IL18 and lymphopenia: • Total percentage CD4+ T and CD8+ T cells was significantly lower in the severe cases along with increase in total neutrophil percentage, indicating overall dysfunctional immune response.• Increased levels of IFN-γ, IL-1ra, IL-2ra, IL-6, IL-10, IL-18, HGF, CCL7, MIG, M-CSF, G-CSF, MIG-1a, CTACK, and IP-10.• IP-10, CCL7, and IL-1RA were higher in severe cases compared to moderate.• Lymphocytopenia and increased neutrophil count was suggested to correlate with disease severe.