Fangcang Shelter Hospital Research Articles

The epidemiological and clinical characteristics of COVID‐19 patients admitted to a Fangcang shelter hospital in Beijing before the change in China's prevention and control policy

AbstractIn November 2022, a large number of Omicron infections suddenly appeared in Beijing, but the epidemiological and clinical characteristics of the epidemic cases were unknown. We collected the data on COVID‐19 cases in Fangcang Hospital in Beijing from November 20, 2022, to December 8, 2022, and analyzed the epidemiological and clinical characteristics. Of the enrolled study, 85.9% were asymptomatic and 14.1% were mild. Epidemiological data showed that the transmission speed of the Omicron variant was fast and the transmission range was wide, large‐scale infections occurred in both rural and urban areas, and all age groups were susceptible to the Omicron variant. In addition, antipyretics and cough drugs were the two most used drugs, because 51.3% and 22.7% of patients had fever and cough, respectively, and 10.3% of patients took hypnotics. Furthermore, the proportion of patients with chronic diseases was low (13.9%), while the vaccination rate (71.2%) was relatively high. Based on the results, we found that most mild and asymptomatic cases did not need treatment, indicating that home isolation is correct and feasible. Although SARS‐CoV‐2 variants have characteristics such as high infectivity and immune‐escape ability, the public should not be too afraid of COVID‐19 infection; appropriate measures such as wearing masks and maintaining social distancing are sufficient to prevent reinfection.

Sleep disturbance and anxiety symptoms among asymptomatic COVID-19 carriers in Shanghai, China: the mediating role of entrapment and defeat

BackgroundThe COVID-19 pandemic increases the risk of psychological problems, especially for the infected population. Sleep disturbance and feelings of defeat and entrapment are well-documented risk factors of anxiety symptoms. Exploring the psychological mechanism of the development of anxiety symptoms is essential for effective prevention. This study aimed to examine the mediating effects of entrapment and defeat in the association between sleep disturbance and anxiety symptoms among asymptomatic COVID-19 carriers in Shanghai, China.MethodsA cross-sectional study was conducted from March to April, 2022. Participants were 1,283 asymptomatic COVID-19 carriers enrolled from the Ruijin Jiahe Fangcang Shelter Hospital, Shanghai (59.6% male; mean age = 39.6 years). Questionnaire measures of sleep disturbance, entrapment, defeat, anxiety symptoms, and background characteristics were obtained. A mediation model was constructed to test the mediating effects of entrapment and defeat in the association between sleep disturbance and anxiety symptoms.ResultsThe prevalence rates of sleep disturbance and anxiety symptoms were 34.3% and 18.8%. Sleep disturbance was positively associated with anxiety symptoms (OR [95%CI] = 5.013 [3.721–6.753]). The relationship between sleep disturbance and anxiety symptoms (total effect: Std. Estimate = 0.509) was partially mediated by entrapment (indirect effect: Std. Estimate = 0.129) and defeat (indirect effect: Std. Estimate = 0.126). The mediating effect of entrapment and defeat accounted for 50.3% of the association between sleep disturbance and anxiety symptoms.ConclusionSleep disturbance and anxiety symptoms were prevalent among asymptomatic COVID-19 carriers. Entrapment and defeat mediate the association between sleep disturbance and anxiety symptoms. More attention is needed to monitoring sleep conditions and feelings of defeat and entrapment to reduce the risk of anxiety.

The Effect of Fangcang Shelter Hospitals under Resource Constraints on the Spread of Epidemics.

Since the outbreak of the COVID-19 pandemic, Fangcang shelter hospitals have been built and operated in several cities, and have played a huge role in epidemic prevention and control. How to use medical resources effectively in order to maximize epidemic prevention and control is a big challenge that the government should address. In this paper, a two-stage infectious disease model was developed to analyze the role of Fangcang shelter hospitals in epidemic prevention and control, and examine the impact of medical resources allocation on epidemic prevention and control. Our model suggested that the Fangcang shelter hospital could effectively control the rapid spread of the epidemic, and for a very large city with a population of about 10 million and a relative shortage of medical resources, the model predicted that the final number of confirmed cases could be only 3.4% of the total population in the best case scenario. The paper further discusses the optimal solutions regarding medical resource allocation when medical resources are either limited or abundant. The results show that the optimal allocation ratio of resources between designated hospitals and Fangcang shelter hospitals varies with the amount of additional resources. When resources are relatively sufficient, the upper limit of the proportion of makeshift hospitals is about 91%, while the lower limit decreases with the increase in resources. Meanwhile, there is a negative correlation between the intensity of medical work and the proportion of distribution. Our work deepens our understanding of the role of Fangcang shelter hospitals in the pandemic and provides a reference for feasible strategies by which to contain the pandemic.

