnoses or tested positive for, hospitalised with, admitted to intensive care units (ICU) with, died with, or vaccinated against COVID-19 up to 30th June 2022.

Results

After verifying the high quality of the transformed dataset, we included 5,870,274 individuals in the general population cohort. Of those, 604,472 had either an outpatient COVID-19 diagnosis or positive test result, 58,991 had a hospitalisation, 5,642 had an ICU admission, and 11,233 died with COVID-19. A total of 4,584,515 received a COVID-19 vaccine. People who were hospitalised or died were more commonly older, male, and with more comorbidities. Those admitted to ICU with COVID-19 were generally younger and more often male than those hospitalised and those who died.

Conclusion

We successfully transformed SIDIAP to the OMOP CDM. From this dataset, a general population cohort of 5.9 million individuals was identified and their COVID-19-related outcomes over time were described. The transformed SIDIAP database is a valuable resource that can enable distributed network research in COVID-19 and beyond.

COVID-19 burden and influencing factors in Swiss long-term-care facilities: a cross-sectional analysis of a multicentre observational cohort

OBJECTIVES: To describe the burden of COVID-19 in Swiss long-term care facilities in 2020, to identify its influencing factors, and to assess vaccination rates among residents and healthcare workers at the end of the vaccine campaign in Switzerland in May 2021. DESIGN: Cross-sectional survey. SETTING AND PARTICIPANTS: Long-term care facilities from two Swiss cantons (St. Gallen / Eastern Switzerland and Vaud / Western Switzerland). METHODS: We collected numbers of COVID-19 cases and related deaths and all-cause mortality for 2020, potential risk factors at the institutional level (e.g. size, infection prevention and control measures, and resident characteristics), and vaccination rates among residents and healthcare workers. Univariate and multivariate analyses were used to identify factors associated with resident mortality in 2020. RESULTS: We enrolled 59 long-term care facilities with a median of 46 (interquartile range [IQR]: 33–69) occupied beds. In 2020, the median COVID-19 incidence was 40.2 (IQR: 0–108.6) per 100 occupied beds, with higher rates in VD (49.9%) than in SG (32.5%; p = 0.037). Overall, 22.7% of COVID-19 cases died, of which 24.8% were COVID-19-related deaths. In the univariate analysis, higher resident mortality was associated with COVID-19 rates among residents (p < 0.001) and healthcare workers (p = 0.002) and age (p = 0.013). Lower resident mortality was associated with the proportion of single rooms (p = 0.012), isolation of residents with COVID-19 in single rooms (p = 0.003), symptom screening of healthcare workers (p = 0.031), limiting the number of visits per day (p = 0.004), and pre-scheduling visits (p = 0.037). In the multivariate analysis, higher resident mortality was only associated with age (p = 0.03) and the COVID-19 rate among residents (p = 0.013). Among 2936 residents, 2042 (69.9%) received ≥1 dose of the COVID-19 vaccine before 31 May 2021. Vaccine uptake among healthcare workers was 33.8%. CONCLUSION AND IMPLICATIONS: COVID-19 burden was high but also highly variable in Swiss long-term care facilities. severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among healthcare workers was a modifiable factor associated with increased resident mortality. Symptom screening of healthcare workers appeared to be an effective preventive strategy and should be included in routine infection prevention and control measures. Promoting COVID-19 vaccine uptake among healthcare workers should be a priority in Swiss long-term care facilities.

Clinical impact of the suspension of the ERAS protocol on patients undergoing radical cystectomy during the COVID-19 pandemic

INTRODUCTION

During the beginning of the COVID-19 pandemic in our center, neither prehabilitation nor multimodal rehabilitation could be applied due to the excessive patient load on the health system and to reduce SARS-CoV-2 transmission. The objective of our study was to analyze the evolution, complications, and survival up to one year of patients who underwent radical cystectomy in our hospital from March 1st to May 31st, 2020 (period of the first wave COVID-19 pandemic in Spain). We also compared the results with cystectomized patients outside the pandemic period and with application of the ERAS (Enhanced Recovery After Surgery) protocol.

MATERIAL AND METHODS

Single-center, retrospective cohort study of patients scheduled for radical cystectomy from March 1st, 2020 to May 31st, 2020. They were matched with previously operated patients using a 1:2 propensity matching score. The matching variables were demographic data, preoperative and intraoperative clinical conditions.

RESULTS

A total of 23 radical cystectomies with urinary diversion were performed in the period described. In none of the cases the prehabilitation or the follow-up of our ERAS protocol could be applied, and this was the only difference we found between the 2 groups. Although the minimally invasive approach was more frequent in the pandemic group, the difference was not statistically significant. Three patients were diagnosed with COVID-19 during their admission, presenting severe respiratory complications and high in-hospital mortality. Apart from respiratory complications secondary to SARS-CoV-2, we also found statistically significant differences in other postoperative complications. The hospital stay increased by 3 days in the pandemic group.

CONCLUSIONS

Patients who underwent radical cystectomy at our center during the first wave of the COVID-19 pandemic had a higher number and severity of respiratory and non-respiratory complications. Discontinuation of the ERAS protocol was the main difference in treatment between groups.

[CLINICAL IMPACT OF THE SUSPENSION OF THE ERAS PROTOCOL ON PATIENTS UNDERGOING RADICAL CYSTECTOMY DURING THE COVID-19 PANDEMIC.]

INTRODUCTION

During the beginning of the COVID-19 pandemic in our center, neither prehabilitation nor multimodal rehabilitation could be applied due to the excessive patient load on the health system and to reduce SARS-CoV-2 transmission. The objective of our study was to analyze the evolution, complications, and survival up to one year of patients who underwent radical cystectomy in our hospital from March 1st to May 31st, 2020 (period of the first wave COVID-19 pandemic in Spain). We also compared the results with cystectomized patients outside the pandemic period and with application of the ERAS (Enhanced Recovery After Surgery) protocol.

MATERIAL AND METHODS

Single-center, retrospective cohort study of patients scheduled for radical cystectomy from March 1st,2020 to May 31st, 2020. They were matched with previously operated patients using a 1:2 propensity matching score. The matching variables were demographic data, preoperative and intraoperative clinical conditions.

RESULTS

A total of 23 radical cystectomies with urinary diversion were performed in the period described. In none of the cases the prehabilitation or the follow-up of our ERAS protocol could be applied, and this was the only difference we found between the 2 groups. Although the minimally invasive approach was more frequent in the pandemic group, the difference was not statistically significant. Three patients were diagnosed with COVID-19 during their admission, presenting severe respiratory complications and high in-hospital mortality. Apart from respiratory complications secondary to SARS-CoV-2, we also found statistically significant differences in other postoperative complications. The hospital stay increased by 3 days in the pandemic group.

CONCLUSIONS

Patients who underwent radical cystectomy at our center during the first wave of the COVID-19 pandemic had a higher number and severity of respiratory and non-respiratory complications. Discontinuation of the ERAS protocol was the main difference in treatment between groups.

Impact of the COVID-19 pandemic and corresponding control measures on long-term care facilities: a systematic review and meta-analysis

BACKGROUND

Long-term care facilities (LTCFs) were high-risk settings for COVID-19 outbreaks.

