A capture-recapture modeling framework emphasizing expert opinion in disease surveillance.

In disease surveillance, capture-recapture methods are commonly used to estimate the number of diseased cases in a defined target population. Since the number of cases never identified by any surveillance system cannot be observed, estimation of the case count typically requires at least one crucial assumption about the dependency between surveillance systems. However, such assumptions are generally unverifiable based on the observed data alone. In this paper, we advocate a modeling framework hinging on the choice of a key population-level parameter that reflects dependencies among surveillance streams. With the key dependency parameter as the focus, the proposed method offers the benefits of (a) incorporating expert opinion in the spirit of prior information to guide estimation; (b) providing accessible bias corrections, and (c) leveraging an adapted credible interval approach to facilitate inference. We apply the proposed framework to two real human immunodeficiency virus surveillance datasets exhibiting three-stream and four-stream capture-recapture-based case count estimation. Our approach enables estimation of the number of human immunodeficiency virus positive cases for both examples, under realistic assumptions that are under the investigator's control and can be readily interpreted. The proposed framework also permits principled uncertainty analyses through which a user can acknowledge their level of confidence in assumptions made about the key non-identifiable dependency parameter.

Rapid, high throughput, automated detection of SARS-CoV-2 neutralizing antibodies against Wuhan-WT, delta and omicron BA1, BA2 spike trimers.

Traditional cellular and live-virus methods for detection of SARS-CoV-2 neutralizing antibodies (nAbs) are labor- and time-intensive, and thus not suited for routine use in the clinical lab to predict vaccine efficacy and natural immune protection. Here, we report the development and validation of a rapid, high throughput method for measuring SARS-CoV-2 nAbs against native-like trimeric spike proteins. This assay uses a blockade of human angiotensin converting enzyme 2 (hACE-2) binding (BoAb) approach in an automated digital immunoassay on the Quanterix HD-X platform. BoAb assays using Wuhan-WT (vaccine strain), delta (B.1.167.2), omicron BA1 and BA2 variant viral strains showed strong correlation with cell-based pseudovirus neutralization activity (PNA) and live-virus neutralization activity. Importantly, we were able to detect similar patterns of delta and omicron variant resistance to neutralization in samples with paired vaccine strain and delta variant BoAb measurements. Finally, we screened clinical samples from patients with or without evidence of SARS-CoV-2 exposure by a single-dilution screening version of our assays, finding significant nAb activity only in exposed individuals. Importantly, this completely automated assay can be performed in 4 h to measure neutralizing antibody titers for 16 samples over 8 serial dilutions or, 128 samples at a single dilution with replicates. In principle, these assays offer a rapid, robust, and scalable alternative to time-, skill-, and cost-intensive standard methods for measuring SARS-CoV-2 nAb levels.

Use of surveillance data to elucidate household clustering of SARS-CoV-2 in Fulton County, Georgia a major metropolitan area.

BACKGROUND: Households are important for SARS-CoV-2 transmission due to high intensity exposure in enclosed spaces over prolonged durations. We quantified and characterized household clustering of COVID-19 cases in Fulton County, Georgia. METHODS: We used surveillance data to identify all confirmed COVID-19 cases in Fulton County. Household clustered cases were defined as cases with matching residential address. We described the proportion of COVID-19 cases that were clustered, stratified by age over time and explore trends in age of first diagnosed case within households and subsequent household cases. RESULTS: Between June 1, 2020 and October 31, 2021, 31,449(37%) of 106,233 cases were clustered in households. Children were the most likely to be in household clusters than any other age group. Initially, children were rarely (∼ 10%) the first cases diagnosed in the household but increased to almost 1 of 3 in later periods. DISCUSSION: One-third of COVID-19 cases in Fulton County were part of a household cluster. Increasingly children were the first diagnosed case, coinciding with temporal trends in vaccine roll-out among the elderly and the return to in-person schooling in Fall 2021. Limitations include restrictions to cases with a valid address and unit number and that the first diagnosed case may not be the infection source for the household.

Toward Ending the HIV Epidemic: Temporal Trends and Disparities in Early ART Initiation and Early Viral Suppression Among People Newly Entering HIV Care in the United States, 2012-2018.

