Last data update: Apr 22, 2024. (Total: 46599 publications since 2009)
Records 1-30 (of 32 Records) |
Query Trace: Kirking Hannah[original query] |
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Initial public health response and interim clinical guidance for the 2019 novel coronavirus outbreak - United States, December 31, 2019-February 4, 2020.
Patel A , Jernigan DB , 2019-nCOV CDC Response Team , Abdirizak Fatuma , Abedi Glen , Aggarwal Sharad , Albina Denise , Allen Elizabeth , Andersen Lauren , Anderson Jade , Anderson Megan , Anderson Tara , Anderson Kayla , Bardossy Ana Cecilia , Barry Vaughn , Beer Karlyn , Bell Michael , Berger Sherri , Bertulfo Joseph , Biggs Holly , Bornemann Jennifer , Bornstein Josh , Bower Willie , Bresee Joseph , Brown Clive , Budd Alicia , Buigut Jennifer , Burke Stephen , Burke Rachel , Burns Erin , Butler Jay , Cantrell Russell , Cardemil Cristina , Cates Jordan , Cetron Marty , Chatham-Stephens Kevin , Chatham-Stevens Kevin , Chea Nora , Christensen Bryan , Chu Victoria , Clarke Kevin , Cleveland Angela , Cohen Nicole , Cohen Max , Cohn Amanda , Collins Jennifer , Conners Erin , Curns Aaron , Dahl Rebecca , Daley Walter , Dasari Vishal , Davlantes Elizabeth , Dawson Patrick , Delaney Lisa , Donahue Matthew , Dowell Chad , Dyal Jonathan , Edens William , Eidex Rachel , Epstein Lauren , Evans Mary , Fagan Ryan , Farris Kevin , Feldstein Leora , Fox LeAnne , Frank Mark , Freeman Brandi , Fry Alicia , Fuller James , Galang Romeo , Gerber Sue , Gokhale Runa , Goldstein Sue , Gorman Sue , Gregg William , Greim William , Grube Steven , Hall Aron , Haynes Amber , Hill Sherrasa , Hornsby-Myers Jennifer , Hunter Jennifer , Ionta Christopher , Isenhour Cheryl , Jacobs Max , Jacobs Slifka Kara , Jernigan Daniel , Jhung Michael , Jones-Wormley Jamie , Kambhampati Anita , Kamili Shifaq , Kennedy Pamela , Kent Charlotte , Killerby Marie , Kim Lindsay , Kirking Hannah , Koonin Lisa , Koppaka Ram , Kosmos Christine , Kuhar David , Kuhnert-Tallman Wendi , Kujawski Stephanie , Kumar Archana , Landon Alexander , Lee Leslie , Leung Jessica , Lindstrom Stephen , Link-Gelles Ruth , Lively Joana , Lu Xiaoyan , Lynch Brian , Malapati Lakshmi , Mandel Samantha , Manns Brian , Marano Nina , Marlow Mariel , Marston Barbara , McClung Nancy , McClure Liz , McDonald Emily , McGovern Oliva , Messonnier Nancy , Midgley Claire , Moulia Danielle , Murray Janna , Noelte Kate , Noonan-Smith Michelle , Nordlund Kristen , Norton Emily , Oliver Sara , Pallansch Mark , Parashar Umesh , Patel Anita , Patel Manisha , Pettrone Kristen , Pierce Taran , Pietz Harald , Pillai Satish , Radonovich Lewis , Reagan-Steiner Sarah , Reel Amy , Reese Heather , Rha Brian , Ricks Philip , Rolfes Melissa , Roohi Shahrokh , Roper Lauren , Rotz Lisa , Routh Janell , Sakthivel Senthil Kumar Sarmiento Luisa , Schindelar Jessica , Schneider Eileen , Schuchat Anne , Scott Sarah , Shetty Varun , Shockey Caitlin , Shugart Jill , Stenger Mark , Stuckey Matthew , Sunshine Brittany , Sykes Tamara , Trapp Jonathan , Uyeki Timothy , Vahey Grace , Valderrama Amy , Villanueva Julie , Walker Tunicia , Wallace Megan , Wang Lijuan , Watson John , Weber Angie , Weinbaum Cindy , Weldon William , Westnedge Caroline , Whitaker Brett , Whitaker Michael , Williams Alcia , Williams Holly , Willams Ian , Wong Karen , Xie Amy , Yousef Anna . Am J Transplant 2020 20 (3) 889-895 This article summarizes what is currently known about the 2019 novel coronavirus and offers interim guidance. |
Acute hepatitis and adenovirus infection among children-Alabama, October 2021-February 2022.
Baker Julia M, Buchfellner Markus, Britt William, Sanchez Veronica, Potter Jennifer L, Ingram L Amanda, Shiau Henry, Sanchez Luz Helena Gutierrez, Saaybi Stephanie, Kelly David, Lu Xiaoyan, Vega Everardo M, Ayers-Millsap Stephanie, Willeford Wesley G, Rassaei Negar, Bullock Hannah, Reagan-Steiner Sarah, Martin Ali, Moulton Elizabeth A, Lamson Daryl M, St George Kirsten, Parashar Umesh D, Hall Aron J, MacNeil Adam, Tate Jacqueline E, Kirking Hannah L . American journal of transplantation : official journal of the American Society of Transplantation and the American Society of Transplant Surgeons 2022 7 (7) 1919-1921 |
Reduced sensitivity of SARS-CoV-2 PCR testing with single-nostril nasal swabs.
Salvatore PP , Bhattacharyya S , Christensen K , Tate JE , Kirking HL . J Clin Virol 2021 140 104852 Nasopharyngeal (NP) specimens collected by clinicians are used as the “gold standard” for diagnostic real-time reverse transcriptase polymerase chain reaction (rRT-PCR) testing for SARS-CoV-2. Previous reports indicate that two-nostril nasal swabs offer a sensitive (94%) alternative to NP specimens and are better tolerated by patients [1]. Importantly, Food and Drug Administration (FDA) authorization of nasal swab protocols require sampling of both nostrils. |
Assessment of contact tracing for COVID-19 among people experiencing homelessness, Salt Lake County Health Department, March-May 2020.
Fields VL , Kiphibane T , Eason JT , Hafoka SF , Lopez AS , Schwartz A , Henry A , Tran CH , Tate JE , Kirking HL , Laws RL , Venkatappa T , Mosites E , Montgomery MP . Ann Epidemiol 2021 59 50-55 PURPOSE: Contact tracing is intended to reduce the spread of coronavirus disease 2019 (COVID-19), but it is difficult to conduct among people who live in congregate settings, including people experiencing homelessness (PEH). This analysis compares person-based contact tracing among two populations in Salt Lake County, Utah, from March-May 2020. METHODS: All laboratory-confirmed positive cases among PEH (n=169) and documented in Utah's surveillance system were included in this analysis. The general population comparison group (n=163) were systematically selected from all laboratory-confirmed cases identified during the same period. RESULTS: Ninety-three PEH cases (55%) were interviewed compared to 163 (100%) cases among the general population (p<0.0001). PEH were more likely to be lost to follow-up at end of isolation (14.2%) versus the general population (0%; p-value<0.0001) and provided fewer contacts per case (0.31) than the general population (4.7) (p-value<0.0001). Contacts of PEH were more often unreachable (13.0% vs. 7.1%; p-value<0.0001). CONCLUSIONS: These findings suggest that contact tracing among PEH should include a location-based approach, along with a person-based approach when resources allow, due to challenges in identifying, locating, and reaching cases among PEH and their contacts through person-based contact tracing efforts alone. |
Performance of Repeat BinaxNOW SARS-CoV-2 Antigen Testing in a Community Setting, Wisconsin, November-December 2020.
