High Performance Thin Layer Chromatography Analysis of Deltamethrin Residue on the Impregnated Bed Nets during a Leishmaniasis Control Program in Iran.

BACKGROUND: The control of leishmaniasis, a tropical neglected disease, has been concern of Iranian health authorities due to the increasing number of cases during the last two decades. The objective of this study was to determine deltamethrine residue on the impregnated bed nets using HPTLC technique in a leishmaniasis control program in Iran. METHODS: During this experimental study, a total of 130 small pieces of polyester netting were sewn to top, upper, and lower sides of some bed nets and then were impregnated with deltamethrin. The treated bed nets were distributed in Isfahan and Mashhad areas in April 2003. The samples were cut randomly after impregnation intervals. Deltamethrin was extracted using acetone from samples and the extract was applied for spotting onto plates. The plates were developed with n-hexane: ethyl acetate, 90+10(v/v), as a mobile phase in a Camage chamber. The qualifying of residue was observed in UV cabinet with λ=254 nm wavelength. Data were analyzed using SPSS version 11.5. and Stata Version 8. A three way ANOVA was used to compare the means of deltamethrin residue in each area, group and measuring time. The Kruskal-Wallis test was used to compare the means of residue for each of these factors with the control separately. RESULTS: The retardation factor of deltamethrin was calculated 0.50±0.02. The residues of deltamethrin persisted well on impregnated nets at least for 15 weeks after impregnation. No significant difference could be detected in the loss of residue of insecticide in comparison to measuring times and positions of sampling pieces on the bed nets in these areas. CONCLUSION: Based on the results of the present study the use of HPTLC technique is recommended instead of other chromatographic methods for analysis of insecticide residue on the impregnated bed nets.

Anopheles culicifacies in Baluchistan, Iran.

Anopheles culicifacies (probably species A) is the main vector of malaria in Baluchistan, southeastern Iran. Adult mosquitoes were collected during 1990-92 by five methods of sampling: knock-down pyrethrum space-spray indoors, human and animal bait (18.00-05.00 hours), pit shelters and CDC light traps, yielding 62%, 3%, 6%, 4% and 25% of specimens, respectively. Whereas spray-catches comprised c. 70% gravid and semi-gravid females, light trap catches were mostly (c. 60%) unfed females, while females from pit shelters comprised all abdominal stages more equally (13-36%). An.culicifacies populations peaked in April-May and rose again during August-November. Densities of indoor-resting mosquitoes were consistently greater in an unsprayed village than in villages subjected to residual house-spraying with propoxur, malathion or pirimiphos-methyl. Monthly malaria incidence generally followed fluctuations of An.culicifacies density, usually with a peak in May-June.

Ecology of Anopheles pulcherrimus in Baluchistan, Iran.

Studies were conducted on the ecology of Anopheles pulcherrimus over a period of 20 months in the village of Zeineddini, Sistan and Baluchistan Province, southeastern Iran. The species was active throughout the year with 2 peaks of activity, April-May and August-September. Light traps captured the highest number of An. pulcherrimus females (65%) as compared to cattle bait collections (19.3%), pyrethrum space spray catches (14.2%), pit shelter (1%) and human bait collections (0.6%). However, 95% of the females captured in light traps were unfed or freshly fed females as opposed to about only 44% of those collected in pyrethrum space spray catches and pit shelter collections. The species was mainly exophilic as shown by the gravid/fed ratio of 0.4 obtained in outlet window traps.

Efficacy of a flowable concentrate formulation of Bacillus thuringiensis (H-14) against larval mosquitoes in southern Iran.

A flowable concentrate formulation of Bacillus thuringiensis (H-14) [Bactimos FC (1000 ITU/mg)] was evaluated for the control of mosquito larvae in simulated ponds and natural breeding sites in Kazeroun (Fars Province), southern Iran. A comparison was made with Abate emulsifiable concentrate. Bactimos FC caused 93-96% anopheline and 97% culicine larval mortality 24 h posttreatment in simulated ponds and natural breeding sites, when used at the rate of 0.2 cc/m2. Abate (0.015 cc/m2) resulted in significantly higher anopheline (98.1%) and culicine (100%) mortality at 24 h posttreatment. There was a relatively sharp decline in larval mortality 48 h posttreatment when Bactimos FC was applied. Five-day applications were suggested to prevent pupal production.

The prevalence of intestinal helminthiasis among the Qashqai tribe in Southern Iran.

The prevalence and the intensity of intestinal helminthiasis in the Qashqai tribe of Southern Iran were studied. Infection with Ascaris Lumbricoides and Trichuris Trichura was low (6.1 and 0.8 per cent respectively) while the prevalence of Trichostrongylus was 27.6 per cent of the total stool samples examined or 63.2 per cent of the total intestinal parasites found. This might be due to the mode of life of the tribe and the proximity of its people to domestic animals.

Prevalence of high blood pressure in Qashqai Tribe, Southern Iran, 1973.

On the basis cross sectional health and morbidity survey was conducted in 1973, an attempt was made to measure the prevalence of high blood pressure among Qashqai Tribe. Our study showed that hypertension is by no means a rare condition among nomads and it tends to be a little higher in women than in men age group 35 years and over. Our figures showed that the pattern of increase of prevalence of high blood pressure with the increase of age.

Ecology of Anopheles stephensi Liston in southern Iran.

Anopheles stephensi mysorensis is an important malaria vector in southern Iran. It is known to be the vector of malaria in Abadan, Bandar Abbas, Kazeroun and Dezful. It readily attacks man. Precipitan tests on specimens from different parts of southern Iran showed that 15.7% were positive for human blood. This species usually rests indoors, but a small proportion of its population has been caught outdoors. Larval habitats vary. This species is resistant to DDT and Dieldrin in most of the areas of the Persian Gulf and Oman sea.

Biological features of Anopheles fluviatilis and its role in the transmission of malaria in Iran.

Anopheles fluviatilis is a vector of malaria in the southern regions of Iran. Its biological features and its significance are described.

[Fertility and family planning among nomads].

PIP: In 1973 a random sample study was done in the south of Iran on 2930 married couples of the Qashigi tribe. It was to determine the fertility, knowledge, and practice of contraception, and attitudes toward birth control of this nomadic group. The fertility study involved 2167 women, aged 15-44. Early marriage is the norm, with 80% of them taking place before the age of 20 and the ideal age being 17. The average number of pregnancies per woman was 4.3; the ideal number of children was 6.1 (4.3 sons and 1.9 daughters). 92% felt the size of the family depended on the will of God. Also, families who had lost fewer children indicated a smaller number of children as an ideal. Of the 67% of married persons who had heard of family planning, 17% approved of it, but only about 2% practiced some form. The patrilineal system encourages high fertility. Social values and customs help relieve the pressure on parents for raising the children by thenselves.^ieng