Background: In 2012, the US Department of Health and Human Services updated their HIV treatment guidelines to recommend antiretroviral therapy (ART) for all people with HIV (PWH) regardless of CD4 count. We investigated recent trends and disparities in early receipt of ART prescription and subsequent viral suppression (VS). Methods: We examined data from ART-naïve PWH newly presenting to HIV care at 13 North American AIDS Cohort Collaboration on Research and Design clinical cohorts in the United States during 2012-2018. We calculated the cumulative incidence of early ART (within 30 days of entry into care) and early VS (within 6 months of ART initiation) using the Kaplan-Meier survival function. Discrete time-to-event models were fit to estimate unadjusted and adjusted associations of early ART and VS with sociodemographic and clinical factors. Results: Among 11 853 eligible ART-naïve PWH, the cumulative incidence of early ART increased from 42% in 2012 to 82% in 2018. The cumulative incidence of early VS among the 8613 PWH who initiated ART increased from 83% in 2012 to 93% in 2018. In multivariable models, factors independently associated with delayed ART and VS included non-Hispanic/Latino Black race, residence in the South census region, being a male with injection drug use acquisition risk, and history of substance use disorder (SUD; all P ≤ .05). Conclusions: Early ART initiation and VS have substantially improved in the United States since the release of universal treatment guidelines. Disparities by factors related to social determinants of health and SUD demand focused attention on and services for some subpopulations.

The Role of Staff in Transmission of SARS-CoV-2 in Long-term Care Facilities.

BACKGROUND: US long-term care facilities (LTCFs) have experienced a disproportionate burden of COVID-19 morbidity and mortality. METHODS: We examined SARS-CoV-2 transmission among residents and staff in 60 LTCFs in Fulton County, Georgia, from March 2020 to September 2021. Using the Wallinga-Teunis method to estimate the time-varying reproduction number, R(t), and linear-mixed regression models, we examined associations between case characteristics and R(t). RESULTS: Case counts, outbreak size and duration, and R(t) declined rapidly and remained low after vaccines were first distributed to LTCFs in December 2020, despite increases in community incidence in summer 2021. Staff cases were more infectious than resident cases (average individual reproduction number, R i = 0.6 [95% confidence intervals [CI] = 0.4, 0.7] and 0.1 [95% CI = 0.1, 0.2], respectively). Unvaccinated resident cases were more infectious than vaccinated resident cases (R i = 0.5 [95% CI = 0.4, 0.6] and 0.2 [95% CI = 0.0, 0.8], respectively), but estimates were imprecise. CONCLUSIONS: COVID-19 vaccines slowed transmission and contributed to reduced caseload in LTCFs. However, due to data limitations, we were unable to determine whether breakthrough vaccinated cases were less infectious than unvaccinated cases. Staff cases were six times more infectious than resident cases, consistent with the hypothesis that staff were the primary drivers of SARS-CoV-2 transmission in LTCFs.

Rapid, high throughput, automated detection of SARS-CoV-2 neutralizing antibodies against native-like vaccine and delta variant spike trimers.

Traditional cellular and live-virus methods for detection of SARS-CoV-2 neutralizing antibodies (nAbs) are labor- and time-intensive, and thus not suited for routine use in the clinical lab to predict vaccine efficacy and natural immune protection. Here, we report the development and validation of a rapid, high throughput method for measuring SARS-CoV-2 nAbs against native-like trimeric spike proteins. This assay uses a blockade of hACE-2 binding (BoAb) approach in an automated digital immunoassay on the Quanterix HD-X platform. BoAb assays using vaccine and delta variant viral strains showed strong correlation with cell-based pseudovirus and live-virus neutralization activity. Importantly, we were able to detect similar patterns of delta variant resistance to neutralization in samples with paired vaccine and delta variant BoAb measurements. Finally, we screened clinical samples from patients with or without evidence of SARS-CoV-2 exposure by a single-dilution screening version of our assays, finding significant nAb activity only in exposed individuals. In principle, these assays offer a rapid, robust, and scalable alternative to time-, skill-, and cost-intensive standard methods for measuring SARS-CoV-2 nAb levels.

