Journal of Arthropod-Borne Diseases
Volume:1 Issue: 2, Dec 2007

In Southeast Asia, Aedes aegypti (L.) has been incriminated as principal vector of dengue viruses and Ae. albopictus as the secondary vector of dengue fever. Therefore, the aim of this study was to investigate the effectiveness of three for-mula tions of pyrethrin derived from Tanacetum cinerariaefolium against the dengue/dengue haemorrhagic fever vectors Aedes aegypti and Ae. albopictus in the laboratory. The testings employed 2 methodologies: the WHO Larval Bioassay and WHO Adult Bioassay. The results showed that all the three pyrethrin formulations had larvicidal and adulticidal activi-ties. The impact of the sublethal doses of pyrethrin formulations on Aedes spp. larvae resulted in 4-6% of alive adult emergence compared to 90% of Ae. aegypti emerging adults and 96% Ae. albopictus alive adult emergence in the control. The impact of sublethal doses of the pyrethrin formulations caused very low fecundity on both Aedes spp. compared to the control (P< 0.05).

Accumulations of large quantities of wastes (manure, used litter, dead birds) which are excellent medium for fly-larvae over poultry houses provide breeding places for different groups of fly pests, with house-flies being the dominant species. This project is a comparative lab study. In this research project the larvicidal effects of cyromazine and triflumuron were studied as two Insect Growth Regulators (IGRs) to reduce the fly population using oral application. Both IGRs had a signifi-cant effect on larval mortality compared with their controls among the concentrations (P< 0.01, Fisher''s LSD with Bonf-feroni correction) including a dose-dependent relationship. Comparisons among LC50 and LC90 values, using fiducial limits, showed that cyromazine was significantly more toxic to the larvae of the two strains than triflumuron. It is concluded that cyromazine should be used in a larvicidal programme to control house-fly rather than triflumuron.

Tick-borne diseases such as relapsing fever and Crimean-Congo Hemorrhagic Fever (CCHF) are of public health impor tance in Iran. There are 471 reported cases of relapsing fever in 2003, according to the Ministry of Health of Iran.The num ber of cases has been increased in recent years. Its distribution is more or less prevalent in different parts of Iran. The aim of this study was to find out the fauna and natural infection of soft ticks with Borrelia in Qazvin Province, during their sea sonal activity. The province covers 15821 km² between 48-45 to 50-50 east of Greenwich Meridian of longitude and 35-37 to 36-45 north latitude of the equator. For this purpose a field study was carried out in the region. A total of 54 villages from 19 districts were selected ran domly and ticks were collected from their habitats according to the standard method. A total of 3197 Argasidae ticks were collected from human dwellings, poultry and animal shelters. They belonged to Argas and Or nithodoros genera which 36.8% were Argas persicus, 4% A. reflexus, 6.4% O. canestrini, 45.5% O. lahorensis and 7.3% O. tholozani. It should be noted that 12 ticks of O. erraticus were collected from 12 rodents borrows. We found that 8.82 % of O. tholozani ticks were infected with Borrelia persica and half of the O. erraticus were infected with Borrelia microti. All the people who are in volved with veterinary activities should be aware of disease transmission by the ticks. In the endemic area of the disease tick control is recommended.

Blister beetles (Coleoptera: Meloidae) are the main natural source of cantharidin, but the compound titre is depended on several factors including, age, sex and mating status of the insects. In order to eliminate such uncertainty factors in physio logical and chemical studies deuterium labelled cantharidin (D2C) with no natural abundance is normally introduced into the beetles'' body to use it as a model for studying the cantharidin behaviour in vivo. Experiments were achieved on Mylabris quadripunctata (Col.: Meloidae) from Southern France and the beetles were exposed to an artificial diet containing a de fined amount of D2C. On the other hand, because of the high similarity between the two compounds they cannot be well quantified by gas chromatography. In order to remove the burden, MRM technique was used for the first time which could successfully create well-defined cantharidin and D2C peaks and hence a precise measurement. MRM technique was exam ined using a GC-MS Varian Saturn which collected MS/MS data of more than one compound in the same time window of the chromatogram. It is especially useful when coeluting compounds have different parent ions, i.e. m/z 84 for D2C (coelut ing isotopically-labelled compound) and m/z 82 for cantharidin (beetle-originated compound). Using the routine GC-MS runs, measurement accuracy may be significantly reduced because the D2C peak is covered by the cantharidin huge peak while MRM could reveal the two coincided peaks of cantharidin and D2C. Therefore MRM is hereby introduced as the method of choice to separate cantharidin from D2C with high sensitivity and thus provide a precise base of quantitation.