Shah MM , Salvatore PP , Ford L , Kamitani E , Whaley MJ , Kaitlin M , Currie DW , Morgan CN , Segaloff HE , Lecher S , Somers T , Van Dyke ME , Bigouette JP , Delaney A , DaSilva J , O'Hegarty M , Boyle-Estheimer L , Abdirizak F , Karpathy SE , Meece J , Ivanic L , Goffard K , Gieryn D , Sterkel A , Bateman A , Kahrs J , Langolf K , Zochert T , Knight NW , Hsu CH , Kirking HL , Tate JE . Clin Infect Dis 2021 73 S54-S57 Repeating the BinaxNOW antigen test for SARS-CoV-2 by two groups of readers within 30 minutes resulted in high concordance (98.9%) in 2,110 encounters. BinaxNOW test sensitivity was 77.2% (258/334) compared to real-time reverse transcription-polymerase chain reaction. Same day antigen testing did not significantly improve test sensitivity while specificity remained high. |
Changes in Seasonal Respiratory Illnesses in the United States During the COVID-19 Pandemic.
Rodgers L , Sheppard M , Smith A , Dietz S , Jayanthi P , Yuan Y , Bull L , Wotiz S , Schwarze T , Azondekon R , Hartnett K , Adjemian J , Kirking HL , Kite Powell A . Clin Infect Dis 2021 73 S110-S117 BACKGROUND: Respiratory tract infections are common, often seasonal, and caused by multiple pathogens. We assessed whether seasonal respiratory illness patterns changed during the COVID-19 pandemic. METHODS: We categorized emergency department (ED) visits reported to the National Syndromic Surveillance Program according to chief complaints and diagnosis codes, excluding visits with diagnosed SARS-CoV-2 infections. For each week during March 1, 2020 through December 26, 2020 ("pandemic period"), we compared the proportion of ED visits in each respiratory category with the proportion of visits in that category during the corresponding weeks of 2017-2019 ("pre-pandemic period"). We analyzed positivity of respiratory viral tests from two independent clinical laboratories. RESULTS: During March 2020, cough, shortness of breath, and influenza-like illness accounted for twice as many ED visits compared with the pre-pandemic period. During the last four months of 2020, all respiratory conditions, except shortness of breath, accounted for a smaller proportion of ED visits than during the pre-pandemic period. Percent positivity for influenza virus, respiratory syncytial virus, human parainfluenza virus, adenoviruses, and human metapneumovirus were lower in 2020 than 2019. Although test volume decreased, percent positivity was higher for rhinovirus/enterovirus during the final weeks of 2020 compared with 2019; with ED visits similar to the pre-pandemic period. DISCUSSION: Broad reductions in respiratory test positivity and respiratory emergency department visits (excluding COVID-19) occurred during 2020. Interventions for mitigating spread of SARS-CoV-2 likely also reduced transmission of other pathogens. Timely surveillance is needed to understand community health threats, particularly when current trends deviate from seasonal norms. |
SARS-CoV-2 transmission in a Georgia school district - United States, December 2020-January 2021.
Gettings JR , Gold JAW , Kimball A , Forsberg K , Scott C , Uehara A , Tong S , Hast M , Swanson MR , Morris E , Oraka E , Almendares O , Thomas ES , Mehari L , McCloud J , Roberts G , Crosby D , Balajee A , Burnett E , Chancey RJ , Cook P , Donadel M , Espinosa C , Evans ME , Fleming-Dutra KE , Forero C , Kukielka EA , Li Y , Marcet PL , Mitruka K , Nakayama JY , Nakazawa Y , O'Hegarty M , Pratt C , Rice ME , Rodriguez Stewart RM , Sabogal R , Sanchez E , Velasco-Villa A , Weng MK , Zhang J , Rivera G , Parrott T , Franklin R , Memark J , Drenzek C , Hall AJ , Kirking HL , Tate JE , Vallabhaneni S . Clin Infect Dis 2021 74 (2) 319-326 BACKGROUND: To inform prevention strategies, we assessed the extent of SARS-CoV-2 transmission and settings in which transmission occurred in a Georgia public school district. METHODS: During December 1, 2020-January 22, 2021, SARS-CoV-2-infected index cases and their close contacts in schools were identified by school and public health officials. For in-school contacts, we assessed symptoms and offered SARS-CoV-2 RT-PCR testing; performed epidemiologic investigations and whole-genome sequencing to identify in-school transmission; and calculated secondary attack rate (SAR) by school setting (e.g., sports, elementary school classroom), index case role (i.e., staff, student), and index case symptomatic status. RESULTS: We identified 86 index cases and 1,119 contacts, 688 (63.1%) of whom received testing. Fifty-nine (8.7%) of 679 contacts tested positive; 15 (17.4%) of 86 index cases resulted in ≥2 positive contacts. Among 55 persons testing positive with available symptom data, 31 (56.4%) were asymptomatic. Highest SAR were in indoor, high-contact sports settings (23.8%, 95% confidence interval [CI] 12.7, 33.3), staff meetings/lunches (18.2%, CI 4.5-31.8), and elementary school classrooms (9.5%, CI 6.5-12.5). SAR was higher for staff (13.1%, CI 9.0-17.2) versus student index cases (5.8%, CI 3.6-8.0) and for symptomatic (10.9%, CI 8.1-13.9) versus asymptomatic index cases (3.0%, CI 1.0-5.5). CONCLUSIONS: Indoor sports may pose a risk to the safe operation of in-person learning. Preventing infection in staff members, through measures that include COVID-19 vaccination, is critical to reducing in-school transmission. Because many positive contacts were asymptomatic, contact tracing should be paired with testing, regardless of symptoms. |
Epidemiologic characteristics associated with SARS-CoV-2 antigen-based test results, rRT-PCR cycle threshold values, subgenomic RNA, and viral culture results from university testing.
Ford L , Lee C , Pray IW , Cole D , Bigouette JP , Abedi GR , Bushman D , Delahoy MJ , Currie DW , Cherney B , Kirby M , Fajardo G , Caudill M , Langolf K , Kahrs J , Zochert T , Kelly P , Pitts C , Lim A , Aulik N , Tamin A , Harcourt JL , Queen K , Zhang J , Whitaker B , Browne H , Medrzycki M , Shewmaker P , Bonenfant G , Zhou B , Folster J , Bankamp B , Bowen MD , Thornburg NJ , Goffard K , Limbago B , Bateman A , Tate JE , Gieryn D , Kirking HL , Westergaard R , Killerby M . Clin Infect Dis 2021 73 (6) e1348-e1355 BACKGROUND: Real-time reverse transcription polymerase chain reaction (rRT-PCR) and antigen tests are important diagnostics for SARS-CoV-2. Sensitivity of antigen tests has been shown to be lower than that of rRT-PCR; however, data to evaluate epidemiologic characteristics that affect test performance are limited. METHODS: Paired mid-turbinate nasal swabs were collected from university students and staff and tested for SARS-CoV-2 using both Quidel Sofia SARS Antigen Fluorescent Immunoassay (FIA) and rRT-PCR assay. Specimens positive by either rRT-PCR or antigen FIA were placed in viral culture and tested for subgenomic RNA (sgRNA). Logistic regression models were used to evaluate characteristics associated with antigen results, rRT-PCR cycle threshold (Ct) values, sgRNA, and viral culture. RESULTS: Antigen FIA sensitivity was 78.9% and 43.8% among symptomatic and asymptomatic participants respectively. Among rRT-PCR positive participants, negative antigen results were more likely among asymptomatic participants (OR 4.6, CI:1.3-15.4) and less likely among participants reporting nasal congestion (OR 0.1, CI:0.03-0.8). rRT-PCR-positive specimens with higher Ct values (OR 0.5, CI:0.4-0.8) were less likely, and specimens positive for sgRNA (OR 10.2, CI:1.6-65.0) more likely, to yield positive virus isolation. Antigen testing was >90% positive in specimens with Ct values <29. Positive predictive value of antigen test for positive viral culture (57.7%) was similar to that of rRT-PCR (59.3%). CONCLUSIONS: SARS-CoV-2 antigen test advantages include low cost, wide availability and rapid turnaround time, making them important screening tests. The performance of antigen tests may vary with patient characteristics, so performance characteristics should be accounted for when designing testing strategies and interpreting results. |
Factors Associated with Participation in Elementary School-Based SARS-CoV-2 Testing - Salt Lake County, Utah, December 2020-January 2021.
