Les activités annuelles de la francophonie en Chine (2020-2021)

2020-2021 is an exceptional period, difficult to summarize. The efforts of all French teachers have made it possible to keep Francophonie dynamic and active in China despite the troubles caused by the COVID-19 pandemic during the first six months of 2020. The year 2020 and the first six months of 2021 have proven to be particularly fruitful for Francophonie in China with the successful organization of numerous Francophone events.

A New Joint Approach with Temporal and Profile Information for Social Bot Detection

With the increasing popularity of online social networks (OSNs), a huge number of social bots have emerged. Social bots are involved in various cybercrimes like cyberbullying and rumor dissemination, which have seriously affected the normal order of OSNs. Nowadays, existing studies in this field almost focus on English OSNs like Twitter and Facebook. However, it is difficult to directly apply these detection technologies to Sina Weibo, which is one of the largest Chinese microblogging services in the world. In addition, social bots are evolving rapidly and time-consuming feature engineering may not perform well in detecting newly emerging social bots. In this paper, we propose a new joint approach with Temporal and Profile information for social bot detection (TPBot). The approach includes data collection module, feature extraction module, and detection module. To begin with, data collection module uses a web crawler to obtain user data from Sina Weibo. Next, the feature extraction module regards the user posts as temporal data to extract temporal-semantic and temporal-metadata features. Furthermore, this module extracts features based on users’ profile. Finally, a detection model based on BiGRU and attention mechanism is designed in the detection module. The results show that TPBot performs better than baselines with the F1-score of 0.9837 on the Sina Weibo dataset. Moreover, we have also conducted an experiment on the two datasets collected from Twitter to evaluate the generalization ability of TPBot. It is found that TPBot outperforms baselines on the new datasets and has good generalization ability.

Updated approaches against SARS-CoV-2

Novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lies behind the ongoing outbreak of coronavirus disease 2019 (COVID-19). There is a growing understanding of SARS-CoV-2 in virology, epidemiology, and clinical management strategies. However, no anti-SARS-CoV-2 drug or vaccine has been officially approved due to the absence of adequate evidence. Scientists are racing to develop a treatment for COVID-19. Recent studies have revealed many attractive therapeutic options, even if some of them remain to be further confirmed in rigorous preclinical models and clinical trials. In this minireview, we aim to summarize the updated potential approaches against SARS-CoV-2. We emphasize that further efforts are warranted to develop the safest and most effective approach.

Co-infections of SARS-CoV-2 with multiple common respiratory pathogens in infected children: A retrospective study.

ABSTRACT: Since the outbreak of coronavirus disease 2019 (COVID-19) in Wuhan, considerable attention has been paid on its epidemiology and clinical characteristics in children patients. However, it is also crucial for clinicians to summarize and investigate the co-infection of SARS-CoV-2 in children.We retrospectively reviewed the clinical manifestations, laboratory findings, and imaging characteristics of COVID-19 patients in co-infection group (CI, n = 27) and single infection group (SI, n = 54). Samples were tested for multiple pathogens.A high incidence (27/81, 33%) of co-infection in children with COVID-19 was revealed. The most frequent co-infected pathogen was mycoplasma pneumoniae (MP, 20/81, 25%), followed by virus (6/81, 7%), and bacteria (4/81, 5%). No significant difference in clinical characteristics, laboratory examinations, or hospital stay was observed between the patients with co-infections and those with monomicrobial, only lower in white blood cell counts (CI: 5.54 ±â€Š0.36 vs SI: 7.38 ±â€Š0.37, P = .002), neutrophil counts (CI: 2.20 ±â€Š0.20 vs SI: 2.92 ±â€Š0.23, P = .024) and lymphocyte counts (CI: 2.72 ±â€Š0.024 vs SI: 3.87 ±â€Š0.28, P = .006). Compared with the patients with monomicrobial, chest imaging of those with co-infections showed consolidation in more cases (CI: 29.6% vs SI: 11.1%, P = .038) and duration of positive in nucleic acid was shorter (CI: 6.69 ±â€Š0.82 vs SI: 9.69 ±â€Š0.74, P = .015).Co-infection was relatively common in children with COVID-19, almost 1/3 had co-infection, most commonly caused by MP. Co-infection did not cause a significant exacerbation in clinical manifestations.

