Laboratory and field evaluation of two formulations of Bacillus thuringiensis M-H-14 against mosquito larvae in the Islamic Republic of Iran, 2012

Due to low efficacy in the field of a local commercial product of Bacillus thuringiensis M-H-14 [Bioflash[registered sign]], a study was designed to assess its efficacy in laboratory, glass standard aquarium, semi-field and field conditions at both target and higher dosages against immature stages of Anopheles spp. and Culex spp. In laboratory conditions, the LC[50] values of wettable powder and granule formulations were 227 and 1031 ppm respectively against a susceptible strain of An. stephensi. Following application of wettable powder and granules at 56.1 mg/aquarium, the survival rates of the exposed larvae to the granule formulation were 65.6% and 54.2% on days 6 and 8 respectively. In the artificial ponds, the larval density was reduced to 38.9%, 39.3% and 65.1% at dosages of 2, 4 and 8 g/m[2] respectively. In rice fields, at a dosage of 2 kg/ha, the density of immature larvae were reduced to 33.1% and 28.6% 7-days post-treatment. Further investigations are needed for the reasons for the low efficacy of this larvicide

[Application of satellite remote sensing for tracking of arthropod vectors of diseases]

Arthropod-borne diseases are one of the major causes of human mortality. Since launch of the first meteorological satellites in 1960s, remote sensing has been increasingly implicated in the field of human health research and the data from satellites and their sensors with different spatial and temporal resolutions opened a new field of research in human health for scientists. Search engines and national/international scientific databanks were used to search keywords of remote sensing, satellite, tick, mosquito and sand fly and obtained articles were analyzed. Some ecological indices were used more in remote sensing of arthropod-borne diseases, including NDVI, SST, LST and CCD. Data of environmental factors such as temperature, relative humidity, land use/ land cover help us to detect the habitats of vectors of diseases regard to their ecology. However, the scope of applications, beyond theoretical large potentialities, appears limited both by their technical nature and the related models developed. The main problem for application of remote sensing in health science and epidemiology of diseases, is the costs of satellite images as well as the availability in the studied times to monitor a specific subject like vector or agent of the disease. Although the majority of health studies and diseases monitoring need to application of high spatial resolution images

Field efficacy of expanded polystyrene and shredded waste polystyrene beads for mosquito control in artificial pools and field trials, Islamic Republic of Iran

Concerns about traditional chemical pesticides has led to increasing research into novel mosquito control methods. This study compared the effectiveness of 2 different types of polystyrene beads for control of mosquito larvae in south-east Islamic Republic of Iran. Simulated field trials were done in artificial pools and field trials were carried out in 2 villages in an indigenous malaria area using WHO-recommended methods. Application of expanded polystyrene beads or shredded, waste polystyrene chips to pool surfaces produced a significant difference between pre-treatment and post-treatment density of mosquitoes [86% and 78% reduction respectively 2 weeks after treatment]. There was no significant difference between the efficacy of the 2 types of material. The use of polystyrene beads as a component of integrated vector management with other supportive measures could assist in the control of mosquito-borne diseases in the Islamic Republic of Iran and neighbouring countries

Malaria situation analysis and stratification in Bandar Abbas Country, Southern Iran, 2004-2008

The aim of this study was that the past five years data were collected to analyze the situation of malaria and health facilities in this area for better understanding malaria problem and to find solutions. In this retrospective study data of the last 5 years were obtained from health center of Bandar Abbas, published papers and reports, weather forecasting organization of the city and annual reports of Hormozgan official authorities. An excel databank was created and analysis was conducted using this software. According to the national health system, Bandar Abbas also has referral net work system from periphery to the district health center. The maximum and minimum Annual Parasitic Index [API] were observed in 2005 [1.31] and 2008 [0.17], respectively. The prevalence of cases in villages was more than city, except for 2008. More than 97.6% of indigenous malaria cases were caused by Plasmodium vivax, although P. falciparum, P. ovale and mix infection were also reported. Anopheles stephensi, An. dthali and An. fluviatilis are the main malaria vectors in rural area, while only the first species is distributed in the urban area. According to results and many variables including API, Bandar Abbas is divided in two strata. From the situation analysis of Bandar Abbas it is postulated that the main activities of this district could be accuracy of data, and malaria vector control

