Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 19 de 19
Filter
2.
Infect Dis Poverty ; 11(1): 56, 2022 May 16.
Article in English | MEDLINE | ID: covidwho-1846872

ABSTRACT

BACKGROUND: Safety data reported from the large-scale clinical trials of the coronavirus disease 2019 (COVID-19) vaccine are extremely limited in patients with decompensated cirrhosis. The vaccination campaign in this specific population could be difficult due to uncertainty about the adverse events following vaccination. We aimed to assessed the COVID-19 vaccination rate, factors associated with unvaccinated status, and the adverse events following vaccination in patients with decompensated cirrhosis. METHODS: This is a retrospective study from Ruijin Hospial (Shanghai, China) on an ongoing prospective cohort designed for long-term survival analysis of decompensated cirrhotic patients who recovered from decompensating events or acute-on-chronic liver failure (ACLF) between 2016 and 2018. We assessed the COVID-19 vaccination rate, the number of doses, type of vaccine, safety data, patient-reported reasons for remaining unvaccinated, factors associated with unvaccinated status, and the adverse events of COVID-19 vaccine. Binary logistic regression was used for identifying factors associated with unvaccinated status. RESULTS: A total of 229 patients with decompensated cirrhosis without previous SARS-CoV-2 infection participated (mean age, 56 ± 12.2 years, 75% male, 65% viral-related cirrhosis). Mode of decompensation were grade II‒III ascites (82.5%), gastroesophageal varices bleeding (7.9%), hepatic encephalopathy (7.9%). Eighty-five participants (37.1%) received at least one dose of vaccination (1 dose: n = 1, 2 doses: n = 65, 3 doses: n = 19) while 62.9% remained unvaccinated. Patient-reported reasons for remaining unvaccinated were mainly fear of adverse events (37.5%) and lack of positive advice from healthcare providers (52.1%). The experience of hepatic encephalopathy (OR = 5.61, 95% CI: 1.24-25.4) or ACLF (OR = 3.13, 95% CI: 1.12-8.69) and post-liver transplantation status (OR = 2.47, 95% CI: 1.06-5.76) were risk factors of remaining unvaccinated independent of residential areas. The safety analysis demonstrated that 75.3% had no adverse events, 23.6% had non-severe reactions (20% injection-site pain, 1.2% fatigue, 2.4% rash) and 1.2% had a severe event (development of acute decompensation requiring hospitalization). CONCLUSIONS: Patients with decompensated cirrhosis in eastern China are largely remained at unvaccinated status, particularly those with previous episodes of ACLF or hepatic encephalopathy and liver transplantation recipients. Vaccination against COVID-19 in this population is safe.


Subject(s)
COVID-19 , Hepatic Encephalopathy , Vaccines , Adult , Aged , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , China/epidemiology , Female , Hepatic Encephalopathy/complications , Humans , Liver Cirrhosis/complications , Male , Middle Aged , Prospective Studies , Retrospective Studies , Risk Factors , SARS-CoV-2
3.
Influenza Other Respir Viruses ; 2022 Apr 29.
Article in English | MEDLINE | ID: covidwho-1822050

ABSTRACT

Based on our national outpatient sentinel surveillance, we have developed a novel approach to determine respiratory syncytial virus (RSV) epidemic seasons in Germany by using RSV positivity rate and its lower limit of 95% confidence interval. This method was evaluated retrospectively on nine RSV seasons, and it is also well-suited to describe off-season circulation of RSV in near real time as observed for seasons 2020/21 and 2021/22 during the COVID-19 pandemic. Prospective application is of crucial importance to enable timely actions for health service delivery and prevention.

