Life changes and mental health among Chinese children and adolescents during the pandemic: a combination of cross-sectional, longitudinal and clustering studies (preprint)

The measures to prevent COVID-19 pandemic had caused significant life changes, which could be distressing for mental health among children and adolescents. We aimed to evaluate the short- and long-term effects of life changes on children’s mental health in a large Chinese cohort. Survey-based life changes during COVID-19 lockdown were measured among 7,829 Chinese students at Grade 1–9, including social contacts, lifestyles and family financial status. Clustering analysis was applied to identify potential patterns of these changes. Depressive and anxiety symptoms were measured using the Center for Epidemiologic Studies Depression Scale and Screen for Child Anxiety Related Emotional Disorders. Logistic regression models were used to investigate the associations between these changes, their patterns and the presence of depression/anxiety symptoms using both cross-sectional and longitudinal designs. We found that the prevalence of depression and anxiety symptoms decreased during pandemic (34.6–32.6%). However, during and shortly after lockdown, students who reported negative impacts on their study, social and outside activities and diet, and decreased electronic time and sugar-sweetened consumption, as well as family income decline and unemployment had increased risks of depressive/anxiety symptoms, and students with changed sleep time had increased depressive symptoms. These associations attenuated or disappeared one year later. Similar patterns were observed in clustering analysis, while only the group with severe impact on family financial status showed a sustained increase in depression symptoms. In summary, restrictive measures that changed children and adolescents’ daily life during COVID-19 lockdown showed negative effects on their mental health, with some commonalities and distinctions patterns in the manifestation of depression and anxiety symptoms.

Safety and immunogenicity of heterologous boost immunization with an adenovirus type-5-vectored and protein-subunit-based COVID-19 vaccine (Convidecia/ZF2001): a randomized, observer-blinded, placebo-controlled trial (preprint)

Background Heterologous boost vaccination has been proposed as an option to elicit stronger and broader, or longer-lasting immunity. We assessed the safety and immunogenicity of heterologous immunization with a recombinant adenovirus type-5-vectored COVID-19 vaccine (Convidecia) and a protein-subunit-based COVID-19 vaccine (ZF2001). Methods and Findings We did a randomized, observer-blinded, placebo-controlled trial in healthy adults previously received one dose of Convidecia. Participants were randomly assigned (2:1) to receive either ZF2001 (vaccine group) or a trivalent inactivated influenza vaccine (TIV) (placebo group) at either 28-day or 56-day intervals. For both regimens, all participants received the 2nd injection with ZF2001 at 4 months after a dose of ZF2001 or TIV, with three-dose schedules of Convidecia/Convidecia/ZF2001 at day 0, day 28 and month 5 (referred to as CV/ZF/ZF (D0-D28-M5)) and CV/ZF/ZF (D0-D56-M6), and two-dose schedules of CV/ZF (D0-M5) and CV/ZF (D0-M6). The primary outcome was the geometric mean titer (GMT) of the neutralizing antibodies against live SARS-CoV-2 virus 14 days after each boost vaccination. The safety outcome was 7-day reactogenicity, measured as solicited local or systemic adverse reactions after each vaccination. Between April 7, 2021, and May 6, 2021, 120 participants were enrolled, among whom 60 were randomly assigned to receive ZF2001 (n=40) or TIV (n=20) at a 28-day interval, and 60 were randomly assigned to receive ZF2001 (n=40) or TIV (n=20) at a 56-day interval. 113 (94.2%) participants received the 2nd injection with ZF2001 4 months after a dose of ZF2001 or TIV. A total of 26 participants (21.7%) reported solicited adverse events within 7 days post boost vaccinations, and all the reported adverse reactions were mild . Among participants receiving ZF001 as second dose, the GMTs of neutralizing antibodies increased to 58.4 IU/ml (42.8-79.8) in 0-28 regimen, and to 80.8 IU/ml (53.1-122.9) in 0-56 regimen at 14 days post first boost dose. The GMTs of neutralizing antibodies increased to 334.9 IU/ml (95% CI 230.4, 486.9) in C/Z/Z (D0-D28-M5) regimen, and 441.2 IU/ml (260.8, 746.4) in C/Z/Z (D0-D56-M6) regimen at 14 days after the third dose. Two-dose schedules of CV/ZF (D0-M5) and CV/ZF (D0-M6) induced comparable antibody level comparable with that elicited by three-dose schedules, with the GMTs of 282.9 IU/ml (142.5, 561.8) and 293.9 IU/ml (137.6, 627.9), respectively. Study limitations include the absence of vaccine effectiveness in real-world, and current lack of immune persistence data and the neutralizing antibodies to Omicron. Conclusions Heterologous boosting with ZF001 following primary vaccination of Convidecia is safe and more immunogenic than a single dose of Convidecia. These results support flexibility in cooperating viral vectored vaccines and recombinant protein vaccine. Trial Registration ClinicalTrial.gov NCT04833101

Viral receptor profiles of masked palm civet revealed by single-cell transcriptomics (preprint)

