In late December 2019 a novel coronavirus infection (COVID-19, SARS-CoV2) emerged from Wuhan, China and quickly became a pandemic with unprecedented impact on worldwide health care systems, social practices, and economies. 1 By September 2020, COVID-19 infected over 28 million people and resulted in nearly 900,000 deaths across 188 countries. The first known case in the United States (US) occurred in January 2020 and there are now more than 6.4 million cases and over 191,000 deaths nationally. [1] [2] [3] Early data from China and Europe suggest people with older age, hypertension, diabetes, and obesity are at increased risk of having a more serious illness course and death. 4, 5 While US data reflects a similar pattern of disease severity and mortality among older patients with pre-existing medical conditions, several reports also highlight a disproportionate burden of COVID-19 infection and related morbidity and mortality among racial and ethnic minorities. 6 As of June 2020, Black and Latinx people accounted for 22% and 33% of total COVID-19 cases in the US but make up only 13% and 16% of the total US population, respectively. 7 In addition limited preliminary data shows Latinx communities have a higher daily positivity rate in certain parts of Northeastern US including Baltimore, Maryland. 8 In New York City, the initial US epicenter of the pandemic, Latinx patients constituted 29% of the population but mortality was 34% with similar disparities amongst Blacks who made up 24% of the population but 28% of the mortality. 9 Blacks have also been shown to have higher rates of hospitalization for COVID-19 than all other groups, and have higher mortality rates than whites. 10 These statistics from national data are reflected in local communities within California. At the end of April 2020, the University of California, San Francisco performed COVID-19 tests on nearly 3,000 residents and workers in the highly diverse Mission District of San Francisco and reported a 2.1% test positivity rate. Despite making up only 44% of those tested, Latinx patients accounted for 95% of those testing positive. This report also suggests that people who had lower annual income levels, greater household sizes and were unable to work from home, were more likely to test positive for COVID-19. 11, 12 Nonetheless overall disease prevalence is still likely underestimated in Black and Latinx communities due to notably poor access to testing for these populations. 6 Differences in COVID-19 health outcomes have been attributable to underlying racial and ethnic health disparities rooted in systemic racism and marginalization. These disparities have resulted in social and economic inequality including limited access to housing, healthy food options, healthcare facilities and health insurance. Language barriers and epigenetic health effects of racial bias have also been cited as major contributors. [13] [14] [15] [16] [17] [18] [19] Blacks have a higher rate of chronic health conditions at a younger age compared to the general population and have the highest rates of death from heart disease, cerebrovascular disease, cancer and HIV/AIDS compared to all other racial and ethnic groups in the US. Latinx Americans are almost twice as likely as their non-Latinx counterparts to die from diabetes. 19, 20 These health disparities have been associated with increased risk of severe illness from COVID-19 infection. 21 J o u r n a l P r e -p r o o f Journal Pre-proof Importance As a safety net provider, EDs provide care to medically and socially vulnerable populations. Data has shown that significant number of symptomatic patients present to EDs for influenza-like illness (ILI) and testing for COVID-19. 22 Safety net EDs have an important role in evaluating racial and ethnic minorities with ILI who have inequitable access to COVID-19 testing. 23 To our knowledge there is no existing literature on the racial and ethnic disparities in COVID-19 positivity among symptomatic patients tested for COVID-19 in the ED setting. Results from ED-based testing can identify racial and ethnic disparities in COVID-19 testing, test positivity rates, and morbidity and mortality that can be used by public health departments to inform policy and distribution of resources.
We aim to examine racial and ethnic disparities in COVID-19 disease burden among patients tested in three EDs that are part of an integrated public healthcare system. We use multivariable logistic regression analysis to assess for demographic and clinical factors associated with COVID-19 test positivity, and we examine the 30-day in hospital mortality among patients admitted with COVID-19.
