Comparative study on the effectiveness of coumavec® and zinc phosphide in controlling zoonotic cutaneous leishmaniasis in a hyperendemic focus in central iran.

BACKGROUND: Zoonotic cutaneous leishmaniasis (ZCL) is an increasing health problems in many rural areas of Iran. The aim of this study was to introduce a new alternative rodenticide to control the reservoirs of ZCL, its effect on the vector density and the incidence of the disease in hyperendemic focus of Esfahan County, central Iran. METHODS: The study was carried out from January 2011 to January 2012. In intervention areas, rodent control operation was conducted using zinc phosphide or Coumavec®. Active case findings were done by house-to-house visits once every season during 2011-2012. To evaluate the effect of rodent control operation on the vector density, sand flies were collected twice a month using sticky traps. RESULTS: The reduction rate of rodent holes in intervention areas with Coumavec® and zinc phosphide were 48.46% and 58.15% respectively, whereas in control area results showed 6.66 folds intensification. The Incidence of ZCL significantly reduced in the treated areas. Totally, 3200 adult sand flies were collected and identified in the intervention and control areas. In the treated area with zinc phosphide, the density of Phlebotomus papatasi was higher in outdoors in contrast with the treated area by Coumavec® which the density of the sand fly was higher in indoors. CONCLUSION: Both rodenticides were effective on the incidence of ZCL and the population of the reservoirs as well. Coumavec® seems to be effective on the outdoor density of the vector. This combination of rodenticide-insecticide could be a suitable alternative for zinc phosphide while bait shyness or behavioral resistance is occurred.

Production and Purification of Anti-Rhombomys opimus Immunoglobulins.

BACKGROUND: Zoonotic cutaneous leishmaniasis (ZCL) is an increasing public health problem in some endemic regions. Horseradish peroxidase (HRP) conjugated rabbit anti-Rhombomys opimus (R. opimus) Ig is needed for immunoblotting and ELISA tests used to explore the immune response of the rodents against the sand fly saliva. In this study, the production of HRP conjugated rabbit anti-R. opimus Ig was conducted for the first time. METHODS: Rhombomys opimus Ig was purified from serum by protein G affinity chromatography column and injected into rabbit to produce anti-R. opimus Ig antibody. The titration of antibody against R. opimus Ig in rabbit serum was checked using indirect ELISA. Rabbit anti-R. opimus Ig was purified by Sepharose-4B-R. opimus Ig column. Reactivity of this antibody was assessed by indirect ELISA and was conjugated to HRP by periodate method. RESULTS: Approximately 3.5 mg Ig was purified from 1 ml R. opimus serum using protein G affinity chromatography column. The molecular weight of purified R. opimus Ig was estimated about 150 kDa by SDS-PAGE. Nearly 2.3 mg rabbit anti-R. opimus Ig was purified from 1 ml immunized rabbit serum. The purified antibody was conjugated to HRP and the optimum titer of HRP conjugated rabbit anti-R. opimus Ig was determined as 1:8000 using direct ELISA. CONCLUSION: HRP conjugated rabbit anti-Gerbil IgG has been produced by a few companies, but to our knowledge HRP conjugated rabbit anti-R. opimus Ig is not commercially available. Production of HRP conjugated rabbit anti-R. opimus Ig is considerably helpful for immunological studies of R. opimus, the main reservoir host of ZCL in Iran as well as some other countries.

Endoparasites of rodents and their zoonotic importance in germi, dashte-mogan, ardabil province, iran.