Simulation Study on Airflow Organization and Environment in Reconstructed Fangcang Shelter Hospital Based on CFD

With frequent outbreaks of COVID-19, the rapid and effective construction of large-space buildings into Fangcang shelter hospitals has gradually become one of the effective means to control the epidemic. Reasonable design of the ventilation system of the Fangcang shelter hospital can optimize the indoor airflow organization, so that the internal environment can meet the comfort of patients and at the same time can effectively discharge pollutants, which is particularly important for the establishment of the Fangcang shelter hospital. In this paper, through the reconstruction of a large-space gymnasium, CFD software is used to simulate the living environment and pollutant emission efficiency of the reconstructed Fangcang shelter hospital in summer under different air supply temperatures, air supply heights and exhaust air volume parameters. The results show that when the air supply parameters are set to an air supply height of 4.5 m, an air supply temperature of 18 °C, and an exhaust air volume of a single bed of 150 m3/h, the thermal comfort can reach level I, and the ventilation efficiency for pollutants can reach 69.6%. In addition, the ventilation efficiency is 70.1% and 70.3% when the exhaust air volume of a single bed is continuously increased to 200 and 250 m3/h, which can no longer effectively improve the pollutant emission and will cause an uncomfortable blowing feeling to patients.

Vaccination status for mild and asymptomatic infections with SARS-CoV-2 Omicron BA.2 variant in Shanghai.

This study aimed to evaluate the effects of different vaccine regimens on mild and asymptomatic infections with SARS-CoV-2 Omicron BA.2 variant in Shanghai. All asymptomatic patients and those with mild symptoms of Omicron infections were recruited from three major Fangcang shelter hospitals between March 26, 2022 and May 20, 2022. Nucleic acid for SARS-CoV-2 by real-time reverse-transcription polymerase chain reaction methods in nasopharyngeal swabs was assessed every day during the hospitalization. The value of cycle threshold lower than 35 was considered as positive result of SARS-CoV-2. A total of 214 592 cases were included in this study. The proportion of the asymptomatic patients was 76.90% and 23.10% of the recruited patients had mild symptoms. The median (interquartile range [IQR]: 25-75) duration of viral shedding (DVS) was 7 (5-10) days among all participants. The DVS varied greatly among different age groups. Children and the elderly had longer DVS compared with the adults. The booster shot of inactivated vaccine contributed to the shorter DVS in patients aged ≥70 years compared with the unvaccinated patients (8 [6-11] vs. 9 [6-12] days, p = 0.002]. Full inactivated vaccine regimen contributed to the shorter DVS in patients aged 3-6 years (7 [5-9] vs. 8 [5-10] days, p = 0.001]. In conclusion, the full inactivated vaccine regimen on children aged 3-6 years and booster inactivated vaccine regimen on the elderly aged ≥70 years appeared to be effective in reducing DVS. The booster vaccine regimen should be rigorously promoted and implemented.

Early-stage predictors of deterioration among 3145 nonsevere SARS-CoV-2-infected people community-isolated in Wuhan, China: A combination of machine learning algorithms and competing risk survival analyses.

To determine which early-stage variables best predicted the deterioration of coronavirus disease 2019 (COVID-19) among community-isolated people infected with severe acute respiratory syndrome coronavirus 2 and to test the performance of prediction using only inexpensive-to-measure variables. Medical records of 3145 people isolated in two Fangcang shelter hospitals (large-scale community isolation centers) from February to March 2020 were accessed. Two complementary methods-machine learning algorithms and competing risk survival analyses-were used to test potential predictors, including age, gender, severity upon admission, symptoms (general symptoms, respiratory symptoms, and gastrointestinal symptoms), computed tomography (CT) signs, and comorbid chronic diseases. All variables were measured upon (or shortly after) admission. The outcome was deterioration versus recovery of COVID-19. More than a quarter of the 3145 people did not present any symptoms, while one-third ended isolation due to deterioration. Machine learning models identified moderate severity upon admission, old age, and CT ground-glass opacity as the most important predictors of deterioration. Removing CT signs did not degrade the performance of models. Competing risk models identified age ≥ 35 years, male gender, moderate severity upon admission, cough, expectoration, CT patchy opacity, CT consolidation, comorbid diabetes, and comorbid cardiovascular or cerebrovascular diseases as significant predictors of deterioration, while a stuffy or runny nose as a predictor of recovery. Early-stage prediction of COVID-19 deterioration can be made with inexpensive-to-measure variables, such as demographic characteristics, severity upon admission, observable symptoms, and self-reported comorbid diseases, among asymptomatic people and mildly to moderately symptomatic patients.

