Effect of diflubenzuron on immature stages of Haematobia irritans (L.) (Diptera: Muscidae) in Uberlândia,State of Minas Gerais,Brazil

Horn fly immatures were raised in media containing different concentrations of diflubenzuron in order to verify their susceptibility to this insect growth regulator (IGR). The 50% and 95% lethal concentrations of diflubenzuron for the population (LC50, LC95) were determined as well as the effect of this IGR on the different immature horn fly stages. The tests were performed using the progeny of adults collected in the field. The immatures were maintained in a growth chamber at 25.0 +/- 0.5oC and 12-12 h photoperiod. IGR concentrations of 300 ppb, 100 ppb and 50 ppb were lethal for 100% of the sample. Pupae malformation occurred in the breeding media containing different diflubenzuron concentrations. Values for LC50, LC95 (+/- 95% fiducial limits) and the slope of the regression line were respectively, 25.521 +/- 1.981 ppb, 34.650 +/- 2.001 ppb and 12.720 +/- 1.096. The third larval instar was more sensitive to the sub-lethal concentration of the product than the first and second ones were. The results indicate that this IGR can be an important tool for controlling horn fly populations as well as for managing horn fly resistance to conventional insecticides against Haematobia irritans in Uberlandia, State of Minas Gerais.     

Survey of ants (Hymenoptera: Formicidae) in the urban area of Uberlândia, MG, Brazil

Uberlandia, MG, Brazil, underwent an accelerated process of urbanization with a population growth of 3,54% each year, higher than the national average. One of the problems emergent from urbanization is the use of different habitats for a great variety of insects. The objective of this study was to identify species of house-invading ants that occur in the urban area of Uberlandia. The occurrence of the house-invading species in regard to the time of urbanization, neighborhood infrastructure, age and maintenance of private houses was also assessed. The ants were collected using bait-traps in 120 residences from 12 neighborhoods which were put in three groups. Fourteen species of ants were catalogued, with Camponotus (Mayr), Monomorium (Mayr) and Tapinoma (Foerster) being the most frequent genera. Only Camponotus vittatus (Forel), Monomorium pharaonis (L.), Tapinoma melanocephalum (Fabricius) and Brachymyrmex sp. (Mayr) were collected in all three groups. The relation between the ants collected and the age and maintenance of the private houses showed that Paratrechina longicornis (Latreille) was most frequent (60%) in poorly preserved or precarious constructions. Whereas, C. vittatus and Camonotus melanoticus (Emery) occurred in all categories of maintenance. Overall, C. vittatus which had not been found in any previously published survey of urban ants, was the most frequent species in urban areas of the Cerrado.     

Capybaras and ticks in the urban areas of Uberlândia,Minas Gerais,Brazil: ecological aspects for the epidemiology of tick-borne diseases

In Brazil capybara, the biggest existing rodent species, and associated tick species, Amblyomma cajennense and Amblyomma dubitatum, are undergoing an unplanned host and parasite population expansion in both urban and rural areas. However, scientific information about such issue, particularly in urban areas, is scanty. Such rodent and ticks are associated in some municipalities, particularly in southeastern Brazil, with the transmission of the highly lethal Rickettsia rickettsia caused spotted-fever. In this study ecological aspects related to the establishment and expansion of capybaras and ticks in urban areas of Uberlandia, Minas Gerais State, Brazil were evaluated. For this purpose, capybara and tick abundance in four urban areas and an ecological reserve was determined. Abundance of capybaras varied between areas and over the sampling period and these differences were related to human activities. A positive correlation was found between capybara and tick abundance, however, the tick species had an uneven distribution within the municipality and environmental factors rather than host availability were blamed for such. On the whole these observations show that capybara populations in urban areas are associated to high environmental infestation of ticks and the increased risk of bites and of pathogen transmission to humans. At the same time the uneven distribution of tick species might implicate in an unequal risk of tick-borne diseases within the same urban area.     

