Echinococcus granulosus sheep strain (G1) as the predominant genotype in definitive host (dogs) isolates in northeastern Iran.

Echinococcus granulosus sensu lato (E. granulosus s.l.) is a zoonotic parasite, causing cystic echinococcosis in humans. In the present study, prevalence and genotypes of E. granulosus s.l. was assessed in stools collected from 244 dogs including 138 stray and 106 domestic animals using high resolution melting curve (HRM) method. Initially, to detect taeniid eggs in feces, all samples were examined using the formalin-ether techniques. Genomic DNA was extracted from the positive samples and E. granulosus s.l. was differentiated from other Taeniidae parasites using SSU-rDNA gene and E. granulosus s.l. was analyzed for genotyping using HRM based on the cox1 gene. In total, 12.7% (31/244) of the samples were positive for Taeniidae eggs. In addition, among the positive samples, 77.4% (24/31) were positive for E. granulosus s.l.. In details, 11.3% (12/106) of the domestic dogs and 8.7% (12/138) of the stray dogs were positive for E. granulosus s.l.. The results of HRM analysis showed that all E. granulosus s.l. isolates were G1 strain. Findings of the present study indicated a considerable prevalence of E. granulosus G1 among dogs in the northeast of Iran and imply a serious risk of transmitting to humans and livestock.

Prevalence, molecular characteristics and risk factors for cryptosporidiosis among Iranian immunocompromised patients.

Cryptosporidium spp. is a major cause of diarrhea in developing countries, mainly affecting people with compromised immune systems in general and HIV-infected individuals with low CD4 + T-cell counts in particular. This infection is self-limiting in healthy persons; however, it can be severe, progressive and persistent in those who are immunocompromised. There are few published studies concerning cryptosporidiosis and Cryptosporidium genotypes in Iranian immunocompromised patients and none of them describe risk factors. This study was undertaken to identify prevalence, genotypes and risk factors for cryptosporidiosis in immunocompromised patients. Three fecal samples were obtained at two day intervals from each of the 183 patients and processed with modified Ziehl-Neelsen staining methods and 18S rRNA gene amplification and sequencing. The overall infection prevalence was 6%. Cryptosporidium parvum was identified in isolates from five HIV-infected patients, one patient who had undergone bone marrow transplantation and one with chronic lymphocytic leukemia. Cryptosporidium hominis was identified in isolates from two HIV-infected patients and two patients with acute lymphocytic leukemia. According to univariate analysis, the statistically significant factors were diarrhea (OR = 21.7, CI = 2.83-78.4, P= 0.003), CD4 + lymphocytes less than 100 cells/mm(3) (OR = 41.3, CI = 13.45-114.8, P < 0.0001), other microbial infections (OR = 7.1321.7, CI = 1.97-25.73, P = 0.006), weight loss (OR = 73.78, CI = 15.5-350, P < 0.0001), abdominal pain (OR = 10.29, CI = 2.81-37.74.4, P= 0.001), dehydration (OR = 72.1, CI = 17.6-341.5, P < 0.0001), vomiting (OR = 4.87, CI = 1.4-16.9, P= 0.015), nausea (OR = 9.4, CI = 2.38-37.2, P < 0.001), highly active antiretroviral therapy (OR = 0.089, CI = 0.01-0.8, P= 0.015) and diarrhea in household members (OR = 7.37, CI = 2.04-26.66, P= 0.001). After multivariate analysis and a backward deletion process, only < 100 CD4 + T-lymphocytes/mm(3) maintained a significant association with infection. The authors recommend that this infection should be suspected in patients with diarrhea, weight loss and dehydration in general and in diarrheal individuals with < 100 CD4 + T-lymphocytes/mm(3).