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1.
J Infect Dis ; 222(4): 551-555, 2020 07 23.
Article in English | MEDLINE | ID: covidwho-704462

ABSTRACT

We simulated 3 transmission modes, including close-contact, respiratory droplets and aerosol routes, in the laboratory. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can be highly transmitted among naive human angiotensin-converting enzyme 2 (hACE2) mice via close contact because 7 of 13 naive hACE2 mice were SARS-CoV-2 antibody seropositive 14 days after being introduced into the same cage with 3 infected-hACE2 mice. For respiratory droplets, SARS-CoV-2 antibodies from 3 of 10 naive hACE2 mice showed seropositivity 14 days after introduction into the same cage with 3 infected-hACE2 mice, separated by grids. In addition, hACE2 mice cannot be experimentally infected via aerosol inoculation until continued up to 25 minutes with high viral concentrations.


Subject(s)
Betacoronavirus , Coronavirus Infections/transmission , Pneumonia, Viral/transmission , Aerosols , Anal Canal/virology , Animals , Antibodies, Viral/blood , Betacoronavirus/genetics , Betacoronavirus/immunology , Betacoronavirus/isolation & purification , Chlorocebus aethiops , Female , Humans , Immunoglobulin G/blood , Lung/pathology , Lung/virology , Male , Mice , Mice, Transgenic , Pandemics , Peptidyl-Dipeptidase A/genetics , Pharynx/virology , RNA, Viral/isolation & purification , Respiratory System/virology , Risk , Specific Pathogen-Free Organisms , Time Factors , Vero Cells , Viral Load , Weight Loss
2.
J Infect Dis ; 222(2): 194-197, 2020 06 29.
Article in English | MEDLINE | ID: covidwho-641903

ABSTRACT

We report a case series of 6 patients with confirmed coronavirus disease 2019 (COVID-19) in Wakayama prefecture, Japan. All 6 of the patients tested positive via pharyngeal swab polymerase chain reaction (PCR) tests, and 2 of the 6 were still positive at 3 weeks after onset. All of the patients exhibited bilateral ground glass opacities on computed tomography (CT). This article also reports narrative information on the spectrum of symptoms collected directly from the patients. It would be difficult to triage patients with COVID-19 based on the typical symptoms of fever and/or cough, although PCR and CT are definitive in diagnosis.


Subject(s)
Betacoronavirus , Coronavirus Infections , Pandemics , Pneumonia, Viral , Adult , Aged , Aged, 80 and over , Clinical Laboratory Techniques , Coronavirus Infections/diagnosis , Coronavirus Infections/diagnostic imaging , Coronavirus Infections/physiopathology , Cough , Female , Fever , Humans , Japan , Lung/diagnostic imaging , Male , Middle Aged , Pharynx/virology , Pneumonia, Viral/diagnosis , Pneumonia, Viral/diagnostic imaging , Pneumonia, Viral/physiopathology , Polymerase Chain Reaction , Tomography, X-Ray Computed
4.
Clin Gastroenterol Hepatol ; 18(8): 1753-1759.e2, 2020 07.
Article in English | MEDLINE | ID: covidwho-613156

