Iranian Journal of Parasitology
Volume:4 Issue: 4, Oct-Dec 2009

Echinococcosis or hydatid disease is a zoonotic infection caused by larval (metacestode) stages of cestodes belonging to the genus Echinococcus، family Taeniidae. We aimed to subclone antigen B gene in pQE-30 plasmid، its expression، and purification. We subcloned HI gene into pQE-30 expression vector. The recombinant vector was transformed into E. coli، M15 and mass cultured. The subcloned gene was expressed by IPTG. Subcloning of gene was confirmed by both PCR and enzyme digestion. Production of recombinant protein was confirmed by SDS-PAGE. Western blot analysis was carried out by both His-Tag monoclonal Ab and human serum to estimate the expressed protein in E. coli cells. Recombinant protein was purified and its specificity was proved by Western blotting. Production of this recombinant protein can increase sensitivity and specificity in serological test (ELISA).

The recently reported resistance to antimalarials contributes to making the control of ma­laria more difficult. There is a need to evaluate the current antimalaria regimens to prevent this emerging problem. The aim of this study was to determine dihydrofolate reductase-thymidylate synthase gene mu­tation (pvdhfr) regarding antifulate resistance in Plasmodium vivax. From 2007 to 2009، 117 P. vivax infected blood samples collected from two regions of Hor­mozgan Province، south of Iran were analyzed using PCR، semi-nested-PCR and RFLP methods. Eighty four isolates (71. 8 %) showed no mutation in pvdhfr gene of P. vivax known as wild type and 33 (28. 2%) of the samples revealed nine single (7. 7%)، twenty two double (18. 8%) and two (1. 7%) triple mutations. Genetic diversity was observed by molecular methods in pvdhfr gene of p. vivax in Hor­mozgan Province suggests that the antifolate falciparum malaria drug (fansidar) is proportionally affecting P. vivax dhfr mutation. Therefore، more studies to evaluate antimalarial drugs that should preferably be effective against both P. vivax and P. falciparum are recommended.

The Imo River Basin، Nigeria is endemic for onchocerciasis، bancroftian filariasis، loaiasis and mansonellosis. This study was aimed at determining the clinical manifestations of onchocerciasis in this region. A cross-sectional study was carried out in 2006 in Umuowaibu I and Ndiorji commu­nities in Okigwe Local Government Area of Imo State، Nigeria. Consenting individuals were ex­amined for various gradations of skin manifestations، subcutaneous nodules، and visual im­pair­ments by qualified medical doctors. Five categories of skin manifestations were observed، namely permanent itching، onchodermatitis، atrophy of skin، leopard skin، and sowda. A total of 1024 individuals were examined. The prevalence of the skin manifestations were permanent itching (2. 5%)، onchoder­ma­titis (3. 9%)، atrophy of the skin (5. 8%)، leopard skin (22. 1%)، and sowda (0. 1%). The preva­lence of subcutaneous nodules was 25. 3%، but 88. 9% among the oldest age group، and mostly found in lower half of body. The majority of cases of visual acuity problems (6. 8% overall prev­alence) were in the oldest age groups. Among those who were ≥ 20 years old، the prevalence of visual acuity problems was significantly higher in females than in males (χ2-test; P< 0. 05). Only two of the examined persons were observed to be blind. Clinical manifestations of onchocerciasis are perhaps more intense in the area prob­ably because of presence of endemic infections of other filarial species.

As consumption of chicken meat may be as one of the sources of human infection، this study was undertaken to determine the prevalence of T. gondii in farm chickens (Gallus gallus domesti­cus) in Shiraz، southern Iran. Two hundred and thirty one blood samples were collected from farm chickens by a cluster ran­dom sampling method and tested for toxoplasmosis by indirect fluorescent antibody technique (IFAT). The samples of the brain، heart، and liver of the chickens were tested by a Nested PCR method. The re­sults were analyzed by SPSS software using Chi-Square test and a P value <0. 05 was considered statically sig­nificant. Out of 58 seropositive chickens، 29 (1:16 in eight، 1:32 in 14، 1:64 in five and 1:128 in two birds) and out of seronegative chickens، three were enrolled in the study. The most infected tissue was liver (27 out of 29) and the lowest was the heart (16 out of 29) (α=0. 05، P=0. 002). None of the seronegative chick­ens was positive in PCR method. Only 2 out of 8 cases with a titer of 1:16 (as cut off point) were negative in PCR method whereas the remained were positive. Based on cultural and food habits in our area، the meat and viscera of chicken may be impor­tant sources of infection in human when consuming semi-cooked meats. Considering the high prevalence of toxoplasmosis in chickens، standards in chicken breeding، education of environmental health personnel and standardization for preparation and handling techniques are required by Health and Veterinary organiza­tions.

