Presentation Information
[C05-04]Understanding the evolution of a 'stealth' phenotype of the SARS-CoV-2 Omicron variant
*Lucia Ramirez Torres1, Park Hyeongki2, Ryo Yamaguchi3, Shingo Iwami1 (1. Nagoya University (Japan), 2. Pusan National University (Korea), 3. Hokkaido University (Japan))
Keywords:
SARS-CoV-2,Evolution simulator,Genetic algorithm,Omicron variant
Lucía Ramírez Torres1, Hyeongki Park2, Ryo Yamaguchi3, Shingo Iwami1,*
1 interdisciplinary Biology Laboratory, Biological Science, School of Science, Nagoya University, Nagoya, Japan
2School of Biomedical Convergence Engineering, Pusan National University, Busan, South Korea
3Department of Advanced Transdisciplinary Sciences, Hokkaido University, Sapporo, Hokkaido, Japan
*Corresponding Author: Shingo Iwami (iwami.iblab@bio.nagoya-u.ac.jp)
In the process of evolutionary transitions among the pre-Alpha, Alpha, Delta, and Omicron variants of SARS-CoV-2, we found the durations of viral shedding were shortened, except for the Omicron variant, and the peak viral load was increased (from the pre-Alpha to Alpha variants) and advanced (from the Alpha to Delta variants). In particular, interestingly, while we found almost the same peak time for the Omicron BA.1 subvariant viral load with a similar duration of viral shedding, the comparison of peak viral load suggested a lower peak for the BA.1 subvariant than for the Delta variant. Using quantitative empirical data analysis and the multi-level population dynamics model, we suggested that nonpharmaceutical interventions such as isolation potentially plays the role of a human-mediated selection pressure for SARS-CoV-2 evolution [1]. However, the current framework of our multi-level model cannot explain the evolution of a “stealth” phenotype showing a decreased peak viral load [1,2]. In this study, we expanded our multi-level population dynamics model by incorporating variant-specific infectious efficacy and vaccine-induced protection against breakthrough infections. We investigated whether viral phenotypes, such as the BA.1 subvariant showing slower and/or lower peak viral load, can evolve. Given the potential emergence of new variants and pathogens in the future, it is crucial to consider the evolution of pandemic viruses when devising public health strategies.
References
[1] Sunagawa, J., Park, H., Kim, K.S. et al., Isolation may select for earlier and higher peak viral load but shorter duration in SARS-CoV-2 evolution, Nature Communications, 14(1):7395, 2023.
[2] Sunagawa, J., Komorizono, R., Park, H. et al., Contact-number-driven virus evolution: A multi-level modeling framework for the evolution of acute or persistent RNA virus infection, PLoS Comput Biol, 19(5):e1011173, 2023.
1 interdisciplinary Biology Laboratory, Biological Science, School of Science, Nagoya University, Nagoya, Japan
2School of Biomedical Convergence Engineering, Pusan National University, Busan, South Korea
3Department of Advanced Transdisciplinary Sciences, Hokkaido University, Sapporo, Hokkaido, Japan
*Corresponding Author: Shingo Iwami (iwami.iblab@bio.nagoya-u.ac.jp)
In the process of evolutionary transitions among the pre-Alpha, Alpha, Delta, and Omicron variants of SARS-CoV-2, we found the durations of viral shedding were shortened, except for the Omicron variant, and the peak viral load was increased (from the pre-Alpha to Alpha variants) and advanced (from the Alpha to Delta variants). In particular, interestingly, while we found almost the same peak time for the Omicron BA.1 subvariant viral load with a similar duration of viral shedding, the comparison of peak viral load suggested a lower peak for the BA.1 subvariant than for the Delta variant. Using quantitative empirical data analysis and the multi-level population dynamics model, we suggested that nonpharmaceutical interventions such as isolation potentially plays the role of a human-mediated selection pressure for SARS-CoV-2 evolution [1]. However, the current framework of our multi-level model cannot explain the evolution of a “stealth” phenotype showing a decreased peak viral load [1,2]. In this study, we expanded our multi-level population dynamics model by incorporating variant-specific infectious efficacy and vaccine-induced protection against breakthrough infections. We investigated whether viral phenotypes, such as the BA.1 subvariant showing slower and/or lower peak viral load, can evolve. Given the potential emergence of new variants and pathogens in the future, it is crucial to consider the evolution of pandemic viruses when devising public health strategies.
References
[1] Sunagawa, J., Park, H., Kim, K.S. et al., Isolation may select for earlier and higher peak viral load but shorter duration in SARS-CoV-2 evolution, Nature Communications, 14(1):7395, 2023.
[2] Sunagawa, J., Komorizono, R., Park, H. et al., Contact-number-driven virus evolution: A multi-level modeling framework for the evolution of acute or persistent RNA virus infection, PLoS Comput Biol, 19(5):e1011173, 2023.