Phytochemistry and larvicidal activity of Eucalyptus camaldulensis against malaria vector,Anopheles stephensi

Objective:To determine phytochemistry and larvicidal activity of Eucalyptus eamaldulensis against Anopheles stephensi.Methods:The chemical compositions of the leaf essential oils were analyzed using gas chromatography/mass spectrometry（GC/MS）.The larvicidal activity of essential oils and extract of leaf were tested against 4th instar larvae of laboratory-reared Anopheles stephensi.Results:GC/MS analyses identified the presence of 28 compounds corresponding to 99.60%of the total oil.The main constituents in the leaf essential oil were 1,8-cineole（69.46%）,γ-Terpinene（15.10%）,α-Pinene（5.47%） and Globulol（2%）.The leaf extract and volatile oil exerted significant larvicidal activity with LC50 values of 89.85 and 397.75 ppm,respectively.Clear dose-response relationships were established with the highest dose of 320 ppm essential oil extract resulted almost 100%mortality in the population.Conclusions:The larvicidal properties suggest that the essential oil of plant is a potential source of valuable larvicidal compounds against malaria vector and can be used as an alternative to synthetic insecticides.

Survey of tick species parasiting domestic ruminants in Ghaemshahr county,Mazandaran province,Iran

Objective:To determine the tick species parasitizing domestic ruminants in Ghaemshahr county in Mazandaran,a Caspian province in the north of Iran.Methods:About 361 sheep, 54 goats and 10 cattle of 18 herds in several villages in Ghaemshahr were inspected for tick infestation.Separated ticks were preserved in 70% alcohol and identified.Results:About 323 ticks(207 female,116 male) were collected,the occurrence of ticks on sheep,goats and cattle were 28.3% .22.2% and 20.0% respectively.The mean number of ticks on each animal was low (3-5 ticks per animal).Rhipicephalus sanguineus,Rhipicephalus bursa.Ixodes ricinus,Boophilus annulalus,Haemaphysalis punctata and Haemaphysalis numidiana were the tick species we found.Rhipicephalus sanguineus were the most abundant species in the study area.The largest number of ticks were generally present from April to July,mostly in animal ears and tails. Ixodes,Boophilus and Haemaphysalis occurred in mountainous areas of Ghaemshahr.whereas Rhipicephalus were present in both mountains and plains of the study area.Conclusions:The result of this study is a survey of tick species from domestic animals in Iran and implication of possible prevention measures for diseases transmitted by ticks.

Evaluation of bioefficacy ofα-cypermethrin in long lasting impregnated net(Interceptor~) using analytical method

Objective:To evaluate relationship betweenα-cypermethrin residues in Interceptor~? nets by using HPTLC methods and mortality percentage in standard WHO’s method 'cone test' after repeated washings.Methods:Interceptor~? containingα-cypermethrin was provided by BASF Company.The washing procedure and bioassay tests were carried out according to the WHO-recommended methods.Malaria vector,An.stephensi was exposed to impregnated bed net for three minutes and then mortality measured after 24 hour recovery period.Chemical analysis was carried out in chemical laboratory by using high performance thin layer chromatography method.Results:Result of cone bioassay method showed that washing reduced the efficacy of Interceptor~? bed net from 100%in unwashed nets to 15%at 20 washes.After 20 washes,nets contain(61.2±2.8) mg/m^2 resulting 15%mortality in cone test.Killing activity was reduced when nets were washed.Conclusions:Results will provide an essential clue for monitoring and evaluation of bioefficacy of any long lasting impregnated bed net for quality control.Findings of this study will be useful for WHO.local investigators and people who wish to use pyrethroid-impregnated bed nets for malaria vector control.