OBJECTIVE

To assess the impacts of the COVID-19 pandemic on LTCFs, including rates of infection, hospitalisation, case fatality, and mortality, and to determine the association between control measures and SARS-CoV-2 infection rates in residents and staff.

METHOD

We conducted a systematic search of six databases for articles published between December 2019 and 5 November 2021, and performed meta-analyses and subgroup analyses to identify the impact of COVID-19 on LTCFs and the association between control measures and infection rate.

RESULTS

We included 108 studies from 19 countries. These studies included 1,902,044 residents and 255,498 staff from 81,572 LTCFs, among whom 296,024 residents and 36,807 staff were confirmed SARS-CoV-2 positive. The pooled infection rate was 32.63% (95%CI: 30.29 ~ 34.96%) for residents, whereas it was 10.33% (95%CI: 9.46 ~ 11.21%) for staff. In LTCFs that cancelled visits, new patient admissions, communal dining and group activities, and vaccinations, infection rates in residents and staff were lower than the global rate. We reported the residents' hospitalisation rate to be 29.09% (95%CI: 25.73 ~ 32.46%), with a case-fatality rate of 22.71% (95%CI: 21.31 ~ 24.11%) and mortality rate of 15.81% (95%CI: 14.32 ~ 17.30%). Significant publication biases were observed in the residents' case-fatality rate and the staff infection rate, but not in the infection, hospitalisation, or mortality rate of residents.

CONCLUSION

SARS-CoV-2 infection rates would be very high among LTCF residents and staff without appropriate control measures. Cancelling visits, communal dining and group activities, restricting new admissions, and increasing vaccination would significantly reduce the infection rates.

Evaluation of symptomatology and viral load among residents and healthcare staff in long-term care facilities: A coronavirus disease 2019 retrospective case-cohort study

Objectives

We evaluated COVID-19 symptoms, case fatality rate (CFR), and viral load among all Long-Term Care Facility (LTCF) residents and staff in South Limburg, the Netherlands (February 2020-June 2020, wildtype SARS-CoV-2 Wuhan strain).

Methods

Patient information was gathered via regular channels used to notify the public health services. Ct-values were obtained from the Maastricht University Medical Centre laboratory. Logistic regression analyses were performed to assess associations between COVID-19, symptoms, CFR, and viral load.

Results

Of 1,457 staff and 1,540 residents, 35.1% and 45.2% tested positive for COVID-19. Symptoms associated with COVID-19 for female staff were fever, cough, muscle ache and loss of taste and smell. Associated symptoms for men were cough, and loss of taste and smell. Associated symptoms for residents were subfebrility, fatigue, and fever for male residents only. LTCF residents had a higher mean viral load compared to staff. Male residents had a higher CFR (35.8%) compared to women (22.5%). Female residents with Ct-values 31 or less had increased odds of mortality.

Conclusions

Subfebrility and fatigue seem to be associated with COVID-19 in LTCF residents. Therefore, physicians should also consider testing residents who (only) show aspecific symptoms whenever available resources prohibit testing of all residents. Viral load was higher in residents compared to staff, and higher in male residents compared to female residents. All COVID-19 positive male residents, as well as female residents with a medium to high viral load (Ct-values 31 or lower) should be monitored closely, as these groups have an overall increased risk of mortality.

Best practice approaches to outpatient management of people living with Parkinson's disease during the COVID-19 pandemic

The prevalence of Parkinson's disease (PD) is rising, rendering it one of the most common neurodegenerative diseases. Treatment and monitoring of patients require regular specialized in- and outpatient care. Patients with PD are more likely to have a complicated disease course if they become infected with severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2). Regular in-hospital appointments place these patients at risk of exposure to SARS-CoV-2 due to travel and contact with other patients and staff. However, guidelines for the management of outpatients with PD during times of increased risk of infection are currently lacking. These are urgently needed to conduct risk-benefit evaluations to recommend the best medical treatment. This article discusses best practice approaches based on the current literature, as suggested by the multidisciplinary Network of University Medicine (NUM) in Germany. These include measures such as mask-wearing, hand hygiene, social distancing measures, and appropriate testing strategies in outpatient settings, which can minimize the risk of exposure. Furthermore, the urgency of appointments should be considered. Visits of low urgency may be conducted by general practitioners or via telemedicine consultations, whereas in-person presentation is required in case of moderate and high urgency visits. Classification of urgency should be carried out by skilled medical staff, and telemedicine (telephone or video consultations) may be a useful tool in this situation. The currently approved vaccines against SARS-CoV-2 are safe and effective for patients with PD and play a key role in minimizing infection risk for patients with PD.

Managing the Impact of COVID-19 in Nursing Homes and Long-Term Care Facilities: An Update

Older adults in nursing homes are at greatest risk of morbidity and mortality from SARS-CoV-2 infection. Nursing home residents constituted one-third to more than half of all deaths during the early waves of the COVID-19 pandemic. Following this, widespread adaptation of infection prevention and control measures and the supply and use of personal protective equipment resulted in a significant decrease in nursing home infections and deaths. For nursing homes, the most important determinant of experiencing a SARS-CoV-2 outbreak in the first instance appears to be community-transmission levels (particularly with variants of concern), although nursing home size and quality, for-profit status, and sociodemographic characteristics are also important. Use of visitation bans, imposed to reduce the impact of COVID-19 on residents, must be delicately balanced against their impact on resident, friend or family, and staff well-being. The successful rollout of primary vaccination has resulted in a sharp decrease in morbidity and mortality from SARS-CoV-2 in nursing homes. However, emerging evidence suggests that vaccine efficacy may wane over time, and the use of a third or additional vaccine "booster" doses in nursing home residents restores protection afforded by primary vaccination. Ongoing monitoring of vaccine efficacy in terms of infection, morbidity, and mortality is crucial in this vulnerable group in informing ongoing SARS-CoV-2 vaccine boosting strategies. Here, we detail the impact of SARS-CoV-2 on nursing home residents and discuss important considerations in the management of nursing home SARS-CoV-2 outbreaks. We additionally examine the use of testing strategies, nonpharmacologic outbreak control measures and vaccination strategies in this cohort. Finally, the impact of SARS-CoV-2 on the sector is reflected on as we emphasize the need for adoption of universal standards of medical care and integration with wider public health infrastructure in nursing homes in order to provide a safe and effective long-term care sector.

Nosocomial COVID-19. Prospective study in a referral hospital

BACKGROUND AND OBJECTIVE

The objective was to describe the clinical characteristics and prognosis of patients with nosocomial SARS-CoV-2 infection.

METHODS

An observational and prospective study was performed in a referral hospital. We included all adult patients diagnosed with nosocomial SARS-CoV-2 infection in October 2020. Nosocomial infection was defined as a negative PCR for SARS-CoV-2 on admission and a positive PCR after 7 days of hospitalization.

RESULTS

We included 66 cases of nosocomial SARS-CoV-2 infection: 39 (59%) men, median age at diagnosis was 74.5 years (IQR 56.8-83.1) and median Charlson comorbidity index was 3 points (IQR 1-5). Twenty-seven (41%) developed pneumonia and 13 (20%) died during admission. Mortality at 28 days was 33% (22 patients). Mortality at 28 days in the 242 patients with community-acquired SARS-CoV-2 infection who were hospitalized during the same period was 10%.