ABSTRACT

BACKGROUND & AIMS: We compared clinical, laboratory, radiological, and outcome features of patients with SARS-CoV-2 infection (COVID-19) with pneumonia, with vs without diarrhea. METHODS: We performed a retrospective, single-center analysis of 84 patients with SARS-CoV-2 pneumonia in Wuhan Union Hospital, China, from January 19 through February 7, 2020. Cases were confirmed by real-time reverse-transcriptase PCR of nasal and pharyngeal swab specimens for SARS-CoV-2 RNA. Blood samples were analyzed for white blood cell count, lymphocyte count, alanine aminotransferase, creatine kinase, lactate dehydrogenase, D-dimer, C-reactive protein, and in some cases, immunoglobulins, complement, lymphocyte subsets, and cytokines. Virus RNA was detected in stool samples by real-time PCR. RESULTS: Of the 84 patients with SARS-CoV-2 pneumonia, 26 (31%) had diarrhea. The duration of fever and dyspnea in patients with diarrhea was significantly longer than those without diarrhea (all P < .05). Stool samples from a higher proportion of patients with diarrhea tested positive for virus RNA (69%) than from patients without diarrhea (17%) (P < .001). As of February 19, a lower proportion of patients with diarrhea had a negative result from the latest throat swab for SARS-CoV-2 (77%) than patients without diarrhea (97%) (P = .010), during these patients' hospitalization. Of 76 patients with a negative result from their latest throat swab test during hospitalization, a significantly higher proportion of patients with diarrhea had a positive result from the retest for SARS-CoV-2 in stool (45%) than patients without diarrhea (20%) (P = .039). CONCLUSIONS: At a single center in Wuhan, China, 31% of patients with SARS-CoV-2 pneumonia had diarrhea. A significantly higher proportion of patients with diarrhea have virus RNA in stool than patients without diarrhea. Elimination of SARS-CoV-2 from stool takes longer than elimination from the nose and throat.


Subject(s)
Betacoronavirus/isolation & purification , Carrier State/virology , Coronavirus Infections/complications , Coronavirus Infections/pathology , Diarrhea/epidemiology , Diarrhea/etiology , Pneumonia, Viral/complications , Pneumonia, Viral/pathology , Adult , Aged , Blood Cell Count , Blood Chemical Analysis , China , Diarrhea/pathology , Feces/virology , Female , Hospitals , Humans , Male , Middle Aged , Nasal Mucosa/virology , Pandemics , Pharynx/virology , RNA, Viral/analysis , Real-Time Polymerase Chain Reaction , Retrospective Studies , Young Adult
5.
BMC Infect Dis ; 20(1): 429, 2020 Jun 19.
Article in English | MEDLINE | ID: covidwho-608211

ABSTRACT

BACKGROUND: Since December 2019, over 80,000 patients with coronavirus disease 2019 (COVID-19) have been confirmed in China. With the increasing number of recovered patients, more attention should be paid to the follow-up of these patients. METHODS: In the study, 576 patients with COVID-19 discharged from hospital in Chongqing, China from January 24, 2020, to March 10, 2020 were evaluated by viral nucleic acid tests for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) to determine if they could be released from quarantine. Among the 576 patients, 61 patients (10.6%) had positive RT-PCR test results of SARS-CoV-2. We aimed to analyze the demographics, clinical characteristics and treatment of 61 patients. RESULTS: These positive patients were characterized by older age, chronic medical illness and mild conditions. 38 (62.3%) patients who were asymptomatic without abnormalities on chest radiographs were found in the positive with COVID-19. Also, they showed positive results of stool or sputum specimens with negative results of nasal and pharyngeal swab specimens. The median duration of positive result of SARS-CoV-2 was varied from 3 days to 35 days in the patients discharged from hospital with no family member infection. CONCLUSIONS: Multi-site screening of SARS-CoV-2 including nasal and pharyngeal swabs, stool and sputum specimens could be considered to improve the diagnosis, treatment and infection control in patients with COVID-19. Our findings provide the important information and clinical evidence for the improved management of patients recovered from COVID-19.


Subject(s)
Coronavirus Infections/diagnosis , Patient Discharge , Pneumonia, Viral/diagnosis , Adult , Aged , Betacoronavirus , China , Clinical Laboratory Techniques , Feces/virology , Female , Humans , Male , Middle Aged , Nose/virology , Pandemics , Pharynx/virology , RNA, Viral/isolation & purification , Sputum/virology
6.
Exp Mol Med ; 52(6): 963-977, 2020 06.
Article in English | MEDLINE | ID: covidwho-601243

