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1.
Infect Control Hosp Epidemiol ; : 1-24, 2021 Nov 22.
Article in English | MEDLINE | ID: covidwho-1527934

ABSTRACT

OBJECTIVE: Characterize and compare SARS-CoV-2-specific immune responses in plasma and gingival crevicular fluid (GCF) from nursing home residents during and after natural infection. DESIGN: Prospective cohort. SETTING: Nursing home. PARTICIPANTS: SARS-CoV-2-infected nursing home residents. METHODS: A convenience sample of 14 SARS-CoV-2-infected nursing home residents, enrolled 4-13 days after real-time reverse transcription polymerase chain reaction diagnosis, were followed for 42 days. Post diagnosis, plasma SARS-CoV-2-specific pan-Immunoglobulin (Ig), IgG, IgA, IgM, and neutralizing antibodies were measured at 5 timepoints and GCF SARS-CoV-2-specific IgG and IgA were measured at 4 timepoints. RESULTS: All participants demonstrated immune responses to SARS-CoV-2 infection. Among 12 phlebotomized participants, plasma was positive for pan-Ig and IgG in all 12, neutralizing antibodies in 11, IgM in 10, and IgA in 9. Among 14 participants with GCF specimens, GCF was positive for IgG in 13 and IgA in 12. Immunoglobulin responses in plasma and GCF had similar kinetics; median times to peak antibody response was similar across specimen types (4 weeks for IgG; 3 weeks for IgA). Participants with pan-Ig, IgG, and IgA detected in plasma and GCF IgG remained positive through this evaluation's end 46-55 days post-diagnosis. All participants were viral culture negative by the first detection of antibodies. CONCLUSIONS: Nursing home residents had detectable SARS-CoV-2 antibodies in plasma and GCF after infection. Kinetics of antibodies detected in GCF mirrored those from plasma. Non-invasive GCF may be useful for detecting and monitoring immunologic responses in populations unable or unwilling to be phlebotomized.

2.
Ann Intern Med ; 174(7): 945-951, 2021 07.
Article in English | MEDLINE | ID: covidwho-1318465

ABSTRACT

BACKGROUND: To address high COVID-19 burden in U.S. nursing homes, rapid SARS-CoV-2 antigen tests have been widely distributed in those facilities. However, performance data are lacking, especially in asymptomatic people. OBJECTIVE: To evaluate the performance of SARS-CoV-2 antigen testing when used for facility-wide testing during a nursing home outbreak. DESIGN: A prospective evaluation involving 3 facility-wide rounds of testing where paired respiratory specimens were collected to evaluate the performance of the BinaxNOW antigen test compared with virus culture and real-time reverse transcription polymerase chain reaction (RT-PCR). Early and late infection were defined using changes in RT-PCR cycle threshold values and prior test results. SETTING: A nursing home with an ongoing SARS-CoV-2 outbreak. PARTICIPANTS: 532 paired specimens collected from 234 available residents and staff. MEASUREMENTS: Percentage of positive agreement (PPA) and percentage of negative agreement (PNA) for BinaxNOW compared with RT-PCR and virus culture. RESULTS: BinaxNOW PPA with virus culture, used for detection of replication-competent virus, was 95%. However, the overall PPA of antigen testing with RT-PCR was 69%, and PNA was 98%. When only the first positive test result was analyzed for each participant, PPA of antigen testing with RT-PCR was 82% among 45 symptomatic people and 52% among 343 asymptomatic people. Compared with RT-PCR and virus culture, the BinaxNOW test performed well in early infection (86% and 95%, respectively) and poorly in late infection (51% and no recovered virus, respectively). LIMITATION: Accurate symptom ascertainment was challenging in nursing home residents; test performance may not be representative of testing done by nonlaboratory staff. CONCLUSION: Despite lower positive agreement compared with RT-PCR, antigen test positivity had higher agreement with shedding of replication-competent virus. These results suggest that antigen testing could be a useful tool to rapidly identify contagious people at risk for transmitting SARS-CoV-2 during nascent outbreaks and help reduce COVID-19 burden in nursing homes. PRIMARY FUNDING SOURCE: None.


Subject(s)
Antigens, Viral/analysis , COVID-19 Serological Testing/methods , COVID-19/diagnosis , Nursing Homes , Pandemics , SARS-CoV-2/immunology , COVID-19/epidemiology , False Negative Reactions , False Positive Reactions , Humans , Prospective Studies , Retrospective Studies , United States/epidemiology
3.
Clin Infect Dis ; 73(Suppl 1): S58-S64, 2021 07 15.
Article in English | MEDLINE | ID: covidwho-1315676