Civets are small mammals belonging to the family Viverridae. The masked palm civets (Paguma larvata) served as an intermediate host in the bat-to-human transmission of severe acute respiratory syndrome coronavirus (SARS-CoV) in 2003. Because of their unique role in the SARS outbreak, civets were suspected as a potential intermediate host of SARS-CoV-2, the etiological pathogen of the COVID-19 pandemic. Besides their susceptibility to coronaviruses, civets can also be infected by other viruses, such as canine distemper viruses, parvoviruses, influenza viruses, etc. Regarding the ecological and economical role of civets, it is vital to evaluate the potential threats from different pathogens to these animals. Receptor binding is a necessary step for virus entry into host cells. Understanding the distribution of receptors of various viruses provides hints to their potential tissue tropisms. Herein, we characterized the cell atlas of five important organs (the frontal lobe, lung, liver, spleen and kidney) of masked palm civets (Paguma larvata) and described the expression profiles of receptor associated genes of 132 viruses from 25 families, including 16 viruses from 10 families reported before that can attack civets and 116 viruses with little infection record.

Ultrapotent SARS-CoV-2 neutralizing antibodies with protective efficacy against newly emerged mutational variants (preprint)

Accumulating mutations in the SARS-CoV-2 Spike (S) protein can increase the possibility of immune escape, challenging the present COVID-19 prophylaxis and clinical interventions. Here, 3 receptor binding domain (RBD) specific monoclonal antibodies (mAbs), 58G6, 510A5 and 13G9, with high neutralizing potency blocking authentic SARS-CoV-2 virus displayed remarkable efficacy against authentic B.1.351 virus. Each of these 3 mAbs in combination with one neutralizing Ab recognizing non-competing epitope exhibited synergistic effect against authentic SARS-CoV-2 virus. Surprisingly, structural analysis revealed that 58G6 and 13G9, encoded by the IGHV1-58 and the IGKV3-20 germline genes, both recognized the steric region S470-495 on the RBD, overlapping the E484K mutation presented in B.1.351. Also, 58G6 directly bound to another region S450-458 in the RBD. Significantly, 58G6 and 510A5 both demonstrated prophylactic efficacy against authentic SARS-CoV-2 and B.1.351 viruses in the transgenic mice expressing human ACE2 (hACE2), protecting weight loss and reducing virus loads. These 2 ultrapotent neutralizing Abs can be promising candidates to fulfill the urgent needs for the prolonged COVID-19 pandemic.

Questionnaire survey on occupational exposure of health care workers working in COVID-19 isolation wards of designated hospitals in 2020

OBJECTIVE: To investigate the status of occupational exposure of health care workers working in the COVID-19 isolation wards of designated hospitals so as to take targeted measures for occupational protection. METHODS By means of convenient sampling method, a self-designed questionnaire was applied to investigate the status of occupational exposure of health care workers who supported or worked in the designated hospitals for patients with COVID-19 from Mar. 1, to Mar. 5, 2020. RESULTS: Among the 293 health care workers working in the COVID-19 isolation wards, 28.00% had occupational exposure. The skin or hair' contacting with contaminated outer surface of personal protective equipment(PPE)(65.85%) was the most common type of occupational exposure. The removal of PPE(60.98%) and the operations that may generate aerosol(47.56%) were the major links where the occupational exposure took place. After the occupational exposure occurred, 68.29% of the health care workers carried out emergency treatment, and 71.95% of the health care workers were able to report the exposure according to standard procedures. The top 3 medical operations that were most likely to cause exposure were tracheotomy, bronchoscopy and endotracheal intubation. The top 3 nursing operations that were most likely to cause occupational exposure were artificial airway nursing, sputum suction and throat swab collection. The top 3 risk factors that were most likely to cause occupational exposure of health care workers were the implementation of operations that may generate aerosol, failure to comply with disinfection and isolation system, and sudden changes in the patients' condition for emergency rescue. CONCLUSION: There are varying degrees of occupational exposure among the health care workers working in the COVID-19 isolation wards of designated hospitals. It is necessary for the management department of medical institutions to formulate practical prevention and control measures according to the high frequency types, operation links and risk factors of the occupational exposure so as to reduce the risk of occupational exposure among the health care workers.

ACE2-Targeting Monoclonal Antibody As A "Pan" Coronavirus Blocker In Vitro and In A Mouse Model (preprint)

Coronaviruses have caused three major outbreaks of infectious disease since the beginning of 21st century. Broad-spectrum strategies that can be utilized in both current and future coronavirus outbreaks and mutation-tolerant are sought after. Here we report a monoclonal antibody 3E8 targeting human angiotensin-converting enzyme 2 (ACE2) neutralized pseudo-typed coronaviruse SARS-CoV-2, SARS-CoV-2-D614G, SARS-CoV and HCoV-NL63, without affecting physiological activities of ACE2 or causing toxicity in mouse model. 3E8 also blocked live SARS-CoV-2 infection in vitro and in a mouse model of COVID-19. Cryo-EM studies revealed the binding site of 3E8 on ACE2 and identified Histone 34 of ACE2 as a critical site of anti-viral epitope. Overall, our work has provided a potential pan coronavirus management strategy and disclosed a pan anti-coronavirus epitope on human ACE2 for the first time.