The virus variant omicron has replaced delta in its prevalence. It spreads more rapidly but does not cause fierce symptoms of the disease, i.e. the persons affected are unlikely to suffer from severe pulmonary lung inflammation and critical courses. Nevertheless, pneumonia can also occur.¹ The reason for the milder course is not yet known.

Now, scientists led by Prof. Denisa Bojkova from the University Hospital Frankfurt am Main, together with colleagues from the German Center for Infection Research, Frankfurt am Main site, researchers from the Fraunhofer Institute for Molecular Biology and Applied Ecology (IME) Frankfurt am Main, as well as from the University of Kent, UK, have described first results of a study. They observe that in the omicron variant, certain SARS-CoV-2 proteins known to inhibit the interferon response of host cells are mutated. Cellular defense mechanisms are therefore better able to defend against the virus.^{2, 3}

Original publication:
Bojkova, D., Widera, M., Ciesek, S. et al. Reduced interferon antagonism but similar drug sensitivity in Omicron variant compared to Delta variant of SARS-CoV-2 isolates. Cell Res (2022). https://doi.org/10.1038/s41422-022-00619-9

¹ Regarding "mild course" in Omicron:
https://ptaforum.pharmazeutische-zeitung.de/was-gilt-als-milder-krankheitsverlauf-130772/
² https://www.spektrum.de/news/interferon-antwort-wo-omikron-eine-schwachstelle-hat/1974772
³ https://www.scinexx.de/news/medizin/warum-omikron-weniger-krank-macht/