COVID-19 cases reported in Colorado following screening at selected US airports, January - July 2020.

OBJECTIVE: We sought to estimate the proportion of air travelers who may have been infected with SARS-CoV-2 upon arrival to Colorado by comparing data on Colorado residents screened upon entering the US to COVID-19 cases reported in the state. Data on Colorado's screened passengers arriving into the US between January 17 and July 30, 2020 were compared to Colorado's Electronic Disease Reporting System. We conducted a descriptive analysis of true matches, including age, gender, case status, symptom status, time from arrival to symptom onset (days), and time from arrival to specimen collection date (days). RESULTS: Fourteen confirmed COVID-19 cases in travelers who were diagnosed within 14 days after arriving in Colorado were matched to the 8,272 travelers who underwent screening at 15 designated airports with a recorded destination of Colorado, or 0.2%. Most (N = 13/14 or 93%) of these infected travelers arrived in Colorado in March 2020; 12 (86%) of them were symptomatic. Entry screening for COVID-19 and the sharing of traveler information with the Colorado Department of Public Health and Environment appeared to identify few cases early in the pandemic. Symptom-based entry screening and sharing of traveler information was minimally effective at decreasing travel-associated COVID-19 transmission.

COVID-19 Mortality in the Colorado Center for Personalized Medicine Biobank.

Over 6.37 million people have died from COVID-19 worldwide, but factors influencing COVID-19-related mortality remain understudied. We aimed to describe and identify risk factors for COVID-19 mortality in the Colorado Center for Personalized Medicine (CCPM) Biobank using integrated data sources, including Electronic Health Records (EHRs). We calculated cause-specific mortality and case-fatality rates for COVID-19 and common pre-existing health conditions defined by diagnostic phecodes and encounters in EHRs. We performed multivariable logistic regression analyses of the association between each pre-existing condition and COVID-19 mortality. Of the 155,859 Biobank participants enrolled as of July 2022, 20,797 had been diagnosed with COVID-19. Of 5334 Biobank participants who had died, 190 were attributed to COVID-19. The case-fatality rate was 0.91% and the COVID-19 mortality rate was 122 per 100,000 persons. The odds of dying from COVID-19 were significantly increased among older men, and those with 14 of the 61 pre-existing conditions tested, including hypertensive chronic kidney disease (OR: 10.14, 95% CI: 5.48, 19.16) and type 2 diabetes with renal manifestations (OR: 5.59, 95% CI: 3.42, 8.97). Male patients who are older and have pre-existing kidney diseases may be at higher risk for death from COVID-19 and may require special care.

Community exposures among Colorado adults who tested positive for SARS-CoV-2 -A case-control study, March-December 2021.

OBJECTIVES: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which causes coronavirus disease 2019 (COVID-19), is spread primarily through exposure to respiratory droplets from close contact with an infected person. To inform prevention measures, we conducted a case-control study among Colorado adults to assess the risk of SARS-CoV-2 infection from community exposures. METHODS: Cases were symptomatic Colorado adults (aged ≥18 years) with a positive SARS-CoV-2 test by reverse transcription-polymerase chain reaction (RT-PCR) reported to Colorado's COVID-19 surveillance system. From March 16 to December 23, 2021, cases were randomly selected from surveillance data ≤12 days after their specimen collection date. Cases were matched on age, zip code (urban areas) or region (rural/frontier areas), and specimen collection date with controls randomly selected among persons with a reported negative SARS-CoV-2 test result. Data on close contact and community exposures were obtained from surveillance and a survey administered online. RESULTS: The most common exposure locations among all cases and controls were place of employment, social events, or gatherings and the most frequently reported exposure relationship was co-worker or friend. Cases were more likely than controls to work outside the home (adjusted odds ratio (aOR) 1.18, 95% confidence interval (CI): 1.09-1.28) in industries and occupations related to accommodation and food services, retail sales, and construction. Cases were also more likely than controls to report contact with a non-household member with confirmed or suspected COVID-19 (aOR 1.16, 95% CI: 1.06-1.27). CONCLUSIONS: Understanding the settings and activities associated with a higher risk of SARS-CoV-2 infection is essential for informing prevention measures aimed at reducing the transmission of SARS-CoV-2 and other respiratory diseases. These findings emphasize the risk of community exposure to infected persons and the need for workplace precautions in preventing ongoing transmission.