Species Diversity and Temporal Variation of the Orchid-Bee Fauna (Hymenoptera, Apidae) in a Conservation Gradient of a Rocky Field Area in the Espinhaço Range, State of Minas Gerais, Southeastern Brazil

This study investigated the orchid-bee community in a conservation gradient of the high-altitude rocky fields in the state of Minas Gerais, Brazil. Sampling was performed at two sites with different anthropic influences: a disturbed area (DA), with exotic plant species, and a preserved area (PA). From September 2009 through February 2011, males of euglossine bees were sampled using aromatic bait-traps. We collected a total of 819 specimens belonging to 11 species and three genera: Euglossa Latreille, Eulaema Lepeletier, and Eufriesea Cockerell. Despite the proximity of DA and PA (about 1.2 km), differences in orchid-bee abundance and richness were observed. Higher abundance was observed in the PA (n?=?485) compared with the DA (n?=?334). Eight species were common to both sites, and only the DA showed exclusive species. The DA showed higher diversity and higher estimated species richness. Euglossa leucotricha Rebêlo & Moure was the most abundant species at both sites followed by Euglossa melanotricha Moure. Higher abundance and richness were found in the warm rainy season. This study contributes to the knowledge of the orchid-bee fauna in the rocky fields and suggests that the greater resource availability in the DA was responsible for the higher orchid-bee diversity.     

Four new records of the phlebotominic fauna of the Genus Lutzomyia França (Diptera: Psychodidae, Phlebotominae) of the rural district of Brejo do Mutambal, Varzelândia, State of Minas Gerais, Brazil

During April and May 2006, experiments were carried out in Brejo do Mutambal, Varzelandia Town, Minas Gerais State, to evaluate the attractiveness of phlebotomine sandflies to CDC light traps, baited with kairomones. Of the 19 species of Lutzomyia already registered for the region, L. lutziana (Costa Lima), L. longipennis (Barreto), L. goiana (Martins, Falc?o & Silva) and L. brasiliensis (Costa Lima) were recorded for the first time, thus increasing the diversity of phlebotomine sandflies fauna in this area to 23 species. The new registered species and distribution are shown and discussed herein.     

Population dynamics of Triatoma vitticeps (Stål, 1859) in Itanhomi, Minas Gerais, Brazil

Taxonomic markers (head structure morphometry, isoenzymes and randon amplified polymorphism of DNA - RAPD) were used to understand the population dynamics of Triatoma vitticeps, predominant triatomine species in Itanhomi district, using samples obtained from domestic, peridomiciliary and sylvatic habitats. Morphometric analysis revealed sexual dimorphism within the three samples although specimens could not be separated according to the habitat in which they were captured. Forty-two bands were analyzed from RAPD profiles generated using four primers. A dendrogram constructed from Dice's similarity coefficient values showed that migration of the insects between the habitats has occurred, without structuring of populations. Moreover, the dendrogram obtained from the genetic distance values showed an important gene flow between the sylvatic and domestic habitats. No polymorphism was found in the electrophoretic mobility of proteins for the ten enzymes studied. Our results revealed movement of triatomines between the three habitats, suggesting that the presence of T. vitticeps in houses should not be ignored. As invasion of houses by sylvatic insects is frequent and the natural infection indices of this species are among the highest known, epidemiological vigilance studies may reveal possible changes in T. vitticeps behaviour which could present future risks to public health.     

Lepidoptera pests collected in Eucalyptus urophylla (Myrtaceae) plantations during five years in Três Marias,State of Minas Gerais,Brazil

Lepidoptera pest species from eucalyptus were collected in Eucalyptus urophylla plantations in the region of Três Marias, State of Minas Gerais, Brazil, every 15 days from June 1989 to June 1994 with five light traps. Twelve primary and 15 secondary pest species were collected in the period with an average of 13,387 and 812 individuals per light trap, respectively. Most collected primary pest species were Stenalcidia grosica (Geometridae), Iridopsis subferaria (Geometridae), Eupseudosoma aberrans (Arctiidae) and Psorocampa denticulata (Notodontidae), totalizing for the study period an average of 5,450, 2,162, 2,436 and 1,458 individuals per light trap, respectively. Idalus admirabilis (Arctiidae) was the most collected secondary pest species, averaging 652 individuals/trap. Most primary pest species were collected during the dry season, from April to July, whereas most secondary pest species were collected during the rainy season, from January to March. These differences on seasonal occurrence between the two groups could be due to the fact that many secondary pest species of Eucalyptus in Brazil pupate in the soil, and they need humidity to complete its pupal stage.     