This is a retrospective cohort study of patients tested for COVID-19 at three EDs within the Alameda Health System (AHS) between April 6 to May 4, 2020. April 6 was chosen as the study start date because this is the date when COVID-19 testing first became available for ED patients at AHS. Prior to this time, only patients admitted to the hospital were eligible for COVID-19 testing. This study was approved by the AHS Institutional Review Board with a waiver of written informed consent as the study posed no more than minimal risk to patients. We adhered to STROBE guidelines for conducting observational studies in epidemiology.
The primary outcome was COVID-19 test positivity rate stratified by race and ethnicity, and the secondary outcome was 30-day in hospital mortality. We also report descriptive data on the epidemiology of COVID-19 among patients presenting to AHS EDs.
Alameda Health System is an integrated public health system with three medical EDs that geographically span Alameda County, California: 1) Highland Hospital is an urban teaching hospital in Oakland, with an accredited 4-
year Emergency Medicine residency program, and an annual volume of 65,000 patients per year; 2) San Leandro During the study period, guidelines for testing were issued by the AHS COVID-19 Testing Committee, a multidisciplinary working group of physicians from infectious disease, laboratory, emergency and internal medicine.
Due to a limited supply of COVID-19 tests, testing was restricted to the ED, the Highland urgent care clinic, and the inpatient medicine service. Test eligibility criteria were agreed upon and distributed across the medical system. Eligible patients included: 1) those admitted to the medicine service for presumed COVID-19 infection; 2) ED patients with a clinical syndrome consistent with COVID-19 infection, who did not require hospitalization, but determined by the treating physician to be of moderate to high risk for a severe illness course due to medical comorbidities such as diabetes, heart disease, pulmonary disease, or kidney disease; or any patient felt to be infected with COVID-19 with who had social factors impacting disease transmission and community spread, such as being homeless or congregate living. AHS is unable to accommodate direct inpatient admissions from the community or from other facilities; therefore, all patients admitted for COVID-19 were admitted through the ED. COVID-19
testing was performed using PCR assays and conducted at either the Alameda County Department of Public Health Laboratory or the University of California San Francisco Laboratory.
All unique ED patients tested for COVID-19 were eligible for inclusion. We excluded tests performed during inpatient admission, as part of disease monitoring or assessment for viral clearance, and those performed in the urgent care. Only the index ED COVID-19 test was included in the analysis for patients who had multiple tests.
Race and ethnicity was self-identified by patients during ED registration from fixed categories.
We analyzed data from the electronic health record (EHR) and stored it in REDCap (a secure online data collection instrument). REDCap was used by the AHS ED COVID-19 public health team for follow-up and surveillance protocols. All patients who were tested for COVID-19 at an AHS ED were included in this dataset. Patients who tested positive for COVID-19 had past medical and social history documented in the dataset prospectively, and study investigators conducted a retrospective chart review for patients who tested negative for COVID-19. The past medical and social history in the REDCap data collection instrument included co-morbidities, social/epidemiological factors (homelessness, group living, behavioral health concerns), race, ethnicity, age, and primary care physicians (PCP) information. We conducted a final review of admitted patients on f 4, 2020 to assess for 30-day in hospital mortality.
Descriptive analyses were performed for all variables. Categorical data are reported as numbers and percentages and continuous data are reported as means with standard deviation (SD). Bivariate statistical tests, including the Wilcoxon rank sum test, the chi-square tests, or Fisher's exact test, were used to compare variables. We conducted a power analysis for the regression model to ensure adequate power of 0.8 as convention to detect a 6% difference in test positivity between racial and ethnic groups. To adequately power the study, we found we needed 457 unique J o u r n a l P r e -p r o o f Journal Pre-proof patient encounters. We pre-specified the regression model to contain COVID-19 positivity as the dependent variable, with the following predictor variables: race and ethnicity; age; medical co-morbidities (that may influence disease severity); documented epidemiologic concern (defined as healthcare worker or living with elderly family members); skilled nursing facility residence; whether or not a patient had a PCP (to control for access to medical care); and which AHS ED conducted the test to control for geographic and hospital site clustering. All analysis was performed in Stata version 13.1 (Statacorp, College Station, TX).
