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We describe 10 patients with severe coronavirus disease 2019 (COVID-19) who received tocilizumab and dexamethasone. We correlated isolation duration with cycle thresholds (Ct) values of nucleic acid amplification tests, clinical state and viral cultures. Isolation duration exceeded 21 days for 7 patients due to positive viral cultures or Ct values <30.
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BACKGROUND: COVID-19 is usually a time-limited disease. However, prolonged infections and reinfections can occur among immunocompromised patients. It can be difficult to distinguish a prolonged infection from a new one, especially when reinfection occurs early. METHODS: We report the case of a 57-year-old man infected with SARS-CoV-2 while undergoing chemotherapy for follicular lymphoma. He experienced prolonged symptomatic infection for 3 months despite a 5-day course of remdesivir and eventually deteriorated and died. RESULTS: Viral genome sequencing showed that his final deterioration was most likely due to reinfection. Serologic studies confirmed that the patient did not seroconvert. CONCLUSIONS: This case report highlights that reinfection can occur rapidly (62-67 d) among immunocompromised patients after a prolonged disease. We provide substantial proof of prolonged infection through repeated nucleic acid amplification tests and positive viral culture at day 56 of the disease course, and we put forward evidence of reinfection with viral genome sequencing.
HISTORIQUE: La COVID-19 est généralement une maladie limitée dans le temps. Toutefois, des infections et réinfections prolongées peuvent survenir chez des patients immunodéprimés. Il peut être difficile de distinguer une infection prolongée d'une nouvelle infection, particulièrement lorsque la réinfection se produit rapidement. MÉTHODOLOGIE: Les auteurs rendent compte du cas d'un homme de 57 ans infecté par le SRAS-CoV-2 alors qu'il était sous chimiothérapie pour soigner un lymphome folliculaire. Il a souffert d'une infection symptomatique prolongée de trois mois, malgré un traitement de cinq jours au remdésivir. Son état s'est finalement détérioré et il est décédé. RÉSULTATS: Le séquençage du génome viral a démontré que la détérioration finale de son état a probablement été causée par une réinfection. Les études sérologiques ont confirmé qu'il n'avait pas présenté de séroconversion. CONCLUSIONS: Le présent rapport de cas établit la possibilité d'une réinfection rapide (au bout de 62 à 67 jours) chez les patients immunodéprimés après une longue maladie. Les auteurs fournissent des preuves substantielles d'une infection prolongée par des tests répétés d'amplification des acides nucléiques et par des cultures virales positives au 56e jour de l'évolution de la maladie, et ils présentent des preuves de réinfection grâce au séquençage du génome viral.
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CONTEXTE: La pandémie de COVID-19 a affecté de manière disproportionnée les travailleurs de la santé. Nous avons voulu mesurer la séroprévalence du SRAS-CoV-2 chez les travailleurs de la santé dans les hôpitaux du Québec, au Canada, après la première vague de la pandémie, afin d'explorer les facteurs associés à la SRAS-CoV-2-séropositivité. MÉTHODES: Entre le 6 juillet et le 24 septembre 2020, nous avons recruté des travailleurs de la santé de 10 hôpitaux, dont 8 d'une région où l'incidence de la COVID-19 était élevée (région de Montréal) et 2 de régions du Québec où l'incidence était faible. Les travailleurs de la santé admissibles étaient des médecins, des infirmières, des préposées aux bénéficiaires et des préposés à l'entretien ménager travaillant dans 4 types d'unité de soins (urgences, soins intensifs, unité hospitalière COVID-19 et unité hospitalière non-COVID-19). Les participants ont répondu à un questionnaire et subi un dépistage sérologique du SRAS-CoV-2. Nous avons identifié les facteurs ayant un lien indépendant avec une séroprévalence plus élevée. RÉSULTATS: Parmi les 2056 travailleurs de la santé recrutés, 241 (11,7 %) se sont révélés SRAS-CoV-2-positifs. Parmi eux, 171 (71,0 %) avaient déjà reçu un diagnostic de COVID-19. La séroprévalence a varié d'un hôpital à l'autre, de 2,4 %3,7 % dans les régions où l'incidence était faible, à 17,9 %32,0 % dans les hôpitaux ayant connu des éclosions touchant 5 travailleurs de la santé ou plus. La séroprévalence plus élevée a été associée au fait de travailler dans un hôpital où des éclosions sont survenues (rapport de prévalence ajusté 4,16, intervalle de confiance [IC] à 95 % 2,636,57), au fait d'être infirmière ou auxiliaire (rapport de prévalence ajusté 1,34, IC à 95 % 1,031,74), préposée aux bénéficiaires (rapport de prévalence ajusté 1,49, IC à 95 % 1,121,97) et d'ethnicité noire ou hispanique (rapport de prévalence ajusté 1,41, IC à 95 % 1,131,76). La séroprévalence moindre a été associée au fait de travailler dans une unité de soins intensifs (rapport de prévalence ajusté 0,47, IC à 95 % 0,300,71) ou aux urgences (rapport de prévalence ajusté 0,61, IC à 95 % 0,390,98). INTERPRÉTATION: Les travailleurs de la santé des hôpitaux du Québec ont été exposés à un risque élevé d'infection par le SRAS-CoV-2, particulièrement lors des éclosions. Il faudra travailler à mieux comprendre la dynamique de la transmission du SRAS-CoV-2 dans les milieux de soins.
