Cryptosporidium and giardia in water in Alexandria: detection and evaluation of viability by flow cytometry and different stains

Cryptosporidium oocysts and Giardia cysts have become ubiquitous in surface waters worldwide. The number and extent of outbreaks of waterborne diseases indicate a significant risk for their possible transmission by drinking-water. Since many Egyptian cities depend on surface water as their main source of drinking water, knowledge of the prevalence of waterborne protozoa in water resources is important. The present study was designed to use flow cytometry to detect Cryptosporidium oocysts and Giardia cysts in water samples in Alexandria city in comparison with the standard staining techniques. Testing the viability of the encountered parasites was also carried out comparing flow cytometry and trypan blue vital stain. Thirty water samples were collected from water tanks from different districts of Alexandria city. Samples were subjected to staining techniques and flow cytometry. Stains used were modified Zeihl-Neelsen [MZN], safranin methylene blue [SMeB], modified trichrome, fluorescent stains [phenol auramine and acridine orange]. Viability was evaluated comparing trypan blue stain and flow cytometry using 4'-6-Diamidino-2-phenylindole immunostain [DAPI]. Flow cytometry proved to be much more sensitive than staining techniques with a sensitivity of 100% for both Cryptosporidium oocysts [30 samples] and Giardia cysts [11 samples]. Following flow cytometry, the fluorescent phenol auramine stain had the greatest sensitivity of 94.74% and 80% [18 and 4 samples, respectively]. The percent of live parasites present in each sample was always significantly higher by DAPI than trypan blue stain. The results of the present study clearly demonstrate that incorporation of flow cytometry can improve sensitivity of detection of Giardia cysts and Cryptosporidium oocysts in water samples. Although it is more expensive than the other staining methods, it is rapid, simple and accurate in estimating the quantity and viability of the parasites in each sample. Thus, flow cytometry can be recommended for detection of protozoa in water

efficacy of antihelminthic compound; clorsulon against experimental schistosoma mansoni infection

The efficacy of Clorsulon[R] [CLS] against experimental schis-tosomiasis mansoni, using Praziquantel[R] [PZQ] as a therapeutic control was evaluated. Swiss Albino mice were divided into infected non-treated control, PZQ-treated group given a single dose of 500 mg/kg four weeks post infection [PI], and infected mice treated with single, double, and triple doses of 5 mg/kg CLS per dose, one week apart starting from the 4[th] week PI. All animals were perfused for adults count. Parts of livers and intestines were examined for granulomata number and sizes. Pathological changes in hepatic parenchyma by H and E and Masson trichrome stains were also examined. Results revealed that a single treatment with PZQ caused a significant percentage reducetion [%R] of worm load [92.68%], mean egg count in liver and intestine [91.20 and 94.01% respectively], and mean size of liver granulomata was reduced [92.06%]. Regarding CLS, the worm burden was reduced proportionally with number of doses given; 87.80, 96.34 and 97.56% in single, double and triple exposures successively. Egg count in liver was decreased by 85.90, 97.01 and 96.23% respectively in treated mice. Number of intestinal granulomata was decreased by 85.28, 94.24 and 95.49% in a similar way. Size of hepatic granulomata was decreased by 89.02, 94.51 and 95.05% by 1, 2 and 3 doses consecutively. All parameters reflected non significant difference between 2 and 3 dose of CLS. The results were critically discussed

Influence of the antioxidant drug [antox] on experimental giardiasis and microsporidiosis

The effect of antioxidant [Antox] on Giardia lamblia and Microsporidium sp. in rats and mice respectively was studied. Pa-rasitologic effect was assessed by the mean parasitic count in infected animals' stool treated and non-treated, and infection intensity in stained section. Biochemical by measuring activities of lactate dehydrogenase [LDH], superoxide dismutase [SOD], malondialdehyde [MDA], myeloperoxidase [MPO] levels and cytokine induced neutrophil chemoattractant-1 [CINC-1] in intestinal homogenates in these animals as shown by cell injury, lipid peroxidation and neutrophil infiltrations. The present results showed that Antox significantly exacerbated G. lamblia and Microsporidium sp. This was manifested by a significant increase in number of G. lamblia cysts and trophozoites in stool and intestinal sections of treated infected rats. Also, microsporidian spores were significantly higher in stool of treated infected mice and infection intensity increased in the intestinal sections. The biochemical study showed a significantly higher degree of cell injury, lipid peroxidation and intestinal neutrophils accumulation in non-treated infected animals whether with G. lamblia or microsporidia. The changes reduced after treatment in giard-iasis but none in microsporidiosis. The results were tabulated photographed, and critically discussed

adjuvant effects of IL-12 and BCG on autoclaved leishmania major vaccine in experimental cutaneous leishmaniasis

