But Ace2 and TMPRSS 2 is sane in both Covid19/Delta and Omicron. Either these two types should infect similarily or shoud neither infect lower nor upper respiratory tract Means, nothing about immune response or immune protection on Omicron infection is yet clear? I.e. if soecific IgM and IgG antibodies are generated or not, if immunological memory after infection is achieved or not? If so how it can happen? Does our defence mechanisn do not consider that omicron is a harmful virus esp for long term?