Subject(s)
Antibodies, Viral/analysis , COVID-19 Serological Testing/methods , COVID-19/epidemiology , Health Personnel/statistics & numerical data , Pandemics , SARS-CoV-2/immunology , Seroepidemiologic Studies , Adult , COVID-19/diagnosis , COVID-19/virology , Cross-Sectional Studies , Female , Follow-Up Studies , Humans , Male , Middle Aged , Quebec/epidemiology , Retrospective StudiesABSTRACT
The objective of this study was to validate the use of spring water gargle (SWG) as an alternative to oral and nasopharyngeal swab (ONPS) for SARS-CoV-2 detection with a laboratory-developed test. Healthcare workers and adults from the general population, presenting to one of two COVID-19 screening clinics in Montréal and Québec City, were prospectively recruited to provide a gargle sample in addition to the standard ONPS. The paired specimens were analyzed using thermal lysis followed by a laboratory-developed nucleic acid amplification test (LD-NAAT) to detect SARS-CoV-2, and comparative performance analysis was performed. An individual was considered infected if a positive result was obtained on either sample. A total of 1297 adult participants were recruited. Invalid results (n = 18) were excluded from the analysis. SARS-CoV-2 was detected in 144/1279 (11.3%) participants: 126 from both samples, 15 only from ONPS, and 3 only from SWG. Overall, the sensitivity was 97.9% (95% CI: 93.7-99.3) for ONPS and 89.6% (95% CI: 83.4-93.6; p = 0.005) for SWG. The mean ONPS cycle threshold (Ct ) value was significantly lower for the concordant paired samples as compared to discordant ones (22.9 vs. 32.1; p < 0.001). In conclusion, using an LD-NAAT with thermal lysis, SWG is a less sensitive sampling method than the ONPS. However, the higher acceptability of SWG might enable a higher rate of detection from a population-based perspective. Nonetheless, in patients with a high clinical suspicion of COVID-19, a repeated analysis with ONPS should be considered. The sensitivity of SWG using NAAT preceded by chemical extraction should be evaluated.
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COVID-19 , Natural Springs , Adult , COVID-19/diagnosis , Humans , Mouthwashes , Nasopharynx , SARS-CoV-2/genetics , Saliva , Specimen Handling/methods , WaterABSTRACT
BACKGROUND: This PRONTO study investigated the clinical performance of the Abbott ID NOWTM (IDN) COVID-19 diagnostic assay used at point of care and its impact on turnaround time for divulgation of test results. METHODS: Prospective study conducted from December 2020 to February 2021 in acute symptomatic participants presenting in three walk-in centres in the province of Québec. RESULTS: Valid paired samples were obtained from 2,372 participants. A positive result on either the IDN or the standard-of-care nucleic acid amplification test (SOC-NAAT) was obtained in 423 participants (prevalence of 17.8%). Overall sensitivity of IDN and SOC-NAAT were 96.4% (95% CI: 94.2-98.0%) and 99.1% (95% CI: 97.6-99.8), respectively; negative predictive values were 99.2% (95% CI: 98.7-99.6%) and 99.8% (95% CI: 99.5-100%), respectively. Turnaround time for positive results was significantly faster on IDN. CONCLUSION: In our experience, IDN use in symptomatic individuals in walk-in centres is a reliable sensitive alternative to SOC-NAAT without the need for subsequent confirmation of negative results. Such deployment can accelerate contact tracing, reduce the burden on laboratories and increase access to testing.
