ABSTRACT
Although vaccines have been developed, mutations of SARS-CoV-2, especially the dominant B.1.617.2 (delta) and B.1.529 (omicron) strains with more than 30 mutations on their spike protein, have caused a significant decline in prophylaxis, calling for the need for drug improvement. Antibodies are drugs preferentially used in infectious diseases and are easy to get from immunized organisms. The current study combined molecular modeling and single memory B cell sequencing to assess candidate sequences before experiments, providing a strategy for the fabrication of SARS-CoV-2 neutralizing antibodies. A total of 128 sequences were obtained after sequencing 196 memory B cells, and 42 sequences were left after merging extremely similar ones and discarding incomplete ones, followed by homology modeling of the antibody variable region. Thirteen candidate sequences were expressed, of which three were tested positive for receptor binding domain recognition but only one was confirmed as having broad neutralization against several SARS-CoV-2 variants. The current study successfully obtained a SARS-CoV-2 antibody with broad neutralizing abilities and provided a strategy for antibody development in emerging infectious diseases using single memory B cell BCR sequencing and computer assistance in antibody fabrication.
ABSTRACT
Objective: To assess the stability of improvements in global respiratory virus surveillance in countries supported by the United States Centers for Disease Control and Prevention (CDC) after reductions in CDC funding and with the stress of the coronavirus disease 2019 (COVID-19) pandemic. Methods: We assessed whether national influenza surveillance systems of CDC-funded countries: (i) continued to analyse as many specimens between 2013 and 2021; (ii) participated in activities of the World Health Organization's (WHO) Global Influenza Surveillance and Response System; (iii) tested enough specimens to detect rare events or signals of unusual activity; and (iv) demonstrated stability before and during the COVID-19 pandemic. We used CDC budget records and data from the WHO Global Influenza Surveillance and Response System. Findings: While CDC reduced per-country influenza funding by about 75% over 10 years, the number of specimens tested annually remained stable (mean 2261). Reporting varied substantially by country and transmission zone. Countries funded by CDC accounted for 71% (range 61-75%) of specimens included in WHO consultations on the composition of influenza virus vaccines. In 2019, only eight of the 17 transmission zones sent enough specimens to WHO collaborating centres before the vaccine composition meeting to reliably identify antigenic variants. Conclusion: Great progress has been made in the global understanding of influenza trends and seasonality. To optimize surveillance to identify atypical influenza viruses, and to integrate molecular testing, sequencing and reporting of severe acute respiratory syndrome coronavirus 2 into existing systems, funding must continue to support these efforts.
Subject(s)
COVID-19 , Influenza Vaccines , Influenza, Human , COVID-19/epidemiology , COVID-19/prevention & control , Centers for Disease Control and Prevention, U.S. , Humans , Influenza, Human/epidemiology , Influenza, Human/prevention & control , Pandemics/prevention & control , Population Surveillance , United States/epidemiologyABSTRACT
Objective To assess the stability of improvements in global respiratory virus surveillance in countries supported by the United States Centers for Disease Control and Prevention (CDC) after reductions in CDC funding and with the stress of the coronavirus disease 2019 (COVID-19) pandemic. Methods We assessed whether national influenza surveillance systems of CDC-funded countries: (i) continued to analyse as many specimens between 2013 and 2021;(ii) participated in activities of the World Health Organization’s (WHO) Global Influenza Surveillance and Response System;(iii) tested enough specimens to detect rare events or signals of unusual activity;and (iv) demonstrated stability before and during the COVID-19 pandemic. We used CDC budget records and data from the WHO Global Influenza Surveillance and Response System. Findings While CDC reduced per-country influenza funding by about 75% over 10 years, the number of specimens tested annually remained stable (mean 2261). Reporting varied substantially by country and transmission zone. Countries funded by CDC accounted for 71% (range 61–75%) of specimens included in WHO consultations on the composition of influenza virus vaccines. In 2019, only eight of the 17 transmission zones sent enough specimens to WHO collaborating centres before the vaccine composition meeting to reliably identify antigenic variants. Conclusion Great progress has been made in the global understanding of influenza trends and seasonality. To optimize surveillance to identify atypical influenza viruses, and to integrate molecular testing, sequencing and reporting of severe acute respiratory syndrome coronavirus 2 into existing systems, funding must continue to support these efforts.
ABSTRACT
The coronavirus disease 2019 (COVID-19) outbreak has a substantial negative effect on the global transportation industry. Ride-sharing is an innovative means of transportation that is also affected by the COVID-19. How and when individuals adopt ride-sharing services under the COVID-19 context should be explored to reduce the influence of the COVID-19 on ride-sharing and promote the development of ride-sharing services. This research investigates the effect of ambiguity tolerance and environmental concern on potential users' intention toward adopting ride-sharing services and further examines how the COVID-19 affects their intention toward adopting ride-sharing services. Data from 964 potential users of ride-sharing services suggest that ambiguity tolerance and environmental concern directly and positively influence potential users' intention toward adopting ride-sharing services. In addition, both indirectly affect consumers' intention toward adopting ride-sharing services through perceived ease of use and perceived usefulness. Moreover, the perceived health threat negatively moderates the effect of ambiguity tolerance and environmental concern on consumers' intention toward adopting ride-sharing services. This study enriches the research on how and when ambiguity tolerance and environmental concern influence consumers' intention toward adopting ride-sharing services. Furthermore, this study highlights the moderating effect of perceived health threat under the COVID-19 context. Based on the empirical findings, practical implications are proposed for the providers and facilitators of ride-sharing services.
ABSTRACT
The coronavirus disease 2019 (COVID-19) outbreak has a substantial negative effect on the global transportation industry. Ride-sharing is an innovative means of transportation that is also affected by the COVID-19. How and when individuals adopt ride-sharing services under the COVID-19 context should be explored to reduce the influence of the COVID-19 on ride-sharing and promote the development of ride-sharing services. This research investigates the effect of ambiguity tolerance and environmental concern on potential users’ intention toward adopting ride-sharing services and further examines how the COVID-19 affects their intention toward adopting ride-sharing services. Data from 964 potential users of ride-sharing services suggest that ambiguity tolerance and environmental concern directly and positively influence potential users’ intention toward adopting ride-sharing services. In addition, both indirectly affect consumers’ intention toward adopting ride-sharing services through perceived ease of use and perceived usefulness. Moreover, the perceived health threat negatively moderates the effect of ambiguity tolerance and environmental concern on consumers’ intention toward adopting ride-sharing services. This study enriches the research on how and when ambiguity tolerance and environmental concern influence consumers’ intention toward adopting ride-sharing services. Furthermore, this study highlights the moderating effect of perceived health threat under the COVID-19 context. Based on the empirical findings, practical implications are proposed for the providers and facilitators of ride-sharing services.
ABSTRACT
This report summarizes the chronology, epidemiology and virology of influenza seasons between the end of 2019 and the end of 2020 in the temperate regions of the northern and southern hemispheres and the tropical and equatorial regions. Data on influenza activity during this period were derived primarily from reports published by national ministries of health and other official bodies and data reported to WHO through FluNet1 or FluID.2 Transmission characteristics, illness and mortality are presented by influenza transmission zone 3 in each temperate hemisphere and in the tropical zone. A small literature review was conducted on possible interactions between respiratory viruses to make hypotheses on the impact of COVID-19 on influenza circulation in 2020.