Workplace interventions to reduce the risk of SARS-CoV-2 infection outside of healthcare settings.

BACKGROUND: Although many people infected with SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) experience no or mild symptoms, some individuals can develop severe illness and may die, particularly older people and those with underlying medical problems. Providing evidence-based interventions to prevent SARS-CoV-2 infection has become more urgent with the potential psychological toll imposed by the coronavirus disease 2019 (COVID-19) pandemic. Controlling exposures to occupational hazards is the fundamental method of protecting workers. When it comes to the transmission of viruses, workplaces should first consider control measures that can potentially have the most significant impact. According to the hierarchy of controls, one should first consider elimination (and substitution), then engineering controls, administrative controls, and lastly, personal protective equipment. This is the first update of a Cochrane review published 6 May 2022, with one new study added. OBJECTIVES: To assess the benefits and harms of interventions in non-healthcare-related workplaces aimed at reducing the risk of SARS-CoV-2 infection compared to other interventions or no intervention. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, Web of Science Core Collections, Cochrane COVID-19 Study Register, World Health Organization (WHO) COVID-19 Global literature on coronavirus disease, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform, and medRxiv to 13 April 2023. SELECTION CRITERIA: We included randomised controlled trials (RCTs) and non-randomised studies of interventions. We included adult workers, both those who come into close contact with clients or customers (e.g. public-facing employees, such as cashiers or taxi drivers), and those who do not, but who could be infected by coworkers. We excluded studies involving healthcare workers. We included any intervention to prevent or reduce workers' exposure to SARS-CoV-2 in the workplace, defining categories of intervention according to the hierarchy of hazard controls (i.e. elimination; engineering controls; administrative controls; personal protective equipment). DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were incidence rate of SARS-CoV-2 infection (or other respiratory viruses), SARS-CoV-2-related mortality, adverse events, and absenteeism from work. Our secondary outcomes were all-cause mortality, quality of life, hospitalisation, and uptake, acceptability, or adherence to strategies. We used the Cochrane RoB 2 tool to assess risk of bias, and GRADE methods to evaluate the certainty of evidence for each outcome. MAIN RESULTS: We identified 2 studies including a total of 16,014 participants. Elimination-of-exposure interventions We included one study examining an intervention that focused on elimination of hazards, which was an open-label, cluster-randomised, non-inferiority trial, conducted in England in 2021. The study compared standard 10-day self-isolation after contact with an infected person to a new strategy of daily rapid antigen testing and staying at work if the test is negative (test-based attendance). The trialists hypothesised that this would lead to a similar rate of infections, but lower COVID-related absence. Staff (N = 11,798) working at 76 schools were assigned to standard isolation, and staff (N = 12,229) working at 86 schools were assigned to the test-based attendance strategy. The results between test-based attendance and standard 10-day self-isolation were inconclusive for the rate of symptomatic polymerase chain reaction (PCR)-positive SARS-CoV-2 infection (rate ratio (RR) 1.28, 95% confidence interval (CI) 0.74 to 2.21; 1 study; very low-certainty evidence). The results between test-based attendance and standard 10-day self-isolation were inconclusive for the rate of any PCR-positive SARS-CoV-2 infection (RR 1.35, 95% CI 0.82 to 2.21; 1 study; very low-certainty evidence). COVID-related absenteeism rates were 3704 absence days in 566,502 days-at-risk (6.5 per 1000 working days) in the control group and 2932 per 539,805 days-at-risk (5.4 per 1000 working days) in the intervention group (RR 0.83, 95% CI 0.55 to 1.25). We downgraded the certainty of the evidence to low due to imprecision. Uptake of the intervention was 71% in the intervention group, but not reported for the control intervention. The trial did not measure our other outcomes of SARS-CoV-2-related mortality, adverse events, all-cause mortality, quality of life, or hospitalisation. We found seven ongoing studies using elimination-of-hazard strategies, six RCTs and one non-randomised trial. Administrative control interventions We found one ongoing RCT that aims to evaluate the efficacy of the Bacillus Calmette-Guérin (BCG) vaccine in preventing COVID-19 infection and reducing disease severity. Combinations of eligible interventions We included one non-randomised study examining a combination of elimination of hazards, administrative controls, and personal protective equipment. The study was conducted in two large retail companies in Italy in 2020. The study compared a safety operating protocol, measurement of body temperature and oxygen saturation upon entry, and a SARS-CoV-2 test strategy with a minimum activity protocol. Both groups received protective equipment. All employees working at the companies during the study period were included: 1987 in the intervention company and 1798 in the control company. The study did not report an outcome of interest for this systematic review. Other intervention categories We did not find any studies in this category. AUTHORS' CONCLUSIONS: We are uncertain whether a test-based attendance policy affects rates of PCR-positive SARS-CoV-2 infection (any infection; symptomatic infection) compared to standard 10-day self-isolation amongst school and college staff. A test-based attendance policy may result in little to no difference in absenteeism rates compared to standard 10-day self-isolation. The non-randomised study included in our updated search did not report any outcome of interest for this Cochrane review. As a large part of the population is exposed in the case of a pandemic, an apparently small relative effect that would not be worthwhile from the individual perspective may still affect many people, and thus become an important absolute effect from the enterprise or societal perspective. The included RCT did not report on any of our other primary outcomes (i.e. SARS-CoV-2-related mortality and adverse events). We identified no completed studies on any other interventions specified in this review; however, eight eligible studies are ongoing. More controlled studies are needed on testing and isolation strategies, and working from home, as these have important implications for work organisations.

