A highly powerful nonspecific strategy to reduce COVID-19 deaths.

The coronavirus disease 2019 (COVID-19) pandemic caused by the coronavirus severe acute respiratory syndrome coronavirus 2 remains risky worldwide. We elucidate here that good IDM (isolation, disinfection, and maintenance of health) is powerful to reduce COVID-19 deaths based on the striking differences in COVID-19 case fatality rates among various scenarios. IDM means keeping COVID-19 cases away from each other and from other people, disinfecting their living environments, and maintaining their health through good nutrition, rest, and treatment of symptoms and pre-existing diseases (not through specific antiviral therapy). Good IDM could reduce COVID-19 deaths by more than 85% in 2020 and more than 99% in 2022. This is consistent with the fact that good IDM can minimize co-infections and maintain body functions and the fact that COVID-19 has become less pathogenic (this fact was supported with three novel data in this report). Although IDM has been frequently implemented worldwide to some degree, IDM has not been highlighted sufficiently. Good IDM is relative, nonspecific, flexible, and feasible in many countries, and can reduce deaths of some other relatively mild infectious diseases. IDM, vaccines, and antivirals aid each other to reduce COVID-19 deaths. The IDM concept and strategy can aid people to improve their health behavior and fight against COVID-19 and future pandemics worldwide.

Frameshift Mutations in the Microevolution and Macroevolution of Viruses (preprint)

Some nucleotide insertions or deletions (indels) in protein-coding open reading frames lead to frameshift mutations (FSMs) which can change amino acid sequences drastically. FSMs are widely distributed in the genomes of many organisms. However, few studies have been reported regarding frequencies of FSMs in microevolution or macroevolution. Many viruses evolve much more rapidly than cellular organisms, and they are hence suitable to investigate frequencies of FSMs in microevolution or macroevolution. In this report, we identified 667 FSMs in gene sequences of 13 virus families and each FSM changed approximately 11 amino acid residues on average. Of the FSMs, 89.21% were 2-indel compensatory FSMs, and the remaining were 1-, 3-, 4-, 5-indel FSMs. We found that FSMs usually occurred more frequently in the viruses of the same family with smaller sequence identities, and FSMs occurred in the sequences of with identities of 60.0-69.9% more frequently than in the sequences with identities of 90.0-99.9% or 80.0-89.9% by approximately 34.9 or 13.1 times on average. We also found FSMs occurred at different frequencies among genes in the same virus genome, among species in the same virus family, or among virus families (e.g., more frequently in Coronaviridae than in Orthomyxoviridae). These results suggest that FSMs are more frequent in the inter-species or macroevolution than in the intra-species or microevolution of viruses. They provide novel evidence for the hopeful monster hypothesis in evolutionary biology. They inspire researchers to investigate the roles, frequencies, features, and functions of FSMs in other viruses and cellular organisms.