Maria de Fátima de Souza

Density of Sand Flies (Diptera: Psychodidae) in Domestic and Wild Animal Shelters in an Area of Visceral Leishmaniasis in the State of Rio Grande do Norte, Brazil

The objective of the present study was to determine the association of sand flies with the presence of domestic and wild animals in the peridomiciliary area. The sand flies were collected using direct aspiration and CDC light traps placed in animal shelters. The results suggest that different sand flies species have different behavioral characteristics in an apparent preference for animal baits and that Lutzomyia longipalpis and Lu. evandroi were the most eclectic species regarding their biotope choice. Lu. longipalpis showed a distinct preference for horses and Lu. evandroi for armadillos.

Effect of abiotic factors on seasonal population dynamics of Lutzomyia longipalpis (Diptera: Psychodidae) in northeastern Brazil.

Abstract The resurgence of visceral leishmaniasis in Brazil increases the need for studies to elucidate the spatial and temporal dynamics of Lutzomyia longipalpis (Lutz & Neiva) (Diptera: Psychodidae), the vector of Leishmania infantum, the causative agent of visceral leishmaniasis in Brazil. Sand flies were captured in peridomestic habitats biweekly for 3 yr. Cross-correlation tests and spectral analysis were used to analyze the simultaneous and lag-time correlations between Lu. longipalpis population densities and abiotic factors of temperature, relative humidity, wind velocity, and rainfall. Distinct seasonal patterns were observed for males and females, with intervals of 6 mo between population peaks for males and 12 mo for females. Peak female population densities lagged 3 mo behind the maximum annual temperature. Female population density was negatively correlated with relative humidity. An increase in average wind velocity was followed by a decrease in the number of females for 2 wk. Understanding the relationship between the seasonal population dynamics of Lu. longipalpis and abiotic factors will contribute to the design of better control measures to decrease transmission of L. infantum and consequently the incidence of leishmaniasis.

Distribution of Phlebotomine Sand Flies (Diptera: Psychodidae) in the State of Rio Grande do Norte, Brazil

Abstract Visceral and cutaneous leishmaniasis are major endemic diseases in northeast Brazil. The objective of the current study was to determine the species and geographic distribution of potential sand fly vectors of Leishmania in the state of Rio Grande do Norte. Sand flies were captured using CDC light traps in 30 municipalities distributed throughout the 8 geographic zones of the state. Twelve Lutzomyia species were identified. Lutzomyia longipalpis Lutz & Neiva was the most prevalent and accounted for 85.59% of the sand fly captured. The remaining species were distributed as follows: L. evandroi Costa Lima & Antunes (10.83%), L. oswaldoi Mangabeira (0.99%), L. sallesi Galvão & Coutinho (0.58%), L. intermedia Lutz & Neiva (0.53%), L. lenti Mangabeira (0.53%), L. migonei França (0.49%), L. walkeri Newstead (0.24%), L. goiana Martins, Falcão & Silva (0.15%), L. samueli Deane (0.04%), and L. capixaba Dias, Falcão, Silva & Martins (0.03%), and L. peresi Mangabeira (0.01%). L. longipalpis, which is known to be a vector of Leishmania chagasi Cunha & Chagas (L. donovani chagasi), was captured in 93% of municipalities distributed across all geographical areas of the state and its distribution was independent of obvious climatic and topographic parameters. It was identified in all municipalities where human visceral leishmaniasis had been reported. In contrast, climate and topography appeared to be important for other Lutzomyia species. For example, L. intermedia and L. migonei, which are known to transmit Leishmania braziliensis Viana, were geographically restricted. They were captured in municipalities where cases of cutaneous and mucosal leishmaniasis had been reported. The widespread distribution of L. longipalpis, its adaptation to peridomicillary settings, and its ability to transmit L. (d.) chagasi suggest that a large number of persons may be at risk of acquiring visceral leishmaniasis in the state of Rio Grande do Norte, Brazil.

Gastrointestinal parasites of sheep, municipality of Lajes, Rio Grande do Norte, Brazil

This study investigated the gastrointestinal parasitism by helminths and protozoa in sheep (Ovis aries) Santa Inês breed, municipality of Lajes, Rio Grande do Norte. Monthly, from April 2005 to August 2007, stool samples were collected from two tracer lambs in the first day of the experiment and performed a necropsy of these animals in 44th day. A total of 64 lambs were sampled, but only 62 lambs were slaughtered. The fecal samples were examined by sedimentation in water. The contents of the abomasum, small intestine and large intestine were examined for the recovery of helminths. The parasitological examination revealed eggs of the following groups of helminths: Strongyloidea, Strongyloides sp., Trichuris sp., and Moniezia sp. Also were found oocysts of Eimeria spp., cysts of Entamoeba ovis and Giardia duodenalis. The helminths identified from examining the contents were: Haemonchus contortus, Cooperia pectinata, Cooperia punctata, Trichostrongylus colubriformis, Moniezia expansa, Oesophagostomum sp. Skrjabinema ovis and Trichuris sp.

Natural infection by Eimeria spp. in a cohort of lambs raised extensively in Northeast Brazil

The aim of the study was to examine and describe the changes in the course of Eimeria infection in a cohort of lambs of the mixed breed Santa Inês raised extensively on a farm in the State of Rio Grande do Norte, northeastern Brazil. The study was carried out between April and August 2008, during which period fecal samples were collected on a weekly basis from each of the 27 male lambs starting from the day after birth until the age of 90 days. Samples were analyzed under optical microscope a nd those testing positive for Eimeria oocysts were submitted to a quantitative analysis. Oocysts were detected in 17% of the lambs by week 3, but by week 6 100% of the animals were infected. Eight species of Eimeria were identified in the fecal samples, namely, in decreasing order of prevalence, E. crandallis, E. parva, E. granulosa, E. ovinoidalis, E. ahsata, E. ovina, E. faurei and E. intricata. Of the 191 fecal samples that contained Eimeria oocysts, only 32 (16.8%) were infected with a single species whereas 23 (12.0%) were infected with at least two species and 136 (71.2%) harbored three or more species. Although Eimeria coccidiosis is a complex disease owing to the mixed nature of the infective agents, an ongoing prevention program should be implemented to reduce production losses.