Diagnosis of cutaneous leishmaniasis (CL) is often made based on clinical manifesta­tion. Correct diagnosis and identification of the parasite are crucial for choosing the effective treat­ment and for epidemiological studies. On the other hand، determination of Leishmania species is nec­essary for designing appropriate control programs. Diagnosis by PCR is becoming a ''gold standard''. For PCR preparation، storage and shipments of specimens are necessary. In this study، Whatman filter paper (FTA Card) was used to store and transfer samples for Leishmania identification using PCR. Among the patients who had CL lesion and referred to Parasitology Laboratory of Emam Reza Hospital، Mashhad، Iran، 44 consented cases with positive results in their direct smear were se­lected. An informed consent form and a questionnaire were completed and three different types of samples (direct smear، NNN culture، and spot on FTA card) were collected. DNA extraction and PCR were carried out on three different samples from each patient. PCR results using Whatman paper samples revealed a significant difference (P<0. 0001) compared to the culture method but no significant difference was seen between PCR results using samples stored on Whatman paper and direct smears. The use of FTA cards is simple، rapid، and cost-effective، and can be readily employed for large-scale population screening، especially for regions where the specimens are to be transported from distant places to the laboratory.

Trichomonas vaginalis is a parasitic protozoan with a predilection for human urogenital tract and causative agent for vaginitis، cervicitis and urethritis in females. T. vaginalis is known as a cofactor in transmission of human immunodeficiency virus and may lead to adverse outcomes in pregnant women. The goal of this study was to determine the prevalence of T. vaginalis infection in females attending Mirzakuchak Khan Hospital، Tehran، Iran. During May 2008 to March 2009، 500 vaginal discharges samples were obtained from women attending sexual transmitted disease (STD) clinic of Mirzakuchak Khan Hospital in Tehran، Iran. The samples were examined by Dorsse culture medium and wet-mount meth­ods. The prevalence of T. vaginalis was determined using culture based method and wet-mount examinations. Sixteen positive (3. 2%) and 484 negative (96. 8%) samples for T. vaginalis were de­tected by culture based methods. The wet mount examination revealed 13 positive (2. 6%) and 487 negative (97. 4%) samples. In the above population، prevalence of trichomoniasis was es­timated as 3. 2% based on culturing method. Due to adverse outcomes of vaginal trichomoniasis and its correlation with HIV transmission، there is a great need for public education regarding implementation of personal hygienic measures and prevention of inappropriate sexual contacts.

Dog is known to act as definitive host for some parasites that cause important diseases in man and animals. The aim of the present study was to determine the prevalence of Neospora caninum and other intestinal parasites in dogs in Khorasan Razavi Province، Iran. A cross-sectional study was done concerning frequency of N. canium and other in­testinal parasites in dogs in Mashhad area. Totally، 174 fecal samples from 89 farm dogs and 85 household dogs were collected from 2006 to 2007. Fecal samples were examined for de­tecting intestinal parasites by Mini Parasep®SF faecal parasite concentrator in Department of Parasitology، Faculty of Veterinary Medicine، Ferdowsi University of Mashhad، Iran The overall prevalence of other intestinal parasites in farm dogs and household dogs were 29. 21% and 14. 11%، respectively. Seven parasites were found in farm dogs as follows: Toxocara canis 17. 9%، Taenia sp. 10. 1%، Strongyloides stercoralis 5. 6%، Hammondia Neo­spora-like oocysts (HNLO) 4. 4%، Isospora sp. 7. 8 %، Sarcocystis sp. 7. 8 % and Giardia sp. 1. 1% and four parasite in housed dogs: Toxocara. 4. 4%، Taenia sp. 3. 3 %، Isospora sp. 2. 3 % and Sarcocystis sp. 4. 7 %. The fecal samples with HNLO were examined by N. caninum -specific PCR، and two of samples were positive for N. caninum. The farm and household dogs are the source of some important zoonotic and non-zoonotic diseases in Iran.

The aim of this study was using ELISA for detection of anti-Schistosoma haemato­bium antibodies in both sera and urine of patients with urinary schistosomiasis. Thirty three sera and urine samples were collected from patients with acute schisto­somi­asis in Diyala Province، east of Iraq in 2006. Their diseases were confirmed by find­ing S. haematobium ova in urine examination. Sera and urines of 10 healthy individuals as well as 5 patients with hydatidosis and 5 patients with acute toxoplasmosis were examined as well. Sam­ples were examined for antibody detection by ELISA method. The antigens used in this study were egg and adult antigens. All positive samples (sera and urines) showed positivity by using egg antigen whereas the negative control samples were negative; only two samples with hydatidosis were positive with using serum sample whereas with urine sample only one sample was positive. In this study، the best sensitivity and specificity obtained when using urine and adult antigen. Antibody detection by using urine is a useful، simple، and sensitive method for di­agnosis of schistosomiasis.

The aim of this study was to investigate the sero-prevalence of Neospora caninum infec­tion in Camelus dromedarius; the most popular camel species in Iran. Totally، 310 serum samples were collected from camels in Isfahan Province during 2008 and tested in Shahrekord University using indirect fluorescent antibody test (IFAT) for se­rodiagnosis of anti-N. caninum IgG antibodies as a cross-sectional study. Among evaluated serum samples، 10 (3. 22%) had anti-N. caninum antibodies detectable in dilutions of 1:50 and 1:100. to rule out false positive results due to cross-reactivity of this pro­tozoan parasite with the closely related protozoan parasite Toxoplasma gondii، an IFA was also performed for T. gondii infection in dilution of 1:16 for positively reacted serum samples against N. caninum. No con­cordant infections of these two protozoan parasites were detected. Presence of anti-N. caninum antibodies in camels in Iran emphasizes the necessity of fur­ther studies to detect the role of this organism as a pathogen and possibly economic impor­tance in ca­mels population.