Clinical characteristics of 24 asymptomatic infections with COVID-19 screened among close contacts in Nanjing, China.
中国南京地区密切接触者中筛查的 24 例无症状感染新型冠状病毒肺炎的临床特征。
- 作者列表："Hu Z","Song C","Xu C","Jin G","Chen Y","Xu X","Ma H","Chen W","Lin Y","Zheng Y","Wang J","Hu Z","Yi Y","Shen H
:Previous studies have showed clinical characteristics of patients with the 2019 novel coronavirus disease (COVID-19) and the evidence of person-to-person transmission. Limited data are available for asymptomatic infections. This study aims to present the clinical characteristics of 24 cases with asymptomatic infection screened from close contacts and to show the transmission potential of asymptomatic COVID-19 virus carriers. Epidemiological investigations were conducted among all close contacts of COVID-19 patients (or suspected patients) in Nanjing, Jiangsu Province, China, from Jan 28 to Feb 9, 2020, both in clinic and in community. Asymptomatic carriers were laboratory-confirmed positive for the COVID-19 virus by testing the nucleic acid of the pharyngeal swab samples. Their clinical records, laboratory assessments, and chest CT scans were reviewed. As a result, none of the 24 asymptomatic cases presented any obvious symptoms while nucleic acid screening. Five cases (20.8%) developed symptoms (fever, cough, fatigue, etc.) during hospitalization. Twelve (50.0%) cases showed typical CT images of ground-glass chest and 5 (20.8%) presented stripe shadowing in the lungs. The remaining 7 (29.2%) cases showed normal CT image and had no symptoms during hospitalization. These 7 cases were younger (median age: 14.0 years; P=0.012) than the rest. None of the 24 cases developed severe COVID-19 pneumonia or died. The median communicable period, defined as the interval from the first day of positive nucleic acid tests to the first day of continuous negative tests, was 9.5 days (up to 21 days among the 24 asymptomatic cases). Through epidemiological investigation, we observed a typical asymptomatic transmission to the cohabiting family members, which even caused severe COVID-19 pneumonia. Overall, the asymptomatic carriers identified from close contacts were prone to be mildly ill during hospitalization. However, the communicable period could be up to three weeks and the communicated patients could develop severe illness. These results highlighted the importance of close contact tracing and longitudinally surveillance via virus nucleic acid tests. Further isolation recommendation and continuous nucleic acid tests may also be recommended to the patients discharged.
: 以前的研究已经显示了 2019-新型冠状病毒疾病 (新型冠状病毒肺炎) 患者的临床特征和人与人之间传播的证据。关于无症状感染的数据有限。本研究旨在呈现从密切接触者中筛选出的 24 例无症状感染病例的临床特征，并显示无症状新型冠状病毒肺炎病毒携带者的传播潜力。从 1 月 28 日至 20 20 年 2 月 9 日，对江苏省南京市新型冠状病毒肺炎例患者 (或疑似患者) 的临床和社区密切接触者进行了流行病学调查。通过检测咽拭子样本的核酸，无症状携带者实验室证实对新型冠状病毒肺炎病毒呈阳性。他们的临床记录，实验室评估和胸部ct扫描进行了审查。结果，24 例无症状病例在核酸筛查时均未出现任何明显症状。5 例 (20.8%) 在住院期间出现症状 (发热、咳嗽、乏力等)。12 例 (50.0%) 显示典型的磨玻璃胸部CT图像，5 例 (20.8%) 肺部出现条纹影。其余 7 例 (29.2%) CT图像正常，住院期间无症状。这 7 个病例比其他病例年轻 (中位年龄: 14.0 岁; P = 0.012)。24 例患者均未出现严重新型冠状病毒肺炎肺炎或死亡。传染期的中位数，定义为从核酸检测阳性的第一天到连续阴性检测的第一天的间隔，为 9.5 天 (在 24 例无症状病例中长达 21 天)。通过流行病学调查，我们观察到典型的无症状传播给同居家庭成员，甚至导致严重的新型冠状病毒肺炎肺炎。总体而言，从密切接触者中发现的无症状携带者在住院期间倾向于轻度患病。然而，传染期可能长达三周，并且被传染的患者可能发展为严重疾病。这些结果强调了通过病毒核酸检测进行密切接触者追踪和纵向监测的重要性。还可以向出院的患者推荐进一步隔离建议和连续的核酸测试。
METHODS::The antimicrobial functions of neutrophils are facilitated by a defensive armamentarium of proteins stored in granules, and by the formation of neutrophil extracellular traps (NETs). However, the toxic nature of these structures poses a threat to highly vascularized tissues, such as the lungs. Here, we identified a cell-intrinsic program that modified the neutrophil proteome in the circulation and caused the progressive loss of granule content and reduction of the NET-forming capacity. This program was driven by the receptor CXCR2 and by regulators of circadian cycles. As a consequence, lungs were protected from inflammatory injury at times of day or in mouse mutants in which granule content was low. Changes in the proteome, granule content and NET formation also occurred in human neutrophils, and correlated with the incidence and severity of respiratory distress in pneumonia patients. Our findings unveil a 'disarming' strategy of neutrophils that depletes protein stores to reduce the magnitude of inflammation.