Workplace interventions to reduce the risk of SARS-CoV-2 infection outside of healthcare settings.

BACKGROUND: Although many people infected with SARS-CoV-2 (severe acute respiratory syndrome coronavirus-2) experience no or mild symptoms, some individuals can develop severe illness and may die, particularly older people and those with underlying medical problems. Providing evidence-based interventions to prevent SARS-CoV-2 infection has become more urgent with the spread of more infectious SARS-CoV-2 variants of concern (VoC), and the potential psychological toll imposed by the coronavirus disease 2019 (COVID-19) pandemic.   Controlling exposures to occupational hazards is the fundamental method of protecting workers. When it comes to the transmission of viruses, such as SARS-CoV-2, workplaces should first consider control measures that can potentially have the most significant impact. According to the hierarchy of controls, one should first consider elimination (and substitution), then engineering controls, administrative controls, and lastly, personal protective equipment (PPE). OBJECTIVES: To assess the benefits and harms of interventions in non-healthcare-related workplaces to reduce the risk of SARS-CoV-2 infection relative to other interventions, or no intervention. SEARCH METHODS: We searched MEDLINE, Embase, Web of Science, Cochrane COVID-19 Study Register, the Canadian Centre for Occupational Health and Safety (CCOHS), Clinicaltrials.gov, and the International Clinical Trials Registry Platform to 14 September 2021. We will conduct an update of this review in six months. SELECTION CRITERIA: We included randomised control trials (RCT) and planned to include non-randomised studies of interventions. We included adult workers, both those who come into close contact with clients or customers (e.g. public-facing employees, such as cashiers or taxi drivers), and those who do not, but who could be infected by co-workers. We excluded studies involving healthcare workers. We included any intervention to prevent or reduce workers' exposure to SARS-CoV-2 in the workplace, defining categories of intervention according to the hierarchy of hazard controls, i.e. elimination; engineering controls; administrative controls; personal protective equipment. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were incidence rate of SARS-CoV-2 infection (or other respiratory viruses), SARS-CoV-2-related mortality, adverse events, and absenteeism from work. Our secondary outcomes were all-cause mortality, quality of life, hospitalisation, and uptake, acceptability, or adherence to strategies. We used the Cochrane RoB 2 tool to assess the risk of bias, and GRADE methods to assess the certainty of evidence for each outcome. MAIN RESULTS: Elimination of exposure interventions We included one study examining an intervention that focused on elimination of hazards. This study is an open-label, cluster-randomised, non-inferiority trial, conducted in England in 2021. The study compared standard 10-day self-isolation after contact with an infected person to a new strategy of daily rapid antigen testing and staying at work if the test is negative (test-based attendance). The trialists hypothesised that this would lead to a similar rate of infections, but lower COVID-related absence. Staff (N = 11,798) working at 76 schools were assigned to standard isolation, and staff (N = 12,229) at 86 schools to the test-based attendance strategy.  The results between test-based attendance and standard 10-day self-isolation were inconclusive for the rate of symptomatic PCR-positive SARS-COV-2 infection rate ratio ((RR) 1.28, 95% confidence interval (CI) 0.74 to 2.21; 1 study, very low-certainty evidence)). The results between test-based attendance and standard 10-day self-isolation were inconclusive for the rate of any PCR-positive SARS-COV-2 infection (RR 1.35, 95% CI 0.82 to 2.21; 1 study, very low-certainty evidence). COVID-related absenteeism rates were 3704 absence days in 566,502 days-at-risk (6.5 per 1000 days at risk) in the control group and 2932 per 539,805 days-at-risk (5.4 per 1000 days at risk) in the intervention group (RR 0.83; 95% CI 0.55 to 1.25). The certainty of the evidence was downgraded to low, due to imprecision. Uptake of the intervention was 71 % in the intervention group, but not reported for the control intervention.  The trial did not measure other outcomes, SARS-CoV-2-related mortality, adverse events, all-cause mortality, quality of life, and hospitalisation. We found one ongoing RCT about screening in schools, using elimination of hazard strategies. Personal protective equipment We found one ongoing non-randomised study on the effects of closed face shields to prevent COVID-19 transmission. Other intervention categories We did not find studies in the other intervention categories. AUTHORS' CONCLUSIONS: We are uncertain whether a test-based attendance policy affects rates of PCR-postive SARS-CoV-2 infection (any infection; symptomatic infection) compared to standard 10-day self-isolation amongst school and college staff. Test-based attendance policy may result in little to no difference in absence rates compared to standard 10-day self-isolation. As a large part of the population is exposed in the case of a pandemic, an apparently small relative effect that would not be worthwhile from the individual perspective may still affect many people, and thus, become an important absolute effect from the enterprise or societal perspective.  The included study did not report on any other primary outcomes of our review, i.e. SARS-CoV-2-related mortality and adverse events. No completed studies were identified on any other interventions specified in this review, but two eligible studies are ongoing. More controlled studies are needed on testing and isolation strategies, and working from home, as these have important implications for work organisations.