Lewis NM , Hershow RB , Chu VT , Wu K , Milne AT , LaCross N , Hill M , Risk I , Hersh AL , Kirking HL , Tate JE , Vallabhaneni S , Dunn AC . MMWR Morb Mortal Wkly Rep 2021 70 (15) 557-559 During December 3, 2020-January 31, 2021, CDC, in collaboration with the University of Utah Health and Economic Recovery Outreach Project,* Utah Department of Health (UDOH), Salt Lake County Health Department, and one Salt Lake county school district, offered free, in-school, real-time reverse transcription-polymerase chain reaction (RT-PCR) saliva testing as part of a transmission investigation of SARS-CoV-2, the virus that causes COVID-19, in elementary school settings. School contacts(†) of persons with laboratory-confirmed SARS-CoV-2 infection, including close contacts, were eligible to participate (1). Investigators approached parents or guardians of student contacts by telephone, and during January, using school phone lines to offer in-school specimen collection; the testing procedures were explained in the preferred language of the parent or guardian. Consent for participants was obtained via an electronic form sent by e-mail. Analyses examined participation (i.e., completing in-school specimen collection for SARS-CoV-2 testing) in relation to factors(§) that were programmatically important or could influence likelihood of SARS-CoV-2 testing, including race, ethnicity, and SARS-CoV-2 incidence in the community (2). Crude prevalence ratios (PRs) were calculated using univariate log-binomial regression.(¶) This activity was reviewed by CDC and was conducted consistent with federal law and CDC policy.*. |
Low SARS-CoV-2 Transmission in Elementary Schools - Salt Lake County, Utah, December 3, 2020-January 31, 2021.
Hershow RB , Wu K , Lewis NM , Milne AT , Currie D , Smith AR , Lloyd S , Orleans B , Young EL , Freeman B , Schwartz N , Bryant B , Espinosa C , Nakazawa Y , Garza E , Almendares O , Abara WE , Ehlman DC , Waters K , Hill M , Risk I , Oakeson K , Tate JE , Kirking HL , Dunn A , Vallabhaneni S , Hersh AL , Chu VT . MMWR Morb Mortal Wkly Rep 2021 70 (12) 442-448 School closures affected more than 55 million students across the United States when implemented as a strategy to prevent the transmission of SARS-CoV-2, the virus that causes COVID-19 (1). Reopening schools requires balancing the risks for SARS-CoV-2 infection to students and staff members against the benefits of in-person learning (2). During December 3, 2020-January 31, 2021, CDC investigated SARS-CoV-2 transmission in 20 elementary schools (kindergarten through grade 6) that had reopened in Salt Lake County, Utah. The 7-day cumulative number of new COVID-19 cases in Salt Lake County during this time ranged from 290 to 670 cases per 100,000 persons.(†) Susceptible(§) school contacts(¶) (students and staff members exposed to SARS-CoV-2 in school) of 51 index patients** (40 students and 11 staff members) were offered SARS-CoV-2 reverse transcription-polymerase chain reaction (RT-PCR) testing. Among 1,041 susceptible school contacts, 735 (70.6%) were tested, and five of 12 cases identified were classified as school-associated; the secondary attack rate among tested susceptible school contacts was 0.7%. Mask use among students was high (86%), and the median distance between students' seats in classrooms was 3 ft. Despite high community incidence and an inability to maintain ≥6 ft of distance between students at all times, SARS-CoV-2 transmission was low in these elementary schools. The results from this investigation add to the increasing evidence that in-person learning can be achieved with minimal SARS-CoV-2 transmission risk when multiple measures to prevent transmission are implemented (3,4). |
Shedding of culturable virus, seroconversion, and 6-month follow-up antibody responses in the first 14 confirmed cases of COVID-19 in the United States.
Killerby ME , Ata Ur Rasheed M , Tamin A , Harcourt JL , Abedi GR , Lu X , Kujawski S , Shah MM , Kirking HL , Gold JAW , Salvatore PP , Coughlin MM , Whitaker B , Tate JE , Watson JT , Lindstrom S , Hall AJ , Fry AM , Gerber SI , Midgley CM , Thornburg NJ . J Infect Dis 2021 224 (5) 771-776 We aimed to characterize presence of culturable virus in clinical specimens during acute illness, and antibody kinetics up to six months post-onset, among 14 early US COVID-19 patients. We isolated viable SARS-CoV-2 from rRT-PCR-positive respiratory specimens collected during days 0-8 post-onset, but not after. All 13 patients with two or more serum specimens developed anti-spike antibodies; 12 developed detectable neutralizing antibodies. We did not isolate virus after detection of neutralizing antibodies. Eight participants provided serum at six months post-onset; all retained detectable anti-spike IgG, and half had detectable neutralizing antibodies. Two participants reported not feeling fully recovered at six months. |
Persistent SARS-CoV-2 RNA Shedding without Evidence of Infectiousness: A Cohort Study of Individuals with COVID-19.
Owusu D , Pomeroy MA , Lewis NM , Wadhwa A , Yousaf AR , Whitaker B , Dietrich E , Hall AJ , Chu V , Thornburg N , Christensen K , Kiphibane T , Willardson S , Westergaard R , Dasu T , Pray IW , Bhattacharyya S , Dunn A , Tate JE , Kirking HL , Matanock A . J Infect Dis 2021 224 (8) 1362-1371 BACKGROUND: To better understand SARS-CoV-2 shedding duration and infectivity, we estimated SARS-CoV-2 RNA shedding duration, described characteristics associated with viral RNA shedding resolution1, and determined if replication-competent viruses could be recovered ≥10 days after symptom onset among individuals with mild to moderate COVID-19. METHODS: We collected serial nasopharyngeal specimens at various time points from 109 individuals with rRT-PCR-confirmed COVID-19 in Utah and Wisconsin. We calculated probability of viral RNA shedding resolution using the Kaplan-Meier estimator and evaluated characteristics associated with shedding resolution using Cox proportional hazards regression. We attempted viral culture for 35 rRT-PCR-positive nasopharyngeal specimens collected ≥10 days after symptom onset. RESULTS: The likelihood of viral RNA shedding resolution at 10 days after symptom onset was approximately 3%. Time to shedding resolution was shorter among participants aged <18 years (adjusted hazards ratio [aHR]: 3.01; 95% CI: 1.6-5.6) and longer among those aged ≥50 years (aHR: 0.50; 95% CI: 0.3-0.9) compared to participants aged 18-49 years. No replication-competent viruses were recovered. CONCLUSIONS: Although most patients were positive for SARS-CoV-2 for ≥10 days after symptom onset, our findings suggest that individuals with mild to moderate COVID-19 are unlikely to be infectious ≥10 days after symptom onset. |
Clusters of SARS-CoV-2 Infection Among Elementary School Educators and Students in One School District - Georgia, December 2020-January 2021.
