TOPIC: Chest Infections TYPE: Original Investigations PURPOSE: COVID-19 infection is associated with a broad-range of clinical presentations from asymptomatic infection to severe pneumonia with multi-system features. Similarly, short- and long-term outcomes vary widely. Although multiple studies have addressed outcomes of patients hospitalized with COVID-19 infection, Community-based studies are sparse and are needed to provide a broader perspective of the lasting impact of this disease, especially lung damage. METHODS: This is a retrospective, Community-based, cohort study of residents of Rochester, Minnesota, who were enrolled in the Mayo Clinic COVID-19 database. Subjects were included if they were diagnosed with COVID-19 infection from March 01, 2020 to May 31, 2020. The clinical presentation, laboratory results, pulmonary function results, and chest imaging findings at the time of presentation and events in the following months until December 31, 2020 were assessed by review of medical records and imaging studies. RESULTS: We identified 570 community patients with COVID-19 infection;median age 38.5 years (range 18-98 years) - 526 patients did not require hospitalization while 44 (7.5%) patients (median age 51.8 years, range 20 - 81) had hypoxemia warranting admission (moderate to severe disease based on WHO clinical progression scale)[i]. At the time of hospitalization, all has undergone chest radiography, and 42 patients (95%) had chest CT with all demonstrating peripheral patchy ground glass opacities (GGOs) bilaterally.Thirteen patients (29.5%) returned for chest radiograph (median interval, 5.9 months);4 of them (13%) had residual parenchymal opacities, of whom nearly all (94%) were 45 years or older. Twenty-five patients had follow-up CT scans three months after initial diagnosis;8 patients (32%) had complete resolution of the CT infiltrates. Seventeen patients (9 females and 8 males) had residual parenchymal opacities with the most common being peripheral and bibasilar GGOs;5 patients had residual reticulonodular scarring and traction bronchiectasis on imaging. 6 patients (13.6%) underwent pulmonary function testing at follow-up visit (median interval 4.6 months), of whom 2 manifested abnormal findings consisting of mild restriction. Overall, 50% of the patients had evidence of residual lung disease (imaging and/or pulmonary function) three months after presentation. Ten patients (59%) with residual disease on chest CT had been hospitalized (six requiring ICU level of care) and manifested significantly elevated inflammatory markers (ferritin, interleukin-6 and C-reactive protein);9 out of these 10 patients with residual disease did not receive steroids at the time of hospitalization. Seven patients (41%) with residual lung infiltrates on CT scan was not hospitalized and didn’t have evidence of severe inflammatory disease. CONCLUSIONS: In our study, we assessed the initial severity and outcomes of subjects diagnosed with COVID-19 in our community and found 3% to manifest persistent lung abnormalities following the acute infection. The residual radiological findings consisted mainly of GGOs affecting the peripheral zones of the lung;however, in a minority of the patients, fibrotic changes were present. Almost two thirds of the patients with persistently abnormal imaging had been hospitalized for at least two days and had high serologic inflammatory markers (C-reactive protein, Ferritin and interleukin-6). This might indicate that the resultant fibrosis is mainly driven by post-inflammatory processes rather than the direct effect of the virus. conversely a considerable number of patients developed interstitial infiltrates without evidence of acute inflammatory reaction which may suggest another non-inflammatory etiology of these findings. Furthermore, most of our patients who manifested lung fibrosis on follow-up CT had not received steroids. Although the long-term course and significance of these residual radiologic findings are not established, prior data of Middle East Respiratory Syndrome and Se ere Acute Respiratory Syndrome suggest that most of these lesions resolve over time among those who survived hospitalization. CLINICAL IMPLICATIONS: The results of this community-based study will provide a broader perspective of the lasting impact of COVID-19 on the lungs. DISCLOSURES: No relevant relationships by Faysal Al-ghoula, source=Web Response Research - industry initiated (clinical relationship with AstraZeneca Pharmaceuticals, LP Please note: 2020 Added 04/27/2021 by Philippe Bauer, source=Web Response, value=Grant/Research Support Research - industry initiated (clinical relationship with Corvus Pharmaceuticals, Inc Please note: 2021 Added 04/27/2021 by Philippe Bauer, source=Web Response, value=Grant/Research Support No relevant relationships by Eva Carmona, source=Web Response No relevant relationships by Tobias Peikert, source=Web Response No relevant relationships by Jay Ryu, source=Web Response