4.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-321465

ABSTRACT

Background: Previous studies showed that the effect of antivirals for COVID-19 was promising but varied across patient population, and was modest among severe cases. Chinese Medicine (CM) was extensively used and reported effective in China, awaiting further evidence support. We aimed to evaluate the real-world effectiveness of add-on semi-individualized.Methods: A retrospective total sampling cohort of 1788 adult confirmed COVID-19 patients were recruited from all 2235 consecutive records retrieved from 5 hospitals in Wuhan during15 January to 13 March 2020. Consultation notes, laboratory/imaging investigations, pharmacy and prognosis records were linked by an electronic medical record system and verified by at least 2 researchers independently. The mortality of add-on semi-individualized CM users and non-users was compared by weighted hazard ratios of multivariable Cox regression and by propensity score matching. Change of biomarkers was compared between groups and the frequency of CMs used was analysed. Subgroup analysis was performed to stratify disease severity and dose of CM exposure. Sensitivity analyses were conducted to test the robustness.Findings: The crude mortality was 3.8% in the semi-individualized CM user group and 17.0% among the non-users. Add-on CM was associated with a significant mortality reduction of 58% (HR=0.42, 95%CI: 0.23 to 0.77, p=0.005) and 66% (HR=0.34, 95%CI: 0.15 to 0.76, p=0.009) among all and severe/critical COVID-19 cases with dose-dependent response, after inversely weighted with propensity score calculated by age, gender, history of hypertension, diabetes, coronary artery disease and disease severity. The result was robust in various stratified, weighted, matched, adjusted and sensitivity analyses. Severe/critical patients received add-on CM had a trend of stabilized D-dimer level after 3-7 days of admission compared to baseline.Interpretation: Add-on semi-individualized CM was associated with reduced mortality demonstrating dose-dependent response, especially among severe/critical COVID-19 patients. Chinese medicine could be considered as an add-on regimen for trial use.Funding Statement: This work is partially supported by the National Key Research and Development Program (2017YFC1703506 and 2020YFC0841600). Declaration of Interests: No financial relationships with any organisations that might have an interest in the submitted work in the previous three years;no other relationships or activities that could appear to have influenced the submitted work.Ethics Approval Statement: This study was approved by the ethics review board of Hubei Provincial Hospital of Traditional Chinese Medicine (HBZY2020-C01-01). Written consent was waived due to the retrospective nature.

5.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-309633

ABSTRACT

Background: Public health measures against COVID-19 may influence other disease epidemics. Many countries have reported significant reductions in influenza activity in 2020–2021, but the prevalence of other respiratory pathogens during the COVID-19 pandemic has rarely been reported, especially in China.Methods: Data from the Respiratory Pathogen Surveillance System in Beijing were analyzed to compare pathogen infection rates before the COVID-19 (from 1 February 2015 to 31 January 2020) and during the COVID-19 (from 1 February 2020 to 31 January 2021).Findings: Among 41630 acute respiratory tract infections 13630 had at least one pathogen positive result, which decreased from 32·16% (95% CI 31·69%, 32·64%) before the COVID-19 to 10·97% (95% CI 10·03%, 11·96%) during the COVID-19, representing a 65·90% decrease (P<0·001). The positivity rate fluctuated with the strictness of public health measures. Before the COVID-19 epidemic, the top five of the pathogenic spectrums were IFV (26·27%), MP (19·30%), HPIV (11·80%), HRV (9·38%), and EV (8·38%), while during the COVID-19, the top five were seasonal HCoV (21·10%), HRV (18·99%), HPIV (14·98%), IFV (13·08%), and RSV (10.76%).Interpretation: The prevalence of respiratory pathogens decreased significantly during the COVID-19, closely relating to public health measures against COVID-19;these measures can serve as useful strategies for the prevention and control of other respiratory tract infections.Funding Statement: The National Major Science and Technology Project for Control and Prevention of Major Infectious Diseases in China (2017ZX10103004).Declaration of Interests: FH received funds from the National Major Science and Technology Project for Control and Prevention of Major Infectious Diseases in China (2017ZX10103004). All other authors declare no competing interests.Ethics Approval Statement: Ethics approval for the protocol of this study was obtained from the Ethics Committee of the BJCDC. Written informed consent was obtained.