Rapid, high throughput, automated detection of SARS-CoV-2 neutralizing antibodies against native-like vaccine and delta variant spike trimers.

Traditional cellular and live-virus methods for detection of SARS-CoV-2 neutralizing antibodies (nAbs) are labor- and time-intensive, and thus not suited for routine use in the clinical lab to predict vaccine efficacy and natural immune protection. Here, we report the development and validation of a rapid, high throughput method for measuring SARS-CoV-2 nAbs against native-like trimeric spike proteins. This assay uses a blockade of hACE-2 binding (BoAb) approach in an automated digital immunoassay on the Quanterix HD-X platform. BoAb assays using vaccine and delta variant viral strains showed strong correlation with cell-based pseudovirus and live-virus neutralization activity. Importantly, we were able to detect similar patterns of delta variant resistance to neutralization in samples with paired vaccine and delta variant BoAb measurements. Finally, we screened clinical samples from patients with or without evidence of SARS-CoV-2 exposure by a single-dilution screening version of our assays, finding significant nAb activity only in exposed individuals. In principle, these assays offer a rapid, robust, and scalable alternative to time-, skill-, and cost-intensive standard methods for measuring SARS-CoV-2 nAb levels.

Implementation of close contact elicitation at the time of COVID-19 testing-Atlanta, GA, October-November 2020.

BACKGROUND: Contact tracing during the Coronavirus Disease 2019 (COVID-19) pandemic in the USA has been met with various challenges. In an attempt to improve the yield of close contact collection, the Fulton County Board of Health implemented a pilot approach to contact elicitation at the time of testing. METHODS: Between October and November 2020, close contacts were elicited from persons under investigation (PUIs) at one COVID-19 testing site in Fulton County, GA. Secure online data collection forms were used to record PUI demographic data, close contact information and reasons for not providing contacts. RESULTS: Of 1238 PUIs, 48% reported at least one contact. Among the 66 people who tested positive, 16 (24%) reported contacts compared to 578/1165 (50%) who tested negative. PUIs of increasing age were less likely to provide contacts; Black and Hispanic PUIs were also less likely to report any contacts compared to White and Asian PUIs. CONCLUSIONS: Our study revealed that PUIs testing positive were less likely to provide contacts compared to PUIs testing negative. Age and racial differences were also noted in the provision of contacts. Further investigation is needed to understand these discrepancies in order to devise more effective strategies for contact elicitation.

Novel polymer-based system for intrauterine delivery of everolimus for anti-cancer applications.

Non-surgical treatment options for low-grade endometrial cancer and precancerous lesions are a critical unmet need for women who wish to preserve fertility or are unable to undergo hysterectomy. The PI3K/AKT/mTOR pathway is frequently activated in endometrial cancers and has been associated with resistance to endocrine therapy, making it a compelling target for early stage disease. Oral everolimus, an inhibitor against mTORC1, has shown clinical benefit in advanced or recurrent disease but has severe adverse effects that may lead to treatment interruption or dose reduction. To overcome this, we developed a polymer-based intrauterine delivery system to achieve persistent, local delivery of everolimus without systemic exposure. In vivo studies, using a rat model, showed that a poly(propylene fumarate)-based rod loaded with everolimus achieved everolimus delivery to the endometrium with levels similar to oral administration, but with limited systemic exposure and up to 84 days of release. Biological activity of everolimus delivered with this system was confirmed, measured by reduced lumen epithelial cell height and PI3K pathway biomarkers. This study shows a promising new delivery approach for anti-cancer drugs for non-surgical treatment of low-grade endometrial cancer.

Antiretroviral hair levels, self-reported adherence, and virologic failure in second-line regimen patients in resource-limited settings.