Ectoparasites of rodents captured in Bandar Abbas, Southern Iran

Rodents play important role as hot 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. 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. 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 6 ectoparasites were collected comprising flea, lice, mite and tick. Two species fleas; Xenopsylaa 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. 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 ty-phus transmission. Ticks are important due to their role in CCHF [Crimean-Cong 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

Laboratory evaluation of 3 repellents against Anopheles stephensi in the Islamic Republic of Iran

This study evaluated the repellency effect of 3 topical repellents [permethrin, DEET and neem tree extract] against 3-5 day old females of laboratory and field strains of Anopheles stephensi. Probing/biting rates on the shaved belly of white rabbits were counted. Effective dose [ED] 50 and ED95 values were calculated by probit statistic software. The results revealed ED50 values of 0.007, 0.005 and 0.191 mg/cm2 for permethrin, DEET and neem, respectively, against the field strain. The figures for the laboratory strain were 0.006, 0.007, 0.156 mg/cm2. Major heterogeneity of response was observed using DEET. Although neem was the least effective agent, extracts of locally produced neem oil offer a promising repellent against mosquito biting

Evaluation of five local formulated insecticides against German cockroach [Blattella germanica L.] in southern Iran

The German cockroach, Blattella germanica L., is a serious household and public health pest worldwide. Control of this species has been very difficult to achieve. Toxicity of cypermethrin EC10%, deltamethrin EC5%, diazinon EC0.5%, lambda-cyhalothrin EC5% and Negon_ [permethrin+propoxur oil liquid1%] commercial formulations were investigated against adult males of German cockroaches collected from four hospitals of Bandar Abbas City, southern Iran, during 2006. These insecticides have been used for cockroach control in this city. The tests were carried out only on males by the glass jar contact method recommended by the WHO. Maximum mortality rates of 20, 35, 90, and 100% were obtained after one hour contact to label-recommended doses of cypermethrin, deltamethrin, lambad-cyhalothrin, diazinon and permethrin+propoxur insecticides, respectively. KT [50] results were different from 5.68 min for permethrin+propoxur mixture to 240.37 min for cypermethrin. German cockroach showed < 80 per cent mortality using three pyrethroid insecticides. It seems that the label-recommended concentrations of these insecticides were wrong and lower than WHO advised for cockroach control. For monitoring of resistance it is recommended to do more tests using the pure active ingredient of these insecticides

Use of expanded polystyrene [EPS] and shredded waste polystyrene [SWAP] beads for control of mosquitoes

Mosquitoes transmit several diseases to human. There are several measures for control of larvae. As part of Integrated Vector Management [IVM] program, the utility of floating layers of polystyrene beads [EPS] is a potential alternative in habitats of mosquito larva. EPS beads prevent oviposition of mosquito as well as killing the immature stages by forming a tick layer on the water surface. They are cheap, environmentally safe and do not need frequent application and remain on the surface of water for long time. The objective of the current study was to asses the effectiveness of two types of polystyrene beads of [EPS] and [SWAP] for control of mosquito larvae under laboratory conditions. Anopheles stephensi and Culex quinquefasciatus were used for experimental purposes. In each tray 250 larvae of late 3rd and early 4th instars were introduced. The experiment was conducted on 4 replicates for An. stephensi, Cu. quinquefasciatus and combination of both. Emerging of adult mosquitoes were calculated every day until the end of experiments. Mortality rate and Inhibition of Emerge [IE] for Cu. quinquefasciatus, An. stephensi and combination of both species was 97.8%, 100% and 99.07%, respectively using EPS. In average, EPS was able to kill 98.9% of larvae. The figures with SWAP were 63%, 91.05% and 72.65%, respectively. The average mortality for mosquitoes was 75.57% EPS and SWAP beads can be very effective and practical for elimination of An. stephensi and Cx. quinquefasciatus under the laboratory conditions

Ecology of Anopheles dthali Patton in Bandar Abbas District, Hormozgan Province, Southern Iran

