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.

Huashi baidu granule in the treatment of pediatric patients with mild coronavirus disease 2019: A single-center, open-label, parallel-group randomized controlled clinical trial.

Background: Since late February 2022, a wave of coronavirus disease 2019 (COVID-19) mainly caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant rapidly appeared in Shanghai, China. Traditional Chinese medicine treatment is recommended for pediatric patients; however, the safety and efficacy remain to be confirmed. We conducted a single-center, open-label, parallel-group randomized controlled trial to assess the efficacy and safety of a Chinese herb compound, Huashi Baidu granule (HSBDG) in pediatric patients with laboratory-confirmed mild COVID-19. Methods: 108 recruited children (aged 3-18 years) with laboratory-confirmed mild COVID-19 were randomly allocated 2:1 to receive oral HSBDG for five consecutive days (intervention group) and to receive compound pholcodine oral solution for five consecutive days (control group). The negative conversion time of SARS-CoV-2 nucleic acid and symptom scores were recorded. Results: The median negative conversion time of SARS-CoV-2 nucleic acid was significantly shorter in the intervention group than in the control group (median days [interquartile range (IQR)]: 3 [3-5] vs. 5 [3-6]; p = 0.047). The median total symptom score on day 3 was significantly lower in the intervention group than in the control group (median total symptom score [IQR]: 1 [0-2] vs. 2 [0-3]; p = 0.036). There was no significant differences in the frequency of antibiotic use and side effects between the two groups. Conclusion: HSBDG is a safe, effective oral Chinese herbal compound granule, which shows a good performance within the Omicron wave among pediatric patients.

Culturing Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) for Diagnosis and Genome Sequencing.

OBJECTIVE: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid detection "re-positive" phenomenon is encountered clinically. The accuracy of a viral nucleic acid test is crucial to prevent reintroduction of the virus into the community. This study evaluated the effect of virus culturing on increasing the sensitivity and specificity of real-time polymerase chain reaction (RT-PCR) detection and viral genomic sequencing. METHODS: A series of tenfold dilutions of a SARS-CoV-2 viral stock were conducted and cultured for either 24 or 48 hours. The viral load of cultured samples was determined by RT-PCR. The cultured and non-cultured samples of 1x 50% tissue culture infectious dose (TCID50) were sequenced using metagenomic next-generation sequencing. The depth and coverage of SARS-CoV-2 genome were measured. RESULTS: The lowest viral load detectable in a sample with RT-PCR was 0.01 TCID50. After a 24-h culture, the viral ORF 1ab and N-gene cycle threshold (CT) values were reduced by 4.4 points and 1 point, respectively. One TCID50 viral load of post 24-h culture revealed the sequence depth reached an average of 752 reads, compared with 0.15 in the nonculture; furthermore, the coverage was 99.99% while 6.42% in the nonculture. CONCLUSION: These results indicate that virus culturing can significantly increase the viral load, which can increase the certainty of true-positive detection of the viral nucleic acids, and improve the quality of virus genomic sequencing.

Huashi baidu granule in the treatment of pediatric patients with mild coronavirus disease 2019: A single-center, open-label, parallel-group randomized controlled clinical trial

Background: Since late February 2022, a wave of coronavirus disease 2019 (COVID-19) mainly caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant rapidly appeared in Shanghai, China. Traditional Chinese medicine treatment is recommended for pediatric patients;however, the safety and efficacy remain to be confirmed. We conducted a single-center, open-label, parallel-group randomized controlled trial to assess the efficacy and safety of a Chinese herb compound, Huashi Baidu granule (HSBDG) in pediatric patients with laboratory-confirmed mild COVID-19. Methods: 108 recruited children (aged 3–18 years) with laboratory-confirmed mild COVID-19 were randomly allocated 2:1 to receive oral HSBDG for five consecutive days (intervention group) and to receive compound pholcodine oral solution for five consecutive days (control group). The negative conversion time of SARS-CoV-2 nucleic acid and symptom scores were recorded. Results: The median negative conversion time of SARS-CoV-2 nucleic acid was significantly shorter in the intervention group than in the control group (median days [interquartile range (IQR)]: 3 [3–5] vs. 5 [3–6];p = 0.047). The median total symptom score on day 3 was significantly lower in the intervention group than in the control group (median total symptom score [IQR]: 1 [0–2] vs. 2 [0–3];p = 0.036). There was no significant differences in the frequency of antibiotic use and side effects between the two groups. Conclusion: HSBDG is a safe, effective oral Chinese herbal compound granule, which shows a good performance within the Omicron wave among pediatric patients.

Epidemiological, clinical, and household transmission characteristics of children and adolescents infected with SARS-CoV-2 Omicron variant in Shanghai, China: a retrospective, multicenter observational study.

