21 research outputs found

    Onchocerciasis transmission in Ghana: biting and parous rates of host-seeking sibling species of the Simulium damnosum complex

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    Background: Ghana is renowned for its sibling species diversity of the Simulium damnosum complex, vectors of Onchocerca volvulus. Detailed entomological knowledge becomes a priority as onchocerciasis control policy has shifted from morbidity reduction to elimination of infection. To date, understanding of transmission dynamics of O. volvulus has been mainly based on S. damnosum sensu stricto (s.s.) data. We aim to elucidate bionomic features of vector species of importance for onchocerciasis elimination efforts. Methods: We collected S. damnosum sensu lato from seven villages in four Ghanaian regions between 2009 and 2011, using standard vector collection, and human- and cattle-baited tents. Taxa were identified using morphological and molecular techniques. Monthly biting rates (MBR), parous rates and monthly parous biting rates (MPBR) are reported by locality, season, trapping method and hour of collection for each species. Results: S. damnosum s.s./S. sirbanum were collected at Asubende and Agborlekame, both savannah villages. A range of species was caught in the Volta region (forest-savannah mosaic) and Gyankobaa (forest), with S. squamosum or S. sanctipauli