Decreased complement C3 levels are associated with poor prognosis in patients with COVID-19: A retrospective cohort study.

OBJECTIVES: To describe the humoral immune feature of patients with coronavirus disease 2019 (COVID-19). METHODS: The levels of total immunoglobulins (IgG, IgM, IgA, and IgE), complement (C3, C4) results were retrospectively analyzed in COVID-19 patients. Univariable and multivariable logistic regression were performed to explore the risk factors associated with the in-hospital death. RESULT: A total of 236 patients were enrolled in this study, of which 169 were transferred to another institution or discharged (survival group) and 67 died in hospital (non-survival group). Compared with survivors, the levels of IgA and IgE in non-survivors increased significantly, and level of complement C3 decreased. Non-survivors also showed higher incidence of chest tightness, breath shortness and dyspnoea; higher levels of inflammatory indicators, leukocytes and neutrophils; and low levels of lymphocyte subsets. Multivariable regression showed increasing odds of in-hospital death associated with older age (HR: 1.099; 95%CI: 1.057-1.143; p < 0.0001), d-dimer greater (HR: 1.294; 95%CI: 1.138-1.473; p < 0.0001) and decreased complement C3 level (HR: 0.073; 95%CI: 0.007-0.722; p = 0.025) on admission. Finally, in survival COVID-19 patients whose humoral immunity was re-examined, C3 levels tended to increase, while in non-survivors it decreased. CONCLUSION: Low level of complement C3 may be an alert to the admitted COVID-19 patients with additional management. Inhibition of the complement pathway might be an effective therapeutic to COVID-19 patients.

Clinical characteristics, laboratory outcome characteristics, comorbidities, and complications of related COVID-19 deceased: a systematic review and meta-analysis.

BACKGROUND: At present, novel coronavirus disease 2019 (COVID-19) has become a serious global public health problem. The current meta-analysis aimed to find risk factors for the COVID-19-related death, helping to enhance the efficacy and reduce the mortality of COVID-19. METHODS: We searched PubMed, Embase, medRxiv, and Cochrane Library for articles published between January 1, 2020, and April 13, 2020. We statistically analyzed the risk factors of the COVID-19 deceased with meta-analysis. RESULTS: A total of 2401 patients in 15 articles were included in this study. Meta-analysis showed that 66.6% of COVID-19 deceased were male, with a median age of 69.9 years. Common symptoms of deceased included fever (70.6-100%), dyspnea (38.89-85.7%), cough (22.4-78%), and fatigue (22-61.9%). The incidence of hypertension, chronic cardiovascular disease, diabetes, and chronic cerebrovascular disease among the COVID-19 deceased were 38.56% (95% confidence interval (CI) 25.84 ~ 52.12%), 17.54% (95% CI 13.38 ~ 21.69%), 22.2% (95% CI 19.30 ~ 25.10%), and 15.58% (95% CI 10.05 ~ 21.12%), respectively. Compared with the surviving COVID-19 patients, the deceased had lower platelet levels (mean difference (MD) = - 39.35, 95% CI - 55.78 ~ - 22.93) and higher C-reactive protein (CRP) (MD = 80.85, 95% CI 62.53 ~ 99.18) and lactate dehydrogenase (LDH) (MD = 246.65, 95% CI 157.43 ~ 335.88) at admission. The most common complications of the deceased were acute respiratory distress syndrome (ARDS) (OR = 100.36, 95% CI 64.44 ~ 156.32) and shock (OR = 96.60, 95% CI 23.80 ~ 392.14). CONCLUSION: Most of the COVID-19 deceased were elderly males. Fever, dyspnea, dry cough, fatigue, hypertension, chronic cardiovascular and cerebrovascular disease, diabetes, and laboratory examinations showed low levels of platelet content, increased CRP and LDH were associated with the risk of dying. ARDS and shock were risk factors for death in COVID-19 patients.