There were 526 patients tested for COVID-19 in the AHS EDs from April 6 through May 4, 2020, of whom 95 (18.1%) tested positive. Demographics of patients tested for COVID-19 from the overall cohort, as well as from each ED, can be found in Table 1 Table 3 shows the rates of hospital admission and in-hospital mortality for patients who tested positive for COVID- 19 . Of the 95 patients with COVID-19, 52 (54.7%) were admitted (17 required ICU care), 4 (4.2%) died, and 2 (2.1%) were still in the hospital as of June 4 th 2020. Of the two patients remaining in the hospital, 1 was white and 1 was Latinx. The mean age of patients admitted to the ICU was 63.7 (SD 14.6) and the mean age of the patients who died was 82.5 (SD 8.4); all 4 patients who died lived in a skilled nursing facility and had >3 chronic medical conditions. Crude mortality among Black patients was significantly higher than non-Black patients (18.7% vs 1.3%, p<0.01)
Our study reports the outcomes of ED-based COVID-19 testing within a single health care system in Northern California and may not be generalizable to other care settings. Importantly, COVID-19 testing was driven by an institutionally defined policy, determined by local expert consensus to test vulnerable populations with severe symptoms, and influenced, in part, by test availability. Our data does not report the prevalence of COVID-19 within our ED population, but rather the positivity rate among a selected group of symptomatic and vulnerable patients.
Our data does not allow for the comparison of patients with cough, fever, or ILI who may have met our eligibility criteria for COVID-19 testing, but who were not tested. During the time-period of this study we did not have a diagnosis code for suspected COVID-19 and our EHR screening tool was based on travel history and not symptoms.
How the role of race, ethnicity, and other factors, such as language barriers, bias COVID-19 testing requires further study.
Lastly, given the small numbers of deaths in our study population using a 30-day inpatient mortality outcome, we were unable to control for factors associated with mortality, such as medical comorbidities, race/ethnicity, or socioeconomic variables.
Among patients tested across three urban EDs in an integrated public health system in Northern California, we found significantly higher COVID-19 positivity in the Latinx community. While ED testing within an integrated Area and California. 10 One definition of a healthcare disparity is defined as a difference in outcome by race or ethnicity not attributable to access to care. 23 A strength of our study is that we demonstrate the disparity in COVID-19 test positivity rate to be significant even after controlling for access to care, age, medical co-morbidities, social factors and site of testing. This analysis helps frame the discussion around healthcare disparities and can focus responses tailored to specific communities.
The higher rate of positivity in Latinx patients may be explained by socioeconomic factors that put these communities at greater risk for exposure to infection. Of the nearly 3,000 people tested for COVID-19 in the San Francisco Mission study, 62 were positive, 95% of whom were Latinx. Of the 62 patients who tested positive for COVID-19 in this study, 90% stated they were unable to work from home, 89.9% reported a household income of <$50,000 per year, 59.6% report a total household size of 3-5 people and 28.8% of >5 people. [11] [12] These factors may hold true in our population as well, although we did not examine the contribution of socioeconomic status and COVID-19 test positivity in our study. Racial and ethnic minorities are more likely to live in densely populated areas, in multi-generational group homes, and have a higher representation in jails, prisons and detention centers. 25 In addition, many racial and ethnic minorities are more likely to work as essential workers in the service industry.
These include positions in agriculture, in meat packing plants, as day laborers, and as caretakers where maintaining social distancing is difficult. One such example is the recent outbreak of COVID-19 in workers in the meat-packing industry, most of whom are Latinx, that was significant enough to cause a national decrease in the US meat supply. 26, 27 Moreover, Latinx have the lowest rates of paid sick leave and may not be financially able to take time off work when they or a family member gets sick with COVID-19. 28 In our study, we found that the median age of Latinx patients who tested positive for COVID-19 to be nearly 20 years younger than non-Latinx patients, suggesting that this community may be more likely to be working and unable to shelter in place at home due to financial obligations.
