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Eggs with filaments were detected in the faeces of Macaca mulatta. On the basis of morphological indications and reports from the literature, this infection was most probably caused by the genus Ogmocotyle. Egg output and the onset of diarrhoea were arrested by treatment with 20 mg fenbendazole/kg body weight for 5 days in the form of medicated feed. Follow-up studies over 9 months showed neither new egg output nor the occurrence of clinical symptoms.

Bulls artificially infected with a varying number of metacercariae of Fasciola hepatica were kept under uniform, standardized laboratory conditions. 6 months after the infection the daily range of variation and the distribution of the Fasciola eggs in the faeces were determined 3 times a day (morning, noon and afternoon) over two test periods, each of 5 days. This test, carried out in over 800 individual faeces samples, showed that the excretion of Fasciola eggs over a period of several days fluctuates considerably within one animal and within one infection group; the excretion of Fasciola eggs over one day varies widely at different times in each animal and also in each infection group; the distribution of Fasciola eggs in the faeces is always irregular within one day and also over several days in all animals. The variations demonstrated here must be taken into consideration when assessing the results of coproscopical diagnosis because studies of the faeces carried out on a single occasion can lead to completely incorrect conclusions being drawn.

A series of suramin analogues has been synthesized in which the methyl groups of suramin have been replaced by hydrogen, alkyl, phenyl, and fluoro substituents, or which contain more than two methyl groups. The substances have been screened against Dipetalonema viteae in Meriones unguiculatus, Litomosoides carinii in Sigmodon hispidus and L. carinii in Mastomys natalensis, respectively. Small structural modifications have a marked influence on the antifilarial activity. There are marked differences between antifilarial and trypanocidal activities. A symmetrical molecule structure seems not to be essential for the antifilarial activity.

Following field observations, the ability of Fasciola hepatica to develop in domestic rabbits as compared with sheep was investigated under experimental conditions. The results indicate the development of F. hepatica is impaired in various phases after rabbit passage. Only 4.2 percent of the metacercariae gained after one rabbit passage developed to adult F. hepatica in sheep, whereas the respective percentage after sheep passage was 51.2 percent. It can be calculated that after rabbit passage 4.5 liver flukes develop from 100 F. hepatica eggs as compared with 2,141.3 parasites after sheep passage. The result justify the assumption that rabbits may play only a minor role in the epidemiology of fascioliasis.

More than 200 nitro compounds, most of them nitroaniline derivatives substituted with one or more radicals having a basic reaction, were prepared and investigated as to their therapeutic activity against bacteria, fungi, protozoa, helminths, viruses and tumors. Several mono-nitrobenzenes with a radical having a basic reaction showed weak in-vitro activity against gram-positive bacteria and against Crocker's sarcoma 180; they also showed systemic activity against nematodes (Aspiculuris tetraptera) and viruses. The majority of therapeutically active compounds with pronounced in-vivo activity against Trichomonas fetus, Entamoeba histolytica, Schistosoma mansoni, cestodes, nematodes (Ancylostoma caninum), viruses (influenza, MHV, SAV and EMC) and various types of carcinoma (Ehrlich's carcinoma, leukemia 1210, Crocker's sarcoma 180) were dinitrobenzene derivatives with one radical having a basic reaction and electropositive groups or unreactive or reactive chlorine atom, and di-nitrobenzene with two equal or two different radicals having a basic reaction. Compound No. 70 revealed a marked in-vitro activity against fungi (Trichophyton; Microsporum, Candida albicans). Other nitro compounds such as bis-mono- and bis-dinitrobenzene derivatives likewise showed a systemic action against E. histolytica, viruses and, in particular, carcinoma (Crocker's sarcoma 180, Ridgway's osteosarcoma). Oxygen and sulfur analogue compounds as well as compounds produced by reduction also possessed a distinct activity against E. histolytica and viruses. On the basis of the present results particularly the dinitrobenzenes substituted with two radicals having a basic reaction include a number which have in common that a structure/activity relationship is recognizable in respect of E. histolytica, Schistosoma mansoni and different types of viruses. The activity against viruses in this class of compounds is probably due to an increased interferon production in the host animal. Whether the mechanism of action is the same against E. histolytica or Schistosoma mansoni has not been determined so far. A tumorigenic effect was observed mainly in those di-nitrobenzenes which are classed as alkylating compounds. Because of the small chemotherapeutic index the trials were not continued with the most effective compounds mentioned.

The significance of tropical heminthiases for the populations of tropical countries is discussed and a survey on the incidence of these parasitic infections is given. The difference between infection and disease is explained, and the properties of an ideal drug for combatting the different diseases are described. After a short comment on the goals of the primary and secondary screening procedures the authors refer to WHO's Special Programme for Research and Training in Tropical Diseases. As to the different forms of filariasis, the most important problem is onchocerciasis due to the high rate of blindness. The existing drugs (suramin DEC) are evaluated, however, there is a need for a safe, macrofilaricidal drug. The chemotherapy of filariasis caused by W. bancrofti and B. malayi and the drugs used is also discussed. Thereafter, a survey on the chemotherapy of schistosomiasis and the drugs at hand and in development is given with special reference to praziquantel. Chemotherapy of opistorchiasis and clonorchiasis is still unsatisfactory. The problems arising from this situation are mentioned. Up to now, we have a similar situation in hydatid disease, caused by Echinococcus species. The therapy of choice is operation, however, in animal experiments it could be demonstrated that benzimidazole derivatives inhibit the growth of cysts what indicates the possibility of chemotherapy in man also. Finally, a survey is given on anthelminthic drugs for the therapy of different forms of intestinal helminthiasis with special regard to ancylostomiasis.

During an investigation of 31 sandpits in children's playgrounds in and around Frankfurt/M Toxocara eggs were detected in 27. The prevalence in areas with few or no parks (averaged 14.8 eggs 100 g-1 sand) was much higher than in districts where there was more room for the dogs to run about (5.3 eggs 100 g-1 sand). Larval development was complete in 40% of isolated Toxocara eggs after four weeks. The importance of these findings in connection with the risk, to children playing, of a possible infection (larva migrans visceralis) and preventive measures are discussed.