OBJECTIVE: To evaluate associations between hair antiretroviral hair concentrations as an objective, cumulative adherence metric, with self-reported adherence and virologic outcomes. DESIGN: Analysis of cohort A of the ACTG-A5288 study. These patients in resource-limited settings were failing second-line protease inhibitor-based antiretroviral therapy (ART) but were susceptible to at least one nucleoside reverse transcriptase inhibitor (NRTI) and their protease inhibitor, and continued taking their protease inhibitor-based regimen. METHODS: Antiretroviral hair concentrations in participants taking two NRTIs with boosted atazanavir (n = 69) or lopinavir (n = 112) were analyzed at weeks 12, 24, 36 and 48 using liquid-chromatography--tandem-mass-spectrometry assays. Participants' self-reported percentage of doses taken in the previous month; virologic failure was confirmed HIV-1 RNA at least 1000 copies/ml at week 24 or 48. RESULTS: From 181 participants with hair samples (61% women, median age: 39 years; CD4+ cell count: 167 cells/µl; HIV-1 RNA: 18 648 copies/ml), 91 (50%) experienced virologic failure at either visit. At 24 weeks, median hair concentrations were 2.95 [interquartile range (IQR) 0.49-4.60] ng/mg for atazanavir, 2.64 (IQR 0.73--7.16) for lopinavir, and 0.44 (IQR 0.11--0.76) for ritonavir. Plasma HIV-1 RNA demonstrated inverse correlations with hair levels (rs -0.46 to -0.74) at weeks 24 and 48. Weaker associations were seen with self-reported adherence (rs -0.03 to -0.24). Decreasing hair concentrations were significantly associated with virologic failure, the hazard ratio (95% CI) for ATV, LPV, and RTV were 0.69 (0.56-0.86), 0.77 (0.68-0.87), and 0.12 (0.06-0.27), respectively. CONCLUSION: Protease inhibitor hair concentrations showed stronger associations with subsequent virologic outcomes than self-reported adherence in this cohort. Hair adherence measures could identify individuals at risk of second-line treatment failure in need of interventions.

Rapid Scale-up of an Antiretroviral Therapy Program Before and During the COVID-19 Pandemic - Nine States, Nigeria, March 31, 2019-September 30, 2020.

In 2018, an estimated 1.8 million persons living in Nigeria had HIV infection (1.3% of the total population), including 1.1 million (64%) who were receiving antiretroviral therapy (ART) (1). Effective ART reduces morbidity and mortality rates among persons with HIV infection and prevents HIV transmission once viral load is suppressed to undetectable levels (2,3). In April 2019, through the U.S. President's Emergency Plan for AIDS Relief (PEPFAR),* CDC launched an 18-month ART Surge program in nine Nigerian states to rapidly increase the number of persons with HIV infection receiving ART. CDC analyzed programmatic data gathered during March 31, 2019-September 30, 2020, to describe the ART Surge program's progress on case finding, ART initiation, patient retention, and ART Surge program growth. Overall, the weekly number of newly identified persons with HIV infection who initiated ART increased approximately eightfold, from 587 (week ending May 4, 2019) to 5,329 (week ending September 26, 2020). The ART Surge program resulted in 208,202 more HIV-infected persons receiving PEPFAR-supported ART despite the COVID-19 pandemic (97,387 more persons during March 31, 2019-March 31, 2020 and an additional 110,815 persons during April 2020-September 2020). Comprehensive, data-guided, locally adapted interventions and the use of incident command structures can help increase the number of persons with HIV infection who receive ART, reducing HIV-related morbidity and mortality as well as decreasing HIV transmission.

Retrospective cohort study of COVID-19 among children in Fulton County, Georgia, March 2020-June 2021.

