COVID-19: Does Omicron cause less damage to the lungs?

He said,“A number of laboratory-based studies have now shown that the Omicron variant is less able to infect the lungs as well as other variants and, as a result, is leading to less patients being admitted with pneumonia who require oxygen and ventilators.”“We are seeing [that] the majority of patients infected with Omicron have mild disease that is more localized to the upper respiratory tract and that hospitalizations are not rising as fast as they have with prior variants,” Dr. Roberts added.“However, hospitalizations and deaths lag behind overall case counts, and as our cases are continuing to rise and set daily records, we ultimately need to wait several more weeks to get a full picture of disease severity here, in the United States.”A potential reason for the less severe infection of the lower respiratory tract by Omicron in the present studies could be the changes in the ability of this variant to enter cells in the lower respiratory tract.The Omicron variant carries a large number of mutations in the gene encoding the spike protein, which is expressed on the surface of the SARS-CoV-2 virus.The SARS-CoV-2 spike protein binds to the ACE2 receptor expressed on lung cells and helps the virus enter the cell. The animal and cell culture studies also suggest that Omicron may be more efficient at infecting the upper respiratory tract.Studies conducted during the early stage of the pandemic show an association between levels of SARS-CoV-2 in the upper respiratory tract and increased transmission.The faster replication of Omicron in the upper respiratory tract may thus explain its increased contagiousness.“[These studies] give rise to an attractive speculation that the increased replication in upper airway tissues may contribute to increased transmissibility, potentially both by increasing the exhaled viral load and by decreasing the number of viral particles needed to infect, although, to my knowledge, this has not been demonstrated definitively,” Dr. Kasson explained.The increased contagiousness of the Omicron variant may also be due to its ability to escape detection by antibodies.Previous SARS-CoV-2 infections and immunization with COVID-19 vaccines lead to the production of antibodies that neutralize the virus.