Natural enemies of Coelomera lanio (Coleoptera: Chrysomelidae) in the region of Viçosa,Minas Gerais,Brazil

Coelomera lanio (Coleoptera: Chrysomelidae) is the most important defoliator of Cecropia trees. Natural enemies of C. lanio collected in the region of Vi?osa, State of Minas Gerais, Brazil were identified on field observations in a forest fragment and on laboratory analyses. Individuals of C. lanio were not found on Cecropia pachystachya trees colonized by Azteca mülleri (Hymenoptera: Formicidae). The majority of the egg masses of C. lanio collected in the field were found to be parasitised by a species of the family Eulophidae (Hymenoptera), while larvae of this pest were attacked by a parasitoid of the family Tachinidae (Diptera). Individuals of Oplomus catena (Heteroptera: Pentatomidae) were observed preying on C. lanio larvae. The fungus Beauveria bassiana was found growing on larvae, pupae and adults of C. lanio while the fungus Metarhizium anisopliae only affected pupae of this insect in laboratory conditions.     

Epidemiological aspects of head lice in children attending day care centres,urban and rural schools in Uberlândia,central Brazil

From November 1996 to March 2000, a total of 884 children between 0 and 15 years, from 11 institutions including day care centres, public urban and public rural schools in Uberlandia, State of Minas Gerais, central Brazil, were examined for head louse infestation. Children's sex, race, age and some hairs characteristics were shown to be associated to parasite infestation. A prevalence rate of 35% was found and the highest rates were observed in black, female children, with long, dark, wavy hairs. Hairs density and thickness did not seem to influence significantly the distribution of this pediculosis in Uberlandia's schoolchildren. Differences observed between the prevalence rates of head lice in children from the urban institutions suggest there is a greater epidemiological heterogeneity in this group when compared to the rural schoolchildren.     

Seroprevalence of Toxoplasma gondii infection in goats by the indirect haemagglutination, immunofluorescence and immunoenzymatic tests in the region of Uberlândia, Brazil

A comparative study of the indirect haemagglutination (IHA), immunofluorescence (IFAT) and immunoenzymatic (ELISA) tests was carried out to determine the prevalence of Toxoplasma gondii antibodies in goats. One hundred seventy-four serum samples were obtained from four goat herds from the region of Uberlandia, State of Minas Gerais. The distribution of the animals, according to their origin, was as follow: 71 from herd I; 39 from herd II; 37 from herd III; and 27 from herd IV. Serum samples were analyzed by IHA, IFAT and ELISA, considering the reactivity of the serum samples at dilution > or = 1:64 as cut off titer for the three tests. A global seroprevalence of 18.4% was observed, with significantly higher positivity rate in the herd II (66.7%) and older animals (> 36 months). A high and significant positive correlation was found between the titers obtained by the IHA versus IFAT, IHA versus ELISA, and ELISA versus IFAT. Therefore, it can be concluded that the three analyzed tests have shown to be highly concordant and appropriate for epidemiological surveys of Toxoplasma infection in goats. Although the seroprevalence of T. gondii infection in goats is relatively low in this region as compared to other regions of the country, adequate management might be useful and essential to control the infection in the goat herds.     

Phlebotomine fauna (Diptera,Psychodidae) in Rio Preto State Park,Southern Espinhaço Range,Minas Gerais,Brazil

A study of the phlebotomine sand fly fauna was carried out in the Rio Preto State Park (Minas Gerais, Brazil) aiming to associate the presence of vector species with the risk of leishmaniasis transmission in that region. Sand flies were captured using HP light traps for four months from January to October 2013. The traps were exposed continuously for 40 h each month, in nine fixed sites. A total of 3129 sand flies were captured, belonging to 19 species. Lutzomyia evandroi (Costa Lima & Antunes 1936) was the predominant species (76.48%). The distribution of the phlebotomine sand flies and climatic factors (temperature, humidity, and rainfall) was evaluated. The summer was the season with higher occurrence of insects captured (82.4%). The presence of cutaneous and visceral vector species in park areas requires attention and regular monitoring of sand fly fauna in this conservation area to ensure the well-being of visitors and the regional ecotourism.     

