FASCIOLOSIS IN PAKISTAN: ADULT AND EGG PHENOTYPING, RISK MAPPING AND SEROLOGICAL STUDIES IN SUB-TROPICAL PUNJAB

Abstract

Fasciolosis also known as fascioliasis is a highly pathogenic liver infection caused by F. hepatica and F. gigantica. The study was aimed to use morphological markers for identification of fasciolids, generation of risk maps and use of rapid and cost effective diagnostic tool to reduce the impact of fasciolosis on animal health. The phenotypic features of adults and eggs of fasciolid species infecting buffaloes from central Punjab area, Pakistan, have been studied to characterize the fasciolid populations involved. Morphometric analyses were made by applying standardized measurements with a computer image analysis system (CIAS). The current investigation is first time conducted in Pakistan to confirm the taxonomic status of fasciolids by comparing with other pure standard populations viz., F. hepatica of European Mediterranean origins and F. gigantica representing Burkina Faso (Africa). In these geographical areas there is no overlapping of both fasciolids species. Only parasites obtained from bovines were employed. The climatic factors influencing fascioliasis presence and potential spread were analyzed from five meteorological stations during 1990-2010. The fascioliasis forecast risk Mt and Wb-bs (Water-Budget-Based System) indices and NDVI (Normalized Difference Vegetation Index), known to be useful for fascioliasis assessment, were obtained and correlated with geographical distribution, seasonality patterns and two-decade evolution of fascioliasis in livestock throughout the province. These two climatic forecast indices and a remote sensing marker are used to characterize the climatic factors and the earth surface in order to ascertain the epidemiological complexity and time-lag dynamics of fascioliasis. The seroprevalence of fascioliasis was also determined in sub-tropical Punjab with the application of a very sensitive and xxxispecific ELISA test by using monoclonal antibodies which are able to detect even very low intensity infection. The MM3 Sero-ELISA was applied to check the status of fascioliasis. The increase of disease transmission risk in the lowlands should be highlighted, given that the largest part of the Punjab province includes low altitude, highly irrigated plains. The importance of livestock in this province makes this phenomenon to be given forecast priority assessment henceforth in order to establish the adequate control measures. The use of cost effective diagnostic tools would be helpful to reduce the impact of fascioliasis on animal health by selecting the appropriate anthelmintic treatment. An annual treatment scheme to effectively control the disease is finally recommended to be applied throughout the whole Punjab province.