Virtual Care and Urinary Tract Infection Management: Comparing Ancillary Service Orders and Patient Order Fulfillments Between Virtual and In-person Encounters During the COVID-19 Pandemic in the United States.

BACKGROUND: During the COVID-19 pandemic, more health care issues were being managed remotely. Urinary tract infections (UTIs) are being managed more often using telehealth although few reports compare the rate of UTI ancillary service orders placed and fulfilled during these visits. OBJECTIVES: We aimed to evaluate and compare the rate of ancillary service orders and order fulfillments in incident UTI diagnoses between virtual and in-person encounters. RESEARCH DESIGN: The retrospective cohort study involved 3 integrated health care systems: Kaiser Permanente (KP) Colorado, KP Georgia, and KP Mid-Atlantic States. SUBJECTS: We included incident UTI encounters from adult primary care data from January 2019 to June 2021. MEASURES: Data were categorized as: prepandemic (January 2019-March 2020), COVID-19 Era 1 (April 2020-June 2020), and COVID-19 Era 2 (July 2020-June 2021). UTI-specific ancillary services included medication, laboratory, and imaging. Orders and order fulfillments were dichotomized for analyses. Weighted percentages for orders and fulfillments were calculated using inverse probability treatment weighting from logistic regression and compared between virtual and in-person encounters using χ2 tests. RESULTS: We identified 123,907 incident encounters. Virtual encounters increased from 13.4% prepandemic to 39.1% in COVID-19 Era 2. Ancillary service orders from virtual encounters were not placed as often as in-person encounters. However, the weighted percentage for ancillary service order fulfillment across all services remained above 65.3% across sites and eras, with many fulfillment percentages above 90%. CONCLUSIONS: Our study reported a high rate of order fulfillment for both virtual and in-person encounters. Health care systems should encourage providers to place ancillary service orders for uncomplicated diagnoses, such as UTI, to provide enhanced access to patient-centered care.

Evaluation of Correctional Facility COVID-19 Outbreaks With Layered Mitigation Strategies Including Vaccination: Colorado, 2020-2021.

In 2020-2021, a Colorado corrections facility experienced four COVID-19 outbreaks. Case counts, attack rates (ARs) in people who are detained or incarcerated (PDI), and mitigation measures used in each outbreak were compared to evaluate effects of combined strategies. Serial PCR testing, isolation/quarantine, and masking were implemented in outbreak 1. Daily staff antigen testing began in outbreak 2. Facility-wide COVID-19 vaccination started in outbreak 3 and coverage increased by the end of outbreak 4 (PDI: <1% to 59%, staff: 27% to 40%). Despite detection of variants of concern, outbreaks 3 and 4 had 97% lower PDI ARs (both 1%) than outbreak 2 (29%). Daily staff testing and increasing vaccination coverage, with other outbreak mitigation strategies, are important to reduce COVID-19 transmission in congregate settings.

The COVID-19-wildfire smoke paradox: Reduced risk of all-cause mortality due to wildfire smoke in Colorado during the first year of the COVID-19 pandemic.

BACKGROUND: In 2020, the American West faced two competing challenges: the COVID-19 pandemic and the worst wildfire season on record. Several studies have investigated the impact of wildfire smoke (WFS) on COVID-19 morbidity and mortality, but little is known about how these two public health challenges impact mortality risk for other causes. OBJECTIVES: Using a time-series design, we evaluated how daily risk of mortality due to WFS exposure differed for periods before and during the COVID-19 pandemic. METHODS: Our study included daily data for 11 counties in the Front Range region of Colorado (2010-2020). We assessed WFS exposure using data from the National Oceanic and Atmospheric Administration and used mortality counts from the Colorado Department of Public Health and Environment. We estimated the interaction between WFS and the pandemic (an indicator variable) on mortality risk using generalized additive models adjusted for year, day of week, fine particulate matter, ozone, temperature, and a smoothed term for day of year. RESULTS: WFS impacted the study area on 10% of county-days. We observed a positive association between the presence of WFS and all-cause mortality risk (incidence rate ratio (IRR) = 1.03, 95%CI: 1.01-1.04 for same-day exposures) during the period before the pandemic; however, WFS exposure during the pandemic resulted in decreased risk of all-cause mortality (IRR = 0.90, 95%CI: 0.87-0.93 for same-day exposures). DISCUSSION: We hypothesize that mitigation efforts during the first year of the pandemic, e.g., mask mandates, along with high ambient WFS levels encouraged health behaviors that reduced exposure to WFS and reduced risk of all-cause mortality. Our results suggest a need to examine how associations between WFS and mortality are impacted by pandemic-related factors and that there may be lessons from the pandemic that could be translated into health-protective policies during future wildfire events.