Gold JAW , Gettings JR , Kimball A , Franklin R , Rivera G , Morris E , Scott C , Marcet PL , Hast M , Swanson M , McCloud J , Mehari L , Thomas ES , Kirking HL , Tate JE , Memark J , Drenzek C , Vallabhaneni S . MMWR Morb Mortal Wkly Rep 2021 70 (8) 289-292 In-person learning benefits children and communities (1). Understanding the context in which transmission of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), occurs in schools is critical to improving the safety of in-person learning. During December 1, 2020-January 22, 2021, Cobb and Douglas Public Health (CDPH), the Georgia Department of Public Health (GDPH), and CDC investigated SARS-CoV-2 transmission in eight public elementary schools in a single school district. COVID-19 cases* among educators and students were either self-reported or identified by local public health officials. Close contacts (contacts)(†) of persons with a COVID-19 case received testing. Among contacts who received positive test results, public health investigators assessed epidemiologic links, probable transmission directionality, and the likelihood of in-school transmission.(§) Nine clusters of three or more epidemiologically linked COVID-19 cases were identified involving 13 educators and 32 students at six of the eight elementary schools. Two clusters involved probable educator-to-educator transmission that was followed by educator-to-student transmission and resulted in approximately one half (15 of 31) of school-associated cases. Sixty-nine household members of persons with school-associated cases were tested, and 18 (26%) received positive results. All nine transmission clusters involved less than ideal physical distancing, and five involved inadequate mask use by students. Educators were central to in-school transmission networks. Multifaceted mitigation measures in schools, including promotion of COVID-19 precautions outside of school, minimizing in-person adult interactions at school, and ensuring universal and correct mask use and physical distancing among educators and students when in-person interaction is unavoidable, are important in preventing in-school transmission of SARS-CoV-2. Although not required for reopening schools, COVID-19 vaccination should be considered as an additional mitigation measure to be added when available. |
Characteristics and Timing of Initial Virus Shedding in Severe Acute Respiratory Syndrome Coronavirus 2, Utah, USA.
Lewis NM , Duca LM , Marcenac P , Dietrich EA , Gregory CJ , Fields VL , Banks MM , Rispens JR , Hall A , Harcourt JL , Tamin A , Willardson S , Kiphibane T , Christensen K , Dunn AC , Tate JE , Nabity S , Matanock AM , Kirking HL . Emerg Infect Dis 2021 27 (2) 352-359 Virus shedding in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can occur before onset of symptoms; less is known about symptom progression or infectiousness associated with initiation of viral shedding. We investigated household transmission in 5 households with daily specimen collection for 5 consecutive days starting a median of 4 days after symptom onset in index patients. Seven contacts across 2 households implementing no precautionary measures were infected. Of these 7, 2 tested positive for SARS-CoV-2 by reverse transcription PCR on day 3 of 5. Both had mild, nonspecific symptoms for 1-3 days preceding the first positive test. SARS-CoV-2 was cultured from the fourth-day specimen in 1 patient and from the fourth- and fifth-day specimens in the other. We also describe infection control measures taken in the households that had no transmission. Persons exposed to SARS-CoV-2 should self-isolate, including from household contacts, wear a mask, practice hand hygiene, and seek testing promptly. |
SARS-CoV-2 Transmission Dynamics in a Sleep-Away Camp.
Szablewski CM , Chang KT , McDaniel CJ , Chu VT , Yousaf AR , Schwartz NG , Brown M , Winglee K , Paul P , Cui Z , Slayton RB , Tong S , Li Y , Uehara A , Zhang J , Sharkey SM , Kirking HL , Tate JE , Dirlikov E , Fry AM , Hall AJ , Rose DA , Villanueva J , Drenzek C , Stewart RJ , Lanzieri TM . Pediatrics 2021 147 (4) OBJECTIVES: In late June 2020, a large outbreak of coronavirus disease 2019 (COVID-19) occurred at a sleep-away youth camp in Georgia, affecting primarily persons </=21 years. We conducted a retrospective cohort study among campers and staff (attendees) to determine the extent of the outbreak and assess factors contributing to transmission. METHODS: Attendees were interviewed to ascertain demographic characteristics, known exposures to COVID-19 and community exposures, and mitigation measures before, during, and after attending camp. COVID-19 case status was determined for all camp attendees on the basis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) test results and reported symptoms. We calculated attack rates and instantaneous reproduction numbers and sequenced SARS-CoV-2 viral genomes from the outbreak. RESULTS: Among 627 attendees, the median age was 15 years (interquartile range: 12-16 years); 56% (351 of 627) of attendees were female. The attack rate was 56% (351 of 627) among all attendees. On the basis of date of illness onset or first positive test result on a specimen collected, 12 case patients were infected before arriving at camp and 339 case patients were camp associated. Among 288 case patients with available symptom information, 45 (16%) were asymptomatic. Despite cohorting, 50% of attendees reported direct contact with people outside their cabin cohort. On the first day of camp session, the instantaneous reproduction number was 10. Viral genomic diversity was low. CONCLUSIONS: Few introductions of SARS-CoV-2 into a youth congregate setting resulted in a large outbreak. Testing strategies should be combined with prearrival quarantine, routine symptom monitoring with appropriate isolation and quarantine, cohorting, social distancing, mask wearing, and enhanced disinfection and hand hygiene. Promotion of mitigation measures among younger populations is needed. |
Evaluation of Abbott BinaxNOW Rapid Antigen Test for SARS-CoV-2 Infection at Two Community-Based Testing Sites - Pima County, Arizona, November 3-17, 2020.