Awareness of eye diseases and risk factors: identifying needs for health education and promotion in Canada.

BACKGROUND: Little is known about the level of general public knowledge in Canada regarding the risk factors, prevention, and treatment of major blinding eye diseases. METHODS: The study was a cross-sectional survey using self-administered questionnaires of patients presenting to 33 family practitioners' offices in British Columbia. We asked patients' opinions on the "value" of preventing blindness; the possibility of preventing cataract, glaucoma, and macular degeneration; the possibility of treating these conditions; and their knowledge of risk factors. RESULTS: A total of 882 adults completed the questionnaires. Preventing vision loss was reported as one of 2 top health priorities in 28% of the questionnaires, more commonly by those with higher education and non-European ancestry. Overall, 69.2% reported familiarity with cataract as a cause of vision loss, 41.2% with glaucoma, and 20.2% with macular degeneration. Of these, 97.5% recognized the possibility of treatment for cataract, 91.5% for glaucoma, and 77.0% for macular degeneration, yet few respondents knew risk factors (amenable to intervention) for specific eye diseases. Men and younger respondents were more likely to report not knowing risk factors. Chinese-Canadians were least familiar with the association between smoking and cataract. Family history, probably the most important factor to help diagnose glaucoma, was recognized by only 23% of respondents. INTERPRETATION: Although loss of vision was reported as a major medical concern, there is little understanding of the risk factors for different eye diseases. The association of non-European ancestry and low educational attainment with poor knowledge of eye diseases suggests that innovative education programmes in primary and secondary schools and in non-English languages are needed to improve knowledge, attitudes, and practices.

RESIO revisited: visual function assessment and cataract surgery in British Columbia.

BACKGROUND: Cataract surgery in a population with mild levels of functional impairment was studied in the Regional Evaluation of Surgical Indications and Outcomes (RESIO) project. The RESIO investigators assessed the overall visual function assessment (VFA) score before and after surgery. In this study we reanalysed available RESIO data to better understand the findings for individual VFA items in this patient population. METHODS: We calculated effect sizes for longitudinal changes in each VFA item and for changes in overall VFA scores using the Mann-Whitney statistic. We considered effect sizes less than 0.3 as small, between 0.3 and 0.8 as moderate, and more than 0.8 as large. We compared differences in the individual VFA item scores before and after cataract surgery using a paired t test and Wilcoxon's signed-rank test. RESULTS: Of the 32 surgeons originally involved in the RESIO project, 18 (60%) agreed to have the data for their patients reanalysed. We found pre- and postoperative VFA data for 709 cataract operations (mean age of patients 73.4 years [standard deviation 9.4 years]; 60.7% women). Of the 47 people with a perfect preoperative VFA score, 28 (59.6%) had a perfect score postoperatively, 13 (27.6%) had a score of 90 or better, 5 (10.6%) had a score of 87 to 90, and 1 (2.1%) had a score of 67. Among the 200 people with a preoperative VFA score of 90 to 99, postoperatively the VFA score improved for 146 (73.0%), remained the same for 43 (21.5%) and worsened for 11 (5.5%). The mean scores for all individual VFA items improved postoperatively. The largest improvements were noted for "driving during the day" (effect size 1.1), "self-care activities" (0.8), "driving during the night" (0.5), "doing fine handiwork" (0.5), "reading newspaper or book" (0.4) and "participating in religious activities" (0.4). INTERPRETATION: The original conclusion from the RESIO project seems correct: based on VFA, the current threshold for cataract surgery in British Columbia is very low. Individual VFA items, particularly reading and night driving, are most strongly and consistently influenced by cataract surgery, regardless of overall VFA score. In the absence of visual acuity data, it is not possible to relate VFA to cataract surgical decision-making in British Columbia.

