[Scientific standards in parasitology in historical perspective].

An analysis of scientific standards in parasitology was carried out from the perspective of anthropology of knowledge - a new discipline that emerged from non-classical history science in the 1990s. The history of parasitology, its development and limitations, are presented in a broad socio-cultural context, as the answers of scientists to different social needs in historical periods. In parasitological history there are some periods characteristic for all newly emerging disciplines of natural science. The first systematic account of natural phenomena and their interpretations was initiated in the 16th century and continued till the mid 18th century. It was a period when the phenomena could not be explained in a proper way by the existing and accepted theories. The epidemic diseases were one of these phenomena which were interpreted based on ancient ideas, mostly humoral pathology. In the 16th century a new contagium concept of material factors (pathogenes) that could be spread by contact among humans or close association was formed. This hypothesis, however, was not widely accepted because it contradicted the well-established normative concepts in the European academic naturalism. The development of parasitology was stopped because of theoretical barriers and interpretation difficulties (non-materialistic standard of naturalism, humoral pathology and spontaneous theory). In the second half of the 18th century, the theoretical crisis in natural sciences gave a new impulse for many disciplines; among others, parasitology entered in its second stage of development. The collected observations were classified in a new way and in the context of new interpretations. The progress in parasitology was prompted by the intensified urbanization, rapid increase of European population as well as by wars connected with infections and epidemics. It resulted in two competitive research programs (the French and the German). On the basis of the same observations, they advanced different theoretical interpretations. The third period in the history of parasitology lasted from the mid 19th century to the end of World War I. At that time a common agreement was established in all Europe, with regard to interpretation of standards inspired by positivism, i.e. verification of empirical statements through observation. Parasitology emerged as a separate discipline. Theoretical barriers limiting its progress and setting the questions were overcome. The contagion concept was reinstated. The colonial conquests solving demography problem provided the most important social impulse for the progress in parasitology. It was supported by governments interested in having their colonies free from diseases, mainly malaria and other tropical diseases, and thus safe for the European pioneer settlers. There was also development of parasitological scientific institutions (institutes of tropical medicine) and didactics. After World War I parasitology entered the fruitful stage of discipline development which resulted in a division into subdisciplines and a progress of new scientific fields. Its theoretical standards have become fixed and provided a basis for preventive programmes against parasite diseases, supported financially by European goverments, USA and some other countries. Those programmes were executed both in the home countries and in the colonies. After World War II, in the fourth stage of parasitology development, attention was mainly paid to local natural environment in order to diagnose parasites and their vectors. At the same time, parasitology became an applied science practiced in many specialized centres not only at universities. Presently, the main aims of parasitology are studies on biodiversity of parasites and environmental protection in the developed countries, and within tropical medicine as the travel medicine, because of rapid increase of tourism.