Influence of temperature and salinity on the viability and infectivity of giardia lamblia and cryptosporidia parvum

The present work was designed to assess the effect of different degrees of temperature and salinity on the viability and infectivity of G. Lamblia and C. parvum at different storage times. The results revealed that boiling of protozoa for one minute minimized their viability to less than 1% and rendered them noninfectious, while the exposure to 4C and -4C up to seven days preserved their viability and infectivity. Whereas, it was found that salinity was effective at a high concentration [50 ppt] for a long storage time at lower concentrations

Coagglutination [Co- A]: a rapid test for the diagnosis of expenimental Trichinellosis

This work aimed to evaluate Co-A test as a new diagnostic tool in the detection of T. Spiralis antigens in both sera and urine of experimentally infected mice as compared with ELISA for the diagnosis of trichinellosis. The results obtained by Co-A test were closely correlated with those of ELISA. The results showed that both tests were capable to detect T. spiralis antigen in the urine of lightly-and heavily-infected mice only at the 30th day post infection. So, Co-A is an accurate, easy and rapid test that can be used on large scales for the diagnosis of trichinellosis

Confirmation of clinical differentiation of three Leishmania strains by computerized image analyser system

Three human strains of Leishmania, one visceral and two cutaneous leishmaniasis, were prepared from both culture and tissue of infected animals and subjected to analysis by computerized image analyzer system. The results showed differences in the morphology and nucleic acid contents of the three strains

Evidence of sexual reproduction in the protozoan parasite Leishmania of the old world

Three Leishmania strains of the old world were included in this study. Both the amastigote and promastigote stages were subjected to staining by Feulgen procedure and examined by computerized image analyzer system to determine their nuclear DNA content. Results of this study showed that in the promastigote stage, there is a single cell population; whereas in the amastigote stage, there are two populations of parasite nuclei, one with low level of DNA resembling that of the promastigote and a second population with double DNA level. The latter is formed when apparently two nuclei fused and form one with double DNA level. The data obtained in the present study indicated that Leishmania of the old world can undergo nuclear fusion, which is a strong evidence for the presence of sexual reproduction in the parasite

Detection of circulating trichinella pseudospiralis antigen by enzyme linked immunosorbent assay [ELISA]

A modified double antibody sandwich ELISA was used as a sensitive technique for demonstrating the appearance of circulating antigen of T. pseudospiralis in the sera of infected mice. The sera were tested at 5 days and 2, 4, 6, 7, 8, 10 and 12 weeks PI. The antigen was first detected on the 5th day PI; its level increased to reach the 1st peak at 4 weeks, then declined at 6 weeks. A 2nd peak was observed at 8 weeks, followed by a sharp decline to give negative OD reading at 10 weeks and increased to a moderate level at 12 weeks PI

Pathologic and ultrastructure characterization of two different strains of schistosoma mansoni

This study was performed on albino mice infected with both Egyptian and Saudi Schistosoma mansoni strains to investigate the characteristic differences between them. It was found that at the 8th week post-infection, the highest amount of egg deposition and granuloma formation was present in the liver of infected mice with the Egyptian strain, while it was highest in the small intestine of those infected with the Saudi strain, followed by the liver and the large intestine. Although no prominent histopathologic differences were detected in the cellular and tissue reactions in the resulting granulomata surrounding eggs, yet marked differences were observed in the surface topography of the tegument and distribution of papillae, pattern of ridges, microvilli and spines of both strains. These differences were more pronounced in males

effect of flubendazole on the course of trichinella spiralis infection in mice: parasitological study

This work aimed to study the effect of flubendazole against different stages of Trichinella spiralis infection in mice. Three groups of experimental animals were examined: Control group, group I [treated 3 days post-infection] and group II [treated 4 weeks post- infection]. In group I, flubendazole was shown to be a very potent agent in killing Trichinella spiralis adults and larvae, when given orally in a dose of 20 mg/kg for 5 consecutive days. This is evidenced by the significant reduction in number, length of the female and reproductive capacity as well as the absence of the muscle larvae. However, in group II, the effect of the drug although still significant yet diminished in all parameters as compared with the early treatment. These results evoked ideas for further design of other treatment and control of disease

Maternal transfer of resistance to schistosoma mansoni in offspring born to trichinella-infected mice

This study was performed to investigate the presence of maternal transfer of resistance to S. mansoni in mice born to Trichinella-infected mothers T. spiralis-born mice were infected with S. mansoni cercariae. Parasitological study was done at eight and twelve weeks post-schistosomal infection. There was a significant reduction in the number of schistosomes [44.4%], in the liver egg count [38.9%] and in the intestinal egg count [50.46%]. Histopathologically, there was a reduction in the number and size of granulomata at the different time intervals as well as acceleration in the inflammatory reaction