Visceral Leishmaniasis in Southeastern Iran: A Narrative Review.

BACKGROUND: Visceral leishmaniasis (VL) has strong links with poverty, substantial medical and veterinary impacts. This review aimed to focus in studies published during 1994-2016 on VL in southeastern Iran. METHODS: The present review is based on expert knowledge and historical studies published during the past 23 yr (1994-2016) on VL in southeastern Iran. In addition, related literature found in PubMed by using the keywords such as visceral leishmaniasis, kala-azar, and Leishmania infantum are included. RESULTS: Overall, 118 children aged 4.2 yr were detected as infected with human VL (HVL). The majority of the cases were from Orzoieh district (37.1%) in southwest of Kerman Province, followed by Sirjan (15.7%), Jiroft (14.8%), Kahnuj (9.3%) and to lesser extent from other areas. The male to female ratio was 1.7. The three most frequent clinical features were represented by fever (100.0%), anemia (95.0%) and splenomegaly (91.5%). Altogether, 42.0% of the VL cases developed secondary bacterial infections, the overall case-fatality rate was 3.4%, and majorities (88.0%) of the VL patients were undernourished. Overall, 733 dogs and wild canines were examined by different techniques with various seroprevalence ranges. CONCLUSION: In southeastern Iran, VL is endemic in Orzoieh district in Kerman Province. While the dogs are implicated as the main domestic reservoir of VL, wide range of wild canines can serve as a secondary potential reservoir host.

Prevalence of Toxoplasma gondii Infection among Healthy Blood Donors in Northeast of Iran.

BACKGROUND: This cross-sectional investigation aimed to evaluate the prevalence of IgM and IgG anti-Toxoplasma gondii antibodies and the associated risk factors among healthy blood donors in Khorasan Razavi Province, northeast of Iran from Nov 2014 to May 2015. METHODS: Overall, 491 serum samples from apparently healthy blood donors referred the six biggest blood centers in Razavi Khorasan, Iran, were screened for IgG and IgM anti-T. gondii antibodies by enzyme-linked immunosorbent assay (ELISA). A structured questionnaire was used to obtain information on risk factors for T. gondii infection. Nested PCR was also used to detect DNA of T. gondii in the IgM-positive samples by using of B1 and RE (Repetitive Element) as marker for amplifying fragment size of 531 bp and 164 bp in PCR method. RESULTS: Totally, 200 (40.7%) samples were seropositive for anti-T. gondii antibodies; 184 (37.5%) donors tested seropositive for only IgG antibody, 8 (1.6%) tested seropositive for both IgM and IgG and 8 (1.6%) were positive for IgM antibody alone. Several risk factors significantly related to T. gondii seropositivity in the univariate analysis at P<0.05 included age (P<0.001), and raw/half-cocked meat consumption (P=0.015). T. gondii DNA was found in all sixteen IgM-positive samples. CONCLUSION: T. gondii infection was present among healthy blood donors in northeast of Iran. Thus, it is suggested to design screening programs for preventing transfusion-transmitted toxoplasmosis.

Gentamicin-attenuated Leishmania infantum vaccine: protection of dogs against canine visceral leishmaniosis in endemic area of southeast of Iran.

An attenuated line of Leishmania infantum (L. infantum H-line) has been established by culturing promastigotes in vitro under gentamicin pressure. A vaccine trial was conducted using 103 naive dogs from a leishmaniosis non-endemic area (55 vaccinated and 48 unvaccinated) brought into an endemic area of southeast Iran. No local and/or general indications of disease were observed in the vaccinated dogs immediately after vaccination. The efficacy of the vaccine was evaluated after 24 months (4 sandfly transmission seasons) by serological, parasitological analyses and clinical examination. In western blot analysis of antibodies to L. infantum antigens, sera from 10 out of 31 (32.2%) unvaccinated dogs, but none of the sera from vaccinated dogs which were seropositive at >100, recognized the 21 kDa antigen of L. infantum wild-type (WT). Nine out of 31 (29%) unvaccinated dogs, but none of vaccinated dogs, were positive for the presence of Leishmania DNA. One out of 46 (2.2%) vaccinated dogs and 9 out of 31 (29%) unvaccinated dogs developed clinical signs of disease. These results suggest that gentamicin-attenuated L. infantum induced a significant and strong protective effect against canine visceral leishmaniosis in the endemic area.

Alteration in mononuclear cell subpopulations in dogs immunized with gentamicin-attenuated Leishmania infantum.

The impact of immunization with gentamicin-attenuated Leishmania infantum (H-line) on the immunophenotypic profile of popliteal lymph node (PLN) and peripheral blood mononuclear cells (PBMCs) of dogs was assessed by flow cytometry and immunohistochemistry. Compared with the dogs infected with L. infantum wild-type (Group WT), there was a significantly higher percentage of CD4+, CD44+ T cells and CD14+, MHC-II+ cells and a lower percentage of CD4+ CD25+ regulatory T cells in PLN of the immunized dogs with L. infantum H-line (Group H). The percentage of CD4+ and CD8+ T cells in PBMCs of immunized dogs was higher than that in dogs of Group WT. The CD4:CD8 ratio in PLN of dogs of Group H was significantly higher than that in dogs of Group WT. A significantly higher percentage of CD21+ B cells and a lower percentage of CD79b+ cells were found in PLN of the immunized dogs compared with dogs of Group WT. Immunohistochemical investigation showed no parasites in the PLN of immunized dogs whereas there were parasites in the PLN of 60% of dogs infected with L. infantum WT. In this study, the immunophenotypic profile of mononuclear cells of the immunized dogs correlates with cellular immunity.