As the global community is gradually recovering from the outcomes of the COVID-19 virus, Dr. Bacca, an assistant professor at the Univ of British Columbia, is exploring SARS-CoV-2 and related viruses to better equip us for potential pandemics.
Dr. Bacca employed his expertise in micromechanics, which is the investigation of extremely small components, to devise a straightforward mechanical model to explain how viruses replicate within cells. In his recent Journal, Dr. Bacca suggested that the replication mechanism for enveloped viruses, such as coronavirus, HIV, influenza, and hepatitis, tends to favor a certain size of virus particles.
According to Dr. Bacca, when a virus infiltrates a cell, it produces an abundance of replicates and coalesces to form nuclei within the cell. Consequently, the cell membrane begins to cover these nuclei and creates buds that project from the cell surface. Afterward, these buds are expelled, constituting the new virus progeny prepared to infect other cells.
Spike proteins, spread across the cell surface, are critical to this process as they cause the cell membrane to bend into a curved shape, encouraging bud formation. This curvature is important as it regulates the optimal size of the virus. Viruses that are too small or too large compared to the optimum size will have a higher energy barrier to replication, making it more difficult to reproduce or, in some cases, stopping it from replicating entirely.
According to Dr. Bacca, most viruses appear to exist within a range of 60 to 100 nanometers in diameter – the “Goldilocks zone.” He also postulates that the replication efficiency of a virus is much more influential than its infection efficiency over its lifetime, with replication usually taking 10 minutes, while the infection is typically accomplished in less than 60 seconds.