A comparative study of congenital toxoplasmosis between public and private hospitals from Uberlândia, MG, Brazil

The main purpose of the present study was to examine if there is difference in terms of incidence rates of congenital toxoplasmosis among populations assisted in public and private hospitals from Uberlandia, state of Minas Gerais, Brazil. A total of 805 serum samples from cord blood were collected, being 500 from public hospital and 305 from private hospital, and all patients answered a questionnaire about pregnancy and newborns. An indirect enzyme linked immunosorbent assay (ELISA) was performed to detect IgG antibodies to Toxoplasma gondii and the positive samples were retested to verify the presence of specific IgM and IgA antibodies in a capture ELISA. We found significant differences among data from both hospitals with respect to maternal age, origin city, gestational age, number of visits to physicians during pregnancy, type of delivery, and birth weight. Seroprevalence of IgG antibodies against T. gondii for patients from public and private hospitals was 57.6% and 41.9% respectively, and this difference was statistically significant (P < 0.0001). In addition, the frequency of congenital toxoplasmosis measured by the presence of IgM and/or IgA antibodies toward T. gondii was exclusively located in samples from public hospital (0.8%), and no positive sample was seen in private hospital (0%). Considering that almost all babies suffering from congenital toxoplasmosis, if undiagnosed and untreated, will develop visual or neurological impairments by adulthood, the results presented herein emphasized the importance to accomplish screening programs for toxoplasmosis during pregnancy, particularly in the public hospitals, due to the expressive rate of congenital disease showed in the patients attended at these centers.     

Diversity of bees and their floral resources at altitudinal areas in the Southern Espinhaço Range, Minas Gerais, Brazil

The Southern Espinha?o Range consists of large areas covered by quartzitic or metaliferous tropical altitudinal fields. The Espinha?o Range ecosystems are endangered by anthropic high impacts, particularly due to mining and urbanization. We conducted a one-year inventory of the bee flora and fauna at the quartzitic Ouro Branco Mountains and a two-year survey of the metaliferous Ouro Preto fields. The samples were collected twice a month, from 8:00 am to 5:00 pm. The bees (677) belonged to 91 species, five families. The family Apidae was the richest and most abundant, followed by the Halictidae and Megachilidae. The bees visited 46 flowering plant species; the most visited plants were the Asteraceae (n = 220), the Malpighiaceae (n = 95), the Melastomataceae (n = 94), the Fabaceae (n = 78), and the Solanaceae (n = 63). Diversity was higher in Ouro Branco (H = 1.47) than in Ouro Preto (H = 1.17). The low richness and abundance of bees in our research site when compared to other Brazilian "Cerrado" areas can be due to the high altitude, low temperature, and low availability of flowers we found. "Canga" and rupestrian areas house fauna and flora species that are rare and threatened by extinction. The southern Espinha?o areas can, therefore, be given the status of permanent biodiversity preservation area.     

The threat of reintroduction of natural transmission of Chagas' disease in Bambuí, Minas Gerais State, Brazil, due to Panstrongylus megistus.

In the Epidemiological Surveillance Program in the county of Bambuí, Minas Gerais, between August 1986 and December 1988, 154 Panstrongylus megistus were captured by the local population in both peridomicile and intradomicile environments. Fifteen (9.8%) of the P. megistus harboured Trypanosoma cruzi. Precipitin tests showed that the most frequent triatomine blood meal sources were birds, but other sources were dogs, men and cats. The isoenzyme characterization of 13 T. cruzi strains showed that six belonged to zymodeme Z1, corresponding to the wild cycle parasites, and seven belonged to zymodeme Z2, corresponding to parasites isolated from chronic chagasic patients (domestic cycle). As P. megistus were found to be naturally infected by parasites from both cycles. They are clearly able to transmit T. cruzi from the wild cycle to the domestic cycle. Furthermore the capacity of P. megistus in colonizing houses was observed in one residence, vacant for several years, in which 153 triatomines were captured. The data show the possibility of P. megistus reintroducing the natural transmission of Chagas' disease in the county if Epidemiological Surveillance is interrupted.     

First report of Panstrongylus megistus sylvatic focus in municipality of Bambuí, state of Minas Gerais, Brazil

In 1943, the Center for the Study and Prophylaxis of Chagas Disease, Oswaldo Cruz Foundation, state of Minas Gerais (MG), was created in the municipality of Bambuí to carry out studies related to Chagas disease in the mid-western region of MG. Since that time, several investigations have been conducted to determine the natural habitat of triatomines, but Panstrongylus megistus colonies have never been found in this region. This paper records the first finding of a P. megistus sylvatic colony in 69 years of research. The characteristics of this ecotope and its implications for the epidemiology of Chagas disease are discussed.     