ABSTRACT

SARS-CoV-2 is very contagious and has rapidly spread globally. Due to various symptomatic and asymptomatic cases and the possibility of asymptomatic transmission, there is a pressing need for a fast and sensitive detection protocol to diagnose asymptomatic people. Various SARS-CoV-2 diagnostic kits are already available from many companies and national health agencies. However, publicly available information on these diagnostic kits is lacking. In response to the growing need and the lack of information, we developed and made available a low-cost, easy-access, real-time PCR-based protocol for the early detection of the virus in a previous study. During the development of the detection protocol, we found that unoptimized primer sets could inadvertently show false-positive results, raising the possibility that commercially available diagnostic kits might also contain primer sets that produce false-positive results. Here, we provide three-step guidelines for the design and optimization of specific primer sets. The three steps include (1) the selection of primer sets for target genes (RdRP, N, E, and S) in the genome of interest (SARS-CoV-2), (2) the in silico validation of primer and amplicon sequences, and (3) the optimization of PCR conditions (i.e., primer concentrations and annealing temperatures) for specific hybridization between the primers and target genes, and the elimination of spurious primer dimers. Furthermore, we have expanded the previously developed real-time PCR-based protocol to more conventional PCR-based protocols and applied a multiplex PCR-based protocol that allows the simultaneous testing of primer sets for RdRP, N, E, and S all in one reaction. Our newly optimized protocol should be helpful for the large-scale, high-fidelity screening of asymptomatic people, even without any high-specification equipment, for the further prevention of transmission, and to achieve early intervention and treatment for the rapidly propagating virus.


Subject(s)
Betacoronavirus/genetics , Clinical Laboratory Techniques/methods , Coronavirus Infections/virology , DNA Primers , Pneumonia, Viral/virology , Polymerase Chain Reaction/methods , Coronavirus Infections/diagnosis , HEK293 Cells , Humans , Multiplex Polymerase Chain Reaction/methods , Pandemics , Pharynx/virology , Pneumonia, Viral/diagnosis , RNA Replicase/genetics , Real-Time Polymerase Chain Reaction/methods , SARS Virus/genetics , Spike Glycoprotein, Coronavirus/genetics , Viral Nonstructural Proteins/genetics , Viral Proteins/genetics
7.
J Clin Microbiol ; 58(8)2020 07 23.
Article in English | MEDLINE | ID: covidwho-592313

ABSTRACT

Real-time reverse transcription-PCR (RT-PCR) is currently the most sensitive method to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes coronavirus disease 2019 (COVID-19). However, the correlation between detectable viral RNA and culturable virus in clinical specimens remains unclear. Here, we performed virus culture for 60 specimens that were confirmed to be positive for SARS-CoV-2 RNA by real-time RT-PCR. The virus could be successfully isolated from 12 throat and nine nasopharyngeal swabs and two sputum specimens. The lowest copy number required for virus isolation was determined to be 5.4, 6.0, and 5.7 log10 genome copies/ml sample for detecting the nsp12, E, and N genes, respectively. We further examined the correlation of genome copy number and virus isolation in different regions of the viral genome, demonstrating that culturable specimens are characterized by high copy numbers with a linear correlation observed between copy numbers of amplicons targeting structural and nonstructural regions. Overall, these results indicate that in addition to the copy number, the integrity of the viral genome should be considered when evaluating the infectivity of clinical SARS-CoV-2 specimens.


Subject(s)
Betacoronavirus/growth & development , Betacoronavirus/isolation & purification , Clinical Laboratory Techniques/methods , Coronavirus Infections/diagnosis , Coronavirus Infections/virology , Pneumonia, Viral/diagnosis , Pneumonia, Viral/virology , Virus Cultivation/methods , Betacoronavirus/genetics , Correlation of Data , Humans , Nasopharynx/virology , Pandemics , Pharynx/virology , Real-Time Polymerase Chain Reaction/methods , Reverse Transcriptase Polymerase Chain Reaction/methods
9.
Eur Rev Med Pharmacol Sci ; 24(10): 5772-5777, 2020 May.
Article in English | MEDLINE | ID: covidwho-542647