SARS-CoV-2 Seroprevalence Compared with Confirmed COVID-19 Cases among Children, Colorado, USA, May-July 2021.

To compare SARS-CoV-2 antibody seroprevalence among children with seropositive confirmed COVID-19 case counts (case ascertainment by molecular amplification) in Colorado, USA, we conducted a cross-sectional serosurvey during May-July 2021. For a convenience sample of 829 Colorado children, SARS-CoV-2 seroprevalence was 36.7%, compared with prevalence of 6.5% according to individually matched COVID-19 test results reported to public health. Compared with non-Hispanic White children, seroprevalence was higher among Hispanic, non-Hispanic Black, and non-Hispanic other race children, and case ascertainment was significantly lower among Hispanic and non-Hispanic Black children. This serosurvey accurately estimated SARS-CoV-2 prevalence among children compared with confirmed COVID-19 case counts and revealed substantial racial/ethnic disparities in infections and case ascertainment. Continued efforts to address racial and ethnic differences in disease burden and to overcome potential barriers to case ascertainment, including access to testing, may help mitigate these ongoing disparities.

High rates of observed face mask use at Colorado universities align with students' opinions about masking and support the safety and viability of in-person higher education during the COVID-19 pandemic.

BACKGROUND: Over the course of the COVID-19 pandemic, colleges and universities have focused on creating policies, such as mask mandates, to minimize COVID-19 transmission both on their campuses and in the surrounding community. Adherence to and opinions about these policies remain largely unknown. METHODS: The Centers for Disease Control and Prevention (CDC) developed a cross-sectional study, the Mask Adherence and Surveillance at Colleges and Universities Project (MASCUP!), to objectively and inconspicuously measure rates of mask use at institutes of higher education via direct observation. From February 15 through April 11, 2021 the University of Colorado Boulder (CU, n = 2,808 observations) and Colorado State University Fort Collins (CSU, n = 3,225 observations) participated in MASCUP! along with 52 other institutes of higher education (n = 100,353 observations) spanning 21 states and the District of Columbia. Mask use was mandatory at both Colorado universities and student surveys were administered to assess student beliefs and attitudes. RESULTS: We found that 91.7%, 93.4%, and 90.8% of persons observed at indoor locations on campus wore a mask correctly at University of Colorado, Colorado State University, and across the 52 other schools, respectively. Student responses to questions about masking were in line with these observed rates of mask use where 92.9% of respondents at CU and 89.8% at CSU believe that wearing masks can protect the health of others. Both Colorado universities saw their largest surges in COVID-19 cases in the fall of 2020, with markedly lower case counts during the mask observation window in the spring of 2021. CONCLUSION: High levels of mask use at Colorado's two largest campuses aligned with rates observed at other institutes across the country. These high rates of use, coupled with positive student attitudes about mask use, demonstrate that masks were widely accepted and may have contributed to reduced COVID-19 case counts. This study supports an emerging body of literature substantiating masks as an effective, low-cost measure to reduce disease transmission and establishes masking (with proper education and promotion) as a viable tactic to reduce respiratory disease transmission on college campuses.

Real-world use of nirmatrelvir-ritonavir in outpatients with COVID-19 during the era of omicron variants including BA.4 and BA.5 in Colorado, USA: a retrospective cohort study.