Ecology of Anopheles dthali was studied in Bandar Abbas County, where there is indigenous malaria. Anopheles dthali plays as a secondary malaria vector in the region. It is active throughout the year in mountainous area with two peaks of activity, whereas in coastal area it has one peak. There is no report of hibernation or aestivation for this species in the region. Precipitin tests on specimens from different parts showed that 15.6-20.8% were positive for human blood. This species usually rests outdoors. It has different larval habitats. Insecticides susceptibility tests on adult females exhibited susceptibility to all insecticides recommended by WHO. LT[50] for the currently used insecticide, lambda-cyhalothrin, is measured less than one minute. The irritability tests to pyrethroid insecticides, showed that permethrin and lambda-cyhalothrin had more irritancy compared to deltamethrin and cyfluthrin. Larval bioassay using malathion, chlorpyrifos, temephos and fenithrothion did not show any sing of resistance to these larvicides at the diagnostic dose. It is recommended that all the decision makers should consider the results of our study for any vector control measures in the region

sand fly fauna of an endemic focus of visceral leishmaniasis in central Iran

Visceral leishmaniasis due to Leishmania infantum is endemic in many rural areas of Iran. An investigation was carried out during April to November 2001 in Ghahan rural district of Qom Province, in order to identify the phlebotomine sand fly fauna. 971 sand flies were totally collected from outdoor and indoor resting places by sticky traps. Ten species of phlebotomine sand flies including 8 species of the genus Phlebotomus [Phlebotomus sergenti, P. major, P. alexandri, P. kandelakii, P. tobbi, P. brevis, P. halepensis, P. [Adlerius] sp] and 2 species of the genus Sergentomyia [Sergentomyia pawlowsky and S. theodori] were collected from outdoor and indoor resting-places by sticky traps. High indoor density of P. sergenti [46.9%] and P. major [40.4%] was found with the peak of activity in early July. Based on the results of the present study and also the related studies in other VL foci of Iran, P. major can be considered as the probable vector of the disease in the area

study on rodent ectoparasities in Bandar Abbas: the main economic southern seaport of Iran

Rodents are one of the main health problems in the cities, especially in coastal area. These animals make economic damages and are potential health dangers in Bandar Abbas, the main economic southern port of Iran. In this study, rodents were captured from different parts of the city, before and after a control program during 2003-2004, transferred to the laboratory, identified and examine for ecto-parasites. Totally 105 rodents demonstrating four species: Rattus rattus [3%], R. norvegicus [78%], Mus musculus [3%] and Tatera indica [16%], were captured before the control program. The most frequency was observed in Ayatollah Ghafari quarter, 10 rodents per 24 traps. After 12 months, the duration of control program, rodents were re-captured to assessment the success of control activity. In this stage 35 small mammals demonstrated four species were obtained: R. norvegicus [51.4%], R. rattus [37.1%], T.indica [8.6%] and one weasel [2.9%]. We found the most frequency in Khoon-sorkh quarter with 6 rodents per 24 traps. The identified ectoparasites were Xenopsylla buxtoni, Rhipicephalus sp,. Polyplax gerbilli, Haplopleura captiosa, Ornithonyssus bacoti, Laelaps nuttalli, Dermanyssus americanus, Dermanyssus sanguineus, Haemolaelaps glasgowi and Echinolaelaps echidninus. The number of rodents reduced to one third after control program, shows the relative success of this program [p<0.05]

subfamily Culicinae [Diptera:culicidae] in kerman province southern Iran

There are some arboviral and parasitic diseases which are transmitted by culicine mosquitoes in Iran. Three genera and eleven species of the subfamily Culicinae [Diptera: Culicidae] were collected by dipping method and identified in Kahnooj district, Kerman province, south-eastern Iran, during October and November, 2003 including; Culex [Culex] bitaeniorhynchus, Cx. [Maillotia] deserticola, Cx. [Cux.] laticinctus, Cx. [Cux.] perexiguus, Cx. [Cux.] pipiens, Cx.[Cux.] quin- quefasciatus, Cx.[Cux.] sinaiticus, Cx.[Cux.] theileri, Cx.[Cux.] tritaeniorhynchus, Culiseta [Allotheobaldia] longiareolata, and Uranotaenia [Pseudoficalbia] unguiculata. In this study, Ur.unguiculata was identified in Kerman province for the first time. Fauna and ecology of Culicinae need more investigations in this province

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