To examine the effectiveness of vaccines in real-world conditions, Vahidy, F., et al analyzed data from over 91,000 patients in the U.S. The authors determined that mRNA vaccines are over 95% effective at preventing COVID-19-related hospitalizations and deaths in fully vaccinated individuals. In partially vaccinated individuals, mRNA vaccines are 77% effective at preventing hospitalizations and 64.2% effective at preventing death, which are similar to results reported by Pritchard, E., et al and Hall, V. et al based on data from the U.K. For individuals who received a single COVID-19 dose, Vasileiou, E., et al found the Pfizer and BioNTech BNT162b2 mRNA vaccine 91% effective and the Oxford–AstraZeneca ChAdOx1 vaccine 88% effective at preventing hospitalizations. Overall, these data indicate that current vaccines are highly effective against SARS-CoV-2 and substantially reduce COVID-19 related hospitalizations and deaths.
This past week, the CDC also provided new risk assessment and masking guidance for indoor and outdoor activities, recommending everyone—vaccinated and unvaccinated—continue to wear a mask for all indoor activities. Mitigation measures such as mask wearing and wide-spread vaccination are especially important since COVID-19 cases continue to rise globally, with India setting a record for highest daily global total for a second week in a row. Increased cases can lead to emerging variants. The recently identified B.1.617 lineage carries the L452R substitution to the spike protein that may enable this variant lineage to escape the immune response. Yadav, P., et al demonstrated that sera from both convalescent and vaccinated individuals neutralized the B.1.617 variant lineage strain. Continued genomic surveillance will be important to inform public health measures and slow the spread of SARS-CoV-2.
This year, ASM Microbe is part of World Microbe Forum, a collaboration between ASM, FEMS, ASLM and ASV, taking place online 20-24 June 2021. This unique, global, online meeting will bring together researchers, industry professionals, students, educators and leaders in the microbial sciences from across the world all in one place. The registry will host the session “COVID-19 Research Registry: A Year of Progress” where some of our curators will provide an update on the advancement of SARS-CoV-2 research in the last year. Registration is now open, and we hope you can join us at World Microbe Forum.
How is the genome of SARS-CoV-2 evolving? What mechanism does the coronavirus use to target human cells? How does the immune system react to SARS-CoV-2?
Will serology provide the ultimate answer? Does the existence of the antibody equal protection due to antibody neutralization? How often should patients be tested?
What are the different kinds of vaccines? Do coronaviruses evolve to escape vaccines? What have we learned from work with Ebola virus and SARS vaccines development?
How does a pandemic start? How long will this pandemic last: can data models give us some hints? COVID-19 affects people differently depending on their age, how does this affect transmission? How does social distancing influence transmission rates?
Scientifically speaking, what is a coronavirus? What are the similarities and differences in structure and activities of SARS, MERS and SARS-CoV-2? What is the PK/PD of Remdesivir?
By Benjamin Neuman, Ph.D., Professor of Biology and GHRC Chief Virologist, Texas A&M University, College Station, Texas. Dr. Neuman is one of the curators of the registry.
When heading into an unfamiliar place, it helps to have a map. The study by Sun and coworkers provides exactly that—a map of RNA secondary structure in the SARS-CoV-2 genome that shows the ways that the long-strand viral RNA twists and folds. This study brings some new and impressive technology to bear on the question of viral RNA structure, and the decision of the authors to go the extra step and characterize RNA folding both in solution and inside an infected cell is an important step in SARS-CoV-2 RNA cartography.
The reason why this could be important is that we knew from previous work that coronavirus genomes contain multiple layers of encoded information. In addition to genes that can be expressed, sometimes from within other genes, there are also signals that help the viral replicase recognize and copy its own genome and shorter mRNAs, and help those genomes to be selectively packaged into new virions. Some RNA secondary structure elements serve as anchor points for binding of viral or possibly host proteins that functionalize and protect the viral genome. Notably, part of the 3’-untranslated region of betacoronaviruses is hypothesized to switch between 2 different conformations, which seem to be both an anchor point for the conserved nonstructural protein 9 and an essential feature for successful viral RNA replication. In other RNA viruses, like poliovirus, RNA structures serve as a base and template on which the primers for viral RNA synthesis are built. A recent study from Slanina, H., et al. brings new evidence that coronavirus replication may begin through a similar protein-primed RNA synthesis mechanism—if that turns out to be the case, then having an accurate map of RNA secondary structure could turn out to be even more valuable than anticipated.
Another idea that coronavirus researchers may be able to take from picornavirus research is that modified or isolated versions of key RNA secondary structure elements can be expressed in cells as powerful dominant negative inhibitors of virus growth. Next steps are likely to include a combination of reverse genetics analysis to better understand the implication of each conserved RNA structure element, aided by bioinformatics to highlight conserved structures and populate this map with important features. Development of RNA structure-based inhibitors, and further experiments to map which of the many folds in the SARS-CoV-2 genome are important for virus growth, could be a long journey. But at least now, for this journey, we have a map.
