Publication trends of research on COVID-19 and host immune response: A bibliometric analysis

Introduction As the first bibliometric analysis of COVID-19 and immune responses, this study will provide a comprehensive overview of the latest research advances. We attempt to summarize the scientific productivity and cooperation across countries and institutions using the bibliometric methodology. Meanwhile, using clustering analysis of keywords, we revealed the evolution of research hotspots and predicted future research focuses, thereby providing valuable information for the follow-up studies. Methods We selected publications on COVID-19 and immune response using our pre-designed search strategy. Web of Science was applied to screen the eligible publications for subsequent bibliometric analyses. GraphPad Prism 8.0, VOSviewer, and CiteSpace were applied to analyze the research trends and compared the contributions of countries, authors, institutions, and journals to the global publications in this field. Results We identified 2,200 publications on COVID-19 and immune response published between December 1, 2019, and April 25, 2022, with a total of 3,154 citations. The United States (611), China (353), and Germany (209) ranked the top three in terms of the number of publications, accounting for 53.3% of the total articles. Among the top 15 institutions publishing articles in this area, four were from France, four were from the United States, and three were from China. The journal Frontiers in Immunology published the most articles (178) related to COVID-19 and immune response. Alessandro Sette (31 publications) from the United States were the most productive and influential scholar in this field, whose publications with the most citation frequency (3,633). Furthermore, the development and evaluation of vaccines might become a hotspot in relevant scope. Conclusions The United States makes the most indispensable contribution in this field in terms of publication numbers, total citations, and H-index. Although publications from China also take the lead regarding quality and quantity, their international cooperation and preclinical research need to be further strengthened. Regarding the citation frequency and the total number of published articles, the latest research progress might be tracked in the top-ranking journals in this field. By analyzing the chronological order of the appearance of retrieved keywords, we speculated that vaccine-related research might be the novel focus in this field.

Establishment of a Big Data Monitoring Platform for Cinema Opening in the Postepidemic Era from the Perspective of Public Health

The emergence of COVID-19 has had a huge impact on people's lives around the world. With the vaccine and the effective policies of the government, the spread of the epidemic has been effectively contained. However, in the postepidemic era, public health and epidemic protection policies have forced the transformation of public places such as movie theaters. The cinema box office monitored by the traditional monitoring platform can no longer effectively reflect the opening of the transformed cinema. To make up for the shortcomings of the traditional monitoring platform, considering the large amount of data generated by the cinemas' online and offline platforms and public place codes, this study establishes an intelligent monitoring platform based on big data technology to monitor the opening of cinemas. The established intelligent monitoring platform can fully extract the feature information contained in numerous data collected from cinemas and output quantitative indicators that characterize the opening of cinemas based on the feature information. The performance of the established intelligent monitoring platform is analyzed through a case study. The research results show that the average relative error between the cinema opening indicators predicted by the intelligent monitoring platform and the real results is within 2%, which indicates that the intelligent monitoring platform has good prediction accuracy. In addition, the statistical analysis results show that the linear correlation coefficient between the predicted and real results is 0.9802 > 0.95, which further indicates the feasibility of the established intelligent monitoring platform to monitor the opening of cinemas in the postepidemic era.

Antibody Persistence and Safety through 6 Months after Heterologous Orally Aerosolised Ad5-nCoV in individuals primed with two-dose CoronaVac previously (preprint)