6.
Biomed Environ Sci ; 34(12): 976-983, 2021 Dec 20.
Article in English | MEDLINE | ID: covidwho-1606117

ABSTRACT

OBJECTIVE: The coronavirus disease 2019 (COVID-19) pandemic continues to present a major challenge to public health. Vaccine development requires an understanding of the kinetics of neutralizing antibody (NAb) responses to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). METHODS: In total, 605 serum samples from 125 COVID-19 patients (from January 1 to March 14, 2020) varying in age, sex, severity of symptoms, and presence of underlying diseases were collected, and antibody titers were measured using a micro-neutralization assay with wild-type SARS-CoV-2. RESULTS: NAbs were detectable approximately 10 days post-onset (dpo) of symptoms and peaked at approximately 20 dpo. The NAb levels were slightly higher in young males and severe cases, while no significant difference was observed for the other classifications. In follow-up cases, the NAb titer had increased or stabilized in 18 cases, whereas it had decreased in 26 cases, and in one case NAbs were undetectable at the end of our observation. Although a decreasing trend in NAb titer was observed in many cases, the NAb level was generally still protective. CONCLUSION: We demonstrated that NAb levels vary among all categories of COVID-19 patients. Long-term studies are needed to determine the longevity and protective efficiency of NAbs induced by SARS-CoV-2.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/immunology , Adult , Aged , Aged, 80 and over , Female , Humans , Kinetics , Male , Middle Aged , Neutralization Tests , SARS-CoV-2
7.
Zhonghua Liu Xing Bing Xue Za Zhi ; 42(3): 427-432, 2021 Mar 10.
Article in Chinese | MEDLINE | ID: covidwho-1534262

ABSTRACT

Objective: To investigate the clusters of COVID-19 associated with a market (market Y) in Haidian District, Beijing, and analyze the chain of transmission and provide reference for effective prevention and control of COVID-19. Methods: The investigation of field epidemiology and cluster epidemic was used to describe the distributions of all COVID-19 cases. The time sequence diagram of the cases, disease onset was drawn and transmission chains were analyzed. Real-time RT-PCR assay was conducted for SARS-CoV-2 nucleic acid test by using the respiratory samples of the cases. Results: The COVID-19 epidemic, originated from a wholesale farm produce market (market X) in Fengtai District, Beijing, was introduced by a marketer in the market Y who had exposed to market X, causing 8 clusters of 20 confirmed cases of COVID-19 and one asymptomatic case, including 8 men and 13 women, in market Y, surrounding communities, food plaza, companies,families and other places. The incidence peaked during June 10-14, 2020; the median age of the cases was 45 years, ranging from 5 years to 87 years. The initial symptoms of the cases included fever (10/20) and pharynx discomfort (7/20). The median of incubation period was 5 days (IQR:3-8). The median of serial interval between primary case and secondary cases was 5 days with a secondary attack rate of 3.7%(20/538), and the secondary attack rate in household close-contacts was 14.0% (7/50). Conclusions: The clusters of COVID-19 associated with market Y were caused by several modes of transmission, including human-to-human, contaminated material-to-human, etc. The combined public-health response measures were effective to control the COVID-19 epidemic in Haidian district of Beijing.


Subject(s)
COVID-19 , Epidemics , Beijing/epidemiology , Female , Humans , Incidence , Male , Middle Aged , SARS-CoV-2
9.
Biomed Res Int ; 2021: 6967166, 2021.
Article in English | MEDLINE | ID: covidwho-1476881

ABSTRACT

Health big data has already been the most important big data for its serious privacy disclosure concerns and huge potential value of secondary use. Measurements must be taken to balance and compromise both the two serious challenges. One holistic solution or strategy is regarded as the preferred direction, by which the risk of reidentification from records should be kept as low as possible and data be shared with the principle of minimum necessary. In this article, we present a comprehensive review about privacy protection of health data from four aspects: health data, related regulations, three strategies for data sharing, and three types of methods with progressive levels. Finally, we summarize this review and identify future research directions.