Prince-Guerra JL , Almendares O , Nolen LD , Gunn JKL , Dale AP , Buono SA , Deutsch-Feldman M , Suppiah S , Hao L , Zeng Y , Stevens VA , Knipe K , Pompey J , Atherstone C , Bui DP , Powell T , Tamin A , Harcourt JL , Shewmaker PL , Medrzycki M , Wong P , Jain S , Tejada-Strop A , Rogers S , Emery B , Wang H , Petway M , Bohannon C , Folster JM , MacNeil A , Salerno R , Kuhnert-Tallman W , Tate JE , Thornburg NJ , Kirking HL , Sheiban K , Kudrna J , Cullen T , Komatsu KK , Villanueva JM , Rose DA , Neatherlin JC , Anderson M , Rota PA , Honein MA , Bower WA . MMWR Morb Mortal Wkly Rep 2021 70 (3) 100-105 Rapid antigen tests, such as the Abbott BinaxNOW COVID-19 Ag Card (BinaxNOW), offer results more rapidly (approximately 15-30 minutes) and at a lower cost than do highly sensitive nucleic acid amplification tests (NAATs) (1). Rapid antigen tests have received Food and Drug Administration (FDA) Emergency Use Authorization (EUA) for use in symptomatic persons (2), but data are lacking on test performance in asymptomatic persons to inform expanded screening testing to rapidly identify and isolate infected persons (3). To evaluate the performance of the BinaxNOW rapid antigen test, it was used along with real-time reverse transcription-polymerase chain reaction (RT-PCR) testing to analyze 3,419 paired specimens collected from persons aged ≥10 years at two community testing sites in Pima County, Arizona, during November 3-17, 2020. Viral culture was performed on 274 of 303 residual real-time RT-PCR specimens with positive results by either test (29 were not available for culture). Compared with real-time RT-PCR testing, the BinaxNOW antigen test had a sensitivity of 64.2% for specimens from symptomatic persons and 35.8% for specimens from asymptomatic persons, with near 100% specificity in specimens from both groups. Virus was cultured from 96 of 274 (35.0%) specimens, including 85 (57.8%) of 147 with concordant antigen and real-time RT-PCR positive results, 11 (8.9%) of 124 with false-negative antigen test results, and none of three with false-positive antigen test results. Among specimens positive for viral culture, sensitivity was 92.6% for symptomatic and 78.6% for asymptomatic individuals. When the pretest probability for receiving positive test results for SARS-CoV-2 is elevated (e.g., in symptomatic persons or in persons with a known COVID-19 exposure), a negative antigen test result should be confirmed by NAAT (1). Despite a lower sensitivity to detect infection, rapid antigen tests can be an important tool for screening because of their quick turnaround time, lower costs and resource needs, high specificity, and high positive predictive value (PPV) in settings of high pretest probability. The faster turnaround time of the antigen test can help limit transmission by more rapidly identifying infectious persons for isolation, particularly when used as a component of serial testing strategies. |
Performance of an Antigen-Based Test for Asymptomatic and Symptomatic SARS-CoV-2 Testing at Two University Campuses - Wisconsin, September-October 2020.
Pray IW , Ford L , Cole D , Lee C , Bigouette JP , Abedi GR , Bushman D , Delahoy MJ , Currie D , Cherney B , Kirby M , Fajardo G , Caudill M , Langolf K , Kahrs J , Kelly P , Pitts C , Lim A , Aulik N , Tamin A , Harcourt JL , Queen K , Zhang J , Whitaker B , Browne H , Medrzycki M , Shewmaker P , Folster J , Bankamp B , Bowen MD , Thornburg NJ , Goffard K , Limbago B , Bateman A , Tate JE , Gieryn D , Kirking HL , Westergaard R , Killerby M . MMWR Morb Mortal Wkly Rep 2021 69 (5152) 1642-1647 Antigen-based tests for SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), are inexpensive and can return results within 15 minutes (1). Antigen tests have received Food and Drug Administration (FDA) Emergency Use Authorization (EUA) for use in asymptomatic and symptomatic persons within the first 5-12 days after symptom onset (2). These tests have been used at U.S. colleges and universities and other congregate settings (e.g., nursing homes and correctional and detention facilities), where serial testing of asymptomatic persons might facilitate early case identification (3-5). However, test performance data from symptomatic and asymptomatic persons are limited. This investigation evaluated performance of the Sofia SARS Antigen Fluorescent Immunoassay (FIA) (Quidel Corporation) compared with real-time reverse transcription-polymerase chain reaction (RT-PCR) for SARS-CoV-2 detection among asymptomatic and symptomatic persons at two universities in Wisconsin. During September 28-October 9, a total of 1,098 paired nasal swabs were tested using the Sofia SARS Antigen FIA and real-time RT-PCR. Virus culture was attempted on all antigen-positive or real-time RT-PCR-positive specimens. Among 871 (79%) paired swabs from asymptomatic participants, the antigen test sensitivity was 41.2%, specificity was 98.4%, and in this population the estimated positive predictive value (PPV) was 33.3%, and negative predictive value (NPV) was 98.8%. Antigen test performance was improved among 227 (21%) paired swabs from participants who reported one or more symptoms at specimen collection (sensitivity = 80.0%; specificity = 98.9%; PPV = 94.1%; NPV = 95.9%). Virus was isolated from 34 (46.6%) of 73 antigen-positive or real-time RT-PCR-positive nasal swab specimens, including two of 18 that were antigen-negative and real-time RT-PCR-positive (false-negatives). The advantages of antigen tests such as low cost and rapid turnaround might allow for rapid identification of infectious persons. However, these advantages need to be balanced against lower sensitivity and lower PPV, especially among asymptomatic persons. Confirmatory testing with an FDA-authorized nucleic acid amplification test (NAAT), such as RT-PCR, should be considered after negative antigen test results in symptomatic persons, and after positive antigen test results in asymptomatic persons (1). |
Household Transmission of SARS-CoV-2 in the United States.
Lewis NM , Chu VT , Ye D , Conners EE , Gharpure R , Laws RL , Reses HE , Freeman BD , Fajans M , Rabold EM , Dawson P , Buono S , Yin S , Owusu D , Wadhwa A , Pomeroy M , Yousaf A , Pevzner E , Njuguna H , Battey KA , Tran CH , Fields VL , Salvatore P , O'Hegarty M , Vuong J , Chancey R , Gregory C , Banks M , Rispens JR , Dietrich E , Marcenac P , Matanock AM , Duca L , Binder A , Fox G , Lester S , Mills L , Gerber SI , Watson J , Schumacher A , Pawloski L , Thornburg NJ , Hall AJ , Kiphibane T , Willardson S , Christensen K , Page L , Bhattacharyya S , Dasu T , Christiansen A , Pray IW , Westergaard RP , Dunn AC , Tate JE , Nabity SA , Kirking HL . Clin Infect Dis 2020 73 (7) 1805-1813 BACKGROUND: Although many viral respiratory illnesses are transmitted within households, the evidence base for SARS-CoV-2 is nascent. We sought to characterize SARS-CoV-2 transmission within US households and estimate the household secondary infection rate (SIR) to inform strategies to reduce transmission. METHODS: We recruited laboratory-confirmed COVID-19 patients and their household contacts in Utah and Wisconsin during March 22-April 25, 2020. We interviewed patients and all household contacts to obtain demographics and medical histories. At the initial household visit, 14 days later, and when a household contact became newly symptomatic, we collected respiratory swabs from patients and household contacts for testing by SARS-CoV-2 rRT-PCR and sera for SARS-CoV-2 antibodies testing by enzyme-linked immunosorbent assay (ELISA). We estimated SIR and odds ratios (OR) to assess risk factors for secondary infection, defined by a positive rRT-PCR or ELISA test. RESULTS: Thirty-two (55%) of 58 households had evidence of secondary infection among household contacts. The SIR was 29% (n = 55/188; 95% confidence interval [CI]: 23-36%) overall, 42% among children (<18 years) of the COVID-19 patient and 33% among spouses/partners. Household contacts to COVID-19 patients with immunocompromised conditions had increased odds of infection (OR: 15.9, 95% CI: 2.4-106.9). Household contacts who themselves had diabetes mellitus had increased odds of infection (OR: 7.1, 95% CI: 1.2-42.5). CONCLUSIONS: We found substantial evidence of secondary infections among household contacts. People with COVID-19, particularly those with immunocompromising conditions or those with household contacts with diabetes, should take care to promptly self-isolate to prevent household transmission. |
Lack of Serologic Evidence of Infection Among Health Care Personnel and Other Contacts of First 2 Confirmed Patients With COVID-19 in Illinois, 2020.