Background: Heterologous orally administered adenovirus type-5 vector-based COVID-19 vaccine (Ad5-nCoV) in individuals who were primed with two-dose CoronaVac (an inactivated SARS-CoV-2 vaccine, by Sinovac) previously, has been reported to be safe and highly immunogenic within 28 days post-boosting. However, antibody persistence and safety up to 6 months of this regimen are not been reported yet. Methods: This is a randomized, open label, single-center trial on safety and immunogenicity of heterologous boost immunization with an orally administered aerosolised Ad5-nCoV vs. homologous boost immunization with CoronaVac after two-dose priming with CoronaVac in Chinese adults aged 18 years and older (NCT05043259). We followed the participants in this trial, including 140 in the low-dose aerosolised Ad5-nCoV group, 139 in the high-dose aerosolised Ad5-nCoV group, and 140 in the CoronaVac group for 6 months. Neutralising antibodies (NAbs) against live wild-type SARS-CoV-2 virus and omicron variant, and receptor-binding domain (RBD)-specific IgG antibodies were detected in serum samples collected at 28 days, 3 months, and 6 months after the booster dose. Serious adverse events (SAEs) were documented till month 6. Results: The low-dose and high-dose heterologous boost immunisation groups had NAb GMTs against live wild-type SARS-CoV-2 of 1937.3 [95% CI 1466.9, 2558.4] and 1350.8 [95% CI 952.6, 1915.3], which were 26.4 folds and 18.4 folds higher than that the CoronaVac group did (73.5 [95%CI 52.3, 103.3]) at 28 days. The low-dose and high-dose heterologous boost immunisation groups had NAb GMTs against live wild-type SARS-CoV-2 of 530.1 (95% CI 412.5, 681.1) and 457.6 (95%CI 349.4, 599.2), which were 26.0 folds and 22.4 folds higher than that the CoronaVac group did (20.4 [95%CI 14.3, 29.1]) at 3 months, respectively. At 6 months, the low-dose and high-dose heterologous booster groups had NAb GMTs against live wild-type SARS-CoV-2 of 312.9 (95%CI 237.7, 411.8) and 251.1 (95%CI 178.2, 354.0), which were 30.1 folds and 24.1 folds higher than the CoronaVac group did (10.4 [95%CI 7.8, 14.0]), respectively. Additionally, the low-dose and high-dose heterologous booster groups had NAb GMTs against live omicron variant of 52.0 (95%CI 37.2, 72.6) and 23.1 (95%CI 15.7, 33.9) at 28 days, 27.9 (95% CI 18.8, 41.3) and 23.3 (95%CI 16.2, 33.3) at 3 months, 16.0 (95%CI 10.9, 23.5) and 12.0 (95%CI 8.5, 16.8) at 6 months, respectively. However, nearly all participants had no detectable NAbs for omicron variant in the CoronaVac group at either 28 days, 3 months, or 6 months. No vaccine-related SAEs were observed. Conclusions: These data suggested that heterologous aerosolised Ad5-nCoV following two-dose CoronaVac priming was safe and persistently more immunogenic than three-dose CoronaVac, although immune responses waned over time.

The Role of the Vascular Niche in Organ Fibrosis and COVID-19-Related Organ Damage and the Countermeasures adopted by Chinese and Western Medicine

The vascular niche is a microenvironment located around capillaries and is mainly composed of endothelial cells, pericytes, macrophages, lymphocytes, mesenchymal stem cells, and hematopoietic stem cells. Studies have found that the vascular niche not only functions to regulate cell growth and differentiation in normal tissues, but also has an important role in regulating fibrosis in various organs and tissues in disease states. Coronavirus disease 2019 (COVID-19) is a systemic disease that broke out in 2019, caused by SARS-CoV-2 infection, which results in pulmonary inflammation, systemic multi-organ damage, and an inflammatory cytokine storm. Recently, the vascular niche has been found to play a role in COVID-19-related multi-organ damage. In this review, we introduce the important role of the vascular niche in organ fibrosis and COVID-19-related organ damage, summarize some of the cellular signaling pathways in the vascular niche that promote fibrosis, and discuss the treatment of organ fibrosis in Traditional Chinese medicine and Western medicine.