ABSTRACT

OBJECTIVE: It has recently been reported that some COVID-19 patients have long-term positive fecal nucleic acid after discharging from the hospital with negative nucleic acid in the respiratory tract, but it is unclear whether COVID-19 patients with positive long-term fecal nucleic acid tests have the risk of self-infection. PATIENTS AND METHODS: From January 25, 2020 to March 9, 2020, 5 COVID-19 patients with negative respiratory tract nucleic acid and positive fecal nucleic acid were observed and studied to explore whether these patients can re-infect themselves. Five patients with COVID-19 accompanied by diarrhea as the main gastrointestinal symptoms were carefully observed through clinical symptoms, imaging and other auxiliary examinations. The RT-PCR technology was used to continuously detect fecal and respiratory viral nucleic acids. The IgM antibody was detected on the 7th day of admission and IgM/IgG at the time of discharge. RESULTS: All 5 patients had symptoms of fever and diarrhea upon admission. The fecal nucleic acid was positive, as well as the throat swab was positive. All COVID-19 patients had positive IgM antibodies on the 7th day of admission and positive IgM and IgG at the time of discharge, and there were no abnormalities in the gastrointestinal examination on discharge. All 5 fecal nucleic acid tests were positive at the time of discharge. After continuous dynamic follow-up for 3-15 days, no clinical symptoms recurred, and the last nucleic acid test was negative. CONCLUSIONS: There is no risk of self-infection for COVID-19 patients with long-term 2019-nCoV nucleic acid positive in feces.


Subject(s)
Betacoronavirus/genetics , Coronavirus Infections/diagnosis , Feces/virology , Pneumonia, Viral/diagnosis , RNA, Viral/analysis , Adult , Betacoronavirus/immunology , Betacoronavirus/isolation & purification , Coronavirus Infections/virology , Female , Humans , Immunoglobulin G/blood , Immunoglobulin M/blood , Male , Middle Aged , Pandemics , Patient Discharge , Pharynx/virology , Pneumonia, Viral/virology , RNA, Viral/genetics , RNA, Viral/metabolism , Recurrence , Tomography, X-Ray Computed
10.
Indian J Med Res ; 151(5): 438-443, 2020 May.
Article in English | MEDLINE | ID: covidwho-453637

ABSTRACT

Background & objectives: A cluster of SARS-CoV-2 infection occurred among Italian tourists visiting India. We report here the epidemiological, clinical, radiological and laboratory findings of the first cluster of SARS-CoV-2 infection among the tourists. Methods: Information was collected on demographic details, travel and exposure history, comorbidities, timelines of events, date of symptom onset and duration of hospitalization from the 16 Italian tourists and an Indian with laboratory-confirmed SARS-CoV-2 infection. The clinical, laboratory, radiologic and treatment data was abstracted from their medical records and all tourists were followed up till their recovery or discharge or death. Throat and deep nasal swab specimens were collected on days 3, 8, 15, 18, 23 and 25 to evaluate viral clearance. Results: A group of 23 Italian tourists reached New Delhi, India, on February 21, 2020 and along with three Indians visited several tourist places in Rajasthan. By March 3, 2020, 17 of the 26 (attack rate: 65.4%) had become positive for SARS-CoV-2 infection. Of these 17 patients, nine were symptomatic, while eight did not show any symptoms. Of the nine who developed symptoms, six were mild, one was severe and two were critically ill. The median duration between the day of confirmation for COVID-19 and RT-PCR negativity was 18 days (range: 12-23 days). Two patients died with a case fatality of 11.8 per cent. Interpretation & conclusions: This study reconfirms higher rates of transmission among close contacts and therefore, public health measures such as physical distancing, personal hygiene and infection control measures are necessary to prevent transmission.