Within AHS, Highland and San Leandro Hospitals had higher test positivity rates of COVID-19 (19.8% and 24.4% respectively) compared to Alameda Hospital (2.6%), which cares for a slightly less diverse patient population with a higher proportion of patients that have private insurance. These findings highlight the unequal impact on hospitals caring for vulnerable populations and the disparate impact of COVID-19 geographically, even within integrated health systems.
While our sample size is relatively small, we did find a higher unadjusted mortality rate among Black patients. This disparity is consistent with other published data from the COVID-19 pandemic [6] [7] [8] [9] . However, it is difficult to interpret due to the small overall number of deaths at AHS during this time period. A recent study of 3,626 patients in a large cohort in Louisiana revealed that 70.6% of patients hospitalized for COVID-19 who died were Black even though they comprised only 31% of the population. 29 Our findings suggest that future work should not only take into account disparities in disease burden within a health system, but also disparities in mortality within each community.
Despite the higher test positivity rate among Latinx patients, the relatively lower mortality and ICU admission rates J o u r n a l P r e -p r o o f Journal Pre-proof may be age related. Among our cohort, Latinx patients diagnosed with COVID-19 were significantly younger than non-Latinx patients. These findings highlight the need for focused interventions that target both the Black and Latinx communities.
Emergency departments have a history of engaging in public health and epidemiology, shaping screening recommendations and detecting outbreaks for influenza, HIV, and hepatitis C virus infections. [31] [32] [33] A similar approach should be implemented among EDs during the COVID-19 pandemic. As part of the public health programs, EDs can monitor for outbreaks and disparities in disease burden as well as implement targeted and culturally appropriate contact tracing. The data collected as part of ED surveillance has helped to inform public health policies: including prioritizing stand-up testing sites in neighborhoods with high proportions of Latinx citizens and identifying the need for isolation housing for patients living in households with high numbers of people.
In the time since this study period ended, the ED public health team contributed data to the county identifying an emerging outbreak among Mexican and Guatemalan communities who primarily speak Mayan indigenous languages, and the AHS ED public health team became a part of the newly formed Alameda County COVID-19
Latinx Task Force.
While community testing sites have increased significantly since the onset of the pandemic, EDs will remain highvolume testing locations for COVID-19 for the most symptomatic patients, as well as patients coming from disadvantaged communities. Safety-net EDs may be more sensitive to the early detection of outbreaks in vulnerable populations, including immigrant communities, patients experiencing homelessness, as well as those with significant psychiatric and substance use disorders. Close attention to these communities is critical to COVID-19 public health responses, and EDs should leverage any existing public health infrastructure for these purposes. For example, staff from the AHS HIV and hepatitis C virus screening program were re-tailored to facilitate COVID-19 follow up, wellness checks, and care coordination with primary care and the public health department using pre-existing relationships and workflows. Additional AHS emergency medicine public health collaborations have included standup community testing sites under the direction of an EM physician working with the county public health department for neighborhoods disproportionately impacted by COVID-19, while another EM physician has spearheaded efforts to house patients experiencing homelessness affected by COVID-19. 34, 35 Lastly, as the COVID-19 pandemic ebbs and flows, there will be an increased role for ED testing of both symptomatic and asymptomatic patients. Close coordination with public health departments and contact tracing programs will be critical to sustaining low rates of transmission within communities.
Among three EDs in an integrated public health system, we report a significant disparity in COVID-19 disease burden in the Latinx community, and disproportionate mortality among Black patients. These findings are consistent with other regional and national data and suggest that where racial and ethnic minorities live and work contributes to a greater risk of infection with COVID-19. These communities are often less able to shelter in place, work from Ethnicity is non-Latinx unless specified. Epidemiologic concern (as documented in the medical record) defined by: living with family member over 60 years old, lives with family members with chronic diseases (diabetes, lung disease, heart disease), healthcare workers, other essential service worker. Medical co-morbidity (as documented in the medical record) defined by: diabetes, hypertension, chronic or end stage kidney disease, human immunodeficiency virus, chronic obstructive pulmonary disease or asthma, active cancer, history of stroke, or current smoker. 