Investigating the frequency of free-living amoeba in water resources with emphasis on Acanthamoeba in Bandar Abbas city, Hormozgan province, Iran in 2019-2020.

OBJECTIVE: These amoebas can cause dangerous illnesses when they accidentally enter the human body, so it is necessary to determine various forms of organisms in water resources to prevent the danger they can cause and risks to human health. Currently, in Bandar Abbas, there is no sufficient information about the distribution of Acanthamoeba, and we intended to study its frequency and determine the related genotypes. RESULTS: Out of 83 water samples collected from different resources in the city, 31 plates (37.3%) were found to be positive for free-living amoebae. Of these, five were identified as Acanthamoeba (6%) by culture method and 8 (9.6%) by molecular method. Positive sample sequence analysis enabled us to distinguish two genotypes of T4 (7 cases) and T15 (1 case) in this study.

Ecological and Parasitological Study on Cerithidea cingulata (Gastropoda) in Hormoz Strait Littoral, South of Iran.

BACKGROUND: "Cerithidea cingulata" is reported from south of Iran, may act as intermediate host of Heterophyes heterophyes and cercaria dermatitis. As parasitological aspects of this brackish snail were not studied in Iran, this study was conducted in 2016, in Hormoz Strait, south of Iran. METHODS: Totally 402 snails were collected from 36 locations of three main regions in Hormozgan Province, Iran in 2015. In each location, one square meter was checked, and snails were collected for parasitological study. Snails were crashed and cercariae were studied using light microscope, in some cases natural red staining was used for better resolution. RESULTS: Mean length of snails was about 20.33 mm, width 5.57 mm. The aperture length was 5.10 and spire was 15.22. Important founded cercaria was cysticercus cercariae, echinostoma cercaria, furcocercus cercaria, furcocystocercous cercaria, gastrostomy cercaria, gymnocephalus cercaria, monostome cercaria, pelurolophocercus cercaria and xiphidiocercaria. CONCLUSION: The presence of this snail is reported from Persian Gulf to western Pacific in China. Our study showed a pattern of infection in local area and was compatible with other studies. Importance of C. cingulata as intermediate host of some medically important disease should be considered and other complementary molecular studies for exact identification of cercaria are necessary.

Heavy metal bioabsorption capacity of intestinal helminths in urban rats.

BACKGROUND: The aim of the present study was to evaluate the capability of helminths to absorb heavy metals in comparison with that of the host tissues. METHODS: We compared the concentration of cadmium (Cd) and chromium (Cr) in urban rats and in their harboring helminthes -Moniliformis moniliformis, Hymenolepis diminuta and larval stage of Taenia taenaeiformis (Cysticercus fasciolaris). The heavy metal absorption was evaluated in 1g wet weight of parasites and tissues digested in nitric acid, using Inductivity Coupled Plasma (ICP_OES). RESULTS: A higher concentration of heavy metals was revealed in the helminths than in the host tissues. Bioconcentration factor (BF= C in parasite/C in tissue) for both Cd and Cr absorption was more than 10-fold higher in M. moniliformis than in the three compared host tissues. The BF of Cd in M. moniliformis compared to the liver, kidney and muscle of the host was 9.16, 14.14 and 17.09, respectively. BF in Cr in the same parasite and the same host tissues ranged from 10.67, 7.06 and 4.6. High level of absorption in H. diminuta was significantly likewise; the individual BF of Cd and Cr in H. diminuta compared to the liver, kidney and muscle of the hosts was 4.95, 5.94 and 4.67 vs. 2.67, 11.56 and 5.59. The mean concentration of Cd and Cr in C. fasciolaris was also significantly higher than that in the rat livers (P<0.007 and P<0.004, respectively). CONCLUSION: This study claims that parasites of terrestrial animals exposed to heavy metals can be more accurate indicators than the host tissues as new environmental monitoring agents.

Spatial outline of malaria transmission in Iran.

OBJECTIVE: To conduct for modeling spatial distribution of malaria transmission in Iran. METHODS: Records of all malaria cases from the period 2008-2010 in Iran were retrieved for malaria control department, MOH&ME. Metrological data including annual rainfall, maximum and minimum temperature, relative humidity, altitude, demographic, districts border shapefiles, and NDVI images received from Iranian Climatologic Research Center. Data arranged in ArcGIS. RESULTS: 99.65% of malaria transmission cases were focused in southeast part of Iran. These transmissions had statistically correlation with altitude (650 m), maximum (30 °C), minimum (20 °C) and average temperature (25.3 °C). Statistical correlation and overall relationship between NDVI (118.81), relative humidity (⩾45%) and rainfall in southeast area was defined and explained in this study. CONCLUSIONS: According to ecological condition and mentioned cut-off points, predictive map was generated using cokriging method.

Morphometric differentiation between camel and sheep strains of Echinococcus granulosus using computer image analysis system (CIAS).