Subject(s)
Asymptomatic Infections/epidemiology , Betacoronavirus , Coronavirus Infections/epidemiology , Coronavirus Infections/therapy , Pneumonia, Viral/epidemiology , Pneumonia, Viral/therapy , Aged , Betacoronavirus/genetics , Cluster Analysis , Coronavirus Infections/diagnosis , Coronavirus Infections/transmission , Critical Illness , Fatal Outcome , Female , Humans , India/epidemiology , Italy/ethnology , Male , Nasal Cavity/virology , Pandemics , Patient Acuity , Pharynx/virology , Pneumonia, Viral/diagnosis , Pneumonia, Viral/transmission , RNA, Viral/analysis , Reverse Transcriptase Polymerase Chain Reaction , Travel
12.
Indian J Ophthalmol ; 68(6): 1015-1017, 2020 06.
Article in English | MEDLINE | ID: covidwho-401251

ABSTRACT

Purpose: To detect the presence of viral RNA of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in conjunctival swab specimens of coronavirus disease-19 (COVID-19) patients. Methods: Forty-five COVID-19 patients positive for real-time reverse transcription-polymerase chain reaction (RT-PCR) for SARS-CoV-2 in nasopharyngeal swab with or without ocular manifestations were included in the study. The conjunctival swab of each patient was collected by an ophthalmologist posted for COVID duty. Results: Out of 45 patients, 35 (77.77%) were males and the rest were females. The mean age was 31.26 ± 12.81 years. None of the patients had any ocular manifestations. One (2.23%) out of 45 patients was positive for RT-PCR SARS-CoV-2 in the conjunctival swab. Conclusion: This study shows that SARS-CoV-2 can be detected in conjunctival swabs of confirmed cases of COVID-19 patients. Though the positivity rate of detecting SARS-CoV-2 in conjunctival swabs is very less, care should be exercised during the ocular examination of patients of COVID-19.


Subject(s)
Betacoronavirus/genetics , Conjunctivitis, Viral/diagnosis , Coronavirus Infections/diagnosis , Pneumonia, Viral/diagnosis , RNA, Viral/isolation & purification , Adolescent , Adult , Child , Clinical Laboratory Techniques , Female , Humans , Male , Middle Aged , Nasal Cavity/virology , Pandemics , Pharynx/virology , Prospective Studies , Real-Time Polymerase Chain Reaction , Specimen Handling , Young Adult
13.
J Infect Dis ; 222(4): 551-555, 2020 07 23.
Article in English | MEDLINE | ID: covidwho-343436

ABSTRACT

We simulated 3 transmission modes, including close-contact, respiratory droplets and aerosol routes, in the laboratory. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can be highly transmitted among naive human angiotensin-converting enzyme 2 (hACE2) mice via close contact because 7 of 13 naive hACE2 mice were SARS-CoV-2 antibody seropositive 14 days after being introduced into the same cage with 3 infected-hACE2 mice. For respiratory droplets, SARS-CoV-2 antibodies from 3 of 10 naive hACE2 mice showed seropositivity 14 days after introduction into the same cage with 3 infected-hACE2 mice, separated by grids. In addition, hACE2 mice cannot be experimentally infected via aerosol inoculation until continued up to 25 minutes with high viral concentrations.


Subject(s)
Betacoronavirus , Coronavirus Infections/transmission , Pneumonia, Viral/transmission , Aerosols , Anal Canal/virology , Animals , Antibodies, Viral/blood , Betacoronavirus/genetics , Betacoronavirus/immunology , Betacoronavirus/isolation & purification , Chlorocebus aethiops , Female , Humans , Immunoglobulin G/blood , Lung/pathology , Lung/virology , Male , Mice , Mice, Transgenic , Pandemics , Peptidyl-Dipeptidase A/genetics , Pharynx/virology , RNA, Viral/isolation & purification , Respiratory System/virology , Risk , Specific Pathogen-Free Organisms , Time Factors , Vero Cells , Viral Load , Weight Loss
14.
J Stroke Cerebrovasc Dis ; 29(9): 104981, 2020 Sep.
Article in English | MEDLINE | ID: covidwho-342995

ABSTRACT

Coronavirus disease 19 (COVID-19) is an emerging infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this scenario, managing acute medical conditions, such as stroke, requires a timely treatment together with proper strategies that minimize the risk of infection spreading to health care workers and other patients. We report the case of a 79-year-old woman, who was admitted for a wake-up stroke due to occlusion of the left middle cerebral artery. She was treated outside the COVID-19-dedicated track of the hospital because she had no concomitant signs or symptoms suggestive of SARS-CoV-2 infection nor recent contact with other infected individuals. Post-mortem nasal and pharyngeal swab was positive for SARS-CoV-2 infection. We propose that hyperacute stroke patients should be tested for SARS-CoV-2 infection at admission and then managed as having COVID-19 until cleared by a negative result. We are aware that such measure results in some delay of the acute treatment of stroke, which could be minimal using well-exercised containment protocols.


