TREM1 and COVID-19: Within viral infections, TREM-1 has been associated with the production of pro-inflammatory cytokines [44,46,94,95,96], the inhibition of apoptosis in macrophages and microglia infected with HIV [43,48]; severe outcomes in hand, foot, and mouth disease (caused by enterovirus A71) [42]; progressive liver damage and cirrhosis onset in hepatitis B infection [96,97]; and hyperinflammation and severity of COVID-19 [98,99,100,101], among others.