RESUMEN
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.
Asunto(s)
Anopheles , Animales , Femenino , Humanos , Insecticidas , Irán/epidemiología , Malaria/epidemiología , Malatión , Masculino , Compuestos Organotiofosforados , Densidad de Población , Propoxur , Estaciones del AñoRESUMEN
Survival rates, expectation of life, and expectation of infective life of Anopheles culicifacies and Anopheles pulcherrimus were estimated in sprayed and unsprayed villages in the highly malarious Ghassreghand District, Iran, during the 2 peak malaria transmission seasons in 1991. The daily survival rate of An. culicifacies was estimated as 0.84 and 0.78 during May and 0.89 and nil during September-October in the unsprayed and sprayed villages, respectively. For An. pulcherrimus the daily survival rate was estimated as 0.80 and 0.78 in May and 0.83 and 0.78 in September-October in the unsprayed and sprayed villages, respectively. The impact of indoor residual spraying during the first peak of transmission on An. culicifacies and An. pulcherrimus (expressed as the product of the degree of reduction of the expectation of infective life and the degree of reduction of expectation of life) was calculated as 3.5 and 1.5 times, respectively, that in the absence of control. The impact of indoor residual spraying on An. culicifacies during the second peak of transmission was almost complete, whereas that for An. pulcherrimus was 3.4 times than that in the absence of control.
Asunto(s)
Anopheles , Control de Mosquitos , Animales , Irán , Dinámica Poblacional , Factores de TiempoRESUMEN
A 2-site immunoradiometric assay (IRMA) was performed on the head and thorax of Anopheles culicifacies s.l. and An. pulcherrimus females, the 2 most common anopheline species in the District of Ghassreghand (Baluchistan, Iran), collected during the 2 peak malaria transmission seasons (May and September-October 1991). Positive IRMA results revealed the 2 species as potential vectors of malaria in this highly endemic district. This finding serves as the first report on natural infection of An. pulcherrimus in Iran and is the second on natural infection of An. culicifacies since the previous report of 1959.
Asunto(s)
Anopheles/parasitología , Insectos Vectores , Malaria/transmisión , Animales , Demografía , Ecología , Femenino , Humanos , Ensayo Inmunorradiométrico , Incidencia , Irán/epidemiología , Malaria/epidemiología , Plasmodium falciparum/aislamiento & purificación , Densidad de Población , Estaciones del AñoRESUMEN
Since 1958, when the malaria eradication program officially started in Iran, great strides has been made in controlling the disease in most of the country. However, because of certain technical, operational and administrative problems, malaria is still highly prevalent in southeastern Iran, affecting 6% of the population. The situation of malaria in Iran from 1975 through 1990 is discussed in detail, with particular emphasis given to the epidemiological characteristics and vector transmission factors in each region of the country.
Asunto(s)
Malaria/epidemiología , Malaria/prevención & control , Animales , Anopheles , Humanos , Insectos Vectores , Irán/epidemiología , Malaria/transmisión , Control de Mosquitos/métodos , Plasmodium , PrevalenciaRESUMEN
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.
Asunto(s)
Anopheles , Ecología , Animales , Entomología/métodos , Femenino , Irán , Vigilancia de la Población , Estaciones del Año , Especificidad de la EspecieRESUMEN
The efficacy of the parasitic nematode Romanomermis culcivorax in controlling anopheline larvae, including malaria vectors, was studied in Fars and Baluchistan provinces. Twenty sites were treated once with the preparastic stage of R. culicivorax in 1984 with 3,000, 5,000 or 10,000 preparasites per m2 surface area, depending on larval density. The average parasitism of anopheline larvae ranged from 56 to 69% based on 24 hr posttreatment dissections. No correlation was found between the level of parasitism and the density of mosquito larvae present in a site. About 61% parasitism was obtained when different rates of preparasites were released in 14 larval breeding sites in 1985. No apparent difference was observed in the rate of parasitism in 10 sites receiving one treatment compared with four sites receiving two treatments, with a seven day interval between each treatment. Romanomermis culcivorax was established in the release sites but caused only minor reductions in anopheline larval populations. The nematode would be of limited use in antimalaria campaigns in southern Iran.
Asunto(s)
Anopheles/parasitología , Malaria/prevención & control , Mermithoidea/fisiología , Control de Mosquitos/métodos , Animales , Interacciones Huésped-Parásitos , Humanos , Irán , Larva/parasitologíaRESUMEN
In southern Iran, adults of Anopheles stephensi, the main vector of malaria, are resistant to DDT, dieldrin and malathion. Susceptibility tests carried out with propoxur-impregnated papers during 1976-86 in 5 villages in Minab County, showed that, despite 10 years of propoxur application twice a year in dwellings, An. stephensi remained susceptible to this insecticide.
Asunto(s)
Anopheles , Propoxur , Animales , Resistencia a Medicamentos , Irán , Control de MosquitosRESUMEN
An investigation was carried out over a year in the village of Chelow, Hormozgan Province, southern Iran, to study the efficacy of CDC light traps for sampling malaria vectors. The CDC light traps were useful in determining the seasonal and habitat distribution of Anopheles stephensi and An. fluviatilis, the primary and secondary vectors of malaria, in Chelow, as well as other mosquitoes in that area. Light traps compared favorably with other adult mosquito collection techniques for detecting the presence of vectors during periods of low density. In Iran, time and labor-saving features and flexibility for use in different situations make CDC light traps a useful sampling tool in the entomological assessment of malaria control programs.
Asunto(s)
Anopheles , Entomología/instrumentación , Insectos Vectores , Malaria/transmisión , Animales , Humanos , IránRESUMEN
Study to monitor the susceptibility of P. falciparum to chloroquine in south Iran was conducted in Bandar Abbas. Forty-five falciparum malaria subjects who had received 25mg. chloroquine base per kg. body weight over 3 days were followed up for 4 weeks, while three other patients for a period of 1-3 weeks. No recrudescence could be confirmed among the subjects during the follow up of the study. The mean time of asexual parasites clearance was 2.15 days. The action of chloroquine against the asexual form of P. falciparum in the present study was suspected to be slower as compared with those observed in the previous studies. However, both in vivo and limited study using the in vitro technique showed that the response of P. falciparum asexual parasites to chloroquine was still satisfactory. The study supports previous findings in Ethiopia that acquired immunity malaria had no significant effect on the asexual parasite clearance time.
Asunto(s)
Cloroquina/farmacología , Plasmodium falciparum/efectos de los fármacos , Adolescente , Adulto , Células Sanguíneas/parasitología , Niño , Preescolar , Cloroquina/administración & dosificación , Cloroquina/uso terapéutico , Resistencia a Medicamentos , Geografía , Humanos , Irán , Recuento de Leucocitos , Malaria/sangre , Malaria/tratamiento farmacológico , MasculinoRESUMEN
In southern Iran during the hot season inhabitants sleep outddoors. Therefore the biting cycles of three outdoor resting mosquitoes, Anopheles dthali, fluviatilis and stephensi have been studied. Most of the bites take place between 18-24 h.
Asunto(s)
Anopheles/fisiología , Animales , Conducta Alimentaria , Humanos , Irán , Estaciones del AñoRESUMEN
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.