Stress load and volunteer motivation of patient volunteers in Fangcang shelter hospitals in Shanghai, China during the COVID-19 pandemic: a cross-sectional survey

ObjectivesThis study aims to assess the volunteer motivation and stress load of patient volunteers in the Fangcang shelter hospitals (FSHs), examine their associations, and explore the potential influence factors of...

An optimal aggregation method for interval grey numbers using on Steiner-Weber point with application

Aiming at the problem of low accuracy of two-dimensional preference information aggregation, this paper takes two-dimensional interval grey numbers as an example to define its preference information mapping rules. This rule maps preference information to preference points on a two-dimensional plane. Based on the theory of plane Steiner-Weber point, we construct a two-dimensional optimal model, and prove the optimality of the model theoretically. Then, adopt plant growth simulation algorithm (PGSA) to solve the proposed model. The obtained optimal aggregation point that can represent the comprehensive opinions. Finally, by analyzing the selection problem of Fangcang shelter hospital and comparing it with the particle swarm optimization (PSO) method, we conclude that the sum of weighted Euclidean distance obtained by our method is minimal. The aggregation precision of our method is higher than that of other aggregation method to a certain extent.

Clinical Practice and Effectiveness Analysis of the Management of Corona Virus Disease 2019 Infected at Shanghai Fangcang Shelter Hospital: A Descriptive Study.

The Fangcang shelter hospital has gradually become the primary management mode in China's fight against this Corona Virus Disease 2019 (COVID-19) in 2020. In early 2022, the Fangcang shelter hospital management model was successfully applied to the new outbreak of COVID-19 in Shanghai also. Although Fangcang shelter hospitals are no longer the prevailing mode of prevention of COVID-19, the management experience of Shanghai makeshift hospitals is worthy of reference for public health. The authors conducted a descriptive statistical analysis of Hall 6-2 of the Shanghai National Convention and Exhibition Center Fangcang shelter hospital. The whole hall of the Fangcang shelter hospital was managed by the one hospital, and the inclusion of third-party management personnel alleviated the shortage of medical personnel human resources. Through practice, a new procedure for treating batch infected people was introduced. By optimizing ward management, 72 on-duty doctors, 360 on-duty nurses, 3 sense-control administrators, and 15 administrators cured 18,574 infected people in 40 days, and created a record of a doctor managing 700 infected people without compromising the quality of treatment. There have been no deaths and no complaints from the infected people located in Hall 6-2 of the Shanghai National Convention and Exhibition Center Fangcang shelter hospital. Compared with previous data, the new management mode of Fangcang shelter hospitals provides a reference for the management of the new infectious diseases for public health.

Application of SHEL Model in the Management of Respiratory Tract Exposure in Fangcang Shelter Hospitals for COVID-19.

To explore the application effect of the (software factors, hardware factors, environmental factors, parties and other factors, SHEL) model in respiratory tract exposure protection of staff in temporary COVID-19 hospitals. 207 Staff members working in the isolation units of Fangcang shelter hospitals between 20 May 2022 and 5 June 2022 were selected as research subjects. The SHEL model was used to protect and manage the respiratory exposure of the isolation unit staff to the novel coronavirus. The incidence of respiratory exposure among the staff in the isolation units was compared before the SHEL model's implementation (20 May 2022-28 May 2022) and afterwards the SHEL model's implementation (29 May 2022-5 June 2022). Before the implementation of the SHEL model, a total of nine cases (4.35%) from 207 workers had respiratory exposure. Occurrence location: six cases in the isolation room (one-out room, level-one protection zone) and three cases in the drop-off area for patients outside the ward. After implementation, a total of two cases (0.97%) of respiratory tract exposure occurred among the 207 staff members; both occurred in the unprotected zone (two-out room, level-two protection zone), and the difference was statistically significant before and after the implementation (P < 0.05). New coronary pneumonia Fangcang shelter hospitals should use the SHEL model to manage the respiratory exposure of their isolation unit staff to reduce the respiratory exposure risk to staff in isolation units.