Demonstration of malaria situation analysis,stratification and planning in Minab District,southern Iran

Objective:To demonstrate malaria situation analysis,stratification and planning for an endemic area in southern Iran.Methods:Data on health system,population,meteorological parameters, malaria cases,anopheline vectors,and control activities during 2005-2007 was obtained from Minab Health Center,Minab Meteorological Station and published documents about malaria elements in the study area.A datasheet was created in excel 2003 for analysis.Results:There were 644 health staff working in Minab District including 99 health staff in malaria control program.The health facilities are distributed as follow:1 hospital with 96 beds,23 health centers including private centers(10 in Minab city and 13 in rural area of Minab District) and 119 health houses in rural areas of Minab District.Anopheles stephensi was the dominant species in Minab District,however,Anopheles dthali,Anopheles superpictus,Anopheles fluviatilis,Anopheles multicolor,Anopheles pulcherrimus and Anopheles turkhudi can also be found in the area. Anopheles stephensi was reported susceptible to malathion,propoxur,primphos-methyl,lambdacyhalothrin permethrin and deltamethrin,and resistant to DDT and dieldrin in the area.During the study period a total of 10 665 positive cases were reported,mainly due to local transmission (99.6%).Plasmodium vivax was the main causative agent followed by Plasmodium falciparum. There were reports about drug resistance of Plasmodium falciparum in the area.Conclusions: Using different parameters,Minab was classified into 3 strata.A plan was designed based on described goal,objectives and targets.The approaches of this plan were categorized into:health education,early detection and correct treatment,and vector control.Main constraints of these approaches are population movement between Iran,Pakistan and Afghanistan;vector control challenges at district,inadequate skilled medical staff in malaria case management and weak inter-sectorial coordination for malaria control,especially in urban areas.

Crimean—Congo hemorrhagic fever:a molecular survey on hard ticks(Ixodidae) in Yazd province,Iran

Objective:To determine the rate of Crimean-Congo hemorrhagic fever virus(CCHFV) infection in hard ticks(Ixodidae) in Yazd province of Iran.Methods:A molecular survey on hard ticks (Ixodidae) was conducted in Yazd province during 2008 -2009.A total of 140 hard ticks(three genera and 7 species) were collected from randomly selected villages and were exanimate for presence of CCHFV reverse transcription-polymerase chain reaction(RT-PCR) method.Results: CCHFV genome was found in 5.71%of hard ticks.All positive ticks were from Hyalomma genus. Positive ticks including:Hyalomma dromedarii,Hyalomma marginatum,Hyalomma anatolicum, Hyalomma detritum,Hyalomma asiaticum.We were not able to find virus in in Rhipicephalus sanguineus and Dermacentor marginatus.Results exhibited that Hyalomma is the main vector in the study area.Conclusions:Due to the presence of virus in 24 provinces’ out of 31,we recommend the use of acaricides and repellent to prevent disease transmission among humans. Greta care should be taken by the people who are working in slaughter houses.

Larvicidal activity of essential oil and methanol extract of Nepeta menthoides against malaria vector Anopheles stephensi

Objective:To investigate the larvicidai activity of essential oil and methanol extract of the Nepeta menthoides（N.menthoides） against main malaria vector,Anopheles stephensi（An. stephensi）.Methods:The essential oil of planl was obtained by Clevenger type apparatus and the methanol extract was supplied with Percolation method,larvicidai activity was tested by WHO method.Twenty five fourth-instar larvae of An.stephensi were used in the larvicidai assay and four replicates were tested for each concentration.Five different concentrations of the oil and extract were tested for calculation of LC50 and LC50 values.Results:The LC50 and LC90 values were determined by probit analysis.IC50 was 69.5 and 234.3 ppm and LC50 was 175.5 and 419.9 ppm for the extract and essential oil respectively.Conclusions:According to the results of this study methanolic extract of plant exhibited more larvicidai activity than essential oil.This could be useful for investigation of new natural larvicidai compounds.

Ectoparasites of lesser mouse eared bat,Myotis blythii from Kermanshah Iran

Objective:To identify the ectoparasits of lesser mouse eared bat,Myotis blythii inside the MahiDasth cave in Kermanshah province,Iran.Methods:A total of 30 lasser mouse eared bat(Myotis blythii) in a cave close to Kermanshah city were hunted with special net and were transported to the laboratory.After anesthetizing by chloroform,ectoparasites from these bats were removed and identified.Results:The ectoparasites include flies,ticks and mites.The 39 identified flies belonged to two families including Strebilidae(7.7%) and Nyctmbiidae(92.3%).A total number of 5 ticks of larval,nymphal and adult stages of Ixodes vespertilionis and 18 mites from Spiturnicidae family were identified.Conclusions:The result of this study is a clue for the identification of ectoparasites from bats and implication of possible prevention measures for diseases transmitted by ectoparasites.

