ABSTRACT
Objective To describe the spatial distribution of COVID-19 cases in Shaanxi Province and further explore its relevant factors, so as to provide evidence for the prevention and control of COVID-19 in Shaanxi Province. Methods The information of confirmed COVID-19 cases and relevant socioeconomic data in Shaanxi Province were collected. The temporal and spatial distribution characteristics of confirmed cases, and the correlation between the incidence of COVID-19 and socioeconomic factors in the population were analyzed by using a generalized linear model. Results Four cases were first reported in Shaanxi on 23 January 2020, with the highest number of new confirmed cases reaching 23 on 4 February and no new cases after 19 February. The imported cases appeared earlier and reached the new peak than the local cases, and entered the zero stage earlier than the local cases. The spatial distribution showed that Xi′ an (120 cases) had the largest number of confirmed cases, accounting for 48.98% of the total cases, and the districts with more confirmed cases were in Lianhu, Yanta, Xincheng and Weiyang. Socioeconomic factors which significantly associated with the number of confirmed cases in each district and country were education expenditure (IRR=0.287, 95% CI: 0.134-0.612), GDP per capita (IRR=1.143, 95% CI: 1.049-1.245) and the distance from Wuhan (IRR=0.995, 95% CI: 0.992-0.998). Conclusion Measures should be taken in key areas and population at the early stage of the epidemic to control the spread of the epidemic as soon as possible. © 2021, Publication Centre of Anhui Medical University. All rights reserved.
ABSTRACT
Objective: To understand the incidence trend and epidemiological characteristics of COVID-19 in Shaanxi province. Methods: The incidence data of COVID-19 reported in Shaanxi as of 22 February, 2020 were collected for an epidemiological descriptive analysis. Results: A total of 245 confirmed cases of COVID-19 were reported in Shaanxi. Most cases were mild (87.76%). As time passed, the areas where confirmed cases were reported continued to increase. The case number in Xi'an was highest, accounting for nearly half of the total reported cases in the province. The epidemic pattern in Shaanxi had gradually shifted from imported case pattern to local case pattern, and the transmission of local cases was mainly based on family cluster transmission. The confirmed cases from different sources had caused the secondary transmission in Shaanxi. After February 7, the number of reported cases began to fluctuate and decrease stably, indicating a decrease-to-zero period. Conclusions: At present, the overall epidemic of COVID-19 in Shaanxi has gradually been mitigated. However, considering the approaching of return to work and study and the increasing of imported cases from other countries, the prevention and control of COVIS-19 in Shaanxi will face new challenges.
ABSTRACT
Editor office's response for Ahead of Print article withdrawn The article "Potential false-positive rate among the 'asymptomatic infected individuals' in close contacts of COVID-19 patients" was under strong discussion after pre-published. Questions from the readers mainly focused on the article's results and conclusions were depended on theoretical deduction, but not the field epidemiology data and further researches were needed to prove the current theory. Based on previous discussions, the article was decided to be offline by the editorial board from the pre-publish lists. Objective: As the prevention and control of COVID-19continues to advance, the active nucleic acid test screening in the close contacts of the patients has been carrying out in many parts of China. However, the false-positive rate of positive results in the screening has not been reported up to now. But to clearify the false-positive rate during screening is important in COVID-19 control and prevention. Methods: Point values and reasonable ranges of the indicators which impact the false-positive rate of positive results were estimated based on the information available to us at present. The false-positive rate of positive results in the active screening was deduced, and univariate and multivariate-probabilistic sensitivity analyses were performed to understand the robustness of the findings. Results: When the infection rate of the close contacts and the sensitivity and specificity of reported results were taken as the point estimates, the positive predictive value of the active screening was only 19.67%, in contrast, the false-positive rate of positive results was 80.33%. The multivariate-probabilistic sensitivity analysis results supported the base-case findings, with a 75% probability for the false-positive rate of positive results over 47%. Conclusions: In the close contacts of COVID-19 patients, nearly half or even more of the 'asymptomatic infected individuals' reported in the active nucleic acid test screening might be false positives.