Characteristics and Occurrence Scenarios of Staff Exposed to SARS-CoV-2 Omicron in Shanghai Lingang Fangcang Shelter Hospital, CHINA.

To analyze the characteristics and occurrence scenarios of occupational exposure of staff in the Shanghai Lingang Fangcang Shelter Hospital. We collected the data of 80 staff with occupational exposure (including doctors, nurses, cleaning, security guards, and maintenance staff) in the Shanghai Lingang Fangcang Shelter Hospital from April 5 to May 20, 2022. The basic information of occupational exposure, factors influencing different occupational exposure types, ways to discover occupational exposure, discovery places of occupational exposure, and specific occurrence scenarios were compiled and analyzed among these data. Occupational exposure mainly occurred in nurses (37, 46.25%), and cleaning (21, 26.25%). After the occurrence of occupational exposure, 20 staff (25%) did not know the occurrence time. Moreover, occupational exposure types were listed from high to low proportion as follows: broken protective clothing (56, 70%), mask loosening or displacement (13, 16.25%), skin exposure (6, 7.5%), and sharp object injuries (5, 6.25%). Occupational exposure was discovered mainly through self-discovery (56, 70%), while other discovery ways were majorly colleague discovery (12, 15%) and infection control supervisor discovery (12, 15%). Furthermore, occupational exposure was discovered principally in the public area (53.75%) and the office area (25%) of the cabin, but the proportion of mask loosening or displacement (38.46%) and skin exposure (50%) was also high in the first unloading area. Broken protective clothing occurred in the following scenarios: scratching while working in the cabin (37, 66.07%) and not knowing its occurrence time (25%). The occurrence scenarios of mask loosening or displacement were mainly not knowing its occurrence time (6, 46.15%), self-discovery (3, 23.08%), and at the time of removal (3, 23.08%). Targeted training and prevention of occupational exposure should be performed to decrease infection risk and ensure staff safety in Fangcang shelter hospitals.

Delayed Model for the Transmission and Control of COVID-19 with Fangcang Shelter Hospitals

The ongoing coronavirus disease 2019 (COVID-19) pandemic poses a huge threat to global public health. Motivated by China’s experience of using Fangcang shelter hospitals (FSHs) to successfully combat the epidemic in its initial stages, we present a two-stage delay model considering the average waiting time of patients’ admission to study the impact of hospital beds and centralized quarantine on mitigating and controlling of the outbreak. We compute the basic reproduction number in terms of the hospital resources and perform a sensitivity analysis of the average waiting times of patients before admission to the hospitals. We conclude that, while designated hospitals save lives in severely infected individuals, the FSHs played a key role in mitigating and eventually curbing the epidemic. We also quantified some key epidemiological indicators, such as the final size of infections and deaths, the peak height and its timing, and the maximum occupation of beds in FSHs. Our study suggests that, for a jurisdiction (region or country) still struggling with COVID-19, when possible, it is essential to increase testing capacity and use a centralized quarantine to massively reduce the severity and magnitude of the epidemic that follows.

Dynamics of disease characteristics and viral RNA decay in patients with asymptomatic and mild infections during the Omicron wave in Shanghai, China: A retrospective cohort study

ObjectivesAsymptomatic infections and mild diseases were more common during the Omicron outbreak in Shanghai, China in 2022. This study aimed to assess the characteristics and viral RNA decay between patients with asymptomatic and mild infections. MethodsA total of 55,111 patients infected with SARS-CoV-2 who were quarantined in the National Exhibition & Convention Center (Shanghai) Fangcang shelter hospital within 3 days after diagnosis from April 9 to May 23, 2022 were enrolled. The kinetics of cycle threshold (Ct) values of reverse transcription-polymerase chain reaction were assessed. The influencing factors for disease progression and the risk factors for the viral RNA shedding time (VST) were investigated. ResultsOn admission, 79.6% (43,852/55,111) of the cases were diagnosed with asymptomatic infections, and 20.4% were mild diseases. However, 78.0% of initially asymptomatic subjects developed mild diseases at the follow-up. The final proportion of asymptomatic infections was 17.5%. The median time of symptom onset, the duration of symptoms, and the VST were 2 days, 5 days, and 7 days, respectively. Female, age 19-40 years, underlying comorbidities with hypertension and diabetes, and vaccination were associated with higher risks of progressing to mildly symptomatic infections. In addition, mildly symptomatic infections were found to be associated with prolonged VST compared with asymptomatic infections. However, the kinetics of viral RNA decay and dynamics of Ct values were similar among asymptomatic subjects, patients with asymptomatic-to-mild infection, and patients with mild infection. ConclusionA large proportion of initially diagnosed asymptomatic Omicron infections is in the presymptomatic stage. The Omicron infection has a much shorter incubation period and VST than previous variants. The infectivity of asymptomatic infections and mildly symptomatic infections with Omicron is similar.

