Reduced airborne transmission of SARS-CoV-2 BA.1 Omicron virus in Syrian hamsters.

Kawaoka-laboratory: Five- to six-week-old female Syrian hamsters were inoculated IN with 103 PFUs of the B.1.617.2 (Delta) or BA.1 (Omicron) variant and used as donor animals (grey hamster) in an airborne and direct contact transmission setup. To summarize, the combined analysis from multiple groups using different isolates of the BA.1 Omicron variant demonstrate that BA.1 has reduced airborne transmission efficiency in Syrian hamsters compared to prior variants of SARS-CoV-2. Since the start of the COVID-19 pandemic, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has caused hundreds of millions of infections worldwide with more than 6.5 million confirmed deaths. [Extracted from the article]