ABSTRACT
BACKGROUND: Hymenolepis diminuta is a cestod of rodents and rarely infects humans. Infection in humans is via ingestion of infected insects. This study was aimed to detect H. diminuta cysticercoids in red flour beetles, Tribolium castaneum, and cockroaches originated from different regions of Iran. METHODS: The red flour beetles and cockroaches were collected from local bakeries in five cities including Tehran, Ahvaz, Kazerun, and Sabzevar during 2010-2011. Some beetles and cockroaches were colonized in insectary and adults from F1 generation were fed on H. diminuta eggs. Both laboratory-infected and field-collected samples were dissected and examined for cysticercoids. Detection of H. diminuta DNA in T. castaneum beetles was performed by targeting a partial sequence of Ribosomal gene. RESULTS: Except the beetles from Ahvaz, all specimens were negative for cysticercoid by microscopy. Of the four dissected beetles from Ahvaz, one harbored 12 cysticercoids. Also, 110 (52%) of laboratory-infected beetles showed infection with an average of 12-14 larvae. None of the cockroaches was infected. Two beetles from Ahvaz, including the remainder of the microscopic positive specimen, yielded the expected amplicon in PCR assay. The H. diminuta DNA sequences generated in this study were identical and matched 97-100% with similar sequences from GenBank database. CONCLUSION: Lack of infection in the majority of beetles may reflect a low rat infestation rate in those areas, alternatively, the examined specimens might not have been the representative samples of the T. castaneum populations.
ABSTRACT
Cutaneous leishmaniasis is the most important health problem in the city of Bushehr, southwestern Iran. The objective of the study was to determine some ecological aspects of sand flies in the city during 2010-2011. Sand flies were collected monthly from outdoors and indoors by sticky traps at four selected districts of the city. They were also dissected and examined by nested-PCR for identification of the parasite during August-September of 2011. A total of 1234 adult sand flies were collected and 6 species including 3 of Genus Phlebotomus and 3 of Genus Sergentomyia were identified. Four species including P. papatasi (3.98%), P. sergenti (1.14%), S. tiberiadis (87.18%), and S. baghdadis (7.7%) were found indoors. Six species including P. papatasi (3.47%), P. sergenti (3.17%), P. alexandri (0.1%), S. tiberiadis (77.74%), S. baghdadis (15.41%), and one female of S. clydei (0.11%) were collected from outdoors. Sand flies started to appear from March and disappear at the end of January. There was only one peak in the density curve in July. The study revealed that S. tiberiadis and S. baghdadis could enter indoors which 89 and 81.8% of them were found blood-fed, respectively. Moreover, P. papatasi, S. tiberiadis, and S. baghdadis were active indoors and outdoors in most months of the year. Nested-PCR of P. papatasi females was positive against kinetoplast DNA of L. major and L. turanica and also mixed natural infections were found by L. gerbilli and L. turanica. Moreover, mixed infections by L. major and L. turanica were observed in this species. Sergentomyia clydei and S. tiberiadis were found to be negative to any DNA of Leishmania species. Phlebotomus sergenti females were found infected with DNA of L. turanica and this is the first report of natural infection and detection of the parasite from this sand fly species in worldwide.
ABSTRACT
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.
ABSTRACT
BACKGROUND: Cutaneous leishmaniasis (CL) represents the most frequent vector borne parasitoses in Iran. The objective of this study was to determine the epidemiological features of CL including human infection and the reservoir host in the city of Bushehr, Bushehr Province, Iran during 2010-2011. METHODS: Studies on human infection was carried out on 2962 school children aged 7-14 years old from 60 primary schools and among 400 households with a total population of 1568 in four infected districts of the city in December 2010. Serosity materials from patients on glass slides were collected for molecular identification of causative agent. Rodents were caught by Sherman traps and examined for identification of the parasite. RESULTS: Prevalence of scars and ulcers among the inhabitants were 5.86% and 0.12% respectively. Molecular study indicated the presence of two coexisting species: Leishmania major and L. tropica among patients. The scar rate was 1.24% but no ulcers were seen among the students. Nineteen rodents were caught and identified as Tatera indica (47.4%) and Rattus norvegicus (52.6%). Specimens from 7 T. indica and 9 R. norvegicus were examined by two techniques, microscopic examination and nested-PCR. Out of 7 T. indica, 14.3% were infected with L. major and 42.9% with L. turanica by nested-PCR. Out of 9 R. norvegicus 22.2% were infected with L. turanica and 11.1% with L. gerbilli. CONCLUSION: Based on this survey L. major and L. tropica are the causative agents of the disease among patients and T. indica plays a predominant role in the dissemination of L. major in the city.
ABSTRACT
Rats are capable to harbor various pathogens, among which certain species of zoonotic parasites are included. A long-term detection of parasite fauna of rats has sporadically been carried out in Iran. Abundance of these vertebrate pests is of great importance as regards public health issue. The present paper is focused on a digenean trematode Plagiorchis muris, obtained during a comprehensive study on rats over the decades in the country. Herein we describe this occurrence in a Rattus norvegicus in northern Tehran, with specific note on its morphological description. P. muris can infect human through consumption of infected marine food items, and has never been observed in Iran.
ABSTRACT
The aims of this study are to identify Leishmania species and compare and validate internal transcribed spacers (ITS) polymerase chain reaction (PCR) assay against parasitological methods for diagnosing cutaneous leishmaniasis (CL). We used the ITS-PCR, parasite culture, and microscopic evaluation of stained smears on 155 specimens from suspected cases of (CL) patients who referred to Mashhad Health Centers (northeast Iran). The PCR indicated the sensitivity (98.8%), correctly diagnosing 86 of the 87 confirmed positive specimens. Microscopy and parasite culture alone showed 79.3% sensitivity (69/87 positive) and 86.2% sensitivity (75/87 positive), respectively, while microscopy and culture in combination improved sensitivity totally to 100% (87/87). The results also revealed that Leishmania tropica species is dominant (96.5%) in the studied regions. This study suggests that both the parasitological techniques reliably were used for the diagnosis of CL, and the ITS-PCR assay without using RFLP analysis is useful for identifying Leishmania species in the area.