Nesting biology of Asian paper wasps Polistes chinensis antennalis Pérez,and Australian paper wasps P. humilis (Fab.) (Hymenoptera: Vespidae) in northern New Zealand

Abstract

We recorded the numbers of cells, and where possible distinguished between cells containing pupating larvae and vacated cells, from 585 paper wasp nests from the northern North Island, New Zealand, plus nest site characteristics of 540 of these nests. Nests of Polistes chinensis antennalis and P. humilis developed at similar rates in early summer. P. c. antennalis nests were larger at the Post‐emergence stage than those of P. humilis, and contained more vacated cells but less capped cells. All of the P. c. antennalis nests had reached the Post‐emergence stage by February in Northland, but not in the other regions. P. c. antennalis nests in the Post‐emergence stage were larger in Northland than further south, and contained the most capped or vacated cells. Nests of both species were usually found in northern‐facing sites. Substrate did not affect nest size. Differences between the species in nest sites included greater use of manmade structures by P. c. antennalis; the use of leaves by P. humilis only; and a higher average nest site height in P. humilis. These differences in nest site selection may reduce competition between the species.     

Pre-Columbian Chagas disease in Brazil: Trypanosoma cruzi I in the archaeological remains of a human in Peruaçu Valley, Minas Gerais, Brazil

We evaluated the presence and distribution of Trypanosoma cruzi DNA in a mummy presenting with megacolon that was dated as approximately 560 +/- 40 years old. The mummy was from the Perua?u Valley in the state of Minas Gerais, Brazil. All samples were positive for T. cruzi minicircle DNA, demonstrating the presence and broad dissemination of the parasite in this body. From one sample, a mini-exon gene fragment was recovered and characterized by sequencing and was found to belong to the T. cruzi I genotype. This finding suggests that T. cruzi I infected humans during the pre-Columbian times and that, in addition to T. cruzi infection, Chagas disease in Brazil most likely preceded European colonization.     

A new species of Sauvagesia (Ochnaceae) from the Espinhaço range of Minas Gerais, Brazil

The new species Sauvagesia lagevianae is described, illustrated, and discussed. This species is morphologically similar to S. glandulosa, but can be easily distinguished by its unique umbellate inflorescence arising from a distinct peduncle on the branch apex. Other diagnostic characters to identify S. lagevianae are the nodding, campanulate corollas, bi-apiculate anthers, and the small and strongly imbricate leaves with fewer and ascending secondary veins. The new species is only known from two nearby localities of “campo rupestre” vegetation in the Espinhaço range of Minas Gerais, Brazil.     

Invasion by the Introduced Aquatic Snail Melanoides tuberculata (Müller, 1774) (Gastropoda: Prosobranchia: Thiaridae) of the Rio Doce State Park,Minas Gerais,Brazil

During quantitative samples of invertebrate fauna in two lakes in the Rio Doce State Park (Marliéria, MG) I found some individuals of the introduced aquatic snail Melanoides tuberculata. It was most abundant in areas with high human activity, where the original vegetation was removed from the shallow areas near the margin. Population structure inferred by size-class data suggests that the most impacted area was invaded first and that these snails maintain a viable population in Dom Helvécio lake. Potential spread of the snail in this lake system is tentatively related to the characteristics of the bank vegetation and I presume that the not yet invaded Carioca lake has better conditions for an exponential growth of this species.     

Respiratory viruses in children younger than five years old with acute respiratory disease from 2001 to 2004 in Uberlândia, MG, Brazil

The main viruses involved in acute respiratory diseases among children are: respiratory syncytial virus (RSV), influenzavirus (FLU), parainfluenzavirus (PIV), adenovirus (AdV), human rhinovirus (HRV), and the human metapneumovirus (hMPV). The purpose of the present study was to identify respiratory viruses that affected children younger than five years old in Uberlandia, Midwestern Brazil. Nasopharyngeal aspirates from 379 children attended at Hospital de Clínicas (HC/UFU), from 2001 to 2004, with acute respiratory disease, were collected and tested by immunofluorescence assay (IFA) to detect RSV, FLU A and B, PIV 1, 2, and 3 and AdV, and RT-PCR to detect HRV. RSV was detected in 26.4% (100/379) of samples, FLU A and B in 9.5% (36/379), PIV 1, 2 and 3 in 6.3% (24/379) and AdV in 3.7% (14/379). HRV were detected in 29.6% (112/379) of the negative and indeterminate samples tested by IFI. RSV, particularly among children less than six months of life, and HRV cases showed highest incidence. Negative samples by both IFA and RT-PCR might reflect the presence of other pathogens, such as hMPV, coronavirus, and bacteria. Laboratorial diagnosis constituted an essential instrument to determine the incidence of the most common viruses in respiratory infections among children in this region.