CONCLUSIONS

Preventive measures and early detection of nosocomial outbreaks of COVID-19 should be prioritized to minimize the negative impact of this infection.

The role of routine SARS-CoV-2 screening of healthcare-workers in acute care hospitals in 2020: a systematic review and meta-analysis

BACKGROUND

Healthcare workers (HCW) are at increased risk of infection with SARS-CoV-2. Vulnerable patient populations in particular must be protected, and clinics should not become transmission hotspots to avoid delaying medical treatments independent of COVID. Because asymptomatic transmission has been described, routine screening of asymptomatic HCW would potentially be able to interrupt chains of infection through early detection.

METHODS

A systematic search was conducted in the Cochrane COVID-19 Study Register, Web of Science and WHO COVID-19 Global literature on coronavirus with regard to non-incident related testing of healthcare workers using polymerase chain reaction on May 4th 2021. Studies since January 2020 were included. An assessment of risk of bias and representativeness was performed.

RESULTS

The search identified 39 studies with heterogeneous designs. Data collection of the included studies took place from January to August 2020. The studies were conducted worldwide and the sample size of the included HCW ranged from 70 to 9449 participants. In total, 1000 of 51,700 (1.9%) asymptomatic HCW were tested positive for SARS-CoV-2 using PCR testing. The proportion of positive test results ranged between 0 and 14.3%. No study reported on HCW-screening related reductions in infected person-days.

DISCUSSION AND CONCLUSIONS

The heterogeneous proportions might be explained by different regional incidences, lock-downs, and pre-analytical pitfalls that reduce the sensitivity of the nasopharyngeal swab. The very high prevalence in some studies indicates that screening HCW for SARS-CoV-2 may be important particularly in geographical regions and pandemic periods with a high-incidence. With low numbers and an increasing rate of vaccinated HCW, a strict cost-benefit consideration must be made, especially in times of low incidences. Since we found no studies that reported on HCW-screening related reductions in infected person-days, re-evaluation should be done when these are available.

The Impact of Long-Term Care Home Ownership and Administration Type on All-Cause Mortality from March to April 2020 in Madrid, Spain

Our aim is to assess whether long-term care home (LTCH) ownership and administration type were associated with all-cause mortality in 470 LTCHs in the Community of Madrid (Spain) during March and April 2020, the first two months of the COVID-19 pandemic. There are eight categories of LTCH type, including various combinations of ownership type (for-profit, nonprofit, and public) and administration type (completely private, private with places rented by the public sector, administrative management by procurement, and completely public). Multilevel regression was used to examine the association between mortality and LTCH type, adjusting for LTCH size, the spread of the COVID-19 infection, and the referral hospital. There were 9468 deaths, a mortality rate of 18.3%. Public and private LTCHs had lower mortality than LTCHs under public-private partnership (PPP) agreements. In the fully adjusted model, mortality was 7.4% (95% CI, 3.1-11.7%) in totally public LTCHs compared with 21.9% (95% CI, 17.4-26.4%) in LTCHs which were publicly owned with administrative management by procurement. These results are a testimony to the fatal consequences that pre-pandemic public-private partnerships in long-term residential care led to during the first months of the COVID-19 pandemic in the Community of Madrid, Spain.

Pre-operative prevalence of asymptomatic carriers of COVID-19 in hospitals in Catalonia during the first wave after the resumption of surgical activity

Introduction

The COVID-19 pandemic led to the cancellation of non-essential surgical procedures in March 2020. With the resumption of surgical activity, patients undergoing surgery were one of the first population groups to be systematically tested for PCR. The aim of this study was to determine the prevalence of asymptomatic SARS-CoV-2 carriers after the resumption of non-essential surgical activity.

Methods

Retrospective multicenter observational study of patients scheduled for surgery or undergoing emergency surgery in Catalonia between 20 April and 31 May 2020. The microbiological results of preoperative PCR tests and clinical records were reviewed, and an epidemiological survey was conducted on patients with positive PCR for SARS-CoV-2.

Results

A total of 10,838 patients scheduled for surgery or who underwent emergency surgery were screened for COVID-19. One hundred and eighteen patients (1.09%) were positive for SARS-CoV-2 in the 72 h prior to surgery. The prevalence of asymptomatic carriers was 0.7% (IC95%: 0.6%–0.9%). The first week of the study presented the highest prevalence of asymptomatic carriers [1.9% (CI95%:1.1%–3.2%)].

Conclusions

The low levels of asymptomatic carriers of COVID-19 infection obtained in the surgical population of hospitals in Catalonia after the resumption of surgical activity, shows that most patients were able to undergo surgical procedures without the risks of COVID-19 associated complications in the perioperative period.

Incidence, Mortality, and Risk Factors of COVID-19 in Nursing Homes

During the period from March 2020 to January 2021, we performed an analysis of incidence, mortality, and risk factors of COVID-19 in nursing homes (NHs) in two health departments (HDs) of Castellon (Spain) 2021 through epidemiological surveillance and an ecological design. Laboratory-confirmed COVID-19 cases, cumulative incidence rate (CIR), and mortality rate (MR) of 27 NHs were collected. Information of residents, staff, and facilities was obtained by questionnaire. Multilevel Poisson regression models were applied. All NHs in the HDs participated with 2229 residents (median: 83 years old, 67.3% women) and 1666 staff. Among residents, 815 cases (CIR: 34.8 per 100) and 202 deaths (MR: 8.7 per 100, case fatality 21.0%) were reported and, among staff, 296 cases (CIR: 19.2 per 100) without deaths. Residents' CIR and MR increased with staff CIR, age of the building, residents/staff ratios, occupancy rate, and crowding index; CIR increased with private NH ownership, large NH size, large urban area, and the percentage of women residents; and MR was associated with residents' severe disabilities. In conclusion, several risk factors of COVID-19 incidence and mortality can be prevented by improving infection and quality controls, ameliorating residents/staff ratios, improving structural facilities, and increasing NH public ownership to avoid new outbreaks.

CM, A. BG, F. VS, A. SF, V. OQ, A. SC, on behalf of the COVID-19 Group of the Spanish Society of Primary Care Physicians (SEMERGEN). Analysis of case fatality rate of SARS-CoV-2 infection in the Spanish Autonomous Communities between March and May 2020

OBJECTIVE

The Spanish health system is made up of seventeen regional health systems. Through the official reporting systems, some inconsistencies and differences in case fatality rates between Autonomous Communities (CC.AA.) have been observed. Therefore the objective of this paper is to compare COVID-19 case fatality rates across the Spanish CC.AA.

MATERIAL AND METHODS

Observational descriptive study. The COVID-19 case fatality rate (CFR) was estimated according to the official records (CFR-PCR+), the daily mortality monitory system (MoMo) record (CFR-Mo), and the seroprevalence study ENE-COVID-19 (Estudio Nacional de sero Epidemiologia Covid-19) according to sex, age group and CC.AA. between March and June 2020. The main objective is to detect whether there are any differences in CFR between Spanish Regions using two different register systems, i. e., the official register of the Ministry of Health and the MoMo.

