ABSTRACT
Background We aim to investigate the profile of acute antibody response in COVID-19 patients, and provide proposals for the usage of antibody test in clinical practice. Methods A multi-center cross-section study (285 patients) and a single-center follow-up study (63 patients) were performed to investigate the feature of acute antibody response to SARS-CoV-2. A cohort of 52 COVID-19 suspects and 64 close contacts were enrolled to evaluate the potentiality of the antibody test. Results The positive rate for IgG reached 100% around 20 days after symptoms onset. The median day of serocon-version for both lgG and IgM was 13 days after symptoms onset. Seroconversion of IgM occurred at the same time, or earlier, or later than that of IgG. IgG levels in 100% patients (19/19) entered a platform within 6 days after seroconversion. The criteria of IgG seroconversion and [≥] 4-fold increase in the IgG titers in sequential samples together diagnosed 82.9% (34/41) of the patients. Antibody test aided to confirm 4 patients with COVID-19 from 52 suspects who failed to be confirmed by RT-PCR and 7 patients from 148 close contacts with negative RT-PCR. Conclusion IgM and IgG should be detected simultaneously at the early phase of infection. The serological diagnosis criterion of seroconversion or [≥] 4-fold increase in the IgG titer is suitable for a majority of COVID-19 patients. Serologic test is helpful for the diagnosis of SARS-CoV-2 infection in suspects and close contacts.
Subject(s)
COVID-19ABSTRACT
Background: Adolescents and young adults might play a key role in the worldwide spread of Coronavirus Disease 2019 (COVID-19), because they are more involved in overseas studying, business, working, and travelling. However, the epidemiological and clinical characteristics of them are still unknown. Methods: We collected data of 46 confirmed COVID-19 patients aged 10 to 35 years from the study hospital. The demographics, epidemiological, and clinical data were collected. Several key epidemiological parameters, the asymptomatic cases and transmission to their family members and the clinical characteristics at admission, and during treatment were summarized. RESULTS: Of 46 confirmed patients, 14 patients (47.3%) were aged from 10 to 24 years, and 24 (52.7%) patients were male. The mean incubation period for symptomatic cases was 6.6 days (95% confidence interval (CI) 4.4 - 9.6). The median serial interval was 1.9 days (95% CI 0.4 - 6.2). Three of asymptomatic cases showed the transmission to their family members. Only 1 patient was identified as severe cases at admission. The common symptoms at admission were dry cough (34, 91.0%), and fever (29, 69.0%). Nearly 60% of the patients had showed ground-glass opacity by chest CT findings. Three patients developed acute kidney injury during treatment. Majority of patients (78.3%) were discharged by the end of the follow-up. Conclusions: The adolescent and young adult patients of COVID-19 had a long incubation period, and a short serial interval. The transmission to their family contactors occurred in asymptomatic cases. Few of the study patients have developed complications during treatment.
Subject(s)
COVID-19 , Fever , Acute Kidney InjuryABSTRACT
Objective@#To improve the diagnostic criteria of suspected cases through investigating the epidemiological and clinical manifestations of confirmed cases of new-type coronavirus infection in children.@*Methods@#We retrospective analyzed the epidemiological and clinical manifestations of 6 children with new coronavirus infection diagnosed in Chongqing Three Gorges Central Hospital from February 3, 2020 to February 15, 2020 . Compared with the diagnostic criteria of suspected cases,we summarized the problems encountered in the application of this standard in clinical work and try to put forward Suggestions for improvement.@*Results@#Among the 6 children with confirmed cases: 5 males and 1 female; 3 from Hubei Province and 3 from Wanzhou ; 6 cases of clustered onset of the family; Visiting nature: 3 cases of suspected case income, 3 cases of community or outpatient screening . Three cases with fever and / or respiratory symptoms, one of which had symptoms of diarrhea; all children's blood routine and lymphocyte counts were within the normal range; chest CT imaging except for cases No. 1 and No. 5 were in line with typical new coronavirus pneumonia signs. In addition, the remaining 3 patients had abnormal imaging but did not have the characteristics of new coronavirus pneumonia, and 1 case was normal. Comparison results:Only case 1 of all cases fully met the diagnostic criteria, and the remaining cases did not meet the diagnostic criteria of early suspected cases.@*Conclusion@#In order to improve the accuracy and practicality of the diagnosis of suspected cases in children, it is recommended to refine and standardize the diagnostic criteria of some suspected cases.
ABSTRACT
Background: To explore the cellular immunity and cytokines status of NCP patients and to predict the correlation between the cellular immunity levels, cytokines and the severity of patients. Methods: 123 NCP patients were divided into mild and severe groups. Peripheral blood was collected, lymphocyte subsets and cytokines were detected. Correlation analysis was performed on the lymphocyte subsets and cytokines, and the differences between the indexes of the two groups were analyzed. Results: 102 mild and 21 severe patients were included. Lymphocyte subsets were reduced in two groups. The proportion of CD8 + T reduction in the mild and severe group was 28.43% and 61.9%, respectively; The proportion of B cell reduction was 25.49% and 28.57%; The proportion of NK cell reduction was 34.31% and 47.62%; The detection value of IL-6 was 0 in 55.88% of the mild group, mild group has a significantly lower proportion of patients with IL-6 higher than normal than severe group; There was no significant linear correlation between the lymphocyte subsets and cytokines, while significant differences were noticed between the two groups in CD4 + T, CD8 + T, IL-6 and IL-10. Conclusions: Low levels of CD4+T and CD8+T are common in severe NCP. IL-6 and IL-10 levels were higher in severe patients. T cell subsets and cytokines can be used as one of the basis for predicting the transition from mild to severe. Large number of samples are still needed to confirm the "warning value" of CD4 + T, CD8 + T IL-6 and IL-10.