ABSTRACT
Background Respiratory virus infection is an important trigger of acute exacerbation of chronic obstructive pulmonary disease（AECOPD）. China has adopted a series of containment measures assisting to curb COVID-19 transmission since the outbreak of the pandemic. Several studies showed a decrease in hospitalizations for AECOPD during the COVID-19 pandemic. However，there has been a relative lack of studies investigating the effects of preventive measures on the frequency and severity of exacerbations. Objective To explore the impact of the COVID-19 pandemic on the frequency of AECOPD with or without medical attention. Methods The subjects were from a prospective COPD cohort study conducted in the First Affiliated Hospital of Guangzhou Medical University，which began recruiting patients in early 2016，with visits every 3 months to collect demographic and clinical data，including those who were followed up during June to August 2017（group 1），June to August 2018（group 2），June to August 2019 （group 3），and June to August 2020（group 4）. Basic clinical data （including the frequency of AECOPD，sex，age，symptom score and so on） were collected from group 1 from October 2016 to May 2017，group 2 from October 2017 to May 2018，group 3 from October 2018 to May 2019，and group 4 from October 2019 to May 2020（during which the periods from October 2019 to January 2020，and from February to May 2020 were defined as preCOVID-19 period，and post-COVID-19 period，respectively）. The frequency of AECOPD during October to May next year in group 4 was compared with that of the other three groups. The changes in the frequency of AECOPD between pre- and postCOVID-19 periods were analyzed. Results There were 162 patients in group 1，157 in group 2，167 in group 3，and 159 in group 4. Group 1 had a higher frequency of AECOPD in February to May than in October to January next year（P=0.013），so did group 2（P=0.016）. In contrast，group 4 had a higher frequency of AECOPD in October to January next year than in February to May（P=0.001）. The frequency of AECOPD during October to December in group 4 was similar to that of the other three groups（P>0.05）. But the frequency of AECOPD from February to April in group 4 was lower than that in groups 1-3 （P<0.05）. There was no significant difference in the monthly frequency of AECOPD without medical attention in group 4 compared with that of groups 1-3（P>0.05）. The frequency of AECOPD with medical attention from October to December in group 4 was similar to that of groups 1-3（P>0.05）. but it from February to April in group 4 was lower than that in groups 1-3（P<0.05）. Conclusion Prevention and control measures targeting COVID-19 may be contributive to reducing the frequency of AECOPD. It is suggested that COPD patients should reduce gathering activities，maintain social distance，wear masks when going out，and wash hands frequently even after the COVID-19. © 2023 Chinese General Practice. All rights reserved.
ABSTRACT
Background Respiratory virus infection is an important trigger of acute exacerbation of chronic obstructive pulmonary disease（AECOPD）. China has adopted a series of containment measures assisting to curb COVID-19 transmission since the outbreak of the pandemic. Several studies showed a decrease in hospitalizations for AECOPD during the COVID-19 pandemic. However，there has been a relative lack of studies investigating the effects of preventive measures on the frequency and severity of exacerbations. Objective To explore the impact of the COVID-19 pandemic on the frequency of AECOPD with or without medical attention. Methods The subjects were from a prospective COPD cohort study conducted in the First Affiliated Hospital of Guangzhou Medical University，which began recruiting patients in early 2016，with visits every 3 months to collect demographic and clinical data，including those who were followed up during June to August 2017（group 1），June to August 2018（group 2），June to August 2019 （group 3），and June to August 2020（group 4）. Basic clinical data （including the frequency of AECOPD，sex，age，symptom score and so on） were collected from group 1 from October 2016 to May 2017，group 2 from October 2017 to May 2018，group 3 from October 2018 to May 2019，and group 4 from October 2019 to May 2020（during which the periods from October 2019 to January 2020，and from February to May 2020 were defined as preCOVID-19 period，and post-COVID-19 period，respectively）. The frequency of AECOPD during October to May next year in group 4 was compared with that of the other three groups. The changes in the frequency of AECOPD between pre- and postCOVID-19 periods were analyzed. Results There were 162 patients in group 1，157 in group 2，167 in group 3，and 159 in group 4. Group 1 had a higher frequency of AECOPD in February to May than in October to January next year（P=0.013），so did group 2（P=0.016）. In contrast，group 4 had a higher frequency of AECOPD in October to January next year than in February to May（P=0.001）. The frequency of AECOPD during October to December in group 4 was similar to that of the other three groups（P>0.05）. But the frequency of AECOPD from February to April in group 4 was lower than that in groups 1-3 （P<0.05）. There was no significant difference in the monthly frequency of AECOPD without medical attention in group 4 compared with that of groups 1-3（P>0.05）. The frequency of AECOPD with medical attention from October to December in group 4 was similar to that of groups 1-3（P>0.05）. but it from February to April in group 4 was lower than that in groups 1-3（P<0.05）. Conclusion Prevention and control measures targeting COVID-19 may be contributive to reducing the frequency of AECOPD. It is suggested that COPD patients should reduce gathering activities，maintain social distance，wear masks when going out，and wash hands frequently even after the COVID-19. © 2023 Chinese General Practice. All rights reserved.