OBJECTIVE: To describe case rates, testing rates and percent positivity of COVID-19 among children aged 0-18 years by school-age grouping. DESIGN: We abstracted data from Georgia's State Electronic Notifiable Disease Surveillance System on all 10 437 laboratory-confirmed COVID-19 cases among children aged 0-18 years during 30 March 2020 to 6 June 2021. We examined case rates, testing rates and percent positivity by school-aged groupings, namely: preschool (0-4 years), elementary school (5-10 years), middle school (11-13 years), and high school (14-18 years) and compared these data among school-aged children with those in the adult population (19 years and older). SETTING: Fulton County, Georgia. MAIN OUTCOME MEASURES: COVID-19 case rates, testing rates and percent positivity. RESULTS: Over time, the proportion of paediatric cases rose substantially from 1.1% (April 2020) to 21.6% (April 2021) of all cases in the county. Age-specific case rates and test rates were consistently highest among high-school aged children. Test positivity was similar across school-age groups, with periods of higher positivity among high-school aged children. CONCLUSIONS: Low COVID-19 testing rates among children, especially early in the pandemic, likely underestimated the true burden of disease in this age group. Despite children having lower measured incidence of COVID-19, we found when broader community incidence increased, incidence also increased among all paediatric age groups. As the COVID-19 pandemic continues to evolve, it remains critical to continue learning about the incidence and transmissibility of COVID-19 in children.

Coronavirus Disease 2019 (COVID-19) Prevalences Among People Experiencing Homelessness and Homelessness Service Staff During Early Community Transmission in Atlanta, Georgia, April-May 2020.

BACKGROUND: In response to reported coronavirus disease 2019 (COVID-19) outbreaks among people experiencing homelessness (PEH) in other US cities, we conducted multiple, proactive, facility-wide testing events for PEH living sheltered and unsheltered and homelessness service staff in Atlanta, Georgia. We describe the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) prevalence and associated symptoms, and review shelter infection prevention and control (IPC) policies. METHODS: PEH and staff were tested for SARS-CoV-2 by reverse transcription polymerase chain reaction (RT-PCR) during 7 April-6 May 2020. A subset of PEH and staff was screened for symptoms. Shelter assessments were conducted concurrently at a convenience sample of shelters using a standardized questionnaire. RESULTS: Overall, 2875 individuals at 24 shelters and 9 unsheltered outreach events underwent SARS-CoV-2 testing, and 2860 (99.5%) had conclusive test results. The SARS-CoV-2 prevalences were 2.1% (36/1684) among PEH living sheltered, 0.5% (3/628) among PEH living unsheltered, and 1.3% (7/548) among staff. Reporting fever, cough, or shortness of breath in the last week during symptom screening was 14% sensitive and 89% specific for identifying COVID-19 cases, compared with RT-PCR. Prevalences by shelter ranged 0-27.6%. Repeat testing 3-4 weeks later at 4 shelters documented decreased SARS-CoV-2 prevalences (0-3.9%). Of 24 shelters, 9 completed shelter assessments and implemented IPC measures as part of the COVID-19 response. CONCLUSIONS: PEH living in shelters experienced a higher SARS-CoV-2 prevalence compared with PEH living unsheltered. Facility-wide testing in congregate settings allowed for the identification and isolation of COVID-19 cases, and is an important strategy to interrupt SARS-CoV-2 transmission.

Estimating the Unknown: Greater Racial and Ethnic Disparities in COVID-19 Burden After Accounting for Missing Race and Ethnicity Data.

BACKGROUND: Black, Hispanic, and Indigenous persons in the United States have an increased risk of SARS-CoV-2 infection and death from COVID-19, due to persistent social inequities. However, the magnitude of the disparity is unclear because race/ethnicity information is often missing in surveillance data. METHODS: We quantified the burden of SARS-CoV-2 notification, hospitalization, and case fatality rates in an urban county by racial/ethnic group using combined race/ethnicity imputation and quantitative bias analysis for misclassification. RESULTS: The ratio of the absolute racial/ethnic disparity in notification rates after bias adjustment, compared with the complete case analysis, increased 1.3-fold for persons classified Black and 1.6-fold for those classified Hispanic, in reference to classified White persons. CONCLUSIONS: These results highlight that complete case analyses may underestimate absolute disparities in notification rates. Complete reporting of race/ethnicity information is necessary for health equity. When data are missing, quantitative bias analysis methods may improve estimates of racial/ethnic disparities in the COVID-19 burden.

COVID-19 Infection Prevention and Control Adherence in Long-Term Care Facilities, Atlanta, Georgia.