In order to study the mosquito (Diptera: Culicidae) fauna of East Azerbaijan Province, some samplings were carried out by dipping method for the larvae and hand catch, night biting catch, total catch, and shelter pit collection as well as using window trap for the adults during June, July, and August 2004 plus July and August 2005. In total, 1305 adult mosquitoes and 603 larvae were collected. Seven genera and 15 species were identified in the prov ince including; Anopheles claviger, An. hyrcanus, An. maculipennis s.l., An. pseudopictus, An. sacharovi, An. superpictus, Aedes vexans, Coquillettidia richiardii, Cx. pipiens, Cx. theileri, Cx. tritaeniorhynchus, Culiseta longiareolata, Cs. subo chrea, Ochlerotatus caspius s.l., and Uranotaenia unguiculata. An. maculipennis complex, Cx. pipiens, and Cx. theileri were the most prevalent and widely dis tributed species. An. pseudopictus, Ae. vexans, and Cq. richiardii are reported for the first time in East Azerbaijan Province and a checklist for the mosquitoes of the province is also presented. Among the mosquitoes of the province, there are many potential vectors of human and domesticated animal pathogens that their ecology needs to be studied extensively.

Following annual report of new cases of cutaneous leishmaniasis from different areas of Kuhpayeh district, Esfahan County, an investigation was carried out on some ecological aspects of Phlebotomine sand flies during 2000-2002. Sand flies were collected biweekly from outdoor and indoor resting places with the aid of 30 sticky traps from the be ginning to the end of the active season. Female sand flies from rodent burrows were dissected and examined for the presence of pro-mastigote infection. Blood meals of engorged sand flies were identified by ELISA method. Totally, 4993 sand flies were collected and identified. The following species were found indoors: P. papatasi, P. ser genti, P. caucasicus, P. mongo len sis, P. al exandri, P. ansarii, P. major, P. kandelakii, S. sintoni, and the subsequent species were found outdoors: P. pa patasi, P ser genti, P. caucasicus, P. mongolensis, P. ansarii, P. major, S. sintoni, S. dentata, S. pawlowskyi.‍ The sand flies active season began from May till October in this region. Natural promastigote infections observed in 1.06% of P. papatasi and also in one out of four of P. caucasicus. The human and rodent blood indices in P. papatasi were 61.9% and 20.69%, respectively. It seems that P. papatasi is the probable vector among rodents and also transmit Leishmania major, the causative agent of zoonotic cutaneous leishmaniasis to man, and P. caucasicus transmit the agent of the disease among rodents.

The current study was conducted to investigate the duration of fipronil and imidacloprid gel baits toxicity against Ger-man cockroach strains in Iran during 2003-2004. In order to conduct this study, nine German cockroach strains were used. Newly emerged adult male German cockroaches starved for one scotophase (12 h), and ingested fipronil and imidacloprid gel baits for 2 h. After the given time was over, the bait was removed and replaced with mouse pellet. Mortality was re-corded at 12 intervals for 144 h (6 days). Mortality data of the replicates were pooled and was tested using probit analysis. Both gel baits were toxic to adult male German cockroaches. In the ingested bait method, the susceptible strain showed LT50 of 47.1 and 11.3 h for fipronil and imidacloprid gel baits, respectively, and the average LT90 was 74.2 and 19.3 h, respec tively. LT50 of the feral German cockroach strains varied 14.9 h from 30.5 to 45.4 h and 4.4 h from 12.4 to 16.8 h for fipronil and imidacloprid gel baits, respectively. All German cockroach strains showed a similar susceptibility to fipronil and imidacloprid gel baits, compared with the susceptible laboratory strain. The steep slopes of ingested bait mortality curves indicated that the feral German cockroach strains were homogenous to fipronil and imidacloprid ingested gel baits. These results suggest that fipronil and imidacloprid gel baits appear to have considerable potential as a bait for insecticide-resistant strains of German cockroach.

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 phle botomine sand flies including 8 species of the genus Phlebotomus (Phlebotomus sergenti, P. major, P. alexandri, P. kande lakii, 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.

Here we describe a case of ophthalmomyiasis in a male patient with basal cell carcinoma. During the operation several live and motile maggots were removed from the lesion. Preliminary examination on the larvae confirmed their affiliation to the genus Sarcophaga (Diptera: Sarcophagidae).This genus is widely distributed throughout the world and species are very difficult to identify. The authors made at tempt to approach species identification by rearing larvae to the adult flesh flies, but due to shortage of adult male specimen, reliable diagnosis in the level of species was not obtained. Possible interaction between ocular myiasis and malignancy concerning the case has not been addressed in this paper.