RESULTS

Overall, the CFR-Mo was higher than the CFR-PCR+, 1.59% vs 0.98%. The differences in case fatality rate between both methods were significantly higher in Castilla La Mancha, Castilla y León, Cataluña, and Madrid. The difference between both methods was higher in persons over 74 years of age (CFR-PCR+ 7.5% vs 13.0% for the CFR-Mo) but without statistical significance. There was no correlation of the estimated prevalence of infection with CFR-PCR+, but there was with CFR-Mo (R2 = 0.33). Andalucía presented a SCFR below 1 with both methods, and Asturias had a SCFR higher than 1. Cataluña and Castilla La Mancha presented a SCFR greater than 1 in any scenario of SARS-CoV-2 infection calculated with SCFR-Mo.

CONCLUSIONS

The PCR+ case fatality rate underestimates the case fatality rate of the SARS-CoV- 2 virus pandemic. It is therefore preferable to consider the MoMo case fatality rate. Significant differences have been observed in the information and registration systems and in the severity of the pandemic between the Spanish CC.AA. Although the infection prevalence correlates with case fatality rate, other factors such as age, comorbidities, and the policies adopted to address the pandemic can explain the differences observed between CC.AA.

Nursing homes during the COVID-19 pandemic: a scoping review of challenges and responses

INTRODUCTION

COVID-19 has caused unprecedented challenges in nursing homes. In this scoping review, we aimed to describe factors that contributed to the spread and mortality of COVID-19 in nursing homes and provide an overview of responses that were implemented to try to overcome such challenges.

METHODS

The MeSH terms "Nursing homes" and "COVID-19" were searched in MEDLINE Ovid, and English language articles were retrieved that were published between 1 March 2020 and 31 January 2021. Article titles and abstracts were screened by two reviewers, and the results of included articles were grouped by themes.

RESULTS

The search retrieved 348 articles, of which 76 were included in the thematic review. 8 articles related to COVID-19 disease characteristics (e.g. asymptomatic transmission), 24 to resident-related factors (e.g. comorbidities, nutrition, cognition), 13 to facility characteristics (e.g. physical space, occupancy, for-profit status), 21 to staffing (e.g. staffing levels, staff-to-resident ratio, staff multi-employment), and 10 to external factors (e.g. availability of personal protective equipment, prevailing health and social care policies). In terms of responses, identified themes included widespread testing, isolation and cohorting of residents, staff protection and support, promotion of residents' well-being, and technological innovations.

CONCLUSION

COVID-19 exerted severe challenges on the nursing home population and its staff. Both internal and external factors predisposed nursing homes to an increased propensity of spread. Numerous strategies were employed to attempt to mitigate the negative impacts. Substantial learning occurred that may not only aid future pandemic preparedness but improve quality of care for nursing home residents at all times.

Comparing the first and second waves of COVID-19 in a tertiary university hospital in Barcelona

BACKGROUND

Hospitals have constituted the limiting resource of the healthcare systems for the management of the COVID-19 pandemic. As the pandemic progressed, knowledge of the disease improved, and healthcare systems were expected to be more adapted to provide a more efficient response. The objective of this research was to compare the flow of COVID-19 patients in emergency rooms and hospital wards, between the pandemic's first and second waves at the University Hospital of Vall d'Hebron (Barcelona, Spain), and to compare the profiles, severity and mortality of COVID-19 patients between the two waves.

METHODS

A retrospective observational analysis of COVID-19 patients attending the hospital from February 24 to April 26, 2020 (first wave) and from July 24, 2020, to May 18, 2021 (second wave) was carried out. We analysed the data of the electronic medical records on patient demographics, comorbidity, severity, and mortality.

RESULTS

The daily number of COVID-19 patients entering the emergency rooms (ER) dropped by 65% during the second wave compared to the first wave. During the second wave, patients entering the ER were significantly younger (61 against 63 years old p<0.001) and less severely affected (39% against 48% with a triage level of resuscitation or emergency; p<0.001). ER mortality declined during the second wave (1% against 2%; p<0.000). The daily number of hospitalised COVID-19 patients dropped by 75% during the second wave. Those hospitalised during the second wave were more severely affected (20% against 10%; p<0.001) and were referred to the intensive care unit (ICU) more frequently (21% against 15%; p<0.001). Inpatient mortality showed no significant difference between the two waves.

CONCLUSIONS

Changes in the flow, severity and mortality of COVID-19 patients entering this tertiary hospital during the two waves may reflect a better adaptation of the health care system and the improvement of knowledge on the disease.

SARS-CoV-2 and Wisconsin Nursing Homes: Temporal Dynamics During the COVID-19 Pandemic

OBJECTIVES

Evidence suggests that quality, location, and staffing levels may be associated with COVID-19 incidence in nursing homes. However, it is unknown if these relationships remain constant over time. We describe incidence rates of COVID-19 across Wisconsin nursing homes while examining factors associated with their trajectory during 5 months of the pandemic.

DESIGN

Retrospective cohort study.

SETTING/PARTICIPANTS

Wisconsin nursing homes.

METHODS

Publicly available data from June 1, 2020, to October 31, 2020, were obtained. These included facility size, staffing, 5-star Medicare rating score, and components. Nursing home characteristics were compared using Pearson chi-square and Kruskal-Wallis tests. Multiple linear regressions were used to evaluate the effect of rurality on COVID-19.

RESULTS

There were a total of 2459 COVID-19 cases across 246 Wisconsin nursing homes. Number of beds (P < .001), average count of residents per day (P < .001), and governmental ownership (P = .014) were associated with a higher number of COVID-19 cases. Temporal analysis showed that the highest incidence rates of COVID-19 were observed in October 2020 (30.33 cases per 10,000 nursing home occupied-bed days, respectively). Urban nursing homes experienced higher incidence rates until September 2020; then incidence rates among rural nursing homes surged. In the first half of the study period, nursing homes with lower-quality scores (1-3 stars) had higher COVID-19 incidence rates. However, since August 2020, incidence was highest among nursing homes with higher-quality scores (4 or 5 stars). Multivariate analysis indicated that over time rural location was associated with increased incidence of COVID-19 (β = 0.05, P = .03).

CONCLUSIONS AND IMPLICATIONS

Higher COVID-19 incidence rates were first observed in large, urban nursing homes with low-quality rating. By October 2020, the disease had spread to rural and smaller nursing homes and those with higher-quality ratings, suggesting that community transmission of SARS-CoV-2 may have propelled its spread.

Epidemiology of COVID-19 among health personnel in long-term care centers in Seville

Background

Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2 infection, spreads swiftly in nursing homes and assisted living facilities, leading to a high degree of lethality. The data generated by an epidemiological surveillance program allow for obtaining valid information on the diseases’ epidemiology and possible prevention methods.

Objective

This work aims to analyze COVID-19 epidemiology among healthcare staff based in the Seville healthcare district (Spain) and evaluate its role in outbreaks in nursing homes.

Methods

This is an observational, descriptive study of 88 assisted living facilities located in the city of Seville from March 1 to May 23, 2020. Data were obtained via epidemiological surveys on staff at centers where there were outbreaks (n = 732 in 14 nursing homes). The cumulative incidence, epidemic curves, sociodemographic and clinical characteristics, and delays in isolation and notification of cases were calculated. For the statistical analysis, measures of central tendency and dispersion were used as well as confidence intervals and statistical hypothesis tests.