McPherson TD , Ghinai I , Binder AM , Freeman BD , Hoskin Snelling C , Hunter JC , Anderson KM , Davenport P , Rudd DL , Zafer M , Christiansen D , Joshi K , Rubin R , Black SR , Fricchione MJ , Pacilli M , Walblay KA , Korpics J , Moeller D , Quartey-Kumapley P , Wang C , Charles EM , Kauerauf J , Patel MT , Disari VS , Fischer M , Jacobs MW , Lester SN , Midgley CM , Rasheed MAU , Reese HE , Verani JR , Wallace M , Watson JT , Thornburg NJ , Layden JE , Kirking HL . Public Health Rep 2020 136 (1) 88-96 OBJECTIVES: Widespread global transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus causing coronavirus disease 2019 (COVID-19), continues. Many questions remain about asymptomatic or atypical infections and transmission dynamics. We used comprehensive contact tracing of the first 2 confirmed patients in Illinois with COVID-19 and serologic SARS-CoV-2 antibody testing to determine whether contacts had evidence of undetected COVID-19. METHODS: Contacts were eligible for serologic follow-up if previously tested for COVID-19 during an initial investigation or had greater-risk exposures. Contacts completed a standardized questionnaire during the initial investigation. We classified exposure risk as high, medium, or low based on interactions with 2 index patients and use of personal protective equipment (PPE). Serologic testing used a SARS-CoV-2 spike enzyme-linked immunosorbent assay on serum specimens collected from participants approximately 6 weeks after initial exposure to either index patient. The 2 index patients provided serum specimens throughout their illness. We collected data on demographic, exposure, and epidemiologic characteristics. RESULTS: Of 347 contacts, 110 were eligible for serologic follow-up; 59 (17% of all contacts) enrolled. Of these, 53 (90%) were health care personnel and 6 (10%) were community contacts. Seventeen (29%) reported high-risk exposures, 15 (25%) medium-risk, and 27 (46%) low-risk. No participant had evidence of SARS-CoV-2 antibodies. The 2 index patients had antibodies detected at dilutions >1:6400 within 4 weeks after symptom onset. CONCLUSIONS: In serologic follow-up of the first 2 known patients in Illinois with COVID-19, we found no secondary transmission among tested contacts. Lack of seroconversion among these contacts adds to our understanding of conditions (ie, use of PPE) under which SARS-CoV-2 infections might not result in transmission and demonstrates that SARS-CoV-2 antibody testing is a useful tool to verify epidemiologic findings. |
Symptoms and Transmission of SARS-CoV-2 Among Children - Utah and Wisconsin, March-May 2020.
Laws RL , Chancey RJ , Rabold EM , Chu VT , Lewis NM , Fajans M , Reses HE , Duca LM , Dawson P , Conners EE , Gharpure R , Yin S , Buono S , Pomeroy M , Yousaf AR , Owusu D , Wadhwa A , Pevzner E , Battey KA , Njuguna H , Fields VL , Salvatore P , O'Hegarty M , Vuong J , Gregory CJ , Banks M , Rispens J , Dietrich E , Marcenac P , Matanock A , Pray I , Westergaard R , Dasu T , Bhattacharyya S , Christiansen A , Page L , Dunn A , Atkinson-Dunn R , Christensen K , Kiphibane T , Willardson S , Fox G , Ye D , Nabity SA , Binder A , Freeman BD , Lester S , Mills L , Thornburg N , Hall AJ , Fry AM , Tate JE , Tran CH , Kirking HL . Pediatrics 2020 147 (1) BACKGROUND AND OBJECTIVES: Limited data exist on severe acute respiratory syndrome coronavirus 2 in children. We described infection rates and symptom profiles among pediatric household contacts of individuals with coronavirus disease 2019. METHODS: We enrolled individuals with coronavirus disease 2019 and their household contacts, assessed daily symptoms prospectively for 14 days, and obtained specimens for severe acute respiratory syndrome coronavirus 2 real-time reverse transcription polymerase chain reaction and serology testing. Among pediatric contacts (<18 years), we described transmission, assessed the risk factors for infection, and calculated symptom positive and negative predictive values. We compared secondary infection rates and symptoms between pediatric and adult contacts using generalized estimating equations. RESULTS: Among 58 households, 188 contacts were enrolled (120 adults; 68 children). Secondary infection rates for adults (30%) and children (28%) were similar. Among households with potential for transmission from children, child-to-adult transmission may have occurred in 2 of 10 (20%), and child-to-child transmission may have occurred in 1 of 6 (17%). Pediatric case patients most commonly reported headache (79%), sore throat (68%), and rhinorrhea (68%); symptoms had low positive predictive values, except measured fever (100%; 95% confidence interval [CI]: 44% to 100%). Compared with symptomatic adults, children were less likely to report cough (odds ratio [OR]: 0.15; 95% CI: 0.04 to 0.57), loss of taste (OR: 0.21; 95% CI: 0.06 to 0.74), and loss of smell (OR: 0.29; 95% CI: 0.09 to 0.96) and more likely to report sore throat (OR: 3.4; 95% CI: 1.04 to 11.18). CONCLUSIONS: Children and adults had similar secondary infection rates, but children generally had less frequent and severe symptoms. In two states early in the pandemic, we observed possible transmission from children in approximately one-fifth of households with potential to observe such transmission patterns. |
Mitigating a COVID-19 Outbreak Among Major League Baseball Players - United States, 2020.
Murray MT , Riggs MA , Engelthaler DM , Johnson C , Watkins S , Longenberger A , Brett-Major DM , Lowe J , Broadhurst MJ , Ladva CN , Villanueva JM , MacNeil A , Qari S , Kirking HL , Cherry M , Khan AS . MMWR Morb Mortal Wkly Rep 2020 69 (42) 1542-1546 Mass gatherings have been implicated in higher rates of transmission of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), and many sporting events have been restricted or canceled to limit disease spread (1). Based on current CDC COVID-19 mitigation recommendations related to events and gatherings (2), Major League Baseball (MLB) developed new health and safety protocols before the July 24 start of the 2020 season. In addition, MLB made the decision that games would be played without spectators. Before a three-game series between teams A and B, the Philadelphia Department of Public Health was notified of a team A player with laboratory-confirmed COVID-19; the player was isolated as recommended (2). During the series and the week after, laboratory-confirmed COVID-19 was diagnosed among 19 additional team A players and staff members and one team B staff member. Throughout their potentially infectious periods, some asymptomatic team A players and coaches, who subsequently received positive SARS-CoV-2 test results, engaged in on-field play with teams B and C. No on-field team B or team C players or staff members subsequently received a clinical diagnosis of COVID-19. Certain MLB health and safety protocols, which include frequent diagnostic testing for rapid case identification, isolation of persons with positive test results, quarantine for close contacts, mask wearing, and social distancing, might have limited COVID-19 transmission between teams. |
Epidemiological Correlates of PCR Cycle Threshold Values in the Detection of SARS-CoV-2.