Subject(s)
Confidentiality , Health Records, Personal , Privacy , Consumer Health Information , Genomics , Health Insurance Portability and Accountability Act , Humans , Information Dissemination , Models, Theoretical , United States
10.
Ann Transl Med ; 9(15): 1231, 2021 Aug.
Article in English | MEDLINE | ID: covidwho-1362796

ABSTRACT

BACKGROUND: The aim of this study was to evaluate long-term longitudinal changes in chest computed tomography (CT) findings in coronavirus disease 2019 (COVID-19) survivors and their correlations with dyspnea after discharge. METHODS: A total of 337 COVID-19 survivors who underwent CT scan during hospitalization and between 102 and 361 days after onset were retrospectively included. Subjective CT findings, lesion volume, therapeutic measures and laboratory parameters were collected. The severity of the survivors' dyspnea was determined by follow-up questionnaire. The evolution of the CT findings from the peak period to discharge and throughout follow-up and the abilities of CT findings and clinical parameters to predict survival with and without dyspnea were analyzed. RESULTS: Ninety-one COVID-19 survivors still had dyspnea at follow-up. The age, comorbidity score, duration of hospital stays, receipt of hormone administration, receipt of immunoglobulin injections, intensive care unit (ICU) admission, receipt of mechanical ventilation, laboratory parameters, clinical classifications and parameters associated with lesion volume of the survivors with dyspnea were significantly different from those of survivors without dyspnea. Among the clinical parameters and CT parameters used to identify dyspnea, parameters associated with lesion volume showed the largest area under the curve (AUC) values, with lesion volume at discharge showing the largest AUC (0.820). Lesion volume decreased gradually from the peak period to discharge and through follow-up, with a notable decrease observed after discharge. Absorption of lesions continued 6 months after discharge. CONCLUSIONS: Among the clinical parameters and subjective CT findings, CT findings associated with lesion volume were the best predictors of post-discharge dyspnea in COVID-19 survivors.

11.
Journal of Physics: Conference Series ; 1948(1), 2021.
Article in English | ProQuest Central | ID: covidwho-1286526

ABSTRACT

In weakly supervised learning, it is difficult for us to utilize pairwise constraints information in feature selection. In order to solve the problem, we propose Pairwise constraints cross entropy fuzzy clustering algorithm based on manifold learning and feature selection (FCPC-LEFS). There are four phases in our approach: 1) Generate pseudo label;2) Dimension reduction by Laplacian Eigenmaps;3) Feature increment and selection;4) Cross-Entropy semi-Supervised Clustering Based on Pairwise Constraints. We apply our approach to three UCI datasets and a COVID19-CT image dataset. Experiments show that our manifold learning and feature selection method are able to increase improve the clustering performance.

12.
Turk J Med Sci ; 2021 May 23.
Article in English | MEDLINE | ID: covidwho-1239041

ABSTRACT

BACKGROUND: The outbreak of coronavirus disease 2019 (COVID-19) has been an almost global pandemic with significant public health impacts. The increasing prevalence of malignancy has become a leading cause of human mortality. However, conflicting findings have been published on the association between malignancy and COVID-19 severity. This study aims to assess the pooled proportion of malignancy amongst 2019-nCov patients and to investigate the association between malignancy and COVID-19 severity. METHODS: Correlative studies were identi?ed by systematically searching electronic databases (PubMed, Web of Sciences and Embase) up to September 2, 2020. All data analyses were carried out using Stata 15.0. RESULTS: Twenty-nine studies consisting of 9475 confirmed COVID-19 patients (median age 54.4 years [IQR 49-62], 54.0% men) were included. The overall proportion of malignancy was 2.5% (95% CI 1.6%-3.4%). The proportion of malignancy was higher in patients with severe/critical 2019-nCoV than those in non-severe/non-critical group (3.9% [95% CI 2.0-6.3] vs 1.4% [95% CI 0.8-2.2]). Furthermore, pre-existing malignancy was associated with more than twofold higher risk of severe/critical patients with COVID-19 (OR 2.25, 95% CI 1.65-3.06 I2 = 0.0%). CONCLUSION: Malignancy was associated with up to 2.3-fold higher risk of severe/critical COVID-19 and may serve as a clinical predictor for adverse outcomes.