Results

There were 124 cases in staff members (cumulative incidence 16.9%), 79.0% of which were in women. The majority presented with mild symptoms (87.1%). The most common symptoms were fever (31.5%) and cough (49.2%). The median number of days from onset of symptoms to isolation was three.

Conclusions

A high incidence in nursing home staff along with delays in isolation were observed, which could affect the dynamics of transmission in outbreaks. It is necessary to review disease identification and isolation practices among staff as well as emphasize rapid implementation of prevention measures.

A rapid systematic review of measures to protect older people in long-term care facilities from COVID-19

OBJECTIVES

The global COVID-19 pandemic produced large-scale health and economic complications. Older people and those with comorbidities are particularly vulnerable to this virus, with nursing homes and long term care facilities (LTCF) experiencing significant morbidity and mortality associated with COVID-19 outbreaks. The aim of this rapid systematic review was to investigate measures implemented in LTCF to reduce transmission of COVID-19 and their effect on morbidity and mortality of residents, staff and visitors.

SETTING

Long-term care facilities.

PARTICIPANTS

Residents, staff and visitors of facilities.

PRIMARY AND SECONDARY OUTCOME MEASURES

Databases (PubMed, EMBASE, CINAHL, Cochrane Databases and repositories and MedRXiv prepublished database) were systematically searched from inception to 27 July 2020 to identify studies reporting assessment of interventions to reduce transmission of COVID-19 in nursing homes among residents, staff or visitors. Outcome measures include facility characteristics, morbidity data, case fatalities and transmission rates. Due to study quality and heterogeneity, no meta-analysis was conducted.

RESULTS

The search yielded 1414 articles, with 38 studies included. Reported interventions include mass testing, use of personal protective equipment, symptom screening, visitor restrictions, hand hygiene and droplet/contact precautions, and resident cohorting. Prevalence rates ranged from 1.2% to 85.4% in residents and 0.6% to 62.6% in staff. Mortality rates ranged from 5.3% to 55.3% in residents.

CONCLUSIONS

Novel evidence in this review details the impact of facility size, availability of staff and practices of operating between multiple facilities, and for-profit status of facilities as factors contributing to the size and number of COVID-19 outbreaks. No causative relationships can be determined; however, this review provides evidence of interventions that reduce transmission of COVID-19 in LTCF.

PROSPERO REGISTRATION NUMBER

CRD42020191569.

Pooled testing for SARS-CoV-2, options for efficiency at scale

Widescale testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is recognized as a key element of surveillance and outbreak control in the coronavirus disease 2019 (COVID-19) pandemic. The practical challenges, however, have often led to testing only symptomatic individuals and their close contacts. As many countries plan for a cautious relaxation of social restrictions, more effective approaches for widescale testing are increasingly important. Early in the COVID-19 pandemic, laboratories in several countries demonstrated the feasibility of detecting SARS-CoV-2 infection by pooled testing, which combines the specimens from several individuals. Since no further testing is needed for individuals in a negative pool, there is potential for greater efficiency of testing. Despite validations of the accuracy of the results and the efficiency in testing specific groups, the benefits of pooling are less acknowledged as a population surveillance strategy that can detect new disease outbreaks without posing restrictions on entire societies. Pooling specimens from natural clusters, such as school classes, sports teams, workplace colleagues and other social networks, would enable timely and cost-effective widescale testing for SARS-CoV-2. The initial result would be readily translatable into action in terms of quarantine and isolation policies. Clusters of uninfected individuals would be quickly identified and immediate local lockdown of positive clusters would be the appropriate and sufficient action while retesting those individuals. By adapting to the social networks of a population, pooled testing offers a cost-efficient surveillance system that is synchronized with quarantine policies that are rational, risk-based and equitable.

Protecting Nursing Homes and Long-Term Care Facilities From COVID-19: A Rapid Review of International Evidence

OBJECTIVES

The COVID-19 pandemic has highlighted the extreme vulnerability of older people and other individuals who reside in long-term care, creating an urgent need for evidence-based policy that can adequately protect these community members. This study aimed to provide synthesized evidence to support policy decision making.

DESIGN

Rapid narrative review investigating strategies that have prevented or mitigated SARS-CoV-2 transmission in long-term care.

SETTING AND PARTICIPANTS

Residents and staff in care settings such as nursing homes and long-term care facilities.

METHODS

PubMed/Medline, Cochrane Library, and Scopus were systematically searched, with studies describing potentially effective strategies included. Studies were excluded if they did not report empirical evidence (eg, commentaries and consensus guidelines). Study quality was appraised on the basis of study design; data were extracted from published reports and synthesized narratively using tabulated data extracts and summary tables.

RESULTS

Searches yielded 713 articles; 80 papers describing 77 studies were included. Most studies were observational, with no randomized controlled trials identified. Intervention studies provided strong support for widespread surveillance, early identification and response, and rigorous infection prevention and control measures. Symptom- or temperature-based screening and single point-prevalence testing were found to be ineffective, and serial universal testing of residents and staff was considered crucial. Attention to ventilation and environmental management, digital health applications, and acute sector support were also considered beneficial although evidence for effectiveness was lacking. In observational studies, staff represented substantial transmission risk and workforce management strategies were important components of pandemic response. Higher-performing facilities with less crowding and higher nurse staffing ratios had reduced transmission rates. Outbreak investigations suggested that facility-level leadership, intersectoral collaboration, and policy that facilitated access to critical resources were all significant enablers of success.

CONCLUSIONS AND IMPLICATIONS

High-quality evidence of effectiveness in protecting LTCFs from COVID-19 was limited at the time of this study, though it continues to emerge. Despite widespread COVID-19 vaccination programs in many countries, continuing prevention and mitigation measures may be required to protect vulnerable long-term care residents from COVID-19 and other infectious diseases. This rapid review summarizes current evidence regarding strategies that may be effective.

Risk Factors for COVID-19 Morbidity and Mortality in Institutionalised Elderly People

BACKGROUND

SARS-CoV-2 has caused a high mortality in institutionalised individuals. There are very few studies on the involvement and the real impact of COVID-19 in nursing homes. This study analysed factors related to morbidity and mortality of COVID-19 in institutionalised elderly people.

METHODS

This cohort study included 842 individuals from 12 nursing homes in Sant Cugat del Vallès (Spain) from 15 March to 15 May 2020. We evaluated individual factors (demographic, dependence, clinical, and therapeutic) and those related to the nursing homes (size and staff) associated with infection and mortality by SARS-CoV-2. Infection was diagnosed by molecular biology test.

RESULTS

Of the 842 residents included in the analysis, 784 underwent a Polymerase Chain Reaction (PCR) test; 74.2% were women, the mean age was 87.1 years, and 11.1% died. The PCR test was positive in 44%. A total of 33.4% of the residents presented symptoms compatible with COVID-19 and of these, 80.9% were PCR-positive for SARS-CoV-2. Infection by SARS-CoV-2 among residents was associated with the rate of staff infected in the homes. Mortality by SARS-CoV-2 was related to male sex and a greater grade of dependence measured with the Barthel index.

CONCLUSIONS

SARS-Cov-2 infection in institutionalised people is associated with the infection rate in nursing home workers and mortality by SARS-Cov-2 with sex and greater dependency according to the Barthel index. Adequate management of nursing home staff and special attention to measures of infection control, especially of individuals with greater dependence, are keys for successful management of future pandemic situations.

