Iranian Journal of Parasitology
Volume:1 Issue: 1, Oct-Dec 2006

Malaria had being widely prevalent for a long time in Iran. Before starting any anti-malarial campaign in Iran about 60% of population was living in malaria endemic areas. In hyper-endemic areas, approximately 30 to 40% of the total mortality was due to malaria. The malariometric data, reported during 1921-1949 in the malaria surveys in some endemic areas, showed high endemicities of the disease in most parts of the country. The first malaria-training course for preliminary operations of anti-malaria campaign was started in Iran in 1945. Afterwards, in the courses conducted, mostly by the Institute of Malariology many technical personnel were trained. In 1947, for the first time DDT was used in mosquito control in a pilot study in malaria hyper-endemic villages near Tehran. It caused great reduction in malaria transmission. Anti-malarial campaign including drug prophylaxis and treatment, anti-mosquito spraying with DDT and some anti-larval control measures, carried out during 1948-1956, considerably decreased malaria infection rate in most endemic areas. In 1957, malaria eradication programme (MEP) started in Iran and up to 1980 almost interrupted malaria transmission in the north parts of the country. However, in the south parts although the infection rate considerably decreased, but due to some technical and operational problems, malaria transmission was not interrupted. Therefore, in 1980 the MEP shifted to malaria control programme (MCP) which has been continuing up to present time. From 25 species of Anopheles found in Iran, 8 species of A. stephensi, A. fluviatilis, A. culicifacies, A. pulcherimus, A. d’thali, A. superpictus, A. sacharovi and A. maculipennis are considered to be malaria vectors. The prevalent species of Plasmodia in Iran are P. falciparum and P. vivax. P. malariae is rare. The main problems, in the malaria endemic areas of the southeast parts of Iran are resistance of the main vectors to some insecticides as well as high resistance of P. falciparum to chloroquine. The total reported malaria cases in Iran from 96340 with 45% P. falciparum in 1991, gradually, decreased to 18966 with 12% P. falciparum in 2005. About 30 to 50% of malaria patients have been among foreign immigrants.

Visceral leishmaniasis (VL) is one of the most important parasitic diseases which is endemic in different parts of Iran. Serological studies were conducted by direct agglutination test (DAT) on 12144 human serum samples, collected from four geographical zones of Iran. Sero prevalence, geographical distribution, clinical signs and symptoms for human visceral leishmaniasis based on DAT for the period of 2002 through 2005 were determined. From 516 kala-azar cases detected: 50.6% were from Meshkin-shahr and Moghan districts in Ardabil Province, northwest of Iran and 49.4% were detected from other areas of Iran. In physical examination of seropositive cases, which were detected by DAT with anti-leishmanial antibodies at titers of 1: 3200 to 1: 102400, almost 50% of suspected individuals showed the classical kala-azar signs and symptoms. Predominant signs and symptoms in 233 hospitalized patients with anti-Leishmania antibodies at 1:3200 and higher, were fever (88.0%) and splenomegaly (84.5%). Statistically significant difference was found between males (58%) and females (42%) (P< 0.01). Moreover, 93.6% of the VL patients were < 5 yr of age, and 6.4% were older than 5 yr that this difference was statistically significant (P< 0.01). From 1383 serum samples collected from domestic dogs in the villages that are known as endemic foci of human leishmaniasis, 152 (11.0%) were positive by DAT (≥ 1:320). Parasitological and serological examinations that were performed in 30 wild canines showed that 10% of these animals were infected by L. infantum. L. infantum Lon49 is the principal agent of the disease in human as well as animal reservoir hosts in different parts of Iran. For the first time in Iran, L. tropica isolated from both skin lesions in the face and bone marrow aspiration in a HIV+ man who co-infected with VL as well as in an infected dog from Ardabil Province.

Fasciolosis diagnosis, due to low sensitivity of coprological diagnostic method has been challenging for a long period. In this study, Dot-ELISA, one of the simplest and the most sensitive tests in this regard, was evaluated using excretory-secretory antigens of Fasciola hepatica to diagnose human fasciolosis Three groups consisting of patients infected with fasciolosis (n= 95), patients with other parasitic diseases (n= 37) and healthy individuals (n= 40), were implicated in the test. All collected sera were tested by Dot-ELISA using excretory-secretory antigens. Optimal criteria were detected as 1.5 µg of antigen per dot, serum dilution of 1:320, and anti human IgG conjugate dilution of 1:500. The sensitivity, specificity, positive and negative predictive values were 96.8%, 96.1%, 96.8% and 96.1%, respectively. In conclusion, Dot-ELISA using excretory-secretory antigens could be regarded as a cheap, rapid, antigen and serum conservative diagnostic method in diagnosing fasciolosis.

