Detection of G1 genotype of human cystic echinococcosis in Egypt

The first trial to detect G1 genotype in Egyptian human isolates of hydatid cysts [HC] and serum samples to approach diagnosis of cystic echinococcosis [CE] using human sera by PCR. Using strain specific primers, 27/36 confirmed CE patients [75%] showed G1 specific band in their sera at 254 bp. Specificity was 100% without detecting bands for either other parasitosis, or mass occupying lesions. Using PCR, G1 genotype was detected in 83.3% of HC samples, without significant difference between types of human isolates [pulmonary, hepatic, or multi-organ]. G1 genotype detection in human sera was in 75% of CE patients compared to 83.3% in HC samples of the same group of patients proved satisfactory, simple and safer than HCF sampling. IHAT gave sensitivity of 58.3% compared to histopathological examination of surgically removed cysts or examination of hydatid cyst fluid [HCF] for pro-toscolices [gold standards]. The specificity was 70% with false positive reactions with other parasitic infections and mass occupying lesions. PCR detection of G1 genotype in Egyptian animal hydatid cysts showed 90% in camel isolates and 80%; in sheep isolates, but pig isolates were negative. The presence of this genotype in a high percentage in camel isolates incriminated sheep strain as the source of CE camel infection. The results may give an explanation to the contradicting results of other studies that did not relay upon molecular aspects

Genotyping of human giardiasis in relation to anti - giardia secretory IgA and mucosal histopathology

Comparative study between the prevalence of pathological grading and giardia [groups I and I] genotypes revealed that out of patients having giardia genotype I, the prevalence of grade 0 was 13.16%, grade I was 21.05%, grade II was 47.37%, grade III was 13.16% and grade IV was 2.26% in comparison with 0%, 30.77%, 46.15%, 7.69% and 15.38% in genotype II [13 patients]; 10%, 40%, 20%, 20% and 10% in group III [10 patients]; 25%, 43.75%, 18.75%, 6.25% and 6.25% in mixed genotype infections group [16 patients] as well as 25%, 25%, 35.71%, 10.71% and 3.57% in undetermined infection group [28 patients] for grade 0, I, II, III and IV pathology respectively. There was no statistically significant difference regarding the prevalence of pathological grading in different giardia genotypes in Groups I and II. The means of OD of anti-giardia secretory IgA in relation to giardia genotypes in patients infected with giardia Groups I and II were significantly different, where 1.091 +/- 0.377, 1.079 +/- 0.474, 1.524 +/- 0.503, 1.292 +/- 0.472 and 1.004 +/- 0.31 groups of genotype I, II, III, mixed genotypes infection and undetermined infection group respectively], being more increased in patients infected with giardia genotype III and in mixed genotype infection

Labortary evaluation of Bacillus sphaericus recycling in mosquito larvae

After ingestion by Culex pipiens and Anopheles pharoensis 4th instar larvae, the spores of Bacillus sphaericus strain faiyoum rapidly germinated inside live mosquito midgut. Bacterial counts and electron microscopic observations on intoxicated larvae revealed that the number of viable spores rapidly decreased during the first 12 hours with a maximum between 12 and 24 hours. In cadavers, the number of heat-resistant spores quickly increased between the first and second day post-feeding. After one week, the number of spores inside the dead larvae reached approximately 20 times the number of ingested spores for both mosquito species [4 x 165 spores/larva]. Ultrathin sections of recycled spores showed the presence of a crystalline inclusion identical to that initially present in spores before ingestion. Bioassay on Cx. pipiens 4th instar larvae showed a similar toxicity between the in vivo recycled spores [LC50 = 1.1 +/- 0.3 x 105 spores/ml after 24 hours exposure] and culture-medium-grown spores of B. Sphaericus strain faiyoum [LC50 = 1.7 +/- 105 spores/ml]