[COVID-19 deaths among residents of inpatient nursing homes in Munich-causes and places of death]

INTRODUCTION

The new infectious disease COVID-19 first appeared in China in December 2019. So far, a systematic evaluation of death certificates of COVID-19-associated deaths of residents in inpatient nursing homes has not been presented.

METHODS

Death certificates of all deaths in Munich in the death period from 1 March to 31 July 2020 were analyzed. Inclusion criteria were the presence of "Corona, COVID-19, SARS-CoV-2" on the death certificates. Standardized, anonymized data entry was performed. The collected data were analyzed descriptively.

RESULTS

During the study period, a total of 5840 persons died, 281 (4.8%) of whom died of confirmed COVID-19 disease. Of those, 72 deaths involved residents of Munich nursing facilities. The most frequent causes of death were respiratory insufficiency (54 cases) and multiple organ failure (9 cases). On the death certificates, an average of two preexisting diseases had been reported; the average age at death was 88 years. All deaths of nursing home residents occurred in association with nosocomial COVID-19 outbreaks, which affected one-third of the facilities. The vast majority of these homes did not have a COVID-19 hygiene plan in place at the time.

DISCUSSION

One quarter of all COVID-19 deaths in Munich occurred in the context of nosocomial outbreaks in elderly, chronically ill residents of nursing facilities. Evidence of inadequate risk assessment and inadequate hygiene management emerged. In the opinion of the authors, the appropriate structures for adequate hygiene management must be created and a hygiene regulation must be issued in which the tasks and responsibilities of the facility operators are defined.

Nosocomial COVID-19. Prospective study in a referral hospital

Antecedentes y Objetivo

El objetivo fue describir las características clínicas y el pronóstico de los pacientes con infección nosocomial por SARS-CoV-2.

Métodos

Se realizó un estudio observacional y prospectivo en un hospital de referencia. Se incluyeron todos los pacientes adultos diagnosticados de infección por SARS-CoV-2 nosocomial en octubre de 2020, definida como una PCR para SARS-CoV-2 negativa al ingreso y positiva a partir de los siete días de hospitalización.

Resultados

Se diagnosticaron 66 casos de infección por SARS-CoV-2 nosocomial: 39 (59%) hombres, edad mediana al diagnóstico de 74,5 años (RIC 56,8-83,1) y mediana del índice de comorbilidad de Charlson de 3 puntos (RIC 1-5). Veintisiete (41%) presentaron neumonía y 13 (20%) fallecieron durante el ingreso. La mortalidad a los 28 días fue del 33% (22 pacientes). La mortalidad a los 28 días en los 242 pacientes con infección por SARS-CoV-2 adquirida en la comunidad y hospitalizados durante el mismo periodo fue del 10%.

Conclusiones

Se deben extremar las medidas de prevención y detección precoz de brotes nosocomiales de COVID-19 para minimizar el impacto negativo de esta infección.

Clinical characteristics of COVID-19 in older adults. A retrospective study in long-term nursing homes in Catalonia

The natural history of COVID-19 and predictors of mortality in older adults need to be investigated to inform clinical operations and healthcare policy planning. A retrospective study took place in 80 long-term nursing homes in Catalonia, Spain collecting data from March 1st to May 31st, 2020. Demographic and clinical data from 2,092 RT-PCR confirmed cases of SARS-CoV-2 infection were registered, including structural characteristics of the facilities. Descriptive statistics to describe the demographic, clinical, and molecular characteristics of our sample were prepared, both overall and by their symptomatology was performed and an analysis of statistically significant bivariate differences and constructions of a logistic regression model were carried out to assess the relationship between variables. The incidence of the infection was 28%. 71% of the residents showed symptoms. Five major symptoms included: fever, dyspnea, dry cough, asthenia and diarrhea. Fever and dyspnea were by far the most frequent (50% and 28%, respectively). The presentation was predominantly acute and symptomatology persisted from days to weeks (mean 9.1 days, SD = 10,9). 16% of residents had confirmed pneumonia and 22% required hospitalization. The accumulated mortality rate was 21.75% (86% concentrated during the first 28 days at onset). A multivariate logistic regression analysis showed a positive predictive value for mortality for some variables such as age, pneumonia, fever, dyspnea, stupor refusal to oral intake and dementia (p<0.01 for all variables). Results suggest that density in the nursing homes did not account for differences in the incidence of the infection within the facilities. This study provides insights into the natural history of the disease in older adults with high dependency living in long-term nursing homes during the first pandemic wave of March-May 2020 in the region of Catalonia, and suggests that some comorbidities and symptoms have a strong predictive value for mortality.

[Epidemiology of COVID-19 among health personnel in long-term care centers in Seville]

Antecedentes

La infección por coronavirus SARS-CoV-2 se transmite rápidamente en residencias de mayores y centros sociosanitarios, provocando una elevada letalidad. Los datos generados por el programa de vigilancia epidemiológica permiten información válida sobre la epidemiología del problema y las posibilidades de prevención.

Objetivo

Analizar la epidemiología de la infección por COVID-19 entre los profesionales sociosanitarios del Distrito Sanitario Sevilla y su papel en la evolución de los brotes en las residencias de mayores.

Metodología

Estudio sobre 88 centros sociosanitarios de la ciudad de Sevilla en el período del 1 marzo al 23 mayo de 2020, partiendo de las encuestas epidemiológicas en casos del personal donde hubo brotes (n = 732 en 14 residencias). Se calcularon incidencias acumuladas, curvas epidémicas, características sociodemográficas y clínicas, y demoras en el aislamiento y notificación de los casos. Para el análisis estadístico se emplearon medidas de tendencia central y de dispersión, así como intervalos de confianza y pruebas de contraste de hipótesis.

Resultados

Se produjeron 124 casos en trabajadores (tasa de ataque 16,9%), 79,0% en mujeres. La gran mayoría presentaron síntomas leves (87,1%). Los comunes fueron fiebre (31,5%) y tos (49,2%). La mediana de días desde el inicio de los síntomas hasta el aislamiento fue 3 días.

Conclusiones

Se objetiva una elevada incidencia en el personal sociosanitario con demoras en el aislamiento que pudieron condicionar la dinámica de transmisión en los brotes. Es necesario revisar las prácticas de identificación de la enfermedad y el aislamiento entre el personal, énfasis en la implementación rápida de medidas de prevención.

COVID-19 versus SARS: A comparative review

The two genetically similar severe acute respiratory syndrome coronaviruses, SARS-CoV-1 and SARS-CoV-2, have each been responsible for global epidemics of vastly different scales. Although both viruses arose from similar origins, they quickly diverged due to differences in their transmission dynamics and spectrum of clinical presentations. The potential involvement of multiple organs systems, including the respiratory, cardiac, gastrointestinal and neurological, during infection necessitates a comprehensive understanding of the clinical pathogenesis of each virus. The management of COVID-19, initially modelled after SARS and other respiratory illnesses, has continued to evolve as we accumulate more knowledge and experience during the pandemic, as well as develop new therapeutics and vaccines. The impact of these two coronaviruses has been profound for our health care and public health systems, and we hope that the lessons learned will not only bring the current pandemic under control, but also prevent and reduce the impact of future pandemics.

