Investigation of a Severe Acute Respiratory Syndrome Coronavirus 2 Delta (B.1.617.2) Variant Outbreak Among Residents of a Skilled Nursing Facility and Vaccine Effectiveness Analysis: Maricopa County, Arizona, June-July 2021.
Ariella P Dale, Olivia Almendares, Brandon J Howard, Eleanor Burnett, Siru Prasai, Melissa Arons, Jennifer Collins, Nadezdha Duffy, Urvashi Pandit, Shane Brady, Jessica R White, Brenna Garrett, Hannah L Kirking, Rebecca Sunenshine, Jacqueline E Tate, Sarah E Scott
{"title":"Investigation of a Severe Acute Respiratory Syndrome Coronavirus 2 Delta (B.1.617.2) Variant Outbreak Among Residents of a Skilled Nursing Facility and Vaccine Effectiveness Analysis: Maricopa County, Arizona, June-July 2021.","authors":"Ariella P Dale, Olivia Almendares, Brandon J Howard, Eleanor Burnett, Siru Prasai, Melissa Arons, Jennifer Collins, Nadezdha Duffy, Urvashi Pandit, Shane Brady, Jessica R White, Brenna Garrett, Hannah L Kirking, Rebecca Sunenshine, Jacqueline E Tate, Sarah E Scott","doi":"10.1093/cid/ciac240","DOIUrl":null,"url":null,"abstract":"<p><strong>Background: </strong>Short-term rehabilitation units present unique infection control challenges because of high turnover and medically complex residents. In June 2021, the Maricopa County Department of Public Health was notified of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta outbreak in a skilled nursing facility short-term rehabilitation unit. We describe the outbreak and assess vaccine effectiveness (VE).</p><p><strong>Methods: </strong>Facility electronic medical records were reviewed for residents who spent > 1 night on the affected unit between June 10 and July 23, 2021, to collect demographics, SARS-CoV-2 test results, underlying medical conditions, vaccination status, and clinical outcomes. Coronavirus disease 2019 VE estimates using Cox proportional hazards models were calculated.</p><p><strong>Results: </strong>Forty (37%) of 109 short-stay rehabilitation unit residents who met inclusion criteria tested positive for SARS-CoV-2. SARS-CoV-2-positive case-patients were mostly male (58%) and White (78%) with a median age of 65 (range, 27-92) years; 11 (27%) were immunocompromised. Of residents, 39% (10 cases, 32 noncases) received 2 doses and 9% (4 cases, 6 noncases) received 1 dose of messenger RNA (mRNA) vaccine. Among nonimmunocompromised residents, adjusted 2-dose primary-series mRNA VE against symptomatic infection was 80% (95% confidence interval, 15-95). More cases were hospitalized (33%) or died (38%) than noncases (10% hospitalized; 16% died).</p><p><strong>Conclusions: </strong>In this large SARS-CoV-2 Delta outbreak in a high-turnover short-term rehabilitation unit, a low vaccination rate and medically complex resident population were noted alongside severe outcomes. VE of 2-dose primary-series mRNA vaccine against symptomatic infection was the highest in nonimmunocompromised residents. Health departments can use vaccine coverage data to prioritize facilities for assistance in preventing outbreaks.</p>","PeriodicalId":10421,"journal":{"name":"Clinical Infectious Diseases: An Official Publication of the Infectious Diseases Society of America","volume":null,"pages":null},"PeriodicalIF":0.0000,"publicationDate":"2022-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9047249/pdf/","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Clinical Infectious Diseases: An Official Publication of the Infectious Diseases Society of America","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1093/cid/ciac240","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
Background: Short-term rehabilitation units present unique infection control challenges because of high turnover and medically complex residents. In June 2021, the Maricopa County Department of Public Health was notified of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Delta outbreak in a skilled nursing facility short-term rehabilitation unit. We describe the outbreak and assess vaccine effectiveness (VE).
Methods: Facility electronic medical records were reviewed for residents who spent > 1 night on the affected unit between June 10 and July 23, 2021, to collect demographics, SARS-CoV-2 test results, underlying medical conditions, vaccination status, and clinical outcomes. Coronavirus disease 2019 VE estimates using Cox proportional hazards models were calculated.
Results: Forty (37%) of 109 short-stay rehabilitation unit residents who met inclusion criteria tested positive for SARS-CoV-2. SARS-CoV-2-positive case-patients were mostly male (58%) and White (78%) with a median age of 65 (range, 27-92) years; 11 (27%) were immunocompromised. Of residents, 39% (10 cases, 32 noncases) received 2 doses and 9% (4 cases, 6 noncases) received 1 dose of messenger RNA (mRNA) vaccine. Among nonimmunocompromised residents, adjusted 2-dose primary-series mRNA VE against symptomatic infection was 80% (95% confidence interval, 15-95). More cases were hospitalized (33%) or died (38%) than noncases (10% hospitalized; 16% died).
Conclusions: In this large SARS-CoV-2 Delta outbreak in a high-turnover short-term rehabilitation unit, a low vaccination rate and medically complex resident population were noted alongside severe outcomes. VE of 2-dose primary-series mRNA vaccine against symptomatic infection was the highest in nonimmunocompromised residents. Health departments can use vaccine coverage data to prioritize facilities for assistance in preventing outbreaks.