Omicron slow to infect the lungs: Hong Kong study

Omicron slow to infect the lungs: Hong Kong study

Part of: Prelims and GS-II – Health

Context According to the study by researchers from the LKS Faculty of Medicine at the University of Hong Kong, the Omicron variant of SARS-CoV-2 infects and multiplies faster than the Delta variant and original SARS-CoV-2 in the human bronchus. 

• The study may explain why it may transmit faster between people than previous variants.

Key findings of the study

• Omicron does not easily infect the lower lungs and this potentially explains why instances of severe disease are lower in cases involving Omicron. 
• Omicron replicated around 70 times higher than the Delta variant and the original SARS-CoV-2 virus over 24 hours.
• In contrast, the Omicron variant replicated less efficiently (more than 10 times lower) in the lung tissue than the original SARS-CoV-2 virus.
• The severity of disease is not determined only by virus replication but also by the host immune response, which may lead to dysregulation of the innate immune system. 
• By infecting many more people, a very infectious virus may cause more severe disease and death even though the virus itself may be less pathogenic.