Risk Contagion between Global Commodities from the Perspective of Volatility Spillover

Prices of oil and other commodities have fluctuated wildly since the outbreak of the COVID-19 pandemic. It is crucial to explore the causes of price fluctuations and understand the source and path of risk contagion to better mitigate systemic risk and maintain economic stability. The paper adopts the method of network topology to examine the path of risk contagion between China's and foreign commodities, focusing on the dynamic evolution and transmission mechanism of risk contagion during the pandemic. This research found that among China's commodities, energy, grain, and textiles are net recipients of risk contagion, while chemical products and metals are net risk exporters. Among international commodities, industries have positive risk spillover effects on metals and textiles. During the first phase of the pandemic, China's commodities were the main exporters of risk contagion. However, international industries and metals became the main risk exporters and exerted risk spillover on China's commodities in the second phase of the pandemic. Moreover, based on total volatility spillover index of commodities, the risk contagion among the commodities follows three paths: 'interest rate →commodities →money supply';, 'China's economic expectation →commodities →foreign economic expectation';, and 'commodities →consumer confidence';.

Transmission pattern of shigellosis in Wuhan City, China: a modelling study

The article aims to estimate and forecast the transmissibility of shigellosis and explore the association of meteorological factors with shigellosis. The mathematical model named Susceptible–Exposed–Symptomatic/Asymptomatic–Recovered–Water/Food (SEIARW) was used to explore the feature of shigellosis transmission based on the data of Wuhan City, China, from 2005 to 2017. The study applied effective reproduction number (Reff) to estimate the transmissibility. Daily meteorological data from 2008 to 2017 were used to determine Spearman's correlation with reported new cases and Reff. The SEIARW model fit the data well (χ2 = 0.00046, p > 0.999). The simulation results showed that the reservoir-to-person transmission of the shigellosis route has been interrupted. The Reff would be reduced to a transmission threshold of 1.00 (95% confidence interval (CI) 0.82–1.19) in 2035. Reducing the infectious period to 11.25 days would also decrease the value of Reff to 0.99. There was a significant correlation between new cases of shigellosis and atmospheric pressure, temperature, wind speed and sun hours per day. The correlation coefficients, although statistically significant, were very low (<0.3). In Wuhan, China, the main transmission pattern of shigellosis is person-to-person. Meteorological factors, especially daily atmospheric pressure and temperature, may influence the epidemic of shigellosis.

Omicron: a chimera of two early SARS-CoV-2 lineages (preprint)

The current global epidemiology of COVID-19 is now characterized by the emergence and rapid spread of the SARS-CoV-2 Omicron variant on a global scale 1,2 . Despite the variant’s prompt predominance, there remain knowledge gaps in its origin and evolution history 3–6 . Here, we show that Omicron lineage SARS-CoV-2 is characterized by the feature of chimera. It was generated by genomic recombination of two early PANGO lineages of SARS-CoV-2. In the recombination event, strains with medium or high circulating intensity like SARS-CoV-2/human/USA/COR-21-434196/2021 belonging to PANGO lineage BA.1 provided the fundamental genome and served as the major parents, while the rare lineage strains like SARS-CoV-2/human/IRN/Ir-3/2019 belonging to B.35, as the minor parents, hybridized their genomic fractions into the major genomes at position 21593-23118nt. This recombination event results in 22 amino acid residue substitutions for the variant of Omicron, including 16 in the pivotal RBD of the spike protein. These substitutions have led to some subtle variations in the spatial structure and the affinity to hACE2 receptor of the spike protein 7,8 , thereby raising concerns about the effectiveness of available vaccines and antibody therapeutics 9–12 . The global spread and explosive growth of the SARS-CoV-2 in human population increase opportunities for future recombination 13–15 .