Effects of dysfunctional beliefs about sleep on sleep quality and mental health among patients with COVID-19 treated in Fangcang shelter hospitals.

With the COVID-19 pandemic in China, a large number of mild or ordinary confirmed cases have been sent to Fangcang shelter hospitals for treatment. We aimed to investigate the mental health condition of Fangcang patients 2 years after the pandemic when patients knew more about COVID-19 and the virus was less virulent. We focused on the effect of dysfunctional beliefs and attitudes about sleep on depression, anxiety, and insomnia. A total of 1,014 patients from two large Fangcang shelter hospitals in Shanghai between 22 April and 8 May 2022 completed a set of questionnaires comprising: the Dysfunctional Beliefs and Attitudes about Sleep scale, the Generalized Anxiety Disorder scale, the Patient Health Questionnaire, and the Insomnia Severity Index scale. Results show that the positive screening rates for anxiety, depression, and insomnia among tested patients were 55.3, 27.0, and 47.8%, respectively. Patients were more likely to report higher anxiety, depression, and insomnia, and to endorse affective and sleep disorders if they were: female, aged 18-40 years, with undergraduate course or above, white-collar employees, or those who thought the pandemic would have severe economic effects. About 51.4% of the participants had dysfunctional beliefs about sleep to varying degrees. Compared with patients who had accurate beliefs about sleep, the ratios of insomnia, anxiety, and depression were significantly higher among patients with dysfunctional beliefs about sleep. Attention should be paid to the mental health problems of patients in Fangcang shelter hospitals. The results indicate that dysfunctional beliefs about sleep significantly increased anxiety, depression, and insomnia of Fangcang patients.

Risk factor analysis of omicron patients with mental health problems in the Fangcang shelter hospital based on psychiatric drug intervention during the COVID-19 pandemic in Shanghai, China.

The widespread coronavirus disease 2019 (COVID-19) outbreak impacted the mental health of infected patients admitted to Fangcang shelter hospital a large-scale, temporary structure converted from existing public venues to isolate patients with mild or moderate symptoms of COVID-19 infection. This study aimed to investigate the risk factors of the infected patients from a new pharmacological perspective based on psychiatric drug consumption rather than questionnaires for the first time. We summarised the medical information and analysed the prevalence proportion, characteristics, and the related risk factors of omicron variants infected patients in the Fangcang Shelter Hospital of the National Exhibition and Convention Center (Shanghai) from 9 April 2022 to 31 May 2022. In this study, 6,218 individuals at 3.57% of all admitted patients in the Fangcang shelter were collected suffering from mental health problems in severe conditions including schizophrenia, depression, insomnia, and anxiety who needed psychiatric drug intervention. In the group, 97.44% experienced their first prescription of psychiatric drugs and had no diagnosed historical psychiatric diseases. Further analysis indicated that female sex, no vaccination, older age, longer hospitalization time, and more comorbidities were independent risk factors for the drug-intervened patients. This is the first study to analyse the mental health problems of omicron variants infected patients hospitalised in Fangcang shelter hospitals. The research demonstrated the necessity of potential mental and psychological service development in Fangcang shelters during the COVID-19 pandemic and other public emergency responses.

Stress load of Chinese nurses in Fangcang Shelter Hospitals during the COVID-19 pandemic: A latent profile analysis.