Evaluation of biological control agents for mosquitoes control in artificial breeding places

Objective:To evaluate the entomological impact of chlorpyrifos-methyl,Bacillus thuringiensis, and Gambusia affinis on mosquitoes control in artificial breeding places.Methods:A Latin square design with 4 replicates was performed in order to evaluate the efficacy of chlorpyrifosmethyl, Bacillus thuringiensis,and Gambusia affinis on larva.The larvicide was applied at the dosage of 100 mg a.h/ha,Bacillus thuringiensis at the recommended dosage and 10 fishes per m^2 were applied at 1×1 m^2 artificial breeding sites.The larval densities for both anopheline and culicine were counted according to larvae /10 dippers prior and 24 h after application.Results: All three control agents are effective for mosquito density reduction,and the difference between the three agents and the control is significant(P【0.05).There is also significant difference among chlorpyrifos-methyl,Bacillus thuringiensis and Gambusia affinis.Bacillus thuringiensis exhibited more reduction on mosquito larval density than fish and larvicide(P【0.05).Conclusions: Bacillus thuringiensis in comparison with two other agents is the appropriate method for larviciding in the breeding places.Although long term assessing for biological activities as well as monitoring and mapping of resistance is required.

Malaria stratification in a malarious area,a field exercise

Objective:To conducted a spatial analysis for stratification of priority malaria control areas in Kahnuj County,as part of field exercise.Methods:Information of Health Centers of Kahnuj County has been used for stratification retrospectively.A knowledge,attitudes and practices(KAP) study was arranged to provide preliminary information about the knowledge,attitude and practice related to malaria in the area.Results:Numbers of malaria cases has been decreased in year 2008.There were five important vectors of malaria in this region including:Anopheles stephensi (An.stephensi),Anopheles dthali(An.dthali).Anopheles superpictus(An.superpictus),Anophels culicifacies(An.culicifacies),and Anopheles Jluviatilis(An.Jluviatilis),but majority of malaria cases in this county was related to Plasmodium vivax(P.vivax).Educational levels of community were 38% ,20% ,10% and 32% for illiterate,primary,secondary and university levels,respectively. KAP study revealed that about 37% of people have got malaria at least once and only 27% of people knew that mosquito is the vector of malaria.Conclusions:Malaria in Kahnuj represents a real threat.Transmission occurs in city center.An.stephensi can be suspected for the first peak of malaria cases in late spring in Kahnuj city.An.jluviatilis has a relatively high density in autumn while two malaria cases due to P.falciparum were reported in 2008.Based on KAP study,the knowledge of respondents seems good but the attitude and practice is low.According to the data such as API,main malaria vector,transmission rate,and foreign migrants,the Kahnuj County has been spatially divided into three strata based on various characteristics.The authorities should implement all the interventions based on stratification.

Bioassay evaluation on the efficacy of a-cypermethrin impregnated into long lasting insecticide treated nets using Anopheles stephensi

Objective:To evaluate the bioefficacy ofα-cypermethrin impregnated into long lasting insecticide treated nets(LLITNs- INTERCEPTOR?) against main malaria vector,Anopheles stephensi（An.stephensi）.Methods:The effectiveness of bed net impregnated withα-cypermethrin(INTERCEPTOR?) with washing was evaluated.The washing procedure and bioassay tests were carried out according to the WHO-recommended methods.Malaria vector, An.stephensi was exposed to impregnated bed net for three minutes and then mortality measured after 24 h recovery period.Knockdown was also measured according to the logarithmic times. Results:Result of cone bioassay method showed that bioefficacy ofα-cypermethrin decreased from 100%in unwashed to 15%in 20 washes.KT50 was measure as one minute in one wash and increased to 40 min in 20 washes.Discussion:Findings of this study provide guideline for malaria vector control authorities and people using pyrethroid-impregnated bed nets.