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Due to low efficacy in the field of a local commercial product of Bacillus thuringiensis M-H-14 (Bioflash(®)), 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 LC50 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.التقييم المختبري والميداني لمستحضرين من العُصَيَّة الثورنجية M-H-14 ضد يرقات البعوض في جمهورية إيران الإسلامية، 2012.زهرا قزلباش، حسن وطن دوست، محمد رضا عبائي، أحمد رئيسي، ياور راثي، أحمد علي حنفي بجد، حسين جباري، فاطمة نيكبورفي ضوء تضاؤل الكفاءة للمنتج التجاري المحلي المستحضر من العُصية الثورنجية صمم الباحثون دراسة لتقييم كفاءته في المختبر ضمن حوض مائي زجاجي معياري، وفي ظرف ميدانية وشبه ميدانية لكل من الجرعات المستهدفة والجرعات الأعلى ضد المراحل غير الناضجة من أنواع الأنوفيلات وأنواع الباعضات. وفي الظروف المختبرية، كانت قيم الجرعة القاتلة للنصف من مستحضرات المسحوق المرطَّب جزءاً بالمليون ومن الحبيبات جزءاً بالمليون، ضد الذراري المستجيبة من الأنوفيلة الأسطفانية. وبعد تطبيق المسحوق المرطّب والحبيبات على حوض مائي بمقدار 65.1 مغ/حوض وجد الباحثون أن معدل بقاء اليرقات على قيد الحياة بعد تعرضهن لمستحضر الحبيبات كان 65.6% في اليوم 6، و54.2% في اليوم 8. أما في الأحواض الاصطناعية فإن كثافة اليرقات انخفضت إلى 38.9% بجرعة 2 غرام/متر مربع، وإلى 39.3 بجرعة 4 ميلي غرام، وإلى 65% بجرعة 8 غرام/متر مربع. وفي حقول زراعة الأرز فقد أدت جرعة مقدارها 2 كيلو غرام/هيكتار إلى انخفاض كثافة اليرقات غير الناضجة إلى 33.1% و28.6% بعد مرور 7 أيام على المعالجة. وهناك حاجة لمزيد من الدراسات حول أسباب انخفاض كفاءة مبيدات اليرقات.Évaluation en laboratoire et sur le terrain de deux formulations de Bacillus thuringiensis M-H-14 contre les larves de moustiques en République islamique d’Iran, 2012.En raison de la faible efficacité sur le terrain d’un produit commercial local de Bacillus thuringiensis M-H-14 (Bioflash

A study was done of the bionomics, insecticide susceptibility and irritability status of Anopheles culicifacies in Sistan va Baluchestan province. Sampling was performed to determine the following parameters: species identification, seasonal activity, adult and larval susceptibility tests, irritability tests, anthropophily index and sporozoite rate. An. culicfacies adults were susceptible to all tested pyrethroid insecticides. An. culicfacies started to appear indoors in late May, showing 2 peaks in June and September. Fenitrothion, cyfluthrin and permethrin had the least irritancy effect and DDT the highest. Only 2/860 females tested were infected with Plasmodium spp. (sporozoite rate: 0.25%). ELISA testing of 250 blood meals derived from night-biting collections of female mosquitoes from humans and cows revealed that only 12.5% were human-fed.

Deltamethrin plays an important role in controlling malaria vectors, and is used in indoor residual spraying and manufacture of long-lasting insecticidal mosquito nets. The residual activity of deltamethrin (K-othrine WP 5%) @ 25 mg/m(2) was studied in laboratory conditions on different surfaces.The surfaces were made artificially with different building materials such as mud, plaster, cement and wood in the laboratory. The surfaces were mounted inside petri-dishes (diam: 20 cm) and wood surface was prepared separately. The prepared surfaces were attached to the walls and deltamethrin was applied using standard Hudson pump sprayer with a discharge rate of 757 ml/ min or 0.2 gal/min. The spraying was conducted at standard rhythm as recommended by WHO. After application all the sprayed surfaces were transferred into the special wooden boxes designed for this purpose. The surfaces were maintained at laboratory conditions. The WHO's recommended bioassay kit and method was used during this study.Bioassays on Anopheles stephensi Liston showed that the persistence of deltamethrin on different surfaces (70% mortality) was around 4 months on plaster (Mortality = 77+/-6.2%), 2 months on mud (76.9+/-6.8%), 4.5 months on cement (79+/-3.2%), 4 months on wood (71.7+/-6.8%) and 4 months on filter papers (82.3+/-5.4%).The results of this study on residual effects of deltamethrin WP 5% (25 mg/m(2)) are highly concordant with two field bioassays carried out in a malarious area at south-eastern Iran. This method can be replaced by the field bioassay tests which are time consuming and costlier.