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing remains essential for early identification and clinical management of cases. We compared the diagnostic performance of 3 specimen types for characterizing SARS-CoV-2 in infected nursing home residents. METHODS: A convenience sample of 17 residents were enrolled within 15 days of first positive SARS-CoV-2 result by real-time reverse transcription polymerase chain reaction (RT-PCR) and prospectively followed for 42 days. Anterior nasal swabs (AN), oropharyngeal swabs (OP), and saliva specimens (SA) were collected on the day of enrollment, every 3 days for the first 21 days, and then weekly for 21 days. Specimens were tested for presence of SARS-CoV-2 RNA using RT-PCR and replication-competent virus by viral culture. RESULTS: Comparing the 3 specimen types collected from each participant at each time point, the concordance of paired RT-PCR results ranged from 80% to 88%. After the first positive result, SA and OP were RT-PCR-positive for ≤48 days; AN were RT-PCR-positive for ≤33 days. AN had the highest percentage of RT-PCR-positive results (21/26 [81%]) when collected ≤10 days of participants' first positive result. Eleven specimens were positive by viral culture: 9 AN collected ≤19 days following first positive result and 2 OP collected ≤5 days following first positive result. CONCLUSIONS: AN, OP, and SA were effective methods for repeated testing in this population. More AN than OP were positive by viral culture. SA and OP remained RT-PCR-positive longer than AN, which could lead to unnecessary interventions if RT-PCR detection occurred after viral shedding has likely ceased.


Subject(s)
COVID-19 , SARS-CoV-2 , Arkansas , Humans , Nursing Homes , RNA, Viral/genetics
4.
Clin Infect Dis ; 73(Suppl 1): S58-S64, 2021 07 15.
Article in English | MEDLINE | ID: covidwho-1205577

ABSTRACT

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing remains essential for early identification and clinical management of cases. We compared the diagnostic performance of 3 specimen types for characterizing SARS-CoV-2 in infected nursing home residents. METHODS: A convenience sample of 17 residents were enrolled within 15 days of first positive SARS-CoV-2 result by real-time reverse transcription polymerase chain reaction (RT-PCR) and prospectively followed for 42 days. Anterior nasal swabs (AN), oropharyngeal swabs (OP), and saliva specimens (SA) were collected on the day of enrollment, every 3 days for the first 21 days, and then weekly for 21 days. Specimens were tested for presence of SARS-CoV-2 RNA using RT-PCR and replication-competent virus by viral culture. RESULTS: Comparing the 3 specimen types collected from each participant at each time point, the concordance of paired RT-PCR results ranged from 80% to 88%. After the first positive result, SA and OP were RT-PCR-positive for ≤48 days; AN were RT-PCR-positive for ≤33 days. AN had the highest percentage of RT-PCR-positive results (21/26 [81%]) when collected ≤10 days of participants' first positive result. Eleven specimens were positive by viral culture: 9 AN collected ≤19 days following first positive result and 2 OP collected ≤5 days following first positive result. CONCLUSIONS: AN, OP, and SA were effective methods for repeated testing in this population. More AN than OP were positive by viral culture. SA and OP remained RT-PCR-positive longer than AN, which could lead to unnecessary interventions if RT-PCR detection occurred after viral shedding has likely ceased.


Subject(s)
COVID-19 , SARS-CoV-2 , Arkansas , Humans , Nursing Homes , RNA, Viral/genetics
5.
Open Forum Infect Dis ; 8(3): ofab048, 2021 Mar.
Article in English | MEDLINE | ID: covidwho-1135878

ABSTRACT

BACKGROUND: To estimate the infectious period of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in older adults with underlying conditions, we assessed duration of coronavirus disease 2019 (COVID-19) symptoms, reverse-transcription polymerase chain reaction (RT-PCR) positivity, and culture positivity among nursing home residents. METHODS: We enrolled residents within 15 days of their first positive SARS-CoV-2 test (diagnosis) at an Arkansas facility from July 7 to 15, 2020 and instead them for 42 days. Every 3 days for 21 days and then weekly, we assessed COVID-19 symptoms, collected specimens (oropharyngeal, anterior nares, and saliva), and reviewed medical charts. Blood for serology was collected on days 0, 6, 12, 21, and 42. Infectivity was defined by positive culture. Duration of culture positivity was compared with duration of COVID-19 symptoms and RT-PCR positivity. Data were summarized using measures of central tendency, frequencies, and proportions. RESULTS: We enrolled 17 of 39 (44%) eligible residents. Median participant age was 82 years (range, 58-97 years). All had ≥3 underlying conditions. Median duration of RT-PCR positivity was 22 days (interquartile range [IQR], 8-31 days) from diagnosis; median duration of symptoms was 42 days (IQR, 28-49 days). Of 9 (53%) participants with any culture-positive specimens, 1 (11%) severely immunocompromised participant remained culture-positive 19 days from diagnosis; 8 of 9 (89%) were culture-positive ≤8 days from diagnosis. Seroconversion occurred in 12 of 12 (100%) surviving participants with ≥1 blood specimen; all participants were culture-negative before seroconversion. CONCLUSIONS: Duration of infectivity was considerably shorter than duration of symptoms and RT-PCR positivity. Severe immunocompromise may prolong SARS-CoV-2 infectivity. Seroconversion indicated noninfectivity in this cohort.

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