BACKGROUND: Nirmatrelvir is a protease inhibitor with in-vitro activity against SARS-CoV-2, and ritonavir-boosted nirmatrelvir can reduce the risk of progression to severe COVID-19 among individuals at high risk infected with delta and early omicron variants. However, less is known about the effectiveness of nirmatrelvir-ritonavir during more recent BA.2, BA2.12.1, BA.4, and BA.5 omicron variant surges. We used our real-world data platform to evaluate the effect of nirmatrelvir-ritonavir treatment on 28-day hospitalisation, mortality, and emergency department visits among outpatients with early symptomatic COVID-19 during a SARS-CoV-2 omicron (BA.2, BA2.12.1, BA.4, and BA.5) predominant period in Colorado, USA. METHODS: We did a propensity-matched, retrospective, observational cohort study of non-hospitalised adult patients infected with SARS-CoV-2 between March 26 and Aug 25, 2022, using records from a statewide health system in Colorado. We obtained data from the electronic health records of University of Colorado Health, the largest health system in Colorado, with 13 hospitals and 141 000 annual hospital admissions, and with numerous ambulatory sites and affiliated pharmacies around the state. Included patients had a positive SARS-CoV-2 test or nirmatrelvir-ritonavir medication order. Exclusion criteria were an order for or administration of other SARS-CoV-2 treatments within 10 days of a positive SARS-CoV-2 test, hospitalisation at the time of positive SARS-CoV-2 test, and positive SARS-CoV-2 test more than 10 days before a nirmatrelvir-ritonavir order. We propensity score matched patients treated with nirmatrelvir-ritonavir with untreated patients. The primary outcome was 28-day all-cause hospitalisation. FINDINGS: Among 28 167 patients infected with SARS-CoV-2 between March 26 and Aug 25, 2022, 21 493 met the study inclusion criteria. 9881 patients received treatment with nirmatrelvir-ritonavir and 11 612 were untreated. Nirmatrelvir-ritonavir treatment was associated with reduced 28-day all-cause hospitalisation compared with no antiviral treatment (61 [0·9%] of 7168 patients vs 135 [1·4%] of 9361 patients, adjusted odds ratio (OR) 0·45 [95% CI 0·33-0·62]; p<0·0001). Nirmatrelvir-ritonavir treatment was also associated with reduced 28-day all-cause mortality (two [<0·1%] of 7168 patients vs 15 [0·2%] of 9361 patients; adjusted OR 0·15 [95% CI 0·03-0·50]; p=0·0010). Using subsequent emergency department visits as a surrogate for clinically significant relapse, we observed a decrease after nirmatrelvir-ritonavir treatment (283 [3·9%] of 7168 patients vs 437 [4·7%] of 9361 patients; adjusted OR 0·74 [95% CI 0·63-0·87]; p=0·0002). INTERPRETATION: Real-world evidence reported during a BA.2, BA2.12.1, BA.4, and BA.5 omicron surge showed an association between nirmatrelvir-ritonavir treatment and reduced 28-day all-cause hospitalisation, all-cause mortality, and visits to the emergency department. With results that are among the first to suggest effectiveness of nirmatrelvir-ritonavir for non-hospitalised patients during an omicron period inclusive of BA.4 and BA.5 subvariants, these data support nirmatrelvir-ritonavir as an ongoing first-line treatment for adults acutely infected with SARS-CoV-2. FUNDING: US National Institutes of Health.

Correlation between 25-hydroxyvitamin D/D3 Deficiency and COVID-19 Disease Severity in Adults from Northern Colorado.