Characteristics of Peripheral Lymphocyte Subset Alteration in COVID-19 Pneumonia.

BACKGROUND: In December 2019, novel coronavirus (SARS-CoV-2) pneumonia (COVID-19) was reported in Wuhan and has since rapidly spread throughout China. We aimed to clarify the characteristics and clinical significance of peripheral lymphocyte subset alteration in COVID-19. METHODS: The levels of peripheral lymphocyte subsets were measured by flow cytometry in 60 hospitalized COVID-19 patients before and after treatment, and their association with clinical characteristics and treatment efficacy was analyzed. RESULTS: Total lymphocytes, CD4+ T cells, CD8+ T cells, B cells, and natural killer (NK) cells decreased in COVID-19 patients, and severe cases had a lower level than mild cases. The subsets showed a significant association with inflammatory status in COVID-19, especially CD8+ T cells and CD4+/CD8+ ratio. After treatment, 37 patients (67%) showed clinical response, with an increase in CD8+ T cells and B cells. No significant change in any subset was detected in nonresponsive cases. In multivariate analysis, posttreatment decrease in CD8+ T cells and B cells and increase in CD4+/CD8+ ratio were indicated as independent predictors of poor efficacy. CONCLUSIONS: Peripheral lymphocyte subset alteration was associated with clinical characteristics and treatment efficacy of COVID-19. CD8+ T cells tended to be an independent predictor for COVID-19 severity and treatment efficacy.

Apparent and occult infections of medical staff in a COVID-19 designated hospital.

Since the outbreak of novel coronavirus (SARS-CoV-2)-infected pneumonia (COVID-19), numerous medical staff are fighting on the frontline. However, the possibility of occult infection in medical staff is ignored in many recent studies. Herein, we collected data in a COVID-19 designated hospital from January 22, 2020 to March 10, 2020. A total of 33 medical staff had at least one nucleic acid test of throat swab, immunoglobulin G (IgG) or IgM serum antibody test, and chest computed tomography (CT), were enrolled. Finally, we identified 25 cases (75.8%) were isolated for hospitalized treatment after positive virus detection. In addition, 4 cases who were all negative for nucleic acid test detection with no clinical symptoms, and none of their chest CT were abnormal. However, the results of serum IgG or IgM antibody test in these 4 cases were positive, suggesting the presence of occult infection. In conclusion, data from our single center indicated that SARS-CoV-2 had a high medical infection rate (29/33 = 87.9%) and might have a potential risk of occult infection.

Comparison of hospitalized patients with pneumonia caused by COVID-19 and influenza A in children under 5 years.

BACKGROUND: Since the outbreak of Coronavirus Disease 2019 (COVID-19) in Wuhan, considerable attention has been paid to its epidemiology and clinical characteristics in children. However, it is also crucial for clinicians to differentiate COVID-19 from other respiratory infectious diseases, such as influenza viruses. METHODS: This was a retrospective study. Two groups of COVID-19 patients (n=57) and influenza A patients (n=59) were enrolled. We analyzed and compared their clinical manifestations, imaging characteristics and treatments. RESULTS: The proportions of cough (70.2%), fever (54.4%) and gastrointestinal symptoms (14.1%) in COVID-19 patients were lower than those of influenza A patients (98.3%, P<0.001; 84.7%, P<0.001; and 35.6%, P=0.007; respectively). In addition, COVID-19 patients showed significantly lower levels of leukocytes (7.87 vs. 9.89×109L-1, P=0.027), neutrophils (2.43 vs. 5.16×109L-1, P<0.001), C-reactive protein (CRP; 3.7 vs. 15.1mg/L, P=0.001) and procalcitonin (PCT; 0.09 vs. 0.68mm/h, P<0.001), while lymphocyte levels (4.58 vs. 3.56×109L-1; P=0.006) were significantly higher compared with influenza A patients. In terms of CT imaging, ground-glass opacification in chest CT was more common in COVID-19 patients than in influenza A patients (42.1% vs. 15%, P=0.032). In contrast, consolidation was more common in influenza A patients (25%) than in COVID-19 patients (5.2%, P=0.025). CONCLUSION: The clinical manifestations and laboratory tests of COVID-19 children are milder than those of influenza A children under 5 years. Additionally, imaging results more commonly presented as ground-glass opacities in COVID-19 patients.

