Observations on besnoitiosis in Virginia opossum (Didelphis virginiana) from Michigan, USA.

Besnoitia tissue cysts were found in five naturally-infected adult opossums (Didelphis virginiana) from Michigan. Details of the microscopy, histopathology, ultra-structure, and genetic features of the cysts were studied to identify their species-specific traits. The materials were differentiated phenotypically from cysts of other Besnoitia spp. by difference in size, pattern of tissue distribution, morphology of pellicle and nucleus, number of micronemes and rhoptries, amount of lipids and amylopectin, and presence of enigmatic bodies. Morphometric variations identified the tissue cysts and the pathologic changes in opossums host to be due to B. darlingi. The data were proved by phylogenetic analysis based on DNA sequences of the first internal transcribed spacer of nuclear rDNA. Cluster analysis showed that B. darlingi was distinct from all other Besnoitia spp. as two distinct phylogenetic clades: I- included Besnoitia spp. described from opossum (B. darlingi), sheep (B. jellisoni), rodent (B. akadoni) and rabbit (B. oryctofelisi) and clade II- encompassed parasites described from cattle (B. besnoiti), equids (B. bennetti) and reindeer (B. tarandi). The genetic attributed particular to the genus Besnoitia complemented the morphologica features and lead to accurate delimitation of Besnoitia species.

Correlation of ELISA copro-antigen and oocysts count to the severity of cryptosporidiosis parvum in children.

A total of one thousand and fifty (1050) young children from Mansoura Pediatric Hospital, July 2005 to July 2006 were examined for cryptosporidiosis. Detailed history was taken from each participant, stool examination by direct smear, Formalin-ether sedimentation, Sheather's floatation, modified Ziehl-Nel-seen (MZN) stain, Cryptospordium oocysts count, coproantigen detection by ELISA. Other infections were excluded. Out of 1050 children examined, cryptosporidial oocysts were detected in 90 cases by modified Zeihl Nelseen (MZN) stain, and copro-antigen ELISA added another 10 cases. There was a significant difference between age group (1-2 years), rural locality, nutrition status, and diarrhea regarding Cryptosporidium infection. There was highly significant difference in malnourished children regarding Cryptosporidium oocysts and ELISA-OD. There is a significant positive correlation between oocysts count, ELISA-OD and malnutrition. Only diarrhea had a highly significant difference in relation to other symptoms in both mean oocysts count and ELISA-OD. There was highly significant positive correlation between symptoms, oocysts count and ELISA-OD.