BACKGROUND: In order to verify the infectivity of rodents with endoparasites in Germi (Dashte-Mogan, Ardabil Province) the current study was undertaken. METHODS: Using live traps, 177 rodents were trapped during 2005-2007. In field laboratory, all rodents were bled prior to autopsy, frozen at -20°C, and shipped to the School of Public Health, Tehran University of Medical Sciences, Iran. In parasitological laboratory, every rodent was dissected and its different organs were examined for the presence of any parasite. Blood thick and thin smears as well as impression smears of liver and spleen were stained with Geimsa and examined microscopically. RESULTS: Two species of rodents were trapped; Meriones persicus (90.4%) and Microtus socialis (9.6%). The species of parasites found in M. persicus and their prevalences were as follows: Hymenolepis diminuta (38.8%), Hymenolepis nana (2.5%), Trichuris sp.(40.6), Mesocestoides larva (=tetrathyridium) (3.1%), Capillaria hepatica (6.9%), Moniliformis moniliformis (11.3%), Syphacia obvelata (2.5%), Taenia endothoracicus larva (0.6%), Physaloptera sp. (0.6%), Dentostomella translucida (0.6%), Heligmosomum mixtum (0.6%), Strobilocercus fasciolaris(0.6%),and Aspiculuris tetraptera (0.6%). The species of parasites found in M. socialis and their prevalences were as follows: H. diminuta (17.6%), Trichuris sp. (5.9%), Mesocestoides larva (5.9%), S. obvelata (11.8%), S. syphacia (11.8%), H. mixtum (17.6%), and Aspiculuris tetraptera (11.8%). There were no statistical differences between male and female for infectivity with parasites in either M. persicus or M. socialis. No blood or tissue protozoan parasite was found in any of the rodents examined. CONCLUSION: Among different species identified, some had zoonotic importance. Therefore, the potential health hazard of these species needs to be considered to prevent infectivity of humans.

Sand fly Surveillance within an Emerging Epidemic Focus of Cutaneous Leishmaniasis in Southeastern Iran.

BACKGROUND: Cutaneous leishmaniasis due to Leishmania major has become a hot topic in Iran. The objective of this study was to determine some ecological aspects of sand flies in the study area. METHODS: Sand flies were collected biweekly from indoors and outdoors fixed places in the selected villages, using 30 sticky paper traps from the beginning to the end of the active season of 2006 in Kerman Province, south of Iran. The flies were mounted and identified. Some blood fed and gravid female sand flies of rodent burrows and indoors were dissected and examined microscopically for natural promastigote infection of Leishmania parasite during August to September. RESULTS: In total, 2439 specimens comprising 8 species (3 Phlebotomus and 5 Sergentomyia) were identified. The most common sand fly was P. papatasi and represented 87.1% of sand flies from indoors and 57.2% from outdoors. The activity of the species extended from April to end October. There are two peaks in the density curve of this species, one in June and the second in August. Natural promastigote infection was found in P. papatasi (12.7%). CONCLUSION: Phlebotomus papatasi is considered as a probable vector among gerbils and to humans with a high percentage of promastigote infection in this new focus of cutaneous leishmaniasis. The Bahraman area which until recently was unknown as an endemic area seems now to represent a focus of zoonotic cutaneous leishmaniasis transmission in Iran.

Molecular epizootiology of rodent leishmaniasis in a hyperendemic area of iran.

BACKGROUND: Zoonotic cutaneous leishmaniasis (ZCL) is an expanding disease and public health problem in Iran. In the current study, natural Leishmania infection rate and seasonal fluctuation of the infection in Rhombomys opimus population of a hyperendemic focus of ZCL in Iran was investigated. METHODS: The study was conducted from October 2006 to October 2008 in Esfahan Province, central part of Iran. An extensive sampling of rodents using Sherman traps was done in different seasons. Nested PCR assay was used for detection and identification of Leishmania species and the results were confirmed using PCR-RFLP. RESULTS: Leishmania infection rate was 58.6% (34 of 58) using nested PCR. 44.8% of the gerbils were infected only with L. turanica and 1.7% with L. gerbilli alone. A mixed natural infection with L. major and L. turanica was seen in 12.1% of the rodents. L. major infection alone was not seen in R. opimus population in the study area. The highest and lowest Leishmania infection rates were observed in fall and spring respectively. L. turanica infection was observed throughout the year whereas mixed infections with L. major and L. turanica was not seen in spring. CONCLUSION: It is concluded that in the study area, L. major, L. gerbilli and L. turanica circulate in the population of R. opimus. Leishmania major infection usually accompanied by L. turanica in naturally infected gerbils with the highest rate in fall. It is recommended that the role of L. turanica in the epidemiology and transmission of ZCL be revisited.

Study on Ectoparasites of Rhombomys opimus, the Main Reservoir of Zoonotic Cutaneous Leishmaniasis in Endemic Foci in Iran.