Distribution of ABO Blood Groups and Their Association With Low Risk of Severe COVID-19 Infection in Patients (preprint)

Background: To date, only few studies have focused on the correlation between ABO blood groups and COVID-19 infection risk, especially gender differences in infection risk. Our study aimed to describe the ABO blood group distribution and its association with risk of severe COVID-19 infection for effective identification of the susceptible population. Method：From January 21 to February 20, 2020, we compared the ABO blood group distribution and gender distribution and performed a correlation analysis in severe, non-severe, and non-COVID-19 patients. Results The results showed that the laboratory indices were significantly different between blood type O and non-blood-type-O COVID-19 patients. This indicated that patients of the type O blood group had a relatively lower risk of severe COVID-19 infection than patients of other blood types; in particular, females with blood type O had a lower risk of severe COVID-19 infection than males. Conclusion: Herein, we report a potentially simple prediction decision system to minimize the risk of severe COVID-19 infection based on blood type. Special attention should be paid to patients with blood types other than type O to minimize their risk of severe COVID-19 infection.

Quality of life during the epidemic of COVID-19 and its associated factors among enterprise workers in East China (preprint)

Background: The COVID-19 related lockdown and home confinement might have an important impact on the quality of life in enterprise workers. We investigated the quality of life during the epidemic in enterprise workers who just returned to work, and assessed its potential influencing factors to have a better understanding of the impact of COVID-19 epidemic lockdown and home confinement. Methods: This was a cross-sectional study of enterprise workers conducted in Deqing and Taizhou, Zhejiang Province, China. The Chinese version of EQ5D was used to assess life quality, and information about general characteristics and COVID-19 related factors was collected by a structured questionnaire, which was distributed through the social application “WeChat”. Results: A total of 2,435 participants were enrolled, 59.5% of which worked in Deqing. About 50% of the participants reported worries about the COVID-2019 epidemic and 40.1% had a centralized or home quarantine during the epidemic. The mean EQ-5D score and VAS were 0.990 and 93.5. Multiple logistic regression showed that the quality of life measures was related to physical activities (ORad=0.46) and keeping home ventilation (ORad=0.04) in Deqing, and were related to wearing a mask when going out (ORad=0.35), keeping home ventilation (ORad=0.16), unmarried status (ORad=2.38) and having a centralized or home quarantine (ORad=1.64) in Taizhou,Conclusions: The quality of life for returning enterprise workers in areas with different risks of COVID-19 was affected by different factors. Associated factors identified from this study would help develop proper intervention measures for enterprise workers to reduce the impact of large-scale public health events like the COVID-19 on their quality of life.

Distribution of ABO blood groups and association to low risk of COVID-19 infection in patients (preprint)

Background Since December 2019, the novel coronavirus pandemic (COVID-19) has become a global health emergency. To date, studies on the correlation between ABO blood groups and COVID-19 infected risk had rarely reported. This study aimed to describe the ABO blood groups distribution and association to low risk of COVID-19 infection for effectively concerning about the susceptible population.Methods We included 138 COVID-19 diagnosed patients and 82 non- COVID-19 patients between January 21 and February 20, 2020.We compared ABO blood group distribution, gender distribution and correlation analysis in Severe, Non-severe and Non-COVID19 patients, and analyzed the laboratory indexes of type O and non-type O groups in COVID19 patients.Results The laboratory results were significantly difference between type O and non-type O COVID19 patients (P < 0.05). Patients with blood type O had lower risk of severe COVID-19 infection (χ2 = 4.066, p = 0.044, OR = 0.380), and especially, female with the type O blood had lower risk in deteriorating severe COVID19 infection (p = 0.049).Conclusion Patients with the blood group of type O had relatively lower risk of COVID19 infection, especially, female with the type O blood had lower risk in deteriorating severe COVID19 infection. We should concern more to the patients with non-type O blood to minimize the risk of COVID19 infection.