Subject(s)
Betacoronavirus/isolation & purification , Clinical Laboratory Techniques , Coronavirus Infections/diagnosis , Infarction, Middle Cerebral Artery/therapy , Nose/virology , Pharynx/virology , Pneumonia, Viral/diagnosis , Aged , Coronavirus Infections/transmission , Coronavirus Infections/virology , Delayed Diagnosis , Fatal Outcome , Female , Humans , Infarction, Middle Cerebral Artery/diagnosis , Infarction, Middle Cerebral Artery/physiopathology , Infectious Disease Transmission, Patient-to-Professional/prevention & control , Occupational Exposure/adverse effects , Pandemics , Pneumonia, Viral/transmission , Pneumonia, Viral/virology , Predictive Value of Tests , Risk Factors , Severity of Illness Index
15.
Eur Respir J ; 56(1)2020 07.
Article in English | MEDLINE | ID: covidwho-324587

ABSTRACT

BACKGROUND: The duration of viral shedding is central to the guidance of decisions about isolation precautions and antiviral treatment. However, studies regarding the risk factors associated with prolonged shedding of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the impact of lopinavir/ritonavir (LPV/r) treatment on viral shedding remain scarce. METHODS: Data were collected from all SARS-CoV-2 infected patients who were admitted to isolation wards and had reverse transcription PCR conversion at the No. 3 People's Hospital of Hubei province, China, between 31 January and 9 March 2020. We compared clinical characteristics and SARS-CoV-2 RNA shedding between patients initiated with LPV/r treatment and those without. Logistic regression analysis was employed to evaluate the risk factors associated with prolonged viral shedding. RESULTS: Of 120 patients, the median age was 52 years, 54 (45%) were male and 78 (65%) received LPV/r treatment. The median duration of SARS-CoV-2 RNA detection from symptom onset was 23 days (interquartile range 18-32 days). Older age (OR 1.03, 95% CI 1.00-1.05; p=0.03) and the lack of LPV/r treatment (OR 2.42, 95% CI 1.10-5.36; p=0.029) were independent risk factors for prolonged SARS-CoV-2 RNA shedding. Patients who initiated LPV/r treatment within 10 days from symptom onset, but not initiated from day 11 onwards, had significantly shorter viral shedding duration compared with those without LPV/r treatment (median 19 days versus 28.5 days; log-rank p<0.001). CONCLUSION: Older age and the lack of LPV/r treatment were independently associated with prolonged SARS-CoV-2 RNA shedding in patients with coronavirus disease 2019 (COVID-19). Earlier administration of LPV/r treatment could shorten viral shedding duration.


Subject(s)
Antiviral Agents/therapeutic use , Coronavirus Infections/drug therapy , Lopinavir/therapeutic use , Pneumonia, Viral/drug therapy , Ritonavir/therapeutic use , Virus Shedding , Adult , Age Factors , Aged , Betacoronavirus , Case-Control Studies , Drug Combinations , Female , Hospitalization , Humans , Male , Middle Aged , Pandemics , Pharynx/virology , RNA, Viral , Real-Time Polymerase Chain Reaction , Retrospective Studies , Reverse Transcriptase Polymerase Chain Reaction , Time Factors
16.
J Infect Chemother ; 26(8): 851-853, 2020 Aug.
Article in English | MEDLINE | ID: covidwho-308545

ABSTRACT

We here report a case of coronavirus disease-19 (COVID-19) in Japan in which the initial throat swab polymerase chain reaction result was negative The possibility of false-negative results in the early phase of disease suggest reconsideration of the feasibility of a community or national infection control framework to prevent transmission. We recommend establishing an alternative feasible system, such as self-isolation by contact history in non-endemic community and by symptoms in endemic community, not relying on the PCR examination, to minimize this ongoing COVID-19 outbreak. Further rapid accumulation of knowledge including incubation period, clinical course and types of transmission is warranted to control this outbreak.