Cataract surgical outcome at the Vancouver Eye Care Centre: can it be predicted using current data?

BACKGROUND: Patients selected for cataract surgery have an increasingly wider range of coexisting ocular and systemic diseases. The aim of this study was to determine whether preoperative patient characteristics can assist surgeons in identifying patients who are at increased risk of having little or no improvement in visual outcome after cataract surgery. METHODS: We prospectively studied a randomly selected subset (20%) of patients with cataract undergoing cataract extraction at a tertiary centre in Vancouver. There were no patient exclusion criteria. Pre-, intra- and postoperative clinical data were collected from medical records. RESULTS: We studied 1329 cataract surgical procedures from March 1999 to December 2000. Of the 1329, 851 had complete pre- and postoperative visual acuity data. The mean age of the 851 patients was 73.2 (standard deviation 10.6) years, 575 (67.6%) were women, and 472 procedures (55.5%) were first-eye procedures. Preoperatively, the best-corrected visual acuity was 20/40 or better in 146 eyes (17.2%), 20/50 in 173 (20.3%), 20/60 to 20/70 in 248 (29.1%), and 20/80 or worse in 284 (33.4%). Almost half of the patients (419 [49.2%]) had at least one coexisting eye disease in the operated eye. At about 3 months postoperatively, the best-corrected visual acuity had improved in 786 eyes (92.4%), remained the same in 42 (4.9%) and had worsened in 23 (2.7%). Of the 23 eyes with worse visual acuity, half had preoperative visual acuity of 20/40 or better; most of the remaining eyes had preoperative vision of 20/50 to 20/70. Of the 42 eyes with unchanged vision, 22 (52%) had preoperative visual acuity worse than 20/100; the remaining eyes were distributed across the visual acuity range. An increase of 1 year of age increased the odds of having a poor visual acuity outcome by 2% to 4%. Worse preoperative visual acuity predicted an increased likelihood of a poor outcome; this effect increased sharply for eyes with preoperative visual acuity of 20/80 or worse. After adjustment for age and preoperative visual acuity, patients with three or more coexisting eye diseases in the operated eye were 10 to 24 times more likely to have the worst postoperative visual acuity. INTERPRETATION: The presence and number of coexisting ocular diseases, increased age and poor preoperative visual acuity predicted an unchanged or worse visual acuity after cataract surgery.

Cataract surgery at the Vancouver Eye Care Centre: do patient indications meet provincial clinical practice guidelines?

BACKGROUND: Cataract surgery, already the most common elective surgical procedure among patients over the age of 65 in North America, is rising in volume, because the population is aging while at the same time holding growing expectations of continued vitality. In meeting the need, there is a public interest in ensuring that cataract surgery is used appropriately. The purpose of this paper was to investigate the indication for cataract surgery performed in adults at a large tertiary care centre in Vancouver and to determine the extent to which patient criteria met the guidelines of the College of Physicians & Surgeons of British Columbia. METHODS: Patients attending the centre were enrolled in the cataract outcome assessment program through systematic sampling that included every patient with a personal health card number ending in 5 or 8 (20% of patients). There were no patient exclusion criteria. Pre-, intra- and postoperative clinical information was collected from patients' medical records. Patients were also sent a pre- and postoperative visual function and quality-of-life questionnaire. RESULTS: A total of 1098 cataract surgery procedures were performed in 896 patients from March 1999 to December 2000. The average age of the patients was 72.9 years; most (69.5%) were women. Just over half of the procedures (620 [56.6%]) were performed as first-eye surgery. In 191 cases (17.9%) the preoperative visual acuity was 20/40 or better in the affected eye. In most cases (82.1%) visual acuity of 20/50 or worse was the indication for surgery. In 89 cases (8.3%) there was not enough information in the chart to justify the surgery. INTERPRETATION: By examining standard information provided in patients' medical records, we were able to determine the indication for cataract surgery in 92% of cases. The most common indication was poor visual acuity.