BACKGROUND/OBJECTIVE: Recommendations for infection prevention and control (IPC) of COVID-19 in long-term care settings were developed based on limited understanding of COVID-19 and should be evaluated to determine their efficacy in reducing transmission among high-risk populations. DESIGN AND SETTING: Site visits to 24 long-term care facilities (LTCFs) in Fulton County, Georgia, were conducted between June and July 2020 to assess adherence to current guidelines, provide real-time feedback on potential weaknesses, and identify specific indicators whose implementation or lack thereof was associated with higher or lower prevalence of COVID-19. PARTICIPANTS: Twenty-four LTCFs were visited, representing 2,580 LTCF residents, among whom 1,004 (39%) were infected with COVID-19. MEASUREMENTS: Overall IPC adherence in LTCFs was analyzed for 33 key indicators across five categories: Hand Hygiene, Disinfection, Social Distancing, PPE, and Symptom Screening. Facilities were divided into Higher- and Lower-prevalence groups based on cumulative COVID-19 infection prevalence to determine differences in IPC implementation. RESULTS: IPC implementation was lowest in the Disinfection category (32%) and highest in the Symptom Screening category (74%). Significant differences in IPC implementation between the Higher- and Lower-prevalence groups were observed in the Social Distancing category (Higher-prevalence group 54% vs Lower-prevalence group 74%, P < .01) and the PPE category (Higher-prevalence group 41% vs Lower-prevalence group 72%, P < .01). CONCLUSION: LTCFs with lower COVID-19 prevalence among residents had significantly greater implementation of IPC recommendations compared to those with higher COVID-19 prevalence, suggesting the utility in adhering to current guidelines to reduce transmission in this vulnerable population.

Characteristics and Risk Factors for Hospitalization and Mortality among Persons with COVID-19 in Atlanta Metropolitan Area.

Background: We present data on risk factors for severe outcomes among patients with coronavirus disease 2019 (COVID-19) in the southeast United States (U.S.). Objective: To determine risk factors associated with hospitalization, intensive care unit (ICU) admission, and mortality among patients with confirmed COVID-19. Design: A retrospective cohort study. Setting: Fulton County in Atlanta Metropolitan Area, Georgia, U.S. Patients: Community-based individuals of all ages that tested positive for SARS-CoV-2. Measurements: Demographic characteristics, comorbid conditions, hospitalization, ICU admission, death (all-cause mortality), and severe COVID-19 disease, defined as a composite measure of hospitalization and death. Results: Between March 2 and May 31, 2020, we included 4322 individuals with various COVID-19 outcomes. In a multivariable logistic regression random-effects model, patients in age groups ≥45 years compared to those <25 years were associated with severe COVID-19. Males compared to females (adjusted odds ratio [aOR] 1.4, 95% confidence interval [CI]: 1.1-1.6), non-Hispanic blacks (aOR 1.9, 95%CI: 1.5-2.4) and Hispanics (aOR 1.7, 95%CI: 1.2-2.5) compared to non-Hispanic whites were associated with increased odds of severe COVID-19. Those with chronic renal disease (aOR 3.6, 95%CI: 2.2-5.8), neurologic disease (aOR 2.8, 95%CI: 1.8-4.3), diabetes (aOR 2.0, 95%CI: 1.5-2.7), chronic lung disease (aOR 1.7, 95%CI: 1.2-2.3), and "other chronic diseases" (aOR 1.8, 95%CI: 1.3-2.6) compared to those without these conditions were associated with increased odds of having severe COVID-19. Conclusions: Multiple risk factors for hospitalization, ICU admission, and death were observed in this cohort from an urban setting in the southeast U.S. Improved screening and early, intensive treatment for persons with identified risk factors is urgently needed to reduce COVID-19 related morbidity and mortality.

Measuring the missing: greater racial and ethnic disparities in COVID-19 burden after accounting for missing race/ethnicity data.