The Omicron wave of the COVID-19 pandemic significantly affected Shanghai, China, from March to June 2022. Numbers of Fangcang Shelter Hospitals (FSHs) were conversed from stadiums and exhibition centers to tackle the pandemic. This study aimed to identify the stress load profiles of nurses working in FSHs and explore the characteristics and factors influencing stress load profiles. Totally, 609 out of 700 FSH nurses (with an effective response rate of 87%) participated in an online survey investigating their socio-demographic information, work-related stressors, and stress load. Results of the latent profile analysis identified four classes of stress load, which were labeled as the low (Class 1), mild (Class 2), moderate (Class 3), and high (Class 4) stress load class. Maternity status and self-perceived health condition were significantly different between the four stress load classes by comparisons using the Chi-square test and the Kruskal-Wallis test. The contributors to the stress load profiles were determined by the multinomial logistic regression analysis, including age, education, maternity status, self-perceived health condition, working time in FSHs, and the four dimensions of work-related stressors. Participants who were less healthy (OR = 0.045, 95% CI:0.012,0.171), worked longer time in FSHs (OR = 40.483, 95% CI: 12.103,135.410), faced with more workload (OR = 3.664, 95% CI: 1.047,12.815), and worse working environment (OR = 12.274, 95% CI: 3.029,49.729) were more likely to be classified to the high stress load class. The task arrangement and working environment for FSH nurses should be optimized, and psychological training should be conducted routinely.

Clinical characteristics and risk factors analysis of viral shedding time in mildly symptomatic and asymptomatic patients with SARS-CoV-2 Omicron variant infection in Shanghai.

To analyze the clinical characteristics and risk factors of viral shedding time in mildly symptomatic and asymptomatic patients with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant (BA.2 and BA2.2) infection in Shanghai, and the effect of traditional Chinese medicine (TCM) treatment, so as to provide a reference basis for epidemic prevention, control and clinical treatment. A total of 6,134 asymptomatic or mildly symptomatic Omicron-infected patients admitted to Tianhua Road fangcang shelter hospital in Jinshan, Shanghai, between April 2022 and May 2022 were included. Demographic characteristics and clinical histories were collected and compared in subgroups according to the different durations of viral shedding. Spearman's correlation analysis was performed to explore the association between virus shedding time and clinical variables. Multiple linear regression was used to evaluate the risk factors for viral shedding time. Most patients with asymptomatic and mildly symptomatic Omicron infection were male, and more than half of patients had a viral shedding time of 8-15 days. The patients were divided into three groups according to the time of viral shedding: short-duration (≤ 7 days), intermediate-duration (8-15 days) and long-duration group (≥16 days). The proportion of patients aged ≤ 29 years was the highest in the short-duration group (30.2%), whereas the proportion of patients aged 50-64 yeas was the highest in the long-duration group (37.9%). The proportion of patients with the chronic non-communicable diseases among the short-, intermediate- and long-duration groups was 6.2, 9.4, and 14.9%, respectively. Among them, hypertension was the most found (4.9, 7.8, and 11.7%, respectively). By multivariate analyses, we identified that viral shedding time of Omicron variants was independently negatively correlated with male patients, TCM treatment, and manual laborers, while it was independently positively associated with age and hypertension. Additionally, TCM treatment could significantly shorten the length of viral shedding time, especially for men, age ≥30 years, comorbid chronic non-communicable diseases, unemployed people and manual worker. Our results suggested that age and hypertension were independent risk factors for the duration of viral shedding in asymptomatic and mildly symptomatic omicron infected patients. TCM can effectively shorten viral shedding time.

Association between immunity and viral shedding duration in non-severe SARS-CoV-2 Omicron variant-infected patients.

Coronavirus disease 2019 (COVID-19) is a respiratory-related disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). More than 200 countries worldwide are affected by this disease. The Omicron variant of SARS-CoV-2 is the major epidemic variant worldwide and is characterized by higher infectivity. However, the immunity and risk factors for prolonged viral elimination in patients with non-severe SARS-CoV-2 Omicron variant infections are unclear. Therefore, this study aimed to examine the relationship between immunity and duration of viral elimination in non-severe SARS-CoV-2 Omicron variant-infected patients in Shanghai. In total, 108 non-severe SARS-CoV-2 Omicron variant-infected patients from Shanghai New International Expo Center Fangcang Shelter Hospital were recruited in this study. They were further allocated to the early elimination (EE) and prolonged elimination (PE) groups according to SARS-CoV-2 nucleic acid positivity duration. Compared to patients with EE, those with PE had increased serum concentrations of interleukin (IL)-5, IL-6, and IL-8; higher neutrophil count and neutrophil-to-lymphocyte ratio (NLR); lower lymphocyte, eosinophil, and red blood cell counts; and lower concentrations of hemoglobin and albumin (ALB). In lymphocyte subpopulation analysis, lower numbers of CD3+ T cells, CD4+ T cells, CD8+ T cells, and NK cells and a higher CD4/CD8 ratio were observed in patients with PE. In addition, correlation analysis results revealed that cycle threshold values of SARS-CoV-2 Omicron variant ORF1ab and N were negatively correlated with IL-6 and IL-8 levels and positively correlated with eosinophil count in patients with COVID-19. Finally, multivariate regression analysis showed that ALB, CD4/CD8 ratio, NLR, and eosinophil count were predictors of the SARS-CoV-2 Omicron variant elimination. In this study, we identified that the ALB, CD4/CD8 ratio, NLR, and eosinophil count were risk factors for prolonged viral elimination in non-severe SARS-CoV-2 Omicron variant-infected patients. These factors might be efficient indicators in the diagnosis, evaluation, and prognosis monitoring of the disease.