Salvatore PP , Dawson P , Wadhwa A , Rabold EM , Buono S , Dietrich EA , Reses HE , Vuong J , Pawloski L , Dasu T , Bhattacharyya S , Pevzner E , Hall AJ , Tate JE , Kirking HL . Clin Infect Dis 2020 72 (11) e761-e767 BACKGROUND: Detection of SARS-CoV-2 infection has principally been performed through the use of real-time reverse-transcription PCR (rRT-PCR) testing. Results of such tests can be reported as cycle threshold (Ct) values, which may provide semi-quantitative or indirect measurements of viral load. Previous reports have examined temporal trends in Ct values over the course of a SARS-CoV-2 infection. METHODS: Using testing data collected during a prospective household transmission investigation of outpatient and mild COVID-19 cases, we examined the relationship between Ct values of the viral RNA N1 target and demographic, clinical, and epidemiological characteristics collected through participant interviews and daily symptom diaries. RESULTS: We found Ct values are lowest (corresponding to higher viral RNA concentration) soon after symptom onset and are significantly correlated with time elapsed since onset (p<0.001); within 7 days after symptom onset, the median Ct value was 26.5 compared with a median Ct value of 35.0 occurring 21 days after onset. Ct values were significantly lower among participants under 18 years of age (p=0.01) and those reporting upper respiratory symptoms at the time of sample collection (p=0.001) and were higher among participants reporting no symptoms (p=0.05). CONCLUSIONS: These results emphasize the importance of early testing for SARS-CoV-2 among individuals with symptoms of respiratory illness and allows cases to be identified and isolated when their viral shedding may be highest. |
Adolescent with COVID-19 as the Source of an Outbreak at a 3-Week Family Gathering - Four States, June-July 2020.
Schwartz NG , Moorman AC , Makaretz A , Chang KT , Chu VT , Szablewski CM , Yousaf AR , Brown MM , Clyne A , DellaGrotta A , Drobeniuc J , Korpics J , Muir A , Drenzek C , Bandy U , Kirking HL , Tate JE , Hall AJ , Lanzieri TM , Stewart RJ . MMWR Morb Mortal Wkly Rep 2020 69 (40) 1457-1459 There is increasing evidence that children and adolescents can efficiently transmit SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19) (1-3). During July-August 2020, four state health departments and CDC investigated a COVID-19 outbreak that occurred during a 3-week family gathering of five households in which an adolescent aged 13 years was the index and suspected primary patient; 11 subsequent cases occurred. |
Transmission Dynamics of COVID-19 Outbreaks Associated with Child Care Facilities - Salt Lake City, Utah, April-July 2020.
Lopez AS , Hill M , Antezano J , Vilven D , Rutner T , Bogdanow L , Claflin C , Kracalik IT , Fields VL , Dunn A , Tate JE , Kirking HL , Kiphibane T , Risk I , Tran CH . MMWR Morb Mortal Wkly Rep 2020 69 (37) 1319-1323 Reports suggest that children aged ≥10 years can efficiently transmit SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19) (1,2). However, limited data are available on SARS-CoV-2 transmission from young children, particularly in child care settings (3). To better understand transmission from young children, contact tracing data collected from three COVID-19 outbreaks in child care facilities in Salt Lake County, Utah, during April 1-July 10, 2020, were retrospectively reviewed to explore attack rates and transmission patterns. A total of 184 persons, including 110 (60%) children had a known epidemiologic link to one of these three facilities. Among these persons, 31 confirmed COVID-19 cases occurred; 13 (42%) in children. Among pediatric patients with facility-associated confirmed COVID-19, all had mild or no symptoms. Twelve children acquired COVID-19 in child care facilities. Transmission was documented from these children to at least 12 (26%) of 46 nonfacility contacts (confirmed or probable cases). One parent was hospitalized. Transmission was observed from two of three children with confirmed, asymptomatic COVID-19. Detailed contact tracing data show that children can play a role in transmission from child care settings to household contacts. Having SARS-CoV-2 testing available, timely results, and testing of contacts of persons with COVID-19 in child care settings regardless of symptoms can help prevent transmission. CDC guidance for child care programs recommends the use of face masks, particularly among staff members, especially when children are too young to wear masks, along with hand hygiene, frequent cleaning and disinfecting of high-touch surfaces, and staying home when ill to reduce SARS-CoV-2 transmission (4). |
Enhanced contact investigations for nine early travel-related cases of SARS-CoV-2 in the United States.
Burke RM , Balter S , Barnes E , Barry V , Bartlett K , Beer KD , Benowitz I , Biggs HM , Bruce H , Bryant-Genevier J , Cates J , Chatham-Stephens K , Chea N , Chiou H , Christiansen D , Chu VT , Clark S , Cody SH , Cohen M , Conners EE , Dasari V , Dawson P , DeSalvo T , Donahue M , Dratch A , Duca L , Duchin J , Dyal JW , Feldstein LR , Fenstersheib M , Fischer M , Fisher R , Foo C , Freeman-Ponder B , Fry AM , Gant J , Gautom R , Ghinai I , Gounder P , Grigg CT , Gunzenhauser J , Hall AJ , Han GS , Haupt T , Holshue M , Hunter J , Ibrahim MB , Jacobs MW , Jarashow MC , Joshi K , Kamali T , Kawakami V , Kim M , Kirking HL , Kita-Yarbro A , Klos R , Kobayashi M , Kocharian A , Lang M , Layden J , Leidman E , Lindquist S , Lindstrom S , Link-Gelles R , Marlow M , Mattison CP , McClung N , McPherson TD , Mello L , Midgley CM , Novosad S , Patel MT , Pettrone K , Pillai SK , Pray IW , Reese HE , Rhodes H , Robinson S , Rolfes M , Routh J , Rubin R , Rudman SL , Russell D , Scott S , Shetty V , Smith-Jeffcoat SE , Soda EA , Spitters C , Stierman B , Sunenshine R , Terashita D , Traub E , Vahey GM , Verani JR , Wallace M , Westercamp M , Wortham J , Xie A , Yousaf A , Zahn M . PLoS One 2020 15 (9) e0238342 Coronavirus disease 2019 (COVID-19), the respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was first identified in Wuhan, China and has since become pandemic. In response to the first cases identified in the United States, close contacts of confirmed COVID-19 cases were investigated to enable early identification and isolation of additional cases and to learn more about risk factors for transmission. Close contacts of nine early travel-related cases in the United States were identified and monitored daily for development of symptoms (active monitoring). Selected close contacts (including those with exposures categorized as higher risk) were targeted for collection of additional exposure information and respiratory samples. Respiratory samples were tested for SARS-CoV-2 by real-time reverse transcription polymerase chain reaction at the Centers for Disease Control and Prevention. Four hundred four close contacts were actively monitored in the jurisdictions that managed the travel-related cases. Three hundred thirty-eight of the 404 close contacts provided at least basic exposure information, of whom 159 close contacts had ≥1 set of respiratory samples collected and tested. Across all actively monitored close contacts, two additional symptomatic COVID-19 cases (i.e., secondary cases) were identified; both secondary cases were in spouses of travel-associated case patients. When considering only household members, all of whom had ≥1 respiratory sample tested for SARS-CoV-2, the secondary attack rate (i.e., the number of secondary cases as a proportion of total close contacts) was 13% (95% CI: 4-38%). The results from these contact tracing investigations suggest that household members, especially significant others, of COVID-19 cases are at highest risk of becoming infected. The importance of personal protective equipment for healthcare workers is also underlined. Isolation of persons with COVID-19, in combination with quarantine of exposed close contacts and practice of everyday preventive behaviors, is important to mitigate spread of COVID-19. |
A prospective cohort study in non-hospitalized household contacts with SARS-CoV-2 infection: symptom profiles and symptom change over time.