Vitamin D deficiency is common in the United States and leads to altered immune function, including T cell and macrophage activity that may impact responses to SARS-CoV-2 infection. This study investigated 131 adults with a history of a positive SARS-CoV-2 nasopharyngeal PCR and 18 adults with no COVID-19 diagnosis that were recruited from the community or hospital into the Northern Colorado Coronavirus Biorepository (NoCo-COBIO). Participants consented to enrollment for a period of 6 months and provided biospecimens at multiple visits for longitudinal analysis. Plasma 25-hydroxyvitamin D levels were quantified by LC-MS/MS at the initial visit (n = 149) and after 4 months (n = 89). Adults were classified as deficient (<30 nM or <12 ng/mL), insufficient (<30−50 nM or 12−20 ng/mL), or optimal (50−75 nM or >20 ng/mL) for 25-hydroxyvitamin D status. Fisher's exact test demonstrated an association between disease severity, gender, and body mass index (BMI) at baseline. Mixed model analyses with Tukey-Kramer were used for longitudinal analysis according to BMI. Sixty-nine percent (n = 103) of the entire cohort had optimal levels of total 25(OH)D, 22% (n = 32) had insufficient levels, and 9% (n = 14) had deficent levels. Participants with severe disease (n = 37) had significantly lower 25-hydroxyvitamin D (total 25(OH)D) when compared to adults with mild disease (p = 0.006) or no COVID-19 diagnosis (p = 0.007). There was 44% of the cohort with post-acute sequalae of COVID-19 (PASC) as defined by experiencing at least one of the following symptoms after 60 days' post-infection: fatigue, dyspnea, joint pain, chest pain, forgetfulness or absent-mindedness, confusion, or difficulty breathing. While significant differences were detected in 25-hydroxyvitamin D status by sex and BMI, there were no correlations between 25-hydroxyvitamin D for those without and without PASC. This longitudinal study of COVID-19 survivors demonstrates an important association between sex, BMI, and disease severity for 25-hydroxyvitamin D deficiency during acute stages of infection, yet it is not clear whether supplementation efforts would influence long term outcomes such as developing PASC.

SARS-CoV-2 Infections and Presymptomatic Type 1 Diabetes Autoimmunity in Children and Adolescents From Colorado, USA, and Bavaria, Germany.

This study screens more than 50 000 youths in diverse populations of Colorado and Bavaria to assess whether previous SARS-CoV-2 infection was associated with autoimmunity, which predicts future type 1 diabetes.

Phylodynamics of a regional SARS-CoV-2 rapid spreading event in Colorado in late 2020.

Since the initial reported discovery of SARS-CoV-2 in late 2019, genomic surveillance has been an important tool to understand its transmission and evolution. Here, we sought to describe the underlying regional phylodynamics before and during a rapid spreading event that was documented by surveillance protocols of the United States Air Force Academy (USAFA) in late October-November of 2020. We used replicate long-read sequencing on Colorado SARS-CoV-2 genomes collected July through November 2020 at the University of Colorado Anschutz Medical campus in Aurora and the United States Air Force Academy in Colorado Springs. Replicate sequencing allowed rigorous validation of variation and placement in a phylogenetic relatedness network. We focus on describing the phylodynamics of a lineage that likely originated in the local Colorado Springs community and expanded rapidly over the course of two months in an outbreak within the well-controlled environment of the United States Air Force Academy. Divergence estimates from sampling dates indicate that the SARS-CoV-2 lineage associated with this rapid expansion event originated in late October 2020. These results are in agreement with transmission pathways inferred by the United States Air Force Academy, and provide a window into the evolutionary process and transmission dynamics of a potentially dangerous but ultimately contained variant.

Medication prescribing for alcohol use disorders during alcohol-related encounters in a Colorado regional healthcare system.