Quantitative evaluation of the role of Fangcang shelter hospitals in the control of Omicron transmission: A case study of the outbreak in Shanghai, China in 2022

Since Omicron began to spread in China, Shanghai has become one of the cities with more severe outbreaks. Under the comprehensive consideration of the vaccine coverage rate, the number of Fangcang shelter hospital beds and the number of designated hospital beds in Shanghai, this paper established a deterministic compartmental model and used the Nelder-Mead Simplex Direct Search Algorithm and chi-square values to estimate the model parameters. we calculate ℛ0 = 3.6429 when the number of beds in the Fangcang shelter hospital is relatively tight in the second stage and ℛ0 = 0.4974 in the fifth stage when there are enough beds in both Fangcang shelter hospital and designated hospital. Then we perform a sensitivity analysis on ℛ0 by using perturbation of fixed point estimation of model parameters in the fifth stage, and obtain three parameters that are more sensitive to ℛ0, which are transmission rate (β1d), proportion of the infectious (η) and the hospitalization rate of asymptomatic infected cases (δ1). Through simulation, we obtain that if the hospitalization rate of asymptomatic infections δ2 > 0.9373 or the transmission rate β1b < 0.0467, the second stage of Omicron transmission in Shanghai can be well controlled. Finally, we find the measure that converting the National Convention and Exhibition Center (NECC) into a Fangcang shelter hospital has played an important role in curbing the epidemic. Whether this temporary Fangcang shelter hospital is not built or delayed, the cumulative number of confirmed cases will both exceed 100,000, and the cumulative asymptomatic infections will both exceed 1 million. In addition, for a city of 10 million people, we obtain that if a permanent Fangcang shelter hospital with 17,784 beds is built ahead of epidemic, there will be no shortage of beds during the outbreak of Omicron. Our findings enrich the content of the impact of Fangcang shelter hospital beds on the spread of Omicron and confirm the correct policy adopted by the Chinese government.

Analysis of the Protective Effect of Infection Controllers Supervising Third-Party Personnel Entering and Leaving Shanghai Fangcang Shelter Hospital.

To analyze the impact of the new supervision and management methods of infection controllers on the protection of third-party personnel entering and leaving Shanghai Fangcang shelter hospital, to provide a reference for the management of third-party personnel in Fangcang shelter hospitals. A total of 200 third-party personnel received with traditional supervision and management methods, and 156 received new supervision and management methods from the Fangcang shelter hospital of the Shanghai International Convention and Exhibition Center. The sociodemographic characteristics of third-party personnel, including gender, age, education level, work experience in fighting the epidemic with safety awareness, was analyzed. The effects of the two different management modes on the protection of third-party personnel were statistically analyzed by the Chi-square test or logistic regression analysis. There were statistically significant differences in the incidence of infection among third-party personnel in terms of age, education level, work experience in fighting the epidemic in traditional supervision and management group, and whether they accepted the new supervision and management model had statistically significant differences (p <0.05). The main causes of incorrect put on and take off protective clothing, such as wrong way to detach the face screen, wrong way to remove goggles, wrong way to undress protective clothing, wrong way to take off the shoe cover, hand washing steps omitted, are that causes infection of third-party personnel (p <0.05). The new supervision and management model can reduce the infection rate of third-party personnel in Fangcang shelter hospitals through planned and purposeful training in terms of different age groups, education levels, work experience, and acceptance of protection knowledge.