Cutaneous leishmaniasis is a universal disease causing skin ulceration and deformity. A reliable vaccine remains to be a possible practical means of control. The amastigotes multiply intracellulary in macrophages provoking a cell-mediated type of immune response. IL-12 is the central cytokine of CMI. It is produced by sensitized macrophages, stimulates both Th 1 and NK cells to secrete IFN-gamma which in turn activates the intracellular killing of Leishmania in macrophages via increased oxygen radicals. This work aimed mainly at studying the adjuvant effect of IL- 12 on autoclaved L. major [ALM] vaccine, compared to that of BCG in L. major infection. The material included five groups of Swiss albino mice; the test group infected after receiving ALM + IL-12, a non-infected control group, and three other control groups infected after receiving ALM + BCG, IL-12 alone and BCG alone L. major was cultured to provide promastigotes for vaccine and infection. The measured parameters included the lesion size, type and progress; the parasite density and the level of IFN-gamma in serum. The results showed that the best protection against challenge infection was obtained by ALM + IL-12 followed by ALM + BCG. The former is recommended for use as a vaccine with regards to its proved efficacy and known safety

Influence of photon beam irradiation on lymnaea natalensis snails infected with fasciola gigantica

Lymnaea natalensis is the intermediate host of Fasciola gigantica in Egypt. The effect of photon beam irradiation on the ability of the laboratory reared L. natalensis to support the larval development of F. gigantica has been studied. 120 snails were divided into two groups: The control infected non irradiated group [GI] and the experimental infected irradiated group [GII]. The later group was subdivided into two subgroups: GIIa: snails irradiated before infection and GIIb: snails irradiated after infection. Photon beam irradiation had non significant effect on the survival rate between the all groups at the 30th day post infection. The life span, the number of infected snails and the length of the shedding period were significantly decreased in the two irradiated subgroups than the control group. The effect was more obvious on GIIb without significant difference. The number of metacercariae significantly decreased in the 2 irradiated subgroups than the control one. Also, it was significantly decreased in GIIb when compared with GIIa. So, photon beam irradiation has a great role on retarding larval development of F. gigantica inside the snail. This opens the way to a new strategy for fascioliasis control of in Egypt

Effect of schistosome mansoni infection on physiological gastrointestinal transit and contractility

The work aimed to study the effect of Schistosoma mansoni [S. mansoni] on gastrointestinal transit and contractility of the colonic muscles of two subgroups of experimental mice, in-faceted by 50 and 200 cercaria/mouse respevtively, at 8th and 12th week postinfection [PI]. In addition, the histopathologic changes in the colon, and the immunological changes of the host were studied at different durations. At 8th weeks PI, in both sub-groups, gastrointestinal transit was statistically significant decreased, in concurrent with statistically significant increase in the colonic muscle contractility compared to the controls. The colon was inflamed as shown by mucosal inflammatory infiltrates, with large size and number of schistosomal granulomas. The se-rum antigen was absent, while the serum antibody was detec-table at low titre. At 12th weeks PI, there was a more statistically significant decrease in gastro-intestinal transit, and increase in the colonic muscle contractility. The colon was still inflamed, but the granulomas were reduced in size and in number, with increase in the fibrocytes density. These alterations coincided with absence of serum antigen and increase in the antibody titre. All changes were more pronounced in the 2nd group of mice [200ceraria/mouse] than the 1st one [50cercaria/mousa]. So, intestinal schistosomiasis is associated with great structural, functional and immunological changes, related to the time coursa and the infection intensity which may be involved in the pa-thogenesis and clinical manifestations of the disease.

Congenital trichinellosis in experimentally infected mice

The present study aimed at allocating the time during pregnancy at which transpiacental transmission of Trichinella spiralis [T. spiralis] larvae took place. Swiss albino mice were infected at different durations of pregnancy; five days before mating, on gestation day zero and five days after mating. Furthermore, to study the effect of immunosuppression on transplacental transmission, half of the experimental mice were immunosuppressed using cyclophosphamide drug [Endoxan]. The percentage of infected uteri, embryos and placentas and the mean larval count were calculated on day 8 post infection [PT]. Moreover, the percentage of infected offspring and the mean larval count in their muscles were estimated on day 30 P1. The results of the present study revealed that, transpiacental transmission of T. spiralis could occur in offspring of mice when their mothers are infected before or after pregnancy. This was documented by the presence of larvae in the muscles of offspring. However, the rate of this transmission increased when the mothers are infected at late pregnancy whether they were immunosuppressed or not. The administration of the immunosuppressive drug whether before or after pregnancy increased the rate of infection and the mean larval count in both uteri of mothers and muscles of their offspring. A higher percentage of abortion was demonstrated in females infected before mating in different studied groups

utility of lactoferrin in differentiating parasitic from bacterial infections

Lactoferrin is an iron binding glycoprotein found in the 2 ry granules of PMN. In order to determine the usefulness of such marker for neutrophilic activity in differentiating cases suffering from amoebic and bacillary dysentery, Schistosoma and bacterial UTI infections, we examined stool and urine specimens using anti-lactoferrin antibodies [lactoferrin latex agglutination test: LFLA], compared with different standard gold techniques. Our results demonstrated that cases with either shigllosis or UTI revealed a high lactoferrin titer which was positively correlated with the number of PMN. In addition cases with Entamoeba histolytica or S. haematobium were characterized by relatively lower inflammatory process as expressed by mild lactoferrin titer which was also correlated with the PMN count. In addition, the findings of the present work indicated that LFLA was sensitive and specific when used alone and its sensitivity was augmented after coupling with other simple indirect methods of diagnosis. In conclusion, results described the reliability of using LFLA as a simple, rapid, sensitive method in differentiating, certain parasitic from bacterial diseases