Neutrophil to CD4+ lymphocyte ratio as a potential biomarker in predicting virus negative conversion time in COVID-19.

BACKGROUND: Since December 2019, novel coronavirus (SARS-CoV-2)-infected pneumonia (COVID-19) occurred in Wuhan, and rapidly spread throughout China. Our study aimed to evaluate the robustness of neutrophil to CD4+ lymphocyte ratio (NCD4LR) in predicting the negative conversion time (NCT) of SARS-CoV-2 in COVID-19 patients. METHODS: Univariate and multivariate analysis were conducted to evaluate the independency of NCD4LR in predicting NCT. Receiver operating characteristic (ROC) curve analysis and area under the curve (AUC) were used to assess the diagnostic accuracy. RESULTS: Compared with low NCD4LR patients, patients with high NCD4LR had an older age; higher incidence of fever, fatigue, chest distress/breath shortness, severer disease assessment on admission; higher levels of inflammatory indicators; low levels of lymphocyte subsets, and a longer NCT. Multivariate analysis also identified NCD4LR as an independent risk factor for delayed NCT. ROC analysis showed that NCD4LR had a better performance than neutrophil to lymphocyte ratio in predicting the virus negative conversion within 2 weeks (AUC = 0.772), 3 weeks (AUC = 0.710), 4 weeks (AUC = 0.728), or 5 weeks (AUC = 0.815). CONCLUSION: This study suggests that NCD4LR is a potential and useful biomarker for predicting the virus negative conversion time in COVID-19 patients. Furthermore, due to the NCDLR value is easily calculated, it can be widely used as a clinical biomarker for disease progression and clinical outcomes in COVID-19 patients.

Rehospitalization of a Recovered Coronavirus Disease 19 (COVID-19) Child With Positive Nucleic Acid Detection.

Since December 2019, novel coronavirus-infected pneumonia (coronavirus disease 19) occurred in Wuhan and rapidly spread throughout China and beyond. During this period, increasing of reports found that several recovered patients from different hospitals showed positive results of nucleic acid test again soon after discharge. However, little attention has been paid to recovered children. Herein, we reported a case of 8-year-old recovered child, who was rehospitalized again because of unexplained fever.

The liver injury and gastrointestinal symptoms in patients with Coronavirus Disease 19: A systematic review and meta-analysis

BACKGROUNDS: Since December 2019, novel coronavirus (SARS-CoV-2)-infected pneumonia (COVID-19) occurred in Wuhan, and rapidly spread throughout China. Our study aimed to evaluate the association of liver injury and gastrointestinal symptoms (GIS) with the progression of COVID-19. METHODS: A comprehensive search was performed on the PubMed to identify eligible studies that summarized the liver injury and GIS in COVID-19. RESULTS: A total of 21 studies with 3024 patients were included. Up to 53% patients had liver dysfunctions and the degree of liver damage was associated the severity of the disease. The prevalence of diarrhoea, nausea/vomiting or abdominal pain in patients with COVID-19 were 9.1%, 5.2% and 3.5%, respectively. No significant was found in the prevalence of diarrhoea (OR, 1.24;95%CI, 0.90 to 1.72;I(2)=0%, P=0.19) and nausea/vomiting (OR, 1.24;95%CI, 0.57 to 2.69;I(2)=61%, P=0.58) between severe and non-severe patients. In addition, diarrhoea (OR, 1.22;95%CI, 0.50 to 2.98;I(2)=0%, P=0.66) and nausea/vomiting (OR, 1.09;95%CI, 0.46 to 2.62;I(2)=0%, P=0.84) were not associated with the prognosis of COVID-19 patients. CONCLUSIONS: The incidences of GIS in patients with COVID-19 is relatively low and are not associated with the COVID-19 progression. Gastroenterologists should pay more attention to the liver injury induced by SARS-CoV-2 during the course of infection.