RATIONALE: Investigations show that medications for alcohol use disorders (MAUD) reduce heavy drinking and relapses. However, only 1.6% of individuals with alcohol use disorders (AUD) receive MAUD across care settings. The epidemiology of MAUD prescribing in the acute care setting is incompletely described. We hypothesized that MAUD would be under prescribed in inpatient acute care hospital settings compared to the outpatient, emergency department (ED), and inpatient substance use treatment settings. METHODS: We evaluated electronic health record (EHR) data from adult patients with an International Classification of Diseases, 10th revision (ICD-10) alcohol-related diagnosis in the University of Colorado Health (UCHealth) system between January 1, 2016 and 31 December, 2019. Data from patients with an ICD-10 diagnosis code for opioid use disorder and those receiving MAUD prior to their first alcohol-related episode were excluded. The primary outcome was prescribing of MAUD, defined by prescription of naltrexone, acamprosate, and/or disulfiram. We performed bivariate and multivariate analyses to identify independent predictors of MAUD prescribing at UCHealth. RESULTS: We identified 48,421 unique patients with 136,205 alcohol-related encounters at UCHealth. Encounters occurred in the ED (42%), inpatient acute care (17%), inpatient substance use treatment (18%), or outpatient primary care (12%) settings. Only 2270 (5%) patients received MAUD across all settings. Female sex and addiction medicine consults positively predicted MAUD prescribing. In contrast, encounters outside inpatient substance use treatment, Hispanic ethnicity, and black or non-white race were negative predictors of MAUD prescribing. Compared to inpatient substance use treatment, inpatient acute care hospitalizations for AUD was associated with a 93% reduced odds of receiving MAUD. CONCLUSIONS: AUD-related ED and inpatient acute care hospital encounters in our healthcare system were common. Nevertheless, prescriptions for MAUD were infrequent in this population, particularly in inpatient settings. Our findings suggest that the initiation of MAUD for patients with alcohol-related diagnoses in acute care settings deserves additional evaluation.

SARS-CoV-2 infection risk among vaccinated and unvaccinated household members during the Alpha variant surge - Denver, Colorado, and San Diego, California, January-April 2021.

BACKGROUND: COVID-19 vaccination reduces SARS-CoV-2 infection and transmission. However, evidence is emerging on the degree of protection across variants and in high-transmission settings. To better understand the protection afforded by vaccination specifically in a high-transmission setting, we examined household transmission of SARS-CoV-2 during a period of high community incidence with predominant SARS-CoV-2 B.1.1.7 (Alpha) variant, among vaccinated and unvaccinated contacts. METHODS: We conducted a household transmission investigation in San Diego County, California, and Denver, Colorado, during January-April 2021. Households were enrolled if they had at least one person with documented SARS-CoV-2 infection. We collected nasopharyngeal swabs, blood, demographic information, and vaccination history from all consenting household members. We compared infection risks (IRs), RT-PCR cycle threshold values, SARS-CoV-2 culture results, and antibody statuses among vaccinated and unvaccinated household contacts. RESULTS: We enrolled 493 individuals from 138 households. The SARS-CoV-2 variant was identified from 121/138 households (88%). The most common variants were Alpha (75/121, 62%) and Epsilon (19/121, 16%). There were no households with discordant lineages among household members. One fully vaccinated secondary case was symptomatic (13%); the other 5 were asymptomatic (87%). Among unvaccinated secondary cases, 105/108 (97%) were symptomatic. Among 127 households with a single primary case, the IR for household contacts was 45% (146/322; 95% Confidence Interval [CI] 40-51%). The observed IR was higher in unvaccinated (130/257, 49%, 95% CI 45-57%) than fully vaccinated contacts (6/26, 23%, 95% CI 11-42%). A lower proportion of households with a fully vaccinated primary case had secondary cases (1/5, 20%) than households with an unvaccinated primary case (66/108, 62%). CONCLUSIONS: Although SARS-CoV-2 infections in vaccinated household contacts were reported in this high transmission setting, full vaccination protected against SARS-CoV-2 infection. These findings further support the protective effect of COVID-19 vaccination and highlight the need for ongoing vaccination among eligible persons.

Investigation of COVID-19 Outbreak among Wildland Firefighters during Wildfire Response, Colorado, USA, 2020.

A COVID-19 outbreak occurred among Cameron Peak Fire responders in Colorado, USA, during August 2020-January 2021. The Cameron Peak Fire was the largest recorded wildfire in Colorado history, lasting August-December 2020. At least 6,123 responders were involved, including 1,260 firefighters in 63 crews who mobilized to the fire camps. A total of 79 COVID-19 cases were identified among responders, and 273 close contacts were quarantined. State and local public health investigated the outbreak and coordinated with wildfire management teams to prevent disease spread. We performed whole-genome sequencing and applied social network analysis to visualize clusters and transmission dynamics. Phylogenetic analysis identified 8 lineages among sequenced specimens, implying multiple introductions. Social network analysis identified spread between and within crews. Strategies such as implementing symptom screening and testing of arriving responders, educating responders about overlapping symptoms of smoke inhalation and COVID-19, improving physical distancing of crews, and encouraging vaccinations are recommended.