Clinical Features of COVID‐19 in a Young Man with Massive Cerebral Hemorrhage: Case Report (preprint)

COVID-19 is currently a pandemic in the world, can invade multiple systems, and has a high morbidity and mortality. So far, no cases of acute cerebrovascular disease have been reported. This article reports the clinical features of a COVID-19 patient whose first symptom was cerebral hemorrhage. More importantly, after the craniotomy, the patient had high fever and it was difficult to retreat. After cerebrospinal fluid testing, it was determined that an intracranial infection had occurred. After anti-infection and plasma infusion of the recovered person, the patient's symptoms gradually improved. This case suggests that COVID-19 may infringe on cerebral blood vessels and cause cerebral hemorrhage. Transfusion of plasma from rehabilitation patients is effective for critically ill patients.

Early chest computed tomography to diagnose COVID-19 from suspected patients: A multicenter retrospective study (preprint)

Objective: The purpose of this study is to distinguish the imaging features of COVID-19 with other chest infectious diseases and evaluate diagnostic value of chest CT for suspected patients. Methods: Adult suspected patients aged >18 years within 14 days who underwent chest CT scan and reverse-transcription polymerase-chain-reaction (RT-PCR) tests were enrolled. The enrolled patients were confirmed and grouped according to results of RT-PCR tests. The data of basic demographics, single chest CT features, and combined chest CT features were analyzed for confirmed and non-confirmed groups. Results: A total of 130 patients were enrolled with 54 cases positive and 76 cases negative. The typical CT imaging features of positive group were ground glass opacity (GGO), crazy-paving pattern and air bronchogram. The lesions were mostly distributed bilaterally, close to the lower lungs or the pleura. When features combined, GGO with bilateral pulmonary distribution and GGO with pleural distribution were more common, of which were 31 cases (57.4%) and 30 cases (55.6%) respectively. The combinations were almost presented statistically significant (P<0.05) except for the combination of GGO with consolidation. Most combinations presented relatively low sensitivity but extremely high specificity. The average specificity of these combinations is around 90%. Conclusions: The combinations of GGO could be useful in the identification and differential diagnosis of COVID-19, which alerts clinicians to isolate patients for treatment promptly and repeat RT-PCR tests until incubation ends.

A comparative multi-centre study on the clinical and imaging features of comfirmed and uncomfirmed patients with COVID-19 (preprint)

Background Previous studies had described the differences in clinical characteristics between ICU and non-ICU patients. However, seldom study focused on confirmed and unconfirmed groups. Our aim was to compare clinical and imaging characteristics of COVID-19 patients outside Hubei province between confirmed and unconfirmed group. Methods We retrospectively enrolled 163 consecutive adult patients with suspected COVID-19 from three tertiary hospitals in two provinces outside Hubei province from January 12, 2020 to February 13, 2020 and the differences in epidemiological, clinical, laboratory and imaging characteristics between the two groups were compared. Results This study enrolled 163 patients with 62 confirmed cases and 101 unconfirmed cases. Most confirmed patients were clustered (31, 50.0%) and with definite epidemiological exposure. Symptoms of COVID-19 were nonspecific, largely fever and dry cough. Laboratory findings in confirmed group were characterized by normal or reduced white blood cell count, reduced the absolute value of lymphocytes, and elevated levels of C-reactive protein (CRP) and accelerated Erythrocyte sedimentation rate (ESR). The typical chest CT imaging features of patients with confirmed COVID-19 were peripherally distributed multifocal GGO with predominance in the lower lung lobe. Compared with unconfirmed patients, confirmed patients had significantly higher proportion of dry cough, leucopenia, lymphopenia and accelerated ESR (P<0.05); but not with alanine aminotransferase, aspartate aminotransferase, D-dimer, lactic dehydrogenase, and myoglobin (P>0.05). Proportion of peripheral, bilateral or lower lung distribution and multi-lobe involvement, GGO, crazy-paving pattern, air bronchogram and pleural thickening in the confirmed group were also higher (P<0.05). Conclusions Symptoms of COVID-19 were nonspecific. Leukopenia, lymphopenia and ESR, as well as chest CT could be used as a clue for clinical diagnosis of COVID-19.