The abundance and activity of ectoparasites and its hosts are affected by various abiotic factors, such as climate and other organisms (predators, pathogens and competitors) presenting thus multiples forms of association (obligate to facultative, permanent to intermittent and superficial to subcutaneous) developed during long co-evolving processes. Ticks are ectoparasites widespread globally and its eco epidemiology are closely related to the environmental conditions. They are obligatory hematophagous ectoparasites and responsible as vectors or reservoirs at the transmission of pathogenic fungi, protozoa, viruses, rickettsia and others bacteria during their feeding process on the hosts. Ticks constitute the second vector group that transmit the major number of pathogens to humans and play a role primary for animals in the process of diseases transmission. Many studies on bioecology of ticks, considering the information related to their population dynamics, to the host and the environment, comes possible the application and efficiency of tick control measures in the prevention programs of vector-borne diseases. In this review were considered some taxonomic, morphological, epidemiological and clinical fundamental aspects related to the tick-borne infections that affect human and animal populations.
Brazilian spotted fever (BSF), caused by Rickettsia rickettsii, is endemic in the municipality of Americana, southeastern Brazil, where the disease is transmitted by the tick Amblyomma cajennense. This study evaluated the tick fauna and rickettsial infection in free-living ticks that were captured monthly using dry ice traps in areas endemic for BSF in Americana, from July 2009 to June 2010. Two tick species were captured: A. cajennense (6,122 larvae; 4,265 nymphs; 2,355 adults) and Amblyomma dubitatum (7,814 larvae; 3,364 nymphs; 1,193 adults). The immature stages of A. cajennense and A. dubitatum had similar distribution through the 12-month period, with larvae of both species collected in highest numbers between April and July, and nymphs between June and October. The highest numbers of A. cajennense adults were collected between October and December, whereas A. dubitatum adults were collected in relatively similar numbers throughout the 12-month period. Rickettsial infection was evaluated by means of PCR in 1,157 A. cajennense and 1,040 A. dubitatum ticks; only 41 (3.9%) A. dubitatum were found to be infected by Rickettsia bellii. The present study showed that the areas of Americana that are endemic for BSF are characterized by high environmental burdens of A. cajennense and A. dubitatum.
Aim:In this work, we aimed to develop maps of modeling geographic distribution correlating to environmental suitability for the two species of scorpions of medical importance at São Paulo State and to develop spatial configuration parameters for epidemiological surveillance of these species of venomous animals.Materials and Methods:In this study, 54 georeferenced points for Tityus serrulatus and 86 points for Tityus bahiensis and eight environmental indicators, were used to generate species distribution models in Maxent (maximum entropy modeling of species geographic distributions) version 3.3.3k using 70% of data for training (n=38 to T. serrulatus and n=60 to T. bahiensis) and 30% to test the models (n=16 for T. serrulatus and n=26 for T. bahiensis). The logistic threshold used to cut models in converting the continuous probability model into a binary model was the “maximum test sensitivity plus specificity,” provided by Maxent, with results of 0.4143 to T. serrulatus and of 0.3401 to T. bahiensis. The models were evaluated by the area under the curve (AUC), using the omission error and the binomial probability. With the data generated by Maxent, distribution maps were produced using the “ESRI® ArcGIS 10.2.2 for Desktop” software.Results:The models had high predictive success (AUC=0.7698±0.0533, omission error=0.2467 and p<0.001 for T. serrulatus and AUC=0.8205±0.0390, omission error=0.1917 and p<0.001 for T. bahiensis) and the resultant maps showed a high environmental suitability in the north, central, and southeast of the state, confirming the increasing spread of these species. The environmental variables that mostly contributed to the scorpions species distribution model were rain precipitation (28.9%) and tree cover (28.2%) for the T. serrulatus and temperature (45.8%) and thermal amplitude (12.6%) for the T. bahiensis.Conclusion:The distribution model of these species of medical importance scorpions in São Paulo State revealed a higher environmental suitability of these species in the regions north, central, and southeast of the state, warning to emergencies actions for prevention and surveillance from scorpion stings in several counties. There is also a need to best conservation strategies related to neighboring territories, with the implementation of new environmental protected areas and measures of spread control of these species in urban areas of several counties.
In the last years, the fruit fly Zapronius indianus became the most important plague of Brazilian fig production. A fermentation process is associated with infection of the fruit by this fly. A single yeast species, Candida tropicalis, was identified in all the infected figs. The presence of one species and the low genetic variability (RAPD) of the isolates indicates an uncommonly strict interaction between C. tropicalis and Z. indianus.
Key words: Zaprionus indianus, Candida tropicalis, RAPD markers, yeast-insect associationThe first register of the occurrence of Zaprionus indianus in the American continent was made in Japanese pergammon fruits in São Paulo State, Brazil. In the same region and agricultural season, these flies were observed feeding and laying eggs at the ostiole region of fig fruits in the beginning of the maturation period (14). This fly of African origin, recently introduced in Brazil, is not considered a plague in Africa. However, the loss estimates in fig production in Brazil since its appearance is around 50%, becoming the most important plague of this fruit in less than two years from the first report.The genus Zaprionus is formed by two sub-genera and 56 species (3). Z. indianus is the only species observed in tropical regions like the Comores Islands, Madagascar, Reunion Islands, Canary Islands, India, Sauddith Arabia (2), and now in Brazil. Z. indianus is a fly of about 2.5 to 3.0 mm length, with light brown body, red eyes, and characteristic longitudinal black and white stripes along the dorsal region of the head and thorax.Most of the species of the Drosophilidae family are associated to yeast and bacteria communities. Metschnikowia hawaiiensis (6), Candida amapae, Kloeckera sp., Hanseniaspora sp., Candida guillermondii, and C. krusei The study of the microbial communities associated to the drosophilid Zaprionus indianus is especially important considering the plague status of this fruit fly in Brazil. In the present paper, we identified the yeast species associated with Zaprionus indianus in the subtropical region of São Paulo State, Brazil.Four infested and four non infested figs were collected at four different farms at the Valinhos region, São Paulo State, Brazil, giving a total of sixteen infested and sixteen non infested fruits. The figs were opened and samples from the inner part of the fruits were plated on appropriate media.Yeasts were isolated on YEPD (1% yeast extract, 1% peptone, 2% glucose, and 2% agar) medium with 100 mg/l of ampicilin, 25 mg/l of tetracycline and 100 mg/l of kanamycin. Bacteria were isolated on YEPD medium with 100 mg/l of nystatin. Ten yeast and bacterial colonies from each sample were isolated and purified on the above media.
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