Household Transmission and Symptomology of Severe Acute Respiratory Syndrome Coronavirus 2 Alpha Variant among Children-California and Colorado, 2021.

OBJECTIVE: To assess the household secondary infection risk (SIR) of B.1.1.7 (Alpha) and non-Alpha lineages of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among children. STUDY DESIGN: During January to April 2021, we prospectively followed households with a SARS-CoV-2 infection. We collected questionnaires, serial nasopharyngeal swabs for reverse transcription polymerase chain reaction testing and whole genome sequencing, and serial blood samples for serology testing. We calculated SIRs by primary case age (pediatric vs adult), household contact age, and viral lineage. We evaluated risk factors associated with transmission and described symptom profiles among children. RESULTS: Among 36 households with pediatric primary cases, 21 (58%) had secondary infections. Among 91 households with adult primary cases, 51 (56%) had secondary infections. SIRs among pediatric and adult primary cases were 45% and 54%, respectively (OR, 0.79; 95% CI, 0.41-1.54). SIRs among pediatric primary cases with Alpha and non-Alpha lineage were 55% and 46%, respectively (OR, 1.52; 95% CI, 0.51-4.53). SIRs among pediatric and adult household contacts were 55% and 49%, respectively (OR, 1.01; 95% CI, 0.68-1.50). Among pediatric contacts, no significant differences in the odds of acquiring infection by demographic or household characteristics were observed. CONCLUSIONS: Household transmission of SARS-CoV-2 from children and adult primary cases to household members was frequent. The risk of secondary infection was similar among child and adult household contacts. Among children, household transmission of SARS-CoV-2 and the risk of secondary infection was not influenced by lineage. Continued mitigation strategies (eg, masking, physical distancing, vaccination) are needed to protect at-risk groups regardless of virus lineage circulating in communities.

COVID-19 Surveillance in the Biobank at the Colorado Center for Personalized Medicine: Observational Study.

BACKGROUND: Characterizing the experience and impact of the COVID-19 pandemic among various populations remains challenging due to the limitations inherent in common data sources, such as electronic health records (EHRs) or cross-sectional surveys. OBJECTIVE: This study aims to describe testing behaviors, symptoms, impact, vaccination status, and case ascertainment during the COVID-19 pandemic using integrated data sources. METHODS: In summer 2020 and 2021, we surveyed participants enrolled in the Biobank at the Colorado Center for Personalized Medicine (CCPM; N=180,599) about their experience with COVID-19. The prevalence of testing, symptoms, and impacts of COVID-19 on employment, family life, and physical and mental health were calculated overall and by demographic categories. Survey respondents who reported receiving a positive COVID-19 test result were considered a "confirmed case" of COVID-19. Using EHRs, we compared COVID-19 case ascertainment and characteristics in EHRs versus the survey. Positive cases were identified in EHRs using the International Statistical Classification of Diseases, 10th revision (ICD-10) diagnosis codes, health care encounter types, and encounter primary diagnoses. RESULTS: Of the 25,063 (13.9%) survey respondents, 10,661 (42.5%) had been tested for COVID-19, and of those, 1366 (12.8%) tested positive. Nearly half of those tested had symptoms or had been exposed to someone who was infected. Young adults (18-29 years) and Hispanics were more likely to have positive tests compared to older adults and persons of other racial/ethnic groups. Mental health (n=13,688, 54.6%) and family life (n=12,233, 48.8%) were most negatively affected by the pandemic and more so among younger groups and women; negative impacts on employment were more commonly reported among Black respondents. Of the 10,249 individuals who responded to vaccination questions from version 2 of the survey (summer 2021), 9770 (95.3%) had received the vaccine. After integration with EHR data up to the time of the survey completion, 1006 (4%) of the survey respondents had a discordant COVID-19 case status between EHRs and the survey. Using all longitudinal EHR and survey data, we identified 11,472 (6.4%) COVID-19-positive cases among Biobank participants. In comparison to COVID-19 cases identified through the survey, EHR-identified cases were younger and more likely to be Hispanic. CONCLUSIONS: We found that the COVID-19 pandemic has had far-reaching and varying effects among our Biobank participants. Integrated data assets, such as the Biobank at the CCPM, are key resources for population health monitoring in response to public health emergencies, such as the COVID-19 pandemic.