Mass testing after a single suspected or confirmed case of COVID-19 in London care homes, April-May 2020: implications for policy and practice

Introduction: Previous investigations have identified high rates of SARS-CoV-2 infection among residents and staff in care homes reporting an outbreak of COVID-19. We investigated care homes reporting a single suspected or confirmed case to assess whether early mass testing might reduce risk of transmission during the peak of the pandemic in London.

Methods: Between 18–27 April 2020, residents and staff in care homes reporting a single case of COVID-19 to Public Health England had a nasal swab to test for SARS-CoV-2 infection by RT-PCR and subsequent whole genome sequencing. Residents and staff in two care homes were re-tested eight days later.

Results: Four care homes were investigated. SARS-CoV-2 positivity was 20% (65/333) overall, ranging between 3–59%. Among residents, positivity ranged between 3–76% compared to 3–40% in staff. Half of the SARS-CoV-2 positive residents (23/46, 50%) and 63% of staff (12/19) reported symptoms within 14 days before or after testing. Repeat testing 8 days later in two care homes with the highest infection rates identified only two new cases. Genomic analysis demonstrated a small number of introductions of the virus into care homes, and distinct clusters within three of the care homes.

Conclusions: We found extensive but variable rates of SARS-CoV-2 infection among residents and staff in care homes reporting a single case of COVID-19. While routine whole home testing has now been adopted into practice, care homes must remain vigilant and should be encouraged to report a single suspected case, which should trigger appropriate outbreak control measures.

SARS-CoV-2 in Nursing Homes after 3 Months of Serial, Facilitywide Point Prevalence Testing, Connecticut, USA

Nursing homes house populations that are highly vulnerable to coronavirus disease. Point prevalence surveys (PPSs) provide information on the severe acute respiratory syndrome coronavirus 2 infection status of staff and residents in nursing homes and enable isolation of infectious persons to halt disease spread. We collected 16 weeks of public health surveillance data on a subset of nursing homes (34/212) in Connecticut, USA. We fit a Poisson regression model to evaluate the association between incidence and time since serial PPS onset, adjusting for decreasing community incidence and other factors. Nursing homes conducted a combined total of 205 PPSs in staff and 232 PPSs in residents. PPS was associated with 41%-80% reduction in incidence rate in nursing homes. Our findings provide support for the use of repeated PPSs in nursing home staff and residents, combined with strong infection prevention measures such as cohorting, in contributing to outbreak control.

Demand for longer quarantine period among common and uncommon COVID-19 infections: a scoping review

BACKGROUND

As one of the non-pharmacological interventions to control the transmission of COVID-19, determining the quarantine duration is mainly based on the accurate estimates of the incubation period. However, patients with coarse information of the exposure date, as well as infections other than the symptomatic, were not taken into account in previously published studies. Thus, by using the statistical method dealing with the interval-censored data, we assessed the quarantine duration for both common and uncommon infections. The latter type includes the presymptomatic, the asymptomatic and the recurrent test positive patients.

METHODS

As of 10 December 2020, information on cases have been collected from the English and Chinese databases, including Pubmed, Google scholar, CNKI (China National Knowledge Infrastructure) and Wanfang. Official websites and medias were also searched as data sources. All data were transformed into doubly interval-censored and the accelerated failure time model was applied. By estimating the incubation period and the time-to-event distribution of worldwide COVID-19 patients, we obtain the large percentiles for determining and suggesting the quarantine policies. For symptomatic and presymptomatic COVID-19 patients, the incubation time is the duration from exposure to symptom onset. For the asymptomatic, we substitute the date of first positive result of nucleic acid testing for that of symptom onset. Furthermore, the time from hospital discharge or getting negative test result to the positive recurrence has been calculated for recurrent positive patients.

RESULTS

A total of 1920 laboratory confirmed COVID-19 cases were included. Among all uncommon infections, 34.1% (n = 55) of them developed symptoms or were identified beyond fourteen days. Based on all collected cases, the 95th and 99th percentiles were estimated to be 16.2 days (95% CI 15.5-17.0) and 22.9 days (21.7‒24.3) respectively. Besides, we got similar estimates based on merely symptomatic and presymptomatic infections as 15.1 days (14.4‒15.7) and 21.1 days (20.0‒22.2).

CONCLUSIONS

There are a certain number of infected people who require longer quarantine duration. Our findings well support the current practice of the extended active monitoring. To further prevent possible transmissions induced and facilitated by such infectious outliers after the 14-days quarantine, properly prolonging the quarantine duration could be prudent for high-risk scenarios and in regions with insufficient test resources.

Magnitude of asymptomatic COVID-19 cases throughout the course of infection: A systematic review and meta-analysis

BACKGROUND

Asymptomatic SARS-CoV-2 infections are responsible for potentially significant transmission of COVID-19. Worldwide, a number of studies were conducted to estimate the magnitude of asymptomatic COVID-19 cases. However, there is a need for more robust and well-designed studies to have a relevant public health intervention. Synthesis of the available studies significantly strengthens the quality of evidences for public health practice. Thus, this systematic review and meta-analysis aimed to determine the overall magnitude of asymptomatic COVID-19 cases throughout the course of infection using available evidences.

METHODS

We followed the PRISMA checklist to present this study. Two experienced review authors (MA and DBK) were systematically searched international electronic databases for studies. We performed meta-analysis using R statistical software. The overall weighted proportion of asymptomatic COVID-19 cases throughout the course infection was computed. The pooled estimates with 95% confidence intervals were presented using forest plot. Egger's tests were used to assess publication bias, and primary estimates were pooled using a random effects model. Furthermore, a sensitivity analysis was conducted to assure the robustness of the result.

RESULTS

A total of 28 studies that satisfied the eligibility criteria were included in this systematic review and meta-analysis. Consequently, in the meta-analysis, a total of 6,071 COVID-19 cases were included. The proportion of asymptomatic infections among the included studies ranged from 1.4% to 78.3%. The findings of this meta-analysis showed that the weighted pooled proportion of asymptomatic COVID-19 cases throughout the course of infection was 25% (95%CI: 16-38). The leave-one out result also revealed that the weighted pooled average of asymptomatic SARS-CoV-2 infection was between 28% and 31.4%.

CONCLUSIONS

In conclusion, one-fourth of SARS-CoV-2 infections are remained asymptomatic throughout the course infection. Scale-up of testing, which targeting high risk populations is recommended to tackle the pandemic.

IL-6-based mortality prediction model for COVID-19: Validation and update in multicenter and second wave cohorts

Background

Coronavirus disease 2019 (COVID-19) is a highly variable condition. Validated tools to assist in the early detection of patients at high risk of mortality can help guide medical decisions.

Objective

We sought to validate externally, as well as in patients from the second pandemic wave in Europe, our previously developed mortality prediction model for hospitalized COVID-19 patients.

Methods

Three validation cohorts were generated: 2 external with 185 and 730 patients from the first wave and 1 internal with 119 patients from the second wave. The probability of death was calculated for all subjects using our prediction model, which includes peripheral blood oxygen saturation/fraction of inspired oxygen ratio, neutrophil-to-lymphocyte ratio, lactate dehydrogenase, IL-6, and age. Discrimination and calibration were evaluated in the validation cohorts. The prediction model was updated by reestimating individual risk factor effects in the overall cohort (N = 1477).