Jiroft district has subtropical climate and prone to seasonal malaria transmission with annual parasite index (API) 4.2 per 1000 in 2006. Anopheles stephensi Liston is a dominant malaria vector. The monitoring of insecticide susceptibility and irritability was conducted using discriminative dose as described by WHO.The IV instar larvae were collected from different larval breeding places and transported to the temporary insectary, fed with Bemax and then 2-3 days-old emerged and sugar-fed adults were used for susceptibility and irritability tests employing WHO methods and kits to organochlorine (OC) and pyrethroid (PY) insecticides.Mortality rates of field strain of An. stephensi were 91.3 +/- 0.14 and 90 +/- 0.47% to DDT and dieldrin, respectively at one hour exposure time but was susceptible to all pyrethroids tested. The average number of take-offs per min per adult was 2.09 +/- 0.13 for DDT, 0.581 +/- 0.05 for dieldrin, 1.85 +/- 0.08 for permethrin, 1.87 +/- 0.21 for lambda-cyhalothrin, 1.53 +/- 0.13 for cyfluthrin, and 1.23 +/- 0.1 for deltamethrin.Currently, deltamethrin is being used for indoor residual spraying against malaria vectors in the endemic areas of Iran. The findings revealed that the main malaria species is susceptible to all pyrethroids including deltamethrin, permethrin, cyfluthrin and lambda-cyhalothrin but was tolerant to DDT and dieldrin. This report and the finding are coincided with results of previous studies carried out during 1957-61 in the same area. Irritability tests to OC and PY insecticides revealed the moderate level of irritability to DDT compared to pyrethroids and dieldrin. Monitoring for possible cross-resistance between OC and PY insecticides should come into consideration for malaria control programme.

The borderline of Iran with Azerbaijan, Armenia and Turkey had been considered a malaria free region. However, in 1991, after the independence of the southern countries of the former Soviet Union, a new threat of malaria importation emerged from those countries into Iran, which was affected by serious epidemics of Plasmodium vivax malaria. Various factors can affect malaria resurgence in this region, such as socioeconomic conditions, especially the displacement of massive populations from war-stricken zones in the Republic of Azerbaijan. Accordingly, in some parts of West-Azerbaijan, East-Azerbaijan, Ardebile and Gilan provinces of Iran, several malaria foci were observed. Construction of dams, people traveling from neighboring countries to Iran, urbanization, irrigation projects, lack of malaria vector control, shortage of drug supplies are also major factors in malaria outbreaks in the region. An investigation was carried out on the bionomics of the main malaria vectors in the region. The result showed that Anopheles sacharovi plays an important role in malaria transmission and An. maculipennis and An. superpictus can be secondary vectors. Larvae were found in slow flowing water and channels with water plants. They were more abundant in June. The parity rate of blood-fed females was high in May. An. sacharovi is active from May to October with two peaks of activity, which occur in August and October. The population of this species is higher in animal shelters with a zoophicity of 95%. About 90% of bites took place in the second half of the night. A CDC light trap can also catch this species. Susceptibility testing using the WHO-recommended diagnostic doses of insecticides, revealed that this species is resistant to DDT and dieldrin, but susceptible to malathion, fenitrothion, propoxur, bendiocarb, lambdacyhalothrin, permethrin, cyfluthrin, etofenprox and deltamethrin.

The use of pyrethoid impregnated bednets is one of the main malaria vector control strategies worldwide. The objective of the present study was to evaluate the bioefficacy of bednets impregnated with various pyrethroids after repeated washings.The effectiveness of bednets impregnated with permethrin, deltamethrin, bifenthrin, etofenprox and long-lasting bednets like OlysetNet and PermaNet which were provided by WHOPES was evaluated. The tests were carried out according to the WHO-recommended methods. Malaria vector, Anopheles stephensi was exposed to impregnated bednets for 3 min and the mortality was measured after 24 h recovery period. Knockdown was measured as well.Results of three methods of bioassay tests showed that between two LLINs, PermaNet was more efficient than OlysetNet. Results of ITNs exhibited that deltamethrin and permethrin were more effective than etofenprox and bifenthrin as impregnants.Findings of this study will be useful for WHO, local authorities and people who wish to use different pyrethroid-impregnated bednets for malaria vector control.

Hormozgan Province is located in the south of Iran bordering the Persian Gulf. In this area, malaria is still considered a major health problem. In the province, eleven species of Anopheles were identified: An. pulcherrimus, An. sergenti, An. apoci, An. multicolor, An. subpictus, An. turkhudi, An. fluviatilis, An. stephensi, An. d'thali, An. superpictus, and An. culicifacies, among which only the last five species play an important role in malaria transmission. Larval habitats of malaria vectors varied from clean to brackish water, as well as sewage water, under palm trees, marshland, pools, pounds, drainage, irrigation canals, wells, and water containers. Malathion, fenitrothion, chlorpyrifos, and temephos were tested against An. stephensi, An. fluviatilis and An. d' thali larvae at diagnostic doses recommended by WHO. The results showed susceptibility to malathion, chlorpyrifos and temephos, but fenitrothion was not able to yield 100% mortality.

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.