METHODS::Pneumonia is a common respiratory infectious disease that involves the inflammation of the pulmonary parenchyma. Periodontal disease is widespread and correlated with pneumonia. However, the relationship between periodontal treatment and clinical infectious outcomes in patients with pneumonia has remained undetermined. The aim of this study was to investigate the association between periodontal treatment and the risk of pneumonia events in the Taiwanese population. A nationwide population-based cohort study was conducted using data from the Taiwanese National Health Insurance Research Database (NHIRD). A total of 49,400 chronic periodontitis patients who received periodontal treatment from 2001 to 2012 were selected. In addition, 49,400 healthy individuals without periodontal diseases were picked randomly from the general population after propensity score matching according to age, gender, monthly income, urbanization, and comorbidities. The Cox proportional hazard regression analysis was adopted to assess the hazard ratio (HR) of pneumonia between the periodontal treatment cohort and the comparison cohort. The average ages of the periodontal treatment and comparison groups were 44.25 ± 14.82 years and 44.15 ± 14.5 years, respectively. The follow up durations were 7.66 and 7.41 years for the periodontal treatment and comparison groups, respectively. We found 2504 and 1922 patients with newly diagnosed pneumonia in the comparison cohort and the periodontal treatment cohort, respectively. The Kaplan-Meier plot revealed that the cumulative incidence of pneumonia was significantly lower over the 12 year follow-up period in the periodontal treatment group (using the log-rank test, p < 0.001). In conclusion, this nationwide population-based study indicated that the patients with periodontal treatment exhibited a significantly lower risk of pneumonia than the general population.
METHODS:OBJECTIVE:To describe the treatment of community-acquired pneumonia (CAP) in children under five years in Tanzania. METHODS:Between January and December 2017, children aged 2-59 months with chest radiography-confirmed CAP were enrolled. The parents were interviewed to collect information on the patients and home-based medication. Clinical information was derived from the patient files. Nasopharyngeal swab and blood samples were collected for isolation of the causative pathogens. Swab samples were analysed by quantitative PCR whereas blood samples were tested using BacT/Alert 3D. RESULTS:Overall, 109 children with CAP were included in this analysis. Provision of care to most children was delayed (median = 4.6 days). A quarter (26.6%) were given unprescribed/leftover antibiotics at home. Only one child had positive bacterial culture. Referrals were associated with nasopharyngeal carriage of Streptococcus pneumoniae (p = 0.003) and Haemophilus influenzae (p = 0.004). Of all admitted children, more than a quarter (n = 29) did not need to be hospitalised and inappropriately received injectable instead of oral antibiotics. CONCLUSION:We found high rates of home treatment, particularly with antibiotics. Appropriate health care was delayed for most children because of home treatment. Efforts are needed at the community level to improve awareness of antimicrobial resistance.