Results

The mortality prediction model showed good performance in the external validation cohorts 1 and 2, and in the second wave validation cohort 3 (area under the receiver-operating characteristic curve, 0.94, 0.86, and 0.86, respectively), with excellent calibration (calibration slope, 0.86, 0.94, and 0.79; intercept, 0.05, 0.03, and 0.10, respectively). The updated model accurately predicted mortality in the overall cohort (area under the receiver-operating characteristic curve, 0.91), which included patients from both the first and second COVID-19 waves. The updated model was also useful to predict fatal outcome in patients without respiratory distress at the time of evaluation.

Conclusions

This is the first COVID-19 mortality prediction model validated in patients from the first and second pandemic waves. The COR+12 online calculator is freely available to facilitate its implementation (https://utrero-rico.shinyapps.io/COR12_Score/).

Epidemiology and clinical features of COVID-19 outbreaks in aged care facilities: A systematic review and meta-analysis

BACKGROUND

COVID-19 outbreaks in aged care facilities (ACFs) often have devastating consequences. However, epidemiologically these outbreaks are not well defined. We aimed to define such outbreaks in ACFs by systematically reviewing literature published during the current COVID-19 pandemic.

METHODS

We searched 11 bibliographic databases for literature published on COVID-19 in ACFs between December 2019 and September 2020. Original studies reporting extractable epidemiological data as part of outbreak investigations or non-outbreak surveillance of ACFs were included in this systematic review and meta-analysis. PROSPERO registration: CRD42020211424.

FINDINGS

We identified 5,148 publications and selected 49 studies from four continents reporting data on 214,380 residents in 8,502 ACFs with 25,567 confirmed cases of COVID-19. Aged care residents form a distinct vulnerable population with single-facility attack rates of 45% [95% CI 32-58%] and case fatality rates of 23% [95% CI 18-28%]. Of the cases, 31% [95% CI 28-34%] were asymptomatic. The rate of hospitalization amongst residents was 37% [95% CI 35-39%]. Data from 21 outbreaks identified a resident as the index case in 58% of outbreaks and a staff member in 42%. Findings from the included studies were heterogeneous and of low to moderate quality in risk of bias assessment.

INTERPRETATION

The clinical presentation of COVID-19 varies widely in ACFs residents, from asymptomatic to highly serious cases. Preventing the introduction of COVID-19 into ACFs is key, and both residents and staff are a priority group for COVID-19 vaccination. Rapid diagnosis, identification of primary and secondary cases and close contacts plus their isolation and quarantine are of paramount importance.

FUNDING

Queensland Advancing Clinical Research Fellowship awarded to Prof. Gulam Khandaker by Queensland Health's Health Innovation, Investment and Research Office (HIRO), Office of the Director-General.

Asymptomatic carriers of coronavirus disease 2019 among healthcare workers in Isfahan, Iran

Aim: This study aimed to investigate the prevalence of coronavirus disease 2019 (COVID-19) among healthcare workers (HCWs) in Isfahan, Iran. Materials & methods: HCWs in COVID-19 wards of three referral COVID-19 hospitals in Isfahan were screened and tested for COVID-19 infection. Results: In total, 102 HCWs were screened whose median age was 43 years old. Moreover, 21 (20.5%) of them had a history of suspected infection with SARS-CoV2, mostly (66.6%) without any symptoms while six (28.5%) of them suffered from relatively mild diseases and one (4.7%) was diagnosed with pulmonary embolism. Conclusion: It was found that HCWs were prone to be asymptomatic carriers while their computed tomography images were normal. Therefore, it is recommended that reverse-transcriptase real-time-PCR be essential for the diagnosis of infections.

Pre-operative prevalence of asymptomatic carriers of COVID-19 in hospitals in Catalonia during the first wave after the resumption of surgical activity

INTRODUCTION

The COVID-19 pandemic led to the cancellation of non-essential surgical procedures in March 2020. With the resumption of surgical activity, patients undergoing surgery were one of the first population groups to be systematically tested for PCR. The aim of this study was to determine the prevalence of asymptomatic SARS-CoV-2 carriers after the resumption of non-essential surgical activity.

METHODS

Retrospective multicenter observational study of patients scheduled for surgery or undergoing emergency surgery in Catalonia between 20 April and 31 May 2020. The microbiological results of preoperative PCR tests and clinical records were reviewed, and an epidemiological survey was conducted on patients with positive PCR for SARS-CoV-2.

RESULTS

A total of 10,838 patients scheduled for surgery or who underwent emergency surgery were screened for COVID-19. One hundred and eighteen patients (1.09%) were positive for SARS-CoV-2 in the 72hours prior to surgery. The prevalence of asymptomatic carriers was 0.7% (95%CI: 0.6% - 0.9%). The first week of the study presented the highest prevalence of asymptomatic carriers [1.9% (95%CI: 1.1%-3.2%)].

CONCLUSIONS

The low levels of asymptomatic carriers of COVID-19 infection obtained in the surgical population of hospitals in Catalonia after the resumption of surgical activity, shows that most patients were able to undergo surgical procedures without the risks of COVID-19 associated complications in the perioperative period.

COVID-19 in Health-Care Workers: A Living Systematic Review and Meta-Analysis of Prevalence, Risk Factors, Clinical Characteristics, and Outcomes

Health care workers (HCW) are at the frontline response to the new coronavirus disease 2019 (COVID-19), being at a higher risk of acquiring the disease, and subsequently, exposing patients and colleagues. Searches in eight bibliographic databases were performed to systematically review the evidence on the prevalence, risk factors, clinical characteristics, and prognosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among HCW. Ninety-seven studies (All published in 2020), including 230,398 HCW, met the inclusion criteria. From the screened HCW using RT-PCR and the presence of antibodies, the estimated prevalence of SARS-CoV-2 infection was 11% (95%CI; 7%-15%) and 7% (95% CI; 4%-11%), respectively. The most frequently affected personnel were the nurses (48%. 95%CI; 41%-56%), while most of the COVID-19 positive medical personnel were working in hospitalization/non-emergency wards during the screening (43%, 95%CI;28%-59%). Anosmia, fever and myalgia were identified as the only symptoms associated with HCW SARS-CoV-2 positivity. Among RT-PCR positive HCW, 40% (95%CI;17%-65%) did not show symptoms at the time of diagnosis. Finally, 5% (95%CI;3%-8%) of the COVID-19 positive HCW developed severe clinical complications, and 0.5% (95% CI; 0.02%-1.3%) died. HCW suffer a significant burden from COVID-19, with HCW working in hospitalization/non-emergency wards and nurses being the most infected personnel.

Coronavirus disease 2019 (COVID-19) in long-term care facilities: A review of epidemiology, clinical presentations, and containment interventions

Long-term care facilities (LTCFs) and their populations have been greatly affected by the coronavirus disease 2019 (COVID-19) pandemic. In this review, we summarize the literature to describe the current epidemiology of COVID-19 in LTCFs, clinical presentations and outcomes in the LTCF population with COVID-19, containment interventions, and the role of healthcare workers in SARS-CoV-2 transmission in these facilities.