13.
Signal Transduct Target Ther ; 6(1): 195, 2021 05 17.
Article in English | MEDLINE | ID: covidwho-1232065

ABSTRACT

B cell response plays a critical role against SARS-CoV-2 infection. However, little is known about the diversity and frequency of the paired SARS-CoV-2 antigen-specific BCR repertoire after SARS-CoV-2 infection. Here, we performed single-cell RNA sequencing and VDJ sequencing using the memory and plasma B cells isolated from five convalescent COVID-19 patients, and analyzed the spectrum and transcriptional heterogeneity of antibody immune responses. Via linking BCR to antigen specificity through sequencing (LIBRA-seq), we identified a distinct activated memory B cell subgroup (CD11chigh CD95high) had a higher proportion of SARS-CoV-2 antigen-labeled cells compared with memory B cells. Our results revealed the diversity of paired BCR repertoire and the non-stochastic pairing of SARS-CoV-2 antigen-specific immunoglobulin heavy and light chains after SARS-CoV-2 infection. The public antibody clonotypes were shared by distinct convalescent individuals. Moreover, several antibodies isolated by LIBRA-seq showed high binding affinity against SARS-CoV-2 receptor-binding domain (RBD) or nucleoprotein (NP) via ELISA assay. Two RBD-reactive antibodies C14646P3S and C2767P3S isolated by LIBRA-seq exhibited high neutralizing activities against both pseudotyped and authentic SARS-CoV-2 viruses in vitro. Our study provides fundamental insights into B cell response following SARS-CoV-2 infection at the single-cell level.


Subject(s)
B-Lymphocytes/immunology , COVID-19/immunology , Convalescence , Immunologic Memory , RNA-Seq , SARS-CoV-2/immunology , Animals , B-Lymphocytes/pathology , COVID-19/genetics , COVID-19/pathology , Cell Line, Tumor , Cell Separation , Chlorocebus aethiops , HEK293 Cells , Humans , SARS-CoV-2/genetics , Vero Cells
14.
Sci Rep ; 11(1): 8529, 2021 04 20.
Article in English | MEDLINE | ID: covidwho-1195628

ABSTRACT

This study aimed to determine the levels of health-related behaviours (physical activity, screen exposure and sleep status) among Chinese students from primary, secondary and high schools during the pandemic of COVID-19, as well as their changes compared with their status before the pandemic. A cross-sectional online survey of 10,933 students was conducted among 10 schools in Guangzhou, China, between 8th and 15th March, 2020. After getting the informed consent from student's caregivers, an online questionnaire was designed and used to obtain time spending on health-related behaviours during the pandemic of COVID-19, as well as the changes compared with 3 months before the pandemic, which was completed by students themselves or their caregivers. Students were stratified by regions (urban, suburban, exurban), gender (boys and girls), and grades (lower grades of primary school, higher grades of primary schools, secondary schools and high schools). Data were expressed as number and percentages and Chi-square test was used to analyse difference between groups. Overall, the response rate of questionnaire was 95.3% (10,416/10,933). The median age of included students was 13.0 (10.0, 16.0) years and 50.1% (n = 5,219) were boys. 41.4%, 53.6% and 53.7% of total students reported less than 15 min per day in light, moderate and vigorous activities and 58.7% (n = 6,113) reported decreased participation in physical activity compared with the time before pandemic. Over 5 h of screen time spending on online study was reported by 44.6% (n = 4,649) of respondents, particular among high school students (81.0%). 76.9% of students reported increased screen time compared with the time before pandemic. Inadequate sleep was identified among 38.5% of students and the proportion was highest in high school students (56.9%). Our study indicated that, during the COVID-19 pandemic, the school closure exerted tremendous negative effects on school-aged children's health habits, including less physical activity, longer screen exposure and irregular sleeping pattern.


Subject(s)
COVID-19/epidemiology , Exercise/psychology , Screen Time , Sleep Deprivation/epidemiology , Students/psychology , Adolescent , COVID-19/psychology , Child , China/epidemiology , Cross-Sectional Studies , Female , Humans , Male , Pandemics , Surveys and Questionnaires
15.
Am J Chin Med ; 49(3): 543-575, 2021.
Article in English | MEDLINE | ID: covidwho-1119998