Subject(s)
Betacoronavirus/isolation & purification , Clinical Laboratory Techniques , Coronavirus Infections/diagnosis , Pharynx/virology , Pneumonia, Viral/diagnostic imaging , Betacoronavirus/genetics , China , Coronavirus Infections/complications , False Negative Reactions , Female , Humans , Japan , Middle Aged , Pandemics , Pneumonia, Viral/complications , Pneumonia, Viral/diagnosis , Pneumonia, Viral/virology , Polymerase Chain Reaction , Travel
17.
J Infect Dis ; 222(2): 203-205, 2020 06 29.
Article in English | MEDLINE | ID: covidwho-306065

ABSTRACT

The detection of SARS-CoV-2 infection is the premise of quarantine. In many countries or areas, samples need to be shipped or inactivated before SARS-CoV-2 testing. In this study, we checked the influence of sample storage conditions on SARS-CoV-2 nucleic acid testing results, including sample inactivation time, storage temperature, and storage time. All of these conditions caused an increase in the cycle threshold values of the nucleic acid tests and led to the misclassification of at least 10.2% of positive cases as negative or suspected. The results highlight the importance of immediate testing of samples for SARS-CoV-2 nucleic acid detection.


Subject(s)
Betacoronavirus , Clinical Laboratory Techniques , Coronavirus Infections/diagnosis , Pharynx/virology , Pneumonia, Viral/diagnosis , Specimen Handling/methods , Betacoronavirus/genetics , Cryopreservation , Freezing , Humans , Pandemics , Refrigeration , Reverse Transcriptase Polymerase Chain Reaction , Temperature , Time Factors , Virus Inactivation
18.
Emerg Microbes Infect ; 9(1): 1233-1237, 2020 Dec.
Article in English | MEDLINE | ID: covidwho-291196

ABSTRACT

Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) assay on anal swabs was recently reported to be persistently positive even after throat testing was negative during severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, data about the consistent performance of RT-PCR assay on throat and anal swabs remain limited in paediatric patients. Here, we retrospectively reviewed RT-PCR-testing results of 212 paediatric patients with suspected SARS-CoV-2 infection at Wuhan Children's Hospital. The diagnostic potential of these two types of specimens showed significant difference (positive rate: 78.2% on throat swabs vs. 52.6% on anal swabs, McNemar Test P = 0.0091) and exhibited a weak positive consistency (Kappa value was 0.311, P < 0.0001) in paediatric patients. Furthermore, viral loads detected on both throat and anal swabs also showed no significant difference (P = 0.9511) and correlation (Pearson r = 0.0434, P = 0.8406), and exhibited an inconsistent kinetic change through the course of SARS-CoV-2 infection. Besides, viral loads in the throat and anal swabs were correlated with different types of immune states, immune-reactive phase, and the resolution phase/immunologic tolerance, respectively. These findings revealed that RT-PCR-testing on throat and anal swabs showed significant difference for monitoring SARS-CoV-2 infection and correlated with different immune state in paediatric patients.


Subject(s)
Anal Canal/virology , Betacoronavirus/isolation & purification , Coronavirus Infections/virology , Pharynx/virology , Pneumonia, Viral/virology , Viral Load , Betacoronavirus/genetics , Child , China/epidemiology , Coronavirus Infections/diagnosis , Coronavirus Infections/epidemiology , Female , Humans , Male , Pandemics , Pneumonia, Viral/diagnosis , Pneumonia, Viral/epidemiology , Real-Time Polymerase Chain Reaction/standards , Retrospective Studies
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