Yousaf AR , Duca LM , Chu V , Reses HE , Fajans M , Rabold EM , Laws RL , Gharpure R , Matanock A , Wadhwa A , Pomeroy M , Njuguna H , Fox G , Binder AM , Christiansen A , Freeman B , Gregory C , Tran CH , Owusu D , Ye D , Dietrich E , Pevzner E , Conners EE , Pray I , Rispens J , Vuong J , Christensen K , Banks M , O'Hegarty M , Mills L , Lester S , Thornburg NJ , Lewis N , Dawson P , Marcenac P , Salvatore P , Chancey RJ , Fields V , Buono S , Yin S , Gerber S , Kiphibane T , Dasu T , Bhattacharyya S , Westergaard R , Dunn A , Hall AJ , Fry AM , Tate JE , Kirking HL , Nabity S . Clin Infect Dis 2020 73 (7) e1841-e1849 BACKGROUND: Improved understanding of SARS-CoV-2 spectrum of disease is essential for clinical and public health interventions. There are limited data on mild or asymptomatic infections, but recognition of these individuals is key as they contribute to viral transmission. We describe the symptom profiles from individuals with mild or asymptomatic SARS-CoV-2 infection. METHODS: From March 22 to April 22, 2020 in Wisconsin and Utah, we enrolled and prospectively observed 198 household contacts exposed to SARS-CoV-2. We collected and tested nasopharyngeal (NP) specimens by RT-PCR two or more times during a 14-day period. Contacts completed daily symptom diaries. We characterized symptom profiles on the date of first positive RT-PCR test and described progression of symptoms over time. RESULTS: We identified 47 contacts, median age 24 (3-75) years, with detectable SARS-CoV-2 by RT-PCR. The most commonly reported symptoms on the day of first positive RT-PCR test were upper respiratory (n=32, 68%) and neurologic (n=30, 64%); fever was not commonly reported (n=9, 19%). Eight (17%) individuals were asymptomatic at the date of first positive RT-PCR collection; two (4%) had preceding symptoms that resolved and six (13%) subsequently developed symptoms. Children less frequently reported lower respiratory symptoms (age <18: 21%, age 18-49: 60%, age 50+ years: 69%; p=0.03). CONCLUSIONS: Household contacts with lab-confirmed SARS-CoV-2 infection reported mild symptoms. When assessed at a single time-point, several contacts appeared to have asymptomatic infection; however, over time all developed symptoms. These findings are important to inform infection control, contact tracing, and community mitigation strategies. |
SARS-CoV-2 Transmission and Infection Among Attendees of an Overnight Camp - Georgia, June 2020.
Szablewski CM , Chang KT , Brown MM , Chu VT , Yousaf AR , Anyalechi N , Aryee PA , Kirking HL , Lumsden M , Mayweather E , McDaniel CJ , Montierth R , Mohammed A , Schwartz NG , Shah JA , Tate JE , Dirlikov E , Drenzek C , Lanzieri TM , Stewart RJ . MMWR Morb Mortal Wkly Rep 2020 69 (31) 1023-1025 Limited data are available about transmission of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), among youths. During June 17-20, an overnight camp in Georgia (camp A) held orientation for 138 trainees and 120 staff members; staff members remained for the first camp session, scheduled during June 21-27, and were joined by 363 campers and three senior staff members on June 21. Camp A adhered to the measures in Georgia's Executive Order* that allowed overnight camps to operate beginning on May 31, including requiring all trainees, staff members, and campers to provide documentation of a negative viral SARS-CoV-2 test ≤12 days before arriving. Camp A adopted most(†) components of CDC's Suggestions for Youth and Summer Camps(§) to minimize the risk for SARS-CoV-2 introduction and transmission. Measures not implemented were cloth masks for campers and opening windows and doors for increased ventilation in buildings. Cloth masks were required for staff members. Camp attendees were cohorted by cabin and engaged in a variety of indoor and outdoor activities, including daily vigorous singing and cheering. On June 23, a teenage staff member left camp A after developing chills the previous evening. The staff member was tested and reported a positive test result for SARS-CoV-2 the following day (June 24). Camp A officials began sending campers home on June 24 and closed the camp on June 27. On June 25, the Georgia Department of Public Health (DPH) was notified and initiated an investigation. DPH recommended that all attendees be tested and self-quarantine, and isolate if they had a positive test result. |
Loss of Taste and Smell as Distinguishing Symptoms of Coronavirus Disease 2019.
Dawson P , Rabold EM , Laws RL , Conners EE , Gharpure R , Yin S , Buono SA , Dasu T , Bhattacharyya S , Westergaard RP , Pray IW , Ye D , Nabity SA , Tate JE , Kirking HL . Clin Infect Dis 2020 72 (4) 682-685 In a household study, loss of taste and/or smell was the fourth most reported symptom (26/42; 62%) among COVID-19 case-patients and had the highest positive predictive value (83%; 95% CI: 55-95%) among household contacts. Olfactory and taste dysfunctions should be considered for COVID-19 case identification and testing prioritization. |
High COVID-19 Attack Rate Among Attendees at Events at a Church - Arkansas, March 2020.
James A , Eagle L , Phillips C , Hedges DS , Bodenhamer C , Brown R , Wheeler JG , Kirking H . MMWR Morb Mortal Wkly Rep 2020 69 (20) 632-635 On March 16, 2020, the day that national social distancing guidelines were released (1), the Arkansas Department of Health (ADH) was notified of two cases of coronavirus disease 2019 (COVID-19) from a rural county of approximately 25,000 persons; these cases were the first identified in this county. The two cases occurred in a husband and wife; the husband is the pastor at a local church (church A). The couple (the index cases) attended church-related events during March 6-8, and developed nonspecific respiratory symptoms and fever on March 10 (wife) and 11 (husband). Before his symptoms had developed, the husband attended a Bible study group on March 11. Including the index cases, 35 confirmed COVID-19 cases occurred among 92 (38%) persons who attended events held at church A during March 6-11; three patients died. The age-specific attack rates among persons aged </=18 years, 19-64 years, and >/=65 years were 6.3%, 59.4%, and 50.0%, respectively. During contact tracing, at least 26 additional persons with confirmed COVID-19 cases were identified among community members who reported contact with church A attendees and likely were infected by them; one of the additional persons was hospitalized and subsequently died. This outbreak highlights the potential for widespread transmission of SARS-CoV-2, the virus that causes COVID-19, both at group gatherings during church events and within the broader community. These findings underscore the opportunity for faith-based organizations to prevent COVID-19 by following local authorities' guidance and the U.S. Government's Guidelines: Opening Up America Again (2) regarding modification of activities to prevent virus transmission during the COVID-19 pandemic. |
Community Transmission of SARS-CoV-2 at Two Family Gatherings - Chicago, Illinois, February-March 2020.
Ghinai I , Woods S , Ritger KA , McPherson TD , Black SR , Sparrow L , Fricchione MJ , Kerins JL , Pacilli M , Ruestow PS , Arwady MA , Beavers SF , Payne DC , Kirking HL , Layden JE . MMWR Morb Mortal Wkly Rep 2020 69 (15) 446-450 SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), has spread rapidly around the world since it was first recognized in late 2019. Most early reports of person-to-person SARS-CoV-2 transmission have been among household contacts, where the secondary attack rate has been estimated to exceed 10% (1), in health care facilities (2), and in congregate settings (3). However, widespread community transmission, as is currently being observed in the United States, requires more expansive transmission events between nonhousehold contacts. In February and March 2020, the Chicago Department of Public Health (CDPH) investigated a large, multifamily cluster of COVID-19. Patients with confirmed COVID-19 and their close contacts were interviewed to better understand nonhousehold, community transmission of SARS-CoV-2. This report describes the cluster of 16 cases of confirmed or probable COVID-19, including three deaths, likely resulting from transmission of SARS-CoV-2 at two family gatherings (a funeral and a birthday party). These data support current CDC social distancing recommendations intended to reduce SARS-CoV-2 transmission. U.S residents should follow stay-at-home orders when required by state or local authorities. |
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