RESUMO
BACKGROUND & OBJECTIVES: Cutaneous leishmaniasis (CL) has been recently emerged in new foci, posing a public health problem. Increasing cases of CL have been reported during recent years from a border area between Iran and Pakistan, a previously non-endemic area. The present study was designed for epidemiological and parasitological characterization of the disease for the first time in this area. METHODS: A total of 3100 individuals from the city of Mirjaveh and its four rural districts were randomly selected and surveyed from March 2005 to February 2006. Microscopic examination, in vitro culture, mouse inoculations and species-specific kDNA-PCR assay were carried out for Leishmania detection and species identification. RESULTS: CL was endemic in an important rural district of Mirjaveh, presenting active lesions and scars in 6.6 and 9.5%, respectively. The highest rates of both active lesions and scars were found in the age group of 10 years or under with significant differences (p < 0.05) comparing to the older age groups. No association between genders and the rate of leishmaniasis was observed (p > 0.05). The most affected location was upper limb, 39.2% of ulcers and 41.7% of scars. Inoculation of the clinical isolates on Balb/c mice, led to the development of ulcers in the animals, implying that the causative parasite is Leishmania major. The PCR amplification also generated amplicons specific to L. major. CONCLUSION: It can be concluded that Mirjaveh is an endemic region of cutaneous leishmaniasis as a new focus due to the recent emergence in this border area of south-east of Iran with a major contribution of L. major, as the causative parasite species.
RESUMO
BACKGROUND AND OBJECTIVES: Kahnooj district in south of Iran is an endemic area for malaria where Anopheles stephensi (Liston) is a main malaria vector and An. dthali (Patton) a secondary vector. According to the national strategy plan on monitoring of insecticides resistance, this study was performed on susceptibility and irritability levels of An. stephensi and An. dthali to different insecticides in the district. METHODS: The susceptibility and irritability levels of field strains of An. stephensi and An. dthali at the adult and larval stages to discriminative dose of different imagicides was determined as recommended by WHO. RESULTS: Using discriminative dose and WHO criteria it was found that An. stephensi is resistant to DDT and dieldrin with 36.1 +/- 2.3 and 62.2 +/- 1.95 mortality rates, respectively; but susceptible to other insecticides. An. dthali was found to susceptible to all tested insecticides. The larvae of An. stephensi, exhibited 100% mortality for temephos and malathion, but 44 +/- 4.32 for discriminative dose of fenitrothion. The results of irritability level for DDT and pyrethroids showed that permethrin had the most irritancy effect on An. stephensi and An. dthali. DDT and deltamethrin showed the least irritancy effect against An. stephensi with 0.42 +/- 0.08 and 0.77 +/- 0.12 take-offs/min/adult, respectively, however, lambdacyhalothrin had the least irritancy effect against An. dthali with 0.096 +/- 0.02 take-offs/min/ adult. The mean number of take-offs/min/adult with permethrin showed significant difference to DDT, lambdacyhalothrin, cyfluthrin and deltamethrin. INTERPRETATION AND CONCLUSION: Pyrethroid insecticides are being used as indoor residual sprays in Iran. Based on our results, the main malaria vectors in the region are still susceptible to pyrethroid insecticides. Therefore, we propose the use of pyrethroids with low irritancy effect in rotation with carbamate insecticides in two interval seasonal peaks of malaria transmission. Biological control including larvivorous fishes, using of local made Bacillus thuringiensis and larvicides such as chlorpyrifos-methyl are the main larval control in the region. Result on larval test exhibited the susceptibility of main vectors to some larvicides, although the 100% mortality was not obtained using fenitrothion and this is postulated the use of this insecticide in agriculture pest control. Monitoring and evaluation of insecticides resistance in malaria vectors in the region could provide an essential clue for judicious use of insecticides.