OBJECTIVE: To find importance of morphometric criterion of larval rostellar hook of Echinococcus granulosus (E. granulosus) and the easy and reliable method for distinguish sheep and camel strains in epidemiologic studies. METHODS: Larval rostellar hooks (n=1860) of 31 camel and sheep isolates in Iran, which already had been characterized by PCR, were carefully processed by computerized imagime analysis system (CIAS) and acquired data about rostellar hooks were analyzed using software SPSS. RESULTS: Measurement analysis of rostellar hooks [mean length (24.23±3.12) µ m] indicated that length of the large hook was a remarkable parameter for strain differentiation. Data analysis demonstrated that CIAS could be used as a reliable tool to distinguish camel from sheep strains with high sensitivity (95.2%) and specificity (91.5%). CONCLUSIONS: CIAS as a specific, sensitive, economic, fast, and reliable means might be used for differentiation of E. granulosus strains. Although perimeter and area were measured by digital technology, they were not shown as discriminative criterion as total hook length did.

Low-altitude outbreaks of human fascioliasis related with summer rainfall in Gilan province, Iran.

Following human fascioliasis outbreaks in 1988 and 1999 in Gilan province, northern Iran, efforts are now made to shed light on the seasonal pattern of fascioliasis transmission in this endemic area, taking into account snail host populations, climatic conditions and human cases. Populations of the intermediate host snail (Lymnaea spp.) peak in May and November, while there is a fourfold increase in the rate of human fascioliasis in February compared to that of September. Transmission is likely to occur mainly in late autumn and sporadically in late spring. Rainfall, seasonally analysed in periods of 3 years, indicates that accumulated summer rainfall may be related with the 1988 and 1999 human fascioliasis outbreaks. Although a more detailed picture, based on the analysis of further abiotic and biotic factors influencing fascioliasis transmission in this area, is required to substantiate this hypothesis, our results serve as the first step of a geographical information system project concerning the epidemiological study of fascioliasis in Iran. This local-scale study concerning the effects of climate change and natural disasters on the spread of fascioliasis aims to facilitate the understanding of what goes on at the regional scale in this respect.

Ecological study and risk mapping of visceral leishmaniasis in an endemic area of Iran based on a geographical information systems approach.

Between 1998 and 2001, a total of 1,062 human cases of visceral leishmaniasis were reported from the rural district of Meshkin-Shahr in the mountainous, north-western Iranian province of Ardabil. In the summer of 2008, a cross-sectional study of dogs was conducted in this endemic area by randomly selecting 384 animals from 21 villages and testing them serologically for leishmaniasis. Villages, in which more than 10% of investigated dogs showed anti- Leishmania titres ≥ 1/320, were considered to be high-risk environments. Regression analysis showed no statistically significant correlation between topographic conditions and the prevalence of positive cases. However, when the results were compared with past meteorological records, a statistically significant positive correlation (P = 0.007) was found between the number of infected dogs with anti-Leishmania titres ≥ 1/640 and the number of days in a year with temperatures below 0 °C. While humidity showed an inverse correlation (P = 0.009) with the anti-Leishmania titres, a positive correlation (P <0.001) was found in relation to the amount of rainfall. Mapping of the areas at risk for kala-azar in the Meshkin-Shahr district supports the impression that the low temperatures prevalent in the Ardebil province constitute an important factor influencing the distribution of leishmaniasis there.

Evaluation of pityriasis versicolor in prisoners: a cross-sectional study.

BACKGROUND: Pityriasis versicolor (PV) is a mild but recurrent superficial fungal infection of stratum corneum. Many predisposing factors such as late teen and young adulthood age, tropical and subtropical climate (and to a lesser extent temperate climate), immunosuppression, malnutrition, use of oral contraceptives, hyperhidrosis, poor hygiene and a few other factors have been proposed for this condition. AIM: Regarding these probable and possible risk factors, we felt that jail is a unique population which can be affected by this infection and therefore we decided to evaluate some aspects of this infection in this population. METHODS: In this cross-sectional study in male prisoners of Bandarabbas city, 230 prisoners were randomly selected. One hundred and five (45.67%) of them were diagnosed to be infected. They were also evaluated regarding age, duration of being imprisoned, skin color, site of lesion and its pigmentation change and any concomitant clinical manifestation such as pruritus, burning or cebure. Chi-square test or Fisher's exact test was used for data analysis. RESULTS: Mean age of infected population was 31.62 +/- 8.67 years while peak incidence of PV was in 28-32 years age group. The most common color change was hypopigmentation. No case of PV hyperpigmentation was seen. We could not also observe any association between skin color and duration of being imprisoned with the frequency of infection. CONCLUSION: There seems to be no difference between pattern of infection in the general population and prisoners' population in the aspects evaluated.

A serological study on Toxoplasma gondii infection among people in south of Tehran, Iran.

Although Toxoplasma gondii infection generally shows subclinical courses in adults, it may have severe pathologic effects on the fetus. For a survey of toxoplasmosis in Shahr-e-Rey area, south of Tehran, Iran, we conducted a serological study on 1,187 general populations using indirect fluorescent antibody (IFA) test. In this cross sectional study, cases were selected randomly by a local primary health care (PHC) system. Blood samples were collected in microcapillary tubes and sera were examined by IFA after centrifugation. It has been shown that 68.3% of cases in all age groups had IFA titer of 1 : 10 and higher, which we consider as positive cases, and the rate for 1 : 400 or over was 30.2%. There was meaningful correlation between anti-Toxoplasma antibody titers and age, sex, and occupation of subjected people (P < 0.05%). The incidence was higher in females and highest in the children age group (10-14 years old). The present study demonstrates high prevalence of Toxoplasma infection among the people in south of Tehran, Iran.