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A 12-months study on bancroftian filariasis was carried out in the Igwun basin, Nigeria. A total of 1,418 individuals (768 males, and 650 females) were examined for microfilaremia and clinical filarial stigmata. There were 14.3% and 11.1% male and female point prevalence rates, respectively, and an overall prevalence of 12.8%. Prevalence rates and microfilarial density increased with age. The highest mff density of 35 mff/20 ml blood occurred in the 40-49 year old male individuals. Disease rates of 55.5 and 65.3% were recorded for males and females respectively. Chyluria (9.3% males, 16.7% females), hydrocele (17.8%), elephantiasis (15.9% males, 29.2% females), and enlarged groin glands (16.4% males, 19.4% females) were the major clinical signs, all associated with microfilaremia. Anopheles gambiae and Cules pipiens were the principal vectors. The estimated mean daily, weekly, and monthly per capita biting densities were 26, 161, and 753 respectively. The overall infection rate of mosquitoes was 22.3%, with a mean mff density of approximately 5 mff/mosquito. These vector parameters were indicative of active transmission in the area, and may be responsible for the high prevalence of infection, the diversity of clinical signs, and high morbidity rates.

Effect of temperature on the sporogonic cycle of Plasmodium berghei (NK 65) has been studied in vector Anopheles stephensi. To determine the optimum temperature for development of parasite, fed mosquitoes were kept at 16 +/- 1 degree C, 19 +/- 1 degree C and 26 +/- 1 degree C temperature. The temperature 19 +/- 1 degree C was found to be optimum for normal development of parasite within the vector. Sporulated oocysts were observed on the 10th day post feed and salivary glands were loaded with thousands of sporozoites on day 14. Temperature 16 +/- 1 degree C, though did not exert any deleterious effect on the morphology of parasites it delayed the development of sporozoites in the oocysts by 5 days as compared to control group. In the case of long exposure to this temperature, the sporozoites obtained from salivary glands became non-infective. Temperature 26 +/- 1 degree C was responsible for deterioration of all the stages of sporogonic cycle and it also checked the formation of sporozoites in the oocysts.

The prevalence of anti-Toxoplasma gondii antibodies in serum samples of 55 habitually aborting women, 46 women with normal pregnancies, 92 outpatient adults, and 150 University students from North Jordan was studied using the enzyme linked immunosorbent assay (ELISA). Sera from the habitually aborting group were also tested by the indirect immunofluorescent (IIF) test. No significant difference was found between the overall prevalence rates in University students, outpatient adults and women with normal pregnancies (25.3%, 22.8% and 26.1% respectively). The prevalence in habitually aborting women exceeded two times that in women with normal pregnancies or in outpatient females (58.2%, 26.1% and 25.0% respectively), and was approximately three times that in female University students (18.3%). The greatest difference in the prevalence rate between habitually aborting women and those with normal pregnancies or outpatient females was found in groups having the highest antibody level (greater than or equal to 100% of standard positive controls). A positive correlation between the results of the ELISA and those of the IIF test occurred at titres of greater than or equal to 1:40 of the latter test in habitually aborting women.

Malaria was studied in the province of Takeo, Cambodia. In the hyperendemic region of Kirivong district, 49 (46.0%) of 105 suspected patients were found to be infected, 98% of them with Plasmodium falciparum and 2.0% with P. vivax. The highest prevalence (85.7%) was recorded in the group of 15-20-year-old patients. A total of 296 patients were examined in the hospital of Takeo during one year (1983-1984) and 77 (26.0%) of them were positive. P. falciparum infection was found in 76.6% and P. vivax in 23.4% of cases. The highest prevalence (42.3%) was also in the age-group of 15-20 years. The "7-day test" was used in vivo in 15 patients in order to detect the sensitivity of P. falciparum to Fansidar. The asexual forms of parasites disappeared within 4 days, while the gametocytes survived in two patients until 7th and 8th day, respectively. The observations could not be terminated, since the two patients will fully left the hospital.

755 sheep from 41 farms in the districts of Trebisov, Michalovce, Humenné and Roznava in the East Slovakian region were investigated on the presence of antibodies to Bhanja (neutralization test) and tick-borne encephalitis (haemagglutination-inhibition test) viruses. In respective districts 2.2%, 0.4%, 1.7% and 26.7% of animals (total 5.3%) were found to be positive on Bhanja virus, 4.4%, 1.5%, 1.7% and 5.0% (total 2.6%) on tick-borne encephalitis (TBE) virus. The considerable infection rate in sheep with Bhanja virus in the district of Roznava (mean 26.7%-on one farm as high as 63.9% serologically positive animals) can be explained by the local occurrence of the tick Haemaphysalis punctata, the main vector of this virus in Europe. The serologic screening conducted indicates a low activity of natural foci of TBE in eastern Slovakia today, and confirms the existence of a natural focus of infection with Bhanja virus in the district of Roznava. Recent circulation of Bhanja virus is indicated by antibodies detected in several one-year-old sheep.

The blood picture was studied in white mice experimentally infected with Ascaris suum, Toxocara cati, and Toxascaris leonina. In mice infected with A. suum, maximum number (17%) of eosinophiles occurred on day 28 p.i. In mice infected with T. cati, the eosinophilia increased already from the first day after infection, reaching the maximum (26%) on day 21 p.i. In mice infected with T. leonina, the eosinophilia increased from day 7 to day 28 p.i. and a slightly increased number of eosinophiles persisted during the whole experiment.

Continual cultivation of Toxoplasma gondii in monolayers of HeLa cells has been performed for 6 years. The toxoplasmas were then used for serial cultivation experiments. While searching for optimal conditions for toxoplasma inoculation it was found that infected HeLa cells which were scraped off the glass were a more suitable inoculum than those released by trypsinization. The optimal dose was one zoite per 12 host cells, medium level height at adsorption 2 mm and adsorption time 90 min at 37 degrees C. The concentration of sodium bicarbonate ranging from 8.7 to 26.1 mM had no effect on the multiplication of toxoplasmas. In serial passages in Roux bottles, when the medium was changed every 2-3 days, the average yield of toxoplasmas was 6.2 X 10(6) per ml of medium (after the second change of medium, i.e., 7 days after inoculation). The toxoplasmas obtained in serial passages were suitable for purification studies, for preparation of small amounts of antigens and as an inoculum for suspension cultures.

Small mammals trapped in seven sites along the river Sava in Croatia were examined for leptospiral infection by renoculture and serological methods. Of the 1749 animals caught 702 were examined by renoculture method and 626 were tested by microagglutination-lysis. The dominant animals species caught were Microtus arvalis (672 animals) and Apodemus agrarius (552 animals). Of the 115 strains of leptospires isolated the dominant serotypes were L. grippotyphosa (40) and L. pomona (35). Five strains of L. sejroe, 9 strains of L. australis, 1 strain of L. bataviae and 25 undetermined strains were isolated, the infection rate ranging from 3 to 32%. Serologic evidence of infection was demonstrated in 91 animals, the prevalence ranging from 0 to 43% of animals depending on the trapping site. Specific agglutinins most frequently encountered were those against L. pomona (50) and L. grippotyphosa (26), though agglutinins against L. jalna (5), L. bataviae (4), L. bratislava (3) etc., were also found. A high degree if association between L. grippotyphosa and the common vole as well as between L. pomona and the field mouse was found indicating that as far as these two types of leptospires are concerned the Sava valley may be considered as their vast natural focus. It was also concluded that wild small mammals in this region of Croatia may be a source of leptospiral infection for the local population as well as for outdoor-reared domestic animals (swine, bovine).