ABSTRACT

Chinese medicine (CM) was extensively used to treat COVID-19 in China. We aimed to evaluate the real-world effectiveness of add-on semi-individualized CM during the outbreak. A retrospective cohort of 1788 adult confirmed COVID-19 patients were recruited from 2235 consecutive linked records retrieved from five hospitals in Wuhan during 15 January to 13 March 2020. The mortality of add-on semi-individualized CM users and non-users was compared by inverse probability weighted hazard ratio (HR) and by propensity score matching. Change of biomarkers was compared between groups, and the frequency of CMs used was analyzed. Subgroup analysis was performed to stratify disease severity and dose of CM exposure. The crude mortality was 3.8% in the semi-individualized CM user group and 17.0% among the non-users. Add-on CM was associated with a mortality reduction of 58% (HR = 0.42, 95% CI: 0.23 to 0.77, [Formula: see text] = 0.005) among all COVID-19 cases and 66% (HR = 0.34, 95% CI: 0.15 to 0.76, [Formula: see text] = 0.009) among severe/critical COVID-19 cases demonstrating dose-dependent response, after inversely weighted with propensity score. The result was robust in various stratified, weighted, matched, adjusted and sensitivity analyses. Severe/critical patients that received add-on CM had a trend of stabilized D-dimer level after 3-7 days of admission when compared to baseline. Immunomodulating and anti-asthmatic CMs were most used. Add-on semi-individualized CM was associated with significantly reduced mortality, especially among severe/critical cases. Chinese medicine could be considered as an add-on regimen for trial use.


Subject(s)
COVID-19/prevention & control , Drugs, Chinese Herbal/therapeutic use , Hospitalization/statistics & numerical data , Medicine, Chinese Traditional/methods , Registries/statistics & numerical data , SARS-CoV-2/drug effects , Adult , Aged , Aged, 80 and over , COVID-19/epidemiology , COVID-19/virology , China/epidemiology , Drugs, Chinese Herbal/classification , Epidemics , Female , Humans , Male , Middle Aged , Retrospective Studies , SARS-CoV-2/isolation & purification , SARS-CoV-2/physiology
16.
Disease Surveillance ; 35(7):602-607, 2020.
Article in Chinese | GIM | ID: covidwho-826659

ABSTRACT

Objective: To analyze the epidemiological characteristics of the confirmed coronavirus diseases 2019 (COVID-19) cases reported in Haidian district of Beijing and provide basic data for the effective prevention and control of COVID-19.

18.
Korean J Radiol ; 21(8): 998-1006, 2020 08.
Article in English | MEDLINE | ID: covidwho-723534

ABSTRACT

OBJECTIVE: To compare the accuracies of quantitative computed tomography (CT) parameters and semiquantitative visual score in evaluating clinical classification of severity of coronavirus disease (COVID-19). MATERIALS AND METHODS: We retrospectively enrolled 187 patients with COVID-19 treated at Tongji Hospital of Tongji Medical College from February 15, 2020, to February 29, 2020. Demographic data, imaging characteristics, and clinical data were collected, and based on the clinical classification of severity, patients were divided into groups 1 (mild) and 2 (severe/critical). A semiquantitative visual score was used to estimate the lesion extent. A three-dimensional slicer was used to precisely quantify the volume and CT value of the lung and lesions. Correlation coefficients of the quantitative CT parameters, semiquantitative visual score, and clinical classification were calculated using Spearman's correlation. A receiver operating characteristic curve was used to compare the accuracies of quantitative and semi-quantitative methods. RESULTS: There were 59 patients in group 1 and 128 patients in group 2. The mean age and sex distribution of the two groups were not significantly different. The lesions were primarily located in the subpleural area. Compared to group 1, group 2 had larger values for all volume-dependent parameters (p < 0.001). The percentage of lesions had the strongest correlation with disease severity with a correlation coefficient of 0.495. In comparison, the correlation coefficient of semiquantitative score was 0.349. To classify the severity of COVID-19, area under the curve of the percentage of lesions was the highest (0.807; 95% confidence interval, 0.744-0.861: p < 0.001) and that of the quantitative CT parameters was significantly higher than that of the semiquantitative visual score (p = 0.001). CONCLUSION: The classification accuracy of quantitative CT parameters was significantly superior to that of semiquantitative visual score in terms of evaluating the severity of COVID-19.