BACKGROUND: Ectoparasites of mammalian hosts play an important role for transmission of diseases from the host reservoirs to human. The aim of this study was to determine the species composition and infestation parameters for parasitic arthropods associated with Rhombomys opimus. METHODS: Ectoparasites of R. opimus were collected from seven endemic district of ZCL in Iran including Shirvan and Sfaraysen in North Khorasan Province, Kalaleh in Golestan Province, Damghan and Shahrood in Semnan Province, and Badrood and Habibabad in Isfahan Province. The areas of study were mainly desert and plain. Rodents were captured using Sherman life traps during active seasons from May to November 2008. Captured rodents were transported to laboratory and their ectoparasites were picked up using brushing against the fur of the rodents. Ectoparasites were stored in 70% ethanol for their preservation and then identified based on morphological characters. RESULTS: Ectoparasites belonged to one flea species of Xenopsylla nuttalli and one mite species of Ornithonussus bacoti. The flea species with 75.3% was more common than the mite. O. bacoti might play an important role in transmission of rat mite dermatitis among R. opimus colony. CONCLUSION: Results will provide an essential clue for combating zoonotic diseases in the region.

Ectoparasites of rodents captured in bandar abbas, southern iran.

BACKGROUND: Rodents play important role as host of ectoparasites and reservoir of different zoonotic diseases. The aim of this study was to asses the infestation of commensal rodents with ectoparasites in Bandar Abbas, a port city located in the northern part of the Persian Gulf in Iran. METHODS: Rodents were captured using live traps during the study period in year 2007. After transferring the rodents to the laboratory, they were identified and then their ectoparasites were collected and mounted for species identification using appropriate systematic keys. RESULTS: A total of 77 rodents were identified including Rattus norvegicus (74%), R. rattus (16.9%), Mus musculus (7.8%) and one hamster. Among all rodents, 40.3% were found infested with ectoparasites. A total of 69 ectoparasites were collected comprising flea, lice, mite and tick. Two species of fleas; Xenopsylla cheopis and X. astia were identified with higher index of X. astia. Two genera of ticks including Hyalomma sp. and Rhipicephalus sp. were identified. Laelaps nuttalli was the only mite found. The Polyplax spinulosa was considered as lice ectoparasite. CONCLUSION: Among all arthropods collected, flea and lice had the most and the least frequency, respectively. Nearly all rodent species were infested with Xenopsylla. These fleas are important due to their role in plague and murine typhus transmission. Ticks are important due to their role in CCHF (Crimean-Congo Hemorrhagic Fever), theileriosis, babesiosis, anaplasmosis and ehrlichiosis transmission .Monitoring of ectoparaiste infestation is important for preparedness and early warning preparation for possible control of arthropod-borne diseases.

Characterization of Leishmania infection in rodents from endemic areas of the Islamic Republic of Iran

Between 1991-2000, Leishmania species were isolated and characterized by isoenzyme and molecular analysis from rodents caught in various parts of the Islamic Republic of Iran. In areas endemic for cutaneous leishmaniasis, parasites were observed by direct microscopy in smears from 18.6% of 566 specimens. L. major was isolated from 4 species: Rhombomys opimus, Meriones libycus, Tatera indica and Mer. hurrianae. L. turanica was isolated from R. opimus for the first time in this country. In endemic areas of visceral leishmaniasis, parasites were observed in liver and spleen from 13.7% of 504 rodents. Two species were positive on culture; promastigotes isolated from Mer. persicus were characterized as L. donovani zymodeme LON50 and from Mesocricetus auratus as L. infantum LON49

Epidemiological study in a new focus of cutaneous leishmaniasis in the Islamic Republic of Iran

An outbreak of cutaneous leishmaniasis [CL] in Sabzevar county prompted this study of the epidemiology and the ecology of vectors and reservoirs. Examination of 541 schoolchildren showed rates of 9.4% for scars and 5.9% for ulcers. Among 807 inhabitants of 4 villages, 10.4% had scars and 3.0% had active lesions. The most highly infected age group was 0-4 years with a rate of 5.9%. A total of 12 849 sandflies representing 7 species were collected in the study area. Leptomonad infection was found in Phlebotomus papatasi, P. caucasicus and Sergentomyia sintoni. Parasites from man, P. papatasi and Rhombomys opimus, were isolated and characterized as Leishmania major. Based on this survey, this is an epidemic of zoonotic CL, with R. opimus the main reservoir host, and P. papatasi the main vector