Since Giardia-infection may stimulate macrophages, we further defined monocytes as CD14+CD16+ and CD14+CD16- cells and observed significant lower number of CD14+CD16+ population at week 2 (p<0.0001), week 6 (p<0.0001) and week 14 (p<0.0001) as compared to controls. The gene discussed is CD14; the disease is giardiasis.