Absence of asymptomatic malaria infection in endemic area of bashagard district, hormozgan province, iran.

BACKGROUND: A successful malaria elimination program calls for enough attention to parasite carriers, especially asymptomatic malaria, as well as the diagnosis and treatment of clinical cases. Asymptomatic malaria is an infection that patients do not show any symptom; thus, these patients play critical role in the concept of an elimination program. The current investigation was conducted to evaluate the presence of these cases in Bashagard District, formerly a high malaria transmission area in Hormozgan Province, Iran. METHODS: Blood samples (n = 500) were collected from symptomless individuals residing in Bashagard to evaluate Plasmodium infection by using microscopic, serological and nested-PCR techniques. RESULTS: Regarding the microscopic and nested-PCR analysis, no asymptomatic infection was detected among studied individuals. Totally, 1% of the studied population (5 of 500) had anti PvMSP-1(19)-specific IgG antibody; however, only 0.2% (1 of 500) of the individuals was seropositive to recombinant PfMSP-1(19), using ELISA. CONCLUSION: This study showed no asymptomatic malaria infection in the studied population; hence malaria elimination is feasible and can be successfully carried out in this region.

Prevalence of Toxocara Spp. eggs in Public Parks in Tehran City, Iran.

BACKGROUND: The objective of the present research was to determine the frequency of Toxocara spp. eggs in soil samples of public parks, in the city of Tehran, Iran. METHODS: A total of 600 soil samples were taken from 120 parks between Aprils to November, 2008. Soil samples were collected from 5 distinct sites in the parks. The samples were washed with saline solution and the collected sediment from each park were equally divided and examined by floatation and Petri dish methods for Toxocara eggs. RESULTS: Ten percent were contaminated with Toxocara spp. eggs. The number of observed Toxocara eggs in each microscopic field was varied from 1-3. No significant differences were observed between floatation and Petri dish methods. CONCLUSION: Our public parks showed a high risk of toxocariasis and the need for preventive studies.

Genetic variability of Blastocystis sp. isolated from symptomatic and asymptomatic individuals in Iran.

Blastocystis is an unusual enteric protozoan parasite of humans and many animals whose pathogenic potential is still controversial. To increase the understanding of the molecular epidemiology of this emerging parasite and due to its potential impact on public health, its subtypes (STs) in Iranian symptomatic and asymptomatic individuals were determined. A total of 100 Blastocystis isolates by microscopy and culture methods were obtained. DNA was extracted from the positive culture isolates, and the Blastocystis subtypes were identified using seven subtype-specific sequenced-tagged site (STS) primers. Four subtypes, ST3 as dominant (53 %), followed by ST1 (48 %), ST5 (33 %), and ST2 (7 %) were identified. In this study, ST1 in gastrointestinal patients compared to asymptomatic individuals was significantly dominant (p = 0.001). From 33 (33 %) mixed subtype infections, ST1, 3 (14 %) was significantly related to GI symptoms (p = 0.045), and eight mixed infections with three different STs, which are under reported, were also identified.

Evaluation of Recombinant SAG1 Protein for Detection of Toxoplasma gondii Specific Immunoglobulin M by ELISA Test.

BACKGROUND: Toxoplasmosis is a serious disease in immunocompromised patients and pregnant women. Differentiation of acute and chronic infection is a major challenge in serodiagnosis of the disease. Since the aim of this study was to assess the diagnostic utility of recombinant SAG1 (rec-SAG1) for the detection of Toxoplasma-specific IgM antibodies in human sera, by an enzyme-linked immunosorbent assay (ELISA). METHODS: The purified recombinant protein SAG1 was applied in house ELISA test and the ability of it in binding to specific immunoglobulin M in 30 serum samples of acute infected patients was evaluated. The results obtained by assays with the recombinant SAG1 and standard commercial assays were compared. RESULTS: The sensitivity and specificity of in house ELISA compared to a standard commercial ELISA (com-ELISA) were 80% and 90%, respectively. CONCLUSION: It was concluded that the rec-SAG1 could be an alternative marker for detection of anti Toxoplasma-specific IgM and diagnosis of acute infection.

Recombinant SAG1 Antigen to Detect Toxoplasma gondii Specific Immunoglobulin G in Human Sera by ELISA Test.

BACKGROUND: Although some serological tests for the detection of Toxoplasma gondii-specific immunoglobulin are commercially available, better diagnostic tools are needed. The aim of present study was to evaluate the usefulness of the recombinant Toxoplasma gondii SAG1 antigen for the recognition of toxoplasmosis by ELISA. METHODS: This study was conducted in Cellular and Molecular Biology Research Centers, Shahid Beheshti University, M.C., Tehran, Iran in 2008-2009. Surface antigen 1 (SAG1), a tachyzoite stage-specific protein, was subcloned into an expression vector and was subsequently transformed into BL21 (DE3) pLysS competent bacterial cells. After inducing expression of the recombinant antigen, the protein product was purified using Ni-affinity chromatography. The immunoreactivity of recombinant SAG1 (rSAG1) was analyzed by SDS-PAGE and western blotting. The reactivity of the rec-SAG1 protein was evaluated using an ELISA. RESULT: Sensitivity and specificity of the generated recombinant-ELISA (rec-ELISA) compared to a commercially available ELISA (com-ELISA) were 88.4% and 88%, respectively. CONCLUSION: Recombinant SAG1 produced in E. coli is a promising antigen that can be used in diagnostic assays for the detection of specific antibodies against T. gondii.