ABSTRACT
Objective: To analyze the clinical value of serum 2019 novel coronavirus (2019-nCoV) immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies in the diagnosis of COVID-19. Methods: A total of 116 patients diagnosed with NCP in the First Affiliated Hospital of Hunan University of Chinese Medicine and the First Affiliated Hospital of Xiamen University were enrolled from January to February 2020 as the disease group. A total of 134 cases, including 84 non-NCP inpatients and 50 healthy individuals served as the control group. Serum samples from all subjects were collected. A fully-automated chemiluminescence immunoassay analyzer was used to detect the concentration of 2019-nCoV IgM and IgG antibodies in serum. The sensitivity and specificity of the 2019-nCoV IgM and IgG antibody single test and combined detection were compared using the χ2 test. χ2 test and Wilcoxon's rank sum test were used to compare the positive rates and concentrations of IgM and IgG antibodies in NCP patients before and after their 2019-nCoV nucleic acid tests turning negative, respectively. The change trend of 2019-nCoV antibody concentration in the process of NCP patients was analyzed by Wilcoxon's rank sum test. Results: The sensitivity of 2019-nCoV IgG (90.5%, 105/116) was higher than that of 2019-nCoV IgM (75.9%, 88/116), the difference was statistically significant (χ2=8.91, P<0.05);The specificity of 2019-nCoV IgG (99.3%,133/134) was higher than that of 2019-nCoV IgM (94.0%, 126/134), the difference was statistically significant (χ2=5.63,P<0.05). The sensitivity (89.7%,87/97) of 2019-nCoV IgM combined with IgG was higher than that of 2019-nCoV IgM, the difference was statistically significant (χ2=6.89,P<0.05). The specificity (100%, 125/125) of 2019-nCoV IgM combined with IgG was higher than that of 2019-nCoV IgM, the difference was statistically significant (χ2=7.70, P<0.05). After 2019-nCoV nucleic acid test converted to negative, the positive rate (9/17) and concentration [13.0 (4.9, 24.7) AU/ml] of serum 2019-nCoV IgM antibody were significantly lower than those when the nucleic acid test was positive, positive rate (15/17) and concentration [29.5 (14.0, 61.3) AU/ml], respectively (χ2=5.10, Z=-3.195, both P<0.05). In the course of NCP, patients' serum samples were collected from the first day of diagnosis to every three days, three times in total. The first 2019-nCoV IgM and IgG antibody concentrations [19.4 (12.4, 63.7) AU/ml, 105.8 (74.8, 126.1) AU/ml, respectively] were significantly higher than the second concentrations [15.8 (7.1, 40.3)AU/ml, 80.5 (66.7, 105.9) AU/ml], Z were-2.897,-3.179, both P<0.05. Conclusions: 2019-nCoV IgG antibody has a good application value in the diagnosis of NCP. The concentration of 2019-nCoV IgM antibody has a certain correlation with the detection of 2019-nCoV nucleic acid. The combination of 2019-nCoV IgM and IgG antibodies with 2019-nCoV nucleic acid test may be the best laboratory index for the diagnosis of NCP at present.
ABSTRACT
Objective: China adopted an unprecedented province-scale quarantine since January 23rd 2020, after the novel coronavirus (COVID-19) broke out in Wuhan in December 2019. Responding to the challenge of limited testing capacity, large-scale (>20 000 tests per day) standardized and fully-automated laboratory (Huo-Yan) was built as an ad-hoc measure. There is so far no empirical data or mathematical model to reveal the impact of the testing capacity improvement since quarantine. Methods: Based on the suspected case data released by the Health Commission of Hubei Province and the daily testing data of Huo-Yan Laboratory, the impact of detection capabilities on the realization of "clearing" and "clearing the day" of supected cases was simulated by establishing a novel non-linear and competitive compartments differential model. Results: Without the establishment of Huo-Yan, the suspected cases would increase by 47% to 33 700, the corresponding cost of quarantine would be doubled, the turning point of the increment of suspected cases and the achievement of "daily settlement" (all newly discovered suspected cases are diagnosed according to the nucleic acid testing result) would be delayed for a whole week and 11 days. If the Huo-Yan Laboratory could ran at its full capacity, the number of suspected cases could start to decrease at least a week earlier, the peak of suspected cases would be reduced by at least 44%, and the quarantine cost could be reduced by more than 72%. Ideally, if a daily testing capacity of 10 500 tests was achieved immediately after the Hubei lockdown, "daily settlement" for all suspected cases could be achieved. Conclusions: Large-scale, standardized clinical testing platform, with nucleic acid testing, high-throughput sequencing, and immunoprotein assessment capabilities, need to be implemented simultaneously in order to maximize the effect of quarantine and minimize the duration and cost of the quarantine. Such infrastructure, for both common times and emergencies, is of great significance for the early prevention and control of infectious diseases.