Geography of Disparity: Connecting COVID-19 Vulnerability and Social Determinants of Health in Colorado.

The COVID-19 pandemic has drawn greater attention to social determinants of health and associated health inequities, which disproportionately affect vulnerable populations and places in the U.S. In this study, we explored geographic patterns of local-level COVID-19 vulnerability and associations with social and health determinants across Colorado. To conceptualize social and health determinants and how together they generate risk and exposure, we integrated the concepts of social vulnerability and syndemic to situate COVID-19 vulnerability within a broader hazards of place framework. Using geospatial statistics and GIS, we estimated census tract-level rates of COVID-19, which are not yet available in Colorado, and mapped areas of high and low incidence risk. We also developed composite indices that characterized social and health vulnerabilities to measure multivariate associations with COVID-19 rates. The findings revealed hotspots of persistent risk in mountain communities since the pandemic emerged in Colorado, as well as clusters of risk in the Urban Front Range's central and southern counties, and across many parts of eastern Colorado. Vulnerability analyses indicate that COVID-19 rates were associated with mental health and chronic conditions along with social determinants that represent inequities in education, income, healthcare access, and race/ethnicity (minority percent of population), which may have disproportionately exposed some communities more than others to infection and severe health outcomes. Overall, the findings provide geographic health information about COVID-19 and vulnerability context, which may better inform local decision-making for interventions and policies that support equity of social determinants of health.Supplemental data for this article is available online at https://doi.org/10.1080/08964289.2021.2021382 .

Lower Prevalence of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Infection Among People Experiencing Homelessness Tested in Outdoor Encampments Compared With Overnight Shelters: Denver, Colorado, June-July 2020.

BACKGROUND: A better understanding of the risk for coronavirus disease 2019 (COVID-19) that people experiencing homelessness (PEH) face in congregate shelters versus unsheltered encampments is critical for an effective pandemic response. METHODS: We analyzed factors associated with current and past severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among PEH in day and overnight shelters and encampments in Denver, Colorado, during June 2-July 28, 2020, and constructed multivariable logistic regression models to examine risk factors for SARS-CoV-2 RNA and seropositivity with age, race/ethnicity, testing location, testing month, and symptom status as predictor variables. RESULTS: A total of 823 participants were tested for SARS-CoV-2 RNA, and 276 individuals were tested for SARS-CoV-2 antibodies. A greater percentage of PEH at overnight shelters tested positive for SARS-CoV-2 RNA (8.6% vs 2.5%, P < .01) and antibodies (21.5% vs 8.7%, P = .03) compared with encampments. In regression models, testing at an overnight shelter compared with testing at encampments (odds ratio [OR] = 3.03, 95% confidence interval [CI]: 1.16-9.02) had increased odds of a positive SARS-CoV-2 RNA result. Age >60 years compared with age <40 years (OR = 5.92; 95% CI: 1.83-20.3), Hispanic ethnicity (OR = 3.43; 95% CI: 1.36-8.95), and non-Hispanic Black race compared with non-Hispanic White race (OR = 3.07; 95% CI: 1.16-8.26), and testing at an overnight shelter compared to testing at encampments (OR = 2.45; 95% CI: 1.04-6.17) had increased odds of a positive antibody result. CONCLUSIONS: Our findings support the need for continuing assessment of mitigation strategies in shelters, increasing access to individual rooms and linkage to housing options for PEH, and supporting people to remain in encampments when these options are not available.

Impact of Coronavirus Disease-19 "Stay-At-Home" Orders on Preterm Birth in Colorado.

In this retrospective cohort analysis of Colorado birth certificate records from April to December 2015-2020, we demonstrate that Colorado birthing individuals experienced lower adjusted odds of preterm birth after issuance of coronavirus-19 "stay-at-home" orders. However, this positive birth outcome was experienced only by non-Hispanic white and Hispanic mothers.