Toxoplasmosis is a wide distributed opportunistic infection caused by Toxoplasma gondii. This was a cross-sectional study of T. gondii antibody titer, which was conducted from June 2003 to August 2004 on renal transplant recipients in Iran. A total of 551 serum samples were obtained from randomly selected population referred from different areas all over the country to Shafa Central Clinic in Tehran. Patient’s information was recorded in a questionnaire before sampling. Two samples of finger-prick blood were collected from each person and antibody titer against Toxoplasma was assessed by Indirect Fluorescence Antibody (IFA) technique on serum samples. Totally 39 cases (7.1%) of samples were positive for antibody by the titer of 1: 20 and higher. On investigation of risk factors, no significant difference was found between consumption of under-cooked meat, close contact with animals, and the source of drinking water and seropositivity rate of toxoplasmosis. The relatively low seroprevalence rate of Toxoplasma infection shows the successful approaches to awareness of transplant recipients about the potential risks of acquisition of infectious diseases due to regular administration of suppressive drugs. However, the regular surveillance through serological screening of Toxoplasma antibody in kidney transplant recipients is advisable.

In order to evaluate the effect of Berberis vulgaris extract on the experimental ulcers of cutaneous leishmaniasis (CL) on Balb/c mice, a study was undertaken over a 12 months period. Forty Balb/c mice were divided into 2 main groups A and B. Each main group in turn was divided into 5 sub groups of 4 mice and each sub group were inoculated subcutaneously by 0.1ml liquid phase culture containing promastigotes of Leishmania major. After 2-3 weeks, nodules and ulcers appeared on 37 of 40 inoculated mice. Ethanol extract of the stem and leaves as well as roots of Berberis vulgaris in different concentrations, were used topically on CL lesions of 4 sub groups A and B, respectively. Ethanol alone was used on the lesions of control mice. The surface area of lesions were measured before and 1-2 weeks after treatment. Direct Geimsa stained smear prepared 20 days after treatment. The results showed that after 2 weeks, a statistically significant decrease of ulcer size of treated mice observed, while in the control group the lesion growth continued. The examinations showed that using higher concentration of the extract caused more decrease in surface area of CL lesions on day 15 and negative direct smear on day 20. Alcoholic extract of B.vulgaris root was more effective than leaves and stem extract. Alcoholic extract of B vulgaris might be further used in animal model.

Buccal cavity as a compound ecosystem has always been ignored in parasitic infection studies; however it seems that studying on mouth and tooth prevalent parasitic infections is of great importance. In this study, from 120 patients of both sexes referred to Faculty of Dentistry, Tehran University of Medical Sciences, Iran, (2001-2002) 240 samples were taken from the plaques and calculus of depth of tooth and gum pockets. Wet-mount technique is regarded as the best and quickest diagnostic method for Trichomonas. tenax while Entamoeba. gingivalis is best diagnosed by Trichrome vitelli staining method using Bovin fixative. 41.7% and 9.2% of the cases were infected by Entamoeba. gingivalis and T.tenax, respectively, while 3.3% were infected by both parasitic protozoa. Infection to mouth amoeba was more prevalent in males at the age of 21-30 yr old while no relation was found between age/sex as to infection with Trichomonas. tenax. Accordingly, a direct relation was found between the frequency of the parasites and some factors such as periodontal tissue condition, degree of gum bleeding and inflammation, gum color and tooth decay.

Giardia lamblia is one of the most common intestinal protozoan parasites infecting human in the world. The goal of this study was searching for in-vitro effect of folic acid and cobalamin on adhesion and growth of G. lamblia as two important mechanisms in the pathogenesis in TYI-S-33 medium. G. lamblia trophozoites were obtained by in- vitro excystation procedure. Three groups of Giardia trophozoites were analyzed: control group, G.lamblia was cultured in TYI-S-33 without any vitamin, 2nd group with 0.1 µg/ml vitamin B12 or folic acid, and 3rd group with 0.5 µg/ml of vitamin B12 or folic acid. All culture media tubes incubated at 37 ºC. After 2 h of incubation, the adherence into borosilicate culture tubes, and after 24 h the growth of trophozoites were measured. The results showed that in vitamin B12 groups, the growth was increased significantly (P≤ 0.05) but the adherence decreased significantly (P≤ 0.05). Folic acid inhibited the growth rate significantly (P≤ 0.05), but it increased adherence in axenic culture significantly (P≤ 0.05). The results showed that vitamin B12 and folic acid altogether might reduce pathogenesis of G. lamblia by reducing adherence and growth, respectively.

Visceral Leishmaniasis (VL) is a sever disease that is prevalent in Iran. We report a case of VL in a 3.5 year-old boy. Prolonged fever, chill, abdominal distention, and weight loss were important symptoms. Blood count showed pancytopenia and hypohemoglobinemia. Specific anti-leishmanial antibodies were detected by serological test (IFAT, DAT) but no Leishman body was observed in bone marrow. However, a 145 bp band of KDNA belong to L. infantum was detected by PCR method. Glucantime was administered and treatment was well tolerated. This is the first report of VL from Qeshm Island in Persian Gulf.