Black, Hispanic, and Indigenous persons in the United States have an increased risk of SARS-CoV-2 infection and death from COVID-19, due to persistent social inequities. The magnitude of the disparity is unclear, however, because race/ethnicity information is often missing in surveillance data. In this study, we quantified the burden of SARS-CoV-2 infection, hospitalization, and case fatality rates in an urban county by racial/ethnic group using combined race/ethnicity imputation and quantitative bias-adjustment for misclassification. After bias-adjustment, the magnitude of the absolute racial/ethnic disparity, measured as the difference in infection rates between classified Black and Hispanic persons compared to classified White persons, increased 1.3-fold and 1.6-fold respectively. These results highlight that complete case analyses may underestimate absolute disparities in infection rates. Collecting race/ethnicity information at time of testing is optimal. However, when data are missing, combined imputation and bias-adjustment improves estimates of the racial/ethnic disparities in the COVID-19 burden.

Preventing COVID-19 Outbreaks in Long-Term Care Facilities Through Preemptive Testing of Residents and Staff Members - Fulton County, Georgia, March-May 2020.

Long-term care facility (LTCF) residents are at particularly high risk for morbidity and mortality associated with infection with SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), given their age and high prevalence of chronic medical conditions, combined with functional impairment that often requires frequent, close contact with health care providers, who might inadvertently spread the virus to residents (1,2). During March-May 2020 in Fulton County, Georgia, >50% of COVID-19-associated deaths occurred among LTCF residents, although these persons represented <1% of the population (3,4). Mass testing for SARS-CoV-2 has been an effective strategy for identifying asymptomatic and presymptomatic infections in LTCFs (5). This analysis sought to evaluate the timing at which mass testing took place in relation to the known presence of a COVID-19 infection and the resulting number of infections that occurred. In 15 LTCFs that performed facility-wide testing in response to an identified case, high prevalences of additional cases in residents and staff members were found at initial testing (28.0% and 7.4%, respectively), suggesting spread of infection had already occurred by the time the first case was identified. Prevalence was also high during follow-up, with a total of 42.4% of residents and 11.8% of staff members infected overall in the response facilities. In comparison, 13 LTCFs conducted testing as a preventive strategy before a case was identified. Although the majority of these LTCFs identified at least one COVID-19 case, the prevalence was significantly lower at initial testing in both residents and staff members (0.5% and 1.0%, respectively) and overall after follow-up (1.5% and 1.7%, respectively). These findings indicate that early awareness of infections might help facilities prevent potential outbreaks by prioritizing and adhering more strictly to infection prevention and control (IPC) recommendations, resulting in fewer infections than would occur when relying on symptom-based screening (6,7).

Mass Screening for SARS-CoV-2 Infection among Residents and Staff in Twenty-eight Long-term Care Facilities in Fulton County, Georgia.

Mass screening for SARS-CoV-2 infection in long-term care facilities revealed significantly higher prevalence of infection in facilities that screened in response to a known infection compared to those that screened as a prevention measure. "Response" facilities had a SARS-CoV-2 prevalence of 28.9% while "preventive" facilities' prevalence was 1.6% (p <0.001).

Localized mandibular infection affects remote in vivo bioreactor bone generation.

Mandibular reconstruction requires functional and aesthetic repair and is further complicated by contamination from oral and skin flora. Antibiotic-releasing porous space maintainers have been developed for the local release of vancomycin and to promote soft tissue attachment. In this study, mandibular defects in six sheep were inoculated with 106 colony forming units of Staphylococcus aureus; three sheep were implanted with unloaded porous space maintainers and three sheep were implanted with vancomycin-loaded space maintainers within the defect site. During the same surgery, 3D-printed in vivo bioreactors containing autograft or xenograft were implanted adjacent to rib periosteum. After 9 weeks, animals were euthanized, and tissues were analyzed. Antibiotic-loaded space maintainers were able to prevent dehiscence of soft tissue overlying the space maintainer, reduce local inflammatory cells, eliminate the persistence of pathogens, and prevent the increase in mandibular size compared to unloaded space maintainers in this sheep model. Animals with an untreated mandibular infection formed bony tissues with greater density and maturity within the distal bioreactors. Additionally, tissues grown in autograft-filled bioreactors had higher compressive moduli and higher maximum screw pull-out forces than xenograft-filled bioreactors. In summary, we demonstrated that antibiotic-releasing space maintainers are an innovative approach to preserve a robust soft tissue pocket while clearing infection, and that local infections can increase local and remote bone growth.