"In view of the high amount of cytokines induced by SARS-CoV,22, 24 MERS-CoV,25, 26 and 2019-nCoV infections, corticosteroids were used frequently for treatment of patients with severe illness, for possible benefit by reducing inflammatory-induced lung injury. However, current evidence in patients with SARS and MERS suggests that receiving corticosteroids did not have an effect on mortality, but rather delayed viral clearance.27, 28, 29 Therefore, corticosteroids should not be routinely given systemically, according to WHO interim guidance."
https://www.thelancet.com/journals/lancet/article/PIIS0140-6...
from the Lancet article:
"In view of the high amount of cytokines induced by SARS-CoV,22, 24 MERS-CoV,25, 26 and 2019-nCoV infections, corticosteroids were used frequently for treatment of patients with severe illness, for possible benefit by reducing inflammatory-induced lung injury. However, current evidence in patients with SARS and MERS suggests that receiving corticosteroids did not have an effect on mortality, but rather delayed viral clearance.27, 28, 29 Therefore, corticosteroids should not be routinely given systemically, according to WHO interim guidance."