Filariases are a group of vector – borne parasitic diseases of humans and other animals, caused by long, threadlike
worms (hence the name “filaria” from Latin) that in their mature adult stages reside in the lymphatics or in
connective tissue. Of the eight filarial parasites that commonly infect man three species account for most of the
pathology associated with these infections: the lymphatic dwelling filariae; Wuchereria bancrofti and Brugia malayi
and the skin dwelling Onchocerca volvolus. A study was undertaken to compare certain haematological parameters
viz. Hb content, total blood cell count (RBC and WBC), WBC differential count, platelet count, E.S.R, P.C.V, M.C.V,
M.C.H and M.C.H.C between normal persons and filaria affected patients coming for check-up in Primary Health
Centres in Arakkonam to find out any specific variations.