OBJECTIVES: To describe the epidemiological, clinical, and household transmission characteristics of pediatric COVID-19 cases in Shanghai, China. METHODS: Pediatric patients with COVID-19 hospitalized in Shanghai from March-May 2022 were enrolled in this retrospective, multicenter cohort study. The symptoms and the risk factors associated with disease severity were analyzed. RESULTS: In total, 2620 cases (age range, 24 days-17 years) were enrolled in this study. Of these, 1011 (38.6%) were asymptomatic, whereas 1415 (54.0%), 190 (7.3%), and 4 (0.2%) patients developed mild, moderate, and severe illnesses, respectively. Household infection rate was negatively correlated with household vaccination coverage. Children aged 0-3 years, those who are unvaccinated, those with underlying diseases, and overweight/obese children had a higher risk of developing moderate to severe disease than children aged 12-17 years, those who were vaccinated, those without any underlying disease, and those with normal weight, respectively (all P <0.05). A prolonged duration of viral shedding was associated with disease severity, presence of underlying diseases, vaccination status, and younger age (all P <0.05). CONCLUSION: Children aged younger than 3 years who were not eligible for vaccination had a high risk of developing moderate to severe COVID-19 with a prolonged duration of viral shedding. Vaccination could protect children from COVID-19 at the household level.

Mycoplasma pneumoniae among Chinese Outpatient Children with Mild Respiratory Tract Infections during the Coronavirus Disease 2019 Pandemic.

Mycoplasma pneumoniae is a common pathogen causing respiratory disease in children. We sought to investigate the epidemiology of M. pneumoniae among outpatient children with mild respiratory tract infections (RTIs) during the coronavirus disease 2019 (COVID-19) pandemic. Eligible patients were prospectively enrolled from January 2020 to June 2021. Throat swabs were tested for M. pneumoniae RNA. M. pneumoniae IgM was tested by a colloidal gold assay. Macrolide resistance and the effect of the COVID-19 countermeasures on M. pneumoniae prevalence were assessed. Symptom scores, treatments, and outcomes were evaluated. Eight hundred sixty-two eligible children at 15 centers in China were enrolled. M. pneumoniae was detected in 78 (9.0%) patients. Seasonally, M. pneumoniae peaked in the first spring and dropped dramatically to extremely low levels over time until the next summer. Decreases in COVID-19 prevalence were significantly associated with decreases in M. pneumoniae prevalence (r = 0.76, P = 0.001). The macrolide resistance rate was 7.7%. The overall sensitivity and specificity of the colloidal gold assay used in determining M. pneumoniae infection were 32.1% and 77.9%, respectively. No more benefits for improving the severity of symptoms and outcomes were observed in M. pneumoniae-infected patients treated with a macrolide than in those not treated with a macrolide during follow-up. The prevalences of M. pneumoniae and macrolide resistance in outpatient children with mild RTIs were at low levels in the early stage of the COVID-19 pandemic but may have rebounded recently. The colloidal gold assay for M. pneumoniae IgM may be not appropriate for diagnosis of M. pneumoniae infection. Macrolides should be used with caution among outpatients with mild RTIs. IMPORTANCE This is the first and largest prospective, multicenter, active, population-based surveillance study of the epidemiology of Mycoplasma pneumoniae among outpatient children with mild respiratory tract infections (RTIs) during the COVID-19 pandemic. Nationwide measures like strict face mask wearing and restrictions on population movement implemented to prevent the spread of COVID-19 might also effectively prevent the spread of M. pneumoniae. The prevalence of M. pneumoniae and the proportion of drug-resistant M. pneumoniae isolates in outpatient children with mild RTIs were at low levels in the early stage of the COVID-19 pandemic but may have rebounded recently. The colloidal gold assay for M. pneumoniae IgM may be not appropriate for screening and diagnosis of M. pneumoniae infection. Macrolides should be used with caution among outpatients with mild RTIs.

COVID-MTL: Multitask learning with Shift3D and random-weighted loss for COVID-19 diagnosis and severity assessment.

There is an urgent need for automated methods to assist accurate and effective assessment of COVID-19. Radiology and nucleic acid test (NAT) are complementary COVID-19 diagnosis methods. In this paper, we present an end-to-end multitask learning (MTL) framework (COVID-MTL) that is capable of automated and simultaneous detection (against both radiology and NAT) and severity assessment of COVID-19. COVID-MTL learns different COVID-19 tasks in parallel through our novel random-weighted loss function, which assigns learning weights under Dirichlet distribution to prevent task dominance; our new 3D real-time augmentation algorithm (Shift3D) introduces space variances for 3D CNN components by shifting low-level feature representations of volumetric inputs in three dimensions; thereby, the MTL framework is able to accelerate convergence and improve joint learning performance compared to single-task models. By only using chest CT scans, COVID-MTL was trained on 930 CT scans and tested on separate 399 cases. COVID-MTL achieved AUCs of 0.939 and 0.846, and accuracies of 90.23% and 79.20% for detection of COVID-19 against radiology and NAT, respectively, which outperformed the state-of-the-art models. Meanwhile, COVID-MTL yielded AUC of 0.800 ± 0.020 and 0.813 ± 0.021 (with transfer learning) for classifying control/suspected, mild/regular, and severe/critically-ill cases. To decipher the recognition mechanism, we also identified high-throughput lung features that were significantly related (P < 0.001) to the positivity and severity of COVID-19.