Subject(s)
Betacoronavirus , Coronavirus Infections/diagnostic imaging , Pneumonia, Viral/diagnostic imaging , Adult , Aged , COVID-19 , Female , Humans , Lung/diagnostic imaging , Male , Middle Aged , Pandemics , ROC Curve , Retrospective Studies , SARS-CoV-2 , Severity of Illness Index , Tomography, X-Ray Computed/methods
19.
Lancet Infect Dis ; 20(8): 920-928, 2020 08.
Article in English | MEDLINE | ID: covidwho-276988

ABSTRACT

BACKGROUND: In December, 2019, the newly identified severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, China, causing COVID-19, a respiratory disease presenting with fever, cough, and often pneumonia. WHO has set the strategic objective to interrupt spread of SARS-CoV-2 worldwide. An outbreak in Bavaria, Germany, starting at the end of January, 2020, provided the opportunity to study transmission events, incubation period, and secondary attack rates. METHODS: A case was defined as a person with SARS-CoV-2 infection confirmed by RT-PCR. Case interviews were done to describe timing of onset and nature of symptoms and to identify and classify contacts as high risk (had cumulative face-to-face contact with a confirmed case for ≥15 min, direct contact with secretions or body fluids of a patient with confirmed COVID-19, or, in the case of health-care workers, had worked within 2 m of a patient with confirmed COVID-19 without personal protective equipment) or low risk (all other contacts). High-risk contacts were ordered to stay at home in quarantine for 14 days and were actively followed up and monitored for symptoms, and low-risk contacts were tested upon self-reporting of symptoms. We defined fever and cough as specific symptoms, and defined a prodromal phase as the presence of non-specific symptoms for at least 1 day before the onset of specific symptoms. Whole genome sequencing was used to confirm epidemiological links and clarify transmission events where contact histories were ambiguous; integration with epidemiological data enabled precise reconstruction of exposure events and incubation periods. Secondary attack rates were calculated as the number of cases divided by the number of contacts, using Fisher's exact test for the 95% CIs. FINDINGS: Patient 0 was a Chinese resident who visited Germany for professional reasons. 16 subsequent cases, often with mild and non-specific symptoms, emerged in four transmission generations. Signature mutations in the viral genome occurred upon foundation of generation 2, as well as in one case pertaining to generation 4. The median incubation period was 4·0 days (IQR 2·3-4·3) and the median serial interval was 4·0 days (3·0-5·0). Transmission events were likely to have occurred presymptomatically for one case (possibly five more), at the day of symptom onset for four cases (possibly five more), and the remainder after the day of symptom onset or unknown. One or two cases resulted from contact with a case during the prodromal phase. Secondary attack rates were 75·0% (95% CI 19·0-99·0; three of four people) among members of a household cluster in common isolation, 10·0% (1·2-32·0; two of 20) among household contacts only together until isolation of the patient, and 5·1% (2·6-8·9; 11 of 217) among non-household, high-risk contacts. INTERPRETATION: Although patients in our study presented with predominately mild, non-specific symptoms, infectiousness before or on the day of symptom onset was substantial. Additionally, the incubation period was often very short and false-negative tests occurred. These results suggest that although the outbreak was controlled, successful long-term and global containment of COVID-19 could be difficult to achieve. FUNDING: All authors are employed and all expenses covered by governmental, federal state, or other publicly funded institutions.


Subject(s)
Betacoronavirus/isolation & purification , Communicable Diseases, Imported/transmission , Coronavirus Infections/transmission , Disease Outbreaks , Disease Transmission, Infectious , Pneumonia, Viral/transmission , Travel-Related Illness , Adolescent , Adult , Betacoronavirus/classification , Betacoronavirus/genetics , COVID-19 , Child , Child, Preschool , China , Communicable Diseases, Imported/epidemiology , Communicable Diseases, Imported/pathology , Communicable Diseases, Imported/virology , Coronavirus Infections/epidemiology , Germany/epidemiology , Humans , Interviews as Topic , Middle Aged , Mutation , Pandemics , Pneumonia, Viral/epidemiology , RNA, Viral/genetics , Reverse Transcriptase Polymerase Chain Reaction , Risk Assessment , SARS-CoV-2 , Travel , Young Adult
SELECTION OF CITATIONS
SEARCH DETAIL