IL6 and COVID-19: ,11 In contrast, utilizing a relatively severe COVID-19 animal model (resulting in fatalities and significant weight loss) in this study, we identified that it was IL6 and IL-1β, rather than CCL11 (also known as eotaxin-1), that played a pivotal role in mediating the inflammatory responses induced by SARS-CoV-2 spike protein S1 that led to brain fog.