Retrospective Study of Critically Ill COVID-19 Patients With and Without Extracorporeal Membrane Oxygenation Support in Wuhan, China.

Background: Extracorporeal membrane oxygenation (ECMO) might benefit critically ill COVID-19 patients. But the considerations besides indications guiding ECMO initiation under extreme pressure during the COVID-19 epidemic was not clear. We aimed to analyze the clinical characteristics and in-hospital mortality of severe critically ill COVID-19 patients supported with ECMO and without ECMO, exploring potential parameters for guiding the initiation during the COVID-19 epidemic. Methods: Observational cohort study of all the critically ill patients indicated for ECMO support from January 1 to May 1, 2020, in all 62 authorized hospitals in Wuhan, China. Results: Among the 168 patients enrolled, 74 patients actually received ECMO support and 94 not were analyzed. The in-hospital mortality of the ECMO supported patients was significantly lower than non-ECMO ones (71.6 vs. 85.1%, P = 0.033), but the role of ECMO was affected by patients' age (Logistic regression OR 0.62, P = 0.24). As for the ECMO patients, the median age was 58 (47-66) years old and 62.2% (46/74) were male. The 28-day, 60-day, and 90-day mortality of these ECMO supported patients were 32.4, 68.9, and 74.3% respectively. Patients survived to discharge were younger (49 vs. 62 years, P = 0.042), demonstrated higher lymphocyte count (886 vs. 638 cells/uL, P = 0.022), and better CO2 removal (PaCO2 immediately after ECMO initiation 39.7 vs. 46.9 mmHg, P = 0.041). Age was an independent risk factor for in-hospital mortality of the ECMO supported patients, and a cutoff age of 51 years enabled prediction of in-hospital mortality with a sensitivity of 84.3% and specificity of 55%. The surviving ECMO supported patients had longer ICU and hospital stays (26 vs. 18 days, P = 0.018; 49 vs. 29 days, P = 0.001 respectively), and ECMO procedure was widely carried out after the supplement of medical resources after February 15 (67.6%, 50/74). Conclusions: ECMO might be a benefit for severe critically ill COVID-19 patients at the early stage of epidemic, although the in-hospital mortality was still high. To initiate ECMO therapy under tremendous pressure, patients' age, lymphocyte count, and adequacy of medical resources should be fully considered.

How is China’s energy security affected by exogenous shocks? Evidence of China–US trade dispute and COVID-19 pandemic

The trade dispute between China and the United States (US) since 2018 and the global COVID-19 pandemic since 2020 has significantly impacted China’s economic development. As China’s energy sources heavily depend on imports, its economic viability is becoming more and more risky. This study proposes a novel conceptual framework, involving macroeconomic, industrial and geopolitical factors, to evaluate China’s energy security as a major player in the trade dispute. This study also provides a comprehensive strategy for policymakers to make better decisions on reforming renewable energy patterns to guarantee energy security and achieve geopolitical advantages. The PESTEL (political, economic, social, technical, environmental and legislative) and SWOT (strengths, weaknesses, opportunities and threats) analytical methods are applied to evaluate the factors and attributes of China’s energy development and energy security in the current background. The China-US bipartite game reciprocity model and the QSPM (Quantitative Strategic Planning Matrix) analysis are conducted to assess which energy security strategy and policy are more suitable to deal with China-US trade dispute. To enhance energy security, China should diversify its energy supply chain, develop new sources of energy supply, advance the shale gas technology, popularise cleaner power-generation plants, increase nuclear-energy safety, introduce energy-conservation measures, promote alternative-energy vehicles, engage in international energy diplomacy, and rebuild international energy transaction and settlement systems.

Best practice for infection prevention in pediatric respiratory clinics during the COVID-19 epidemic.

During the COVID-19 epidemic, it is important for ensuring infection prevention and control in the pediatric respiratory clinics. Herein, we introduced the practice of infection prevention and control in pediatric respiratory clinics in China. Triage measures for patients who visit respiratory clinics, quality control for pediatric respiratory clinics and other preventive measures for related examinations and treatment have been introduced in this review article.