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BACKGROUND: The COVID-19 pandemic has disproportionately affected health care workers. We sought to estimate SARS-CoV-2 seroprevalence among hospital health care workers in Quebec, Canada, after the first wave of the pandemic and to explore factors associated with SARS-CoV-2 seropositivity. METHODS: Between July 6 and Sept. 24, 2020, we enrolled health care workers from 10 hospitals, including 8 from a region with a high incidence of COVID-19 (the Montréal area) and 2 from low-incidence regions of Quebec. Eligible health care workers were physicians, nurses, orderlies and cleaning staff working in 4 types of care units (emergency department, intensive care unit, COVID-19 inpatient unit and non-COVID-19 inpatient unit). Participants completed a questionnaire and underwent SARS-CoV-2 serology testing. We identified factors independently associated with higher seroprevalence. RESULTS: Among 2056 enrolled health care workers, 241 (11.7%) had positive SARS-CoV-2 serology. Of these, 171 (71.0%) had been previously diagnosed with COVID-19. Seroprevalence varied among hospitals, from 2.4% to 3.7% in low-incidence regions to 17.9% to 32.0% in hospitals with outbreaks involving 5 or more health care workers. Higher seroprevalence was associated with working in a hospital where outbreaks occurred (adjusted prevalence ratio 4.16, 95% confidence interval [CI] 2.63-6.57), being a nurse or nursing assistant (adjusted prevalence ratio 1.34, 95% CI 1.03-1.74) or an orderly (adjusted prevalence ratio 1.49, 95% CI 1.12-1.97), and Black or Hispanic ethnicity (adjusted prevalence ratio 1.41, 95% CI 1.13-1.76). Lower seroprevalence was associated with working in the intensive care unit (adjusted prevalence ratio 0.47, 95% CI 0.30-0.71) or the emergency department (adjusted prevalence ratio 0.61, 95% CI 0.39-0.98). INTERPRETATION: Health care workers in Quebec hospitals were at high risk of SARS-CoV-2 infection, particularly in outbreak settings. More work is needed to better understand SARS-CoV-2 transmission dynamics in health care settings.
Subject(s)
COVID-19/epidemiology , Occupational Diseases/epidemiology , SARS-CoV-2 , COVID-19/blood , COVID-19/etiology , Cross-Sectional Studies , Demography , Health Personnel , Hospitals , Humans , Incidence , Occupational Diseases/blood , Occupational Diseases/etiology , Pandemics , Quebec/epidemiology , Risk Factors , Seroepidemiologic Studies , Surveys and QuestionnairesABSTRACT
BACKGROUND: Nasopharyngeal swab has long been considered the specimen of choice for the diagnosis of respiratory viral infections, including SARS-CoV-2 infection, but it suffers from several drawbacks: its discomfort limits screening acceptability, and it is vulnerable to shortages in both specialized materials and trained healthcare workers in the context of a pandemic. METHODS: We prospectively compared natural spring water gargle to combined oro-nasopharyngeal swab (ONPS) for the diagnosis of coronavirus disease 2019 (COVID-19) in paired clinical specimens (1005 ONPS and 1005 gargles) collected from 987 unique early symptomatic as well as asymptomatic individuals from the community. RESULTS: Using a direct RT-PCR method with the Allplex™ 2019-nCoV Assay (Seegene), the clinical sensitivity of the gargle was 95.3% (95% confidence interval [CI], 90.2 - 98.3%), similar to the sensitivity of the ONPS (93.8%; 95% CI, 88.2 - 97.3%), despite significantly lower viral RNA concentration in gargles, as reflected by higher cycle threshold values. No single specimen type detected all COVID-19 cases. SARS-CoV-2 RNA was stable in gargles at room temperature for at least 7 days. CONCLUSION: The simplicity of this sampling method coupled with the accessibility of spring water are clear advantages in a pandemic situation where testing frequency, turnaround time and shortage of consumables and trained staff are critical elements.
Subject(s)
COVID-19 , RNA, Viral , Humans , Nasopharynx , RNA, Viral/genetics , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2 , Saliva , Specimen Handling , WaterABSTRACT
The accurate laboratory detection of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a crucial element in the fight against coronavirus disease 2019 (COVID-19). Reverse transcription-polymerase chain reaction testing on combined oral and nasopharyngeal swab (ONPS) suffers from several limitations, including the need for qualified personnel, the discomfort caused by invasive nasopharyngeal sample collection, and the possibility of swab and transport media shortage. Testing on saliva would represent an advancement. The aim of this study was to compare the concordance between saliva samples and ONPS for the detection of SARS-CoV-2 on various commercial and laboratory-developed tests (LDT). Individuals were recruited from eight institutions in Quebec, Canada, if they had SARS-CoV-2 RNA detected on a recently collected ONPS, and accepted to provide another ONPS, paired with saliva. Assays available in the different laboratories (Abbott RealTime SARS-CoV-2, Cobas® SARS-CoV-2, Simplexa™ COVID-19 Direct, Allplex™ 2019-nCoV, RIDA®GENE SARS-CoV-2, and an LDT preceded by three different extraction methods) were used to determine the concordance between saliva and ONPS results. Overall, 320 tests were run from a total of 125 saliva and ONPS sample pairs. All assays yielded similar sensitivity when saliva was compared to ONPS, with the exception of one LDT (67% vs. 93%). The mean difference in cycle threshold (∆C t ) was generally (but not significantly) in favor of the ONPS for all nucleic acid amplification tests. The maximum mean ∆âââââC t was 2.0, while individual ∆C t varied importantly from -17.5 to 12.4. Saliva seems to be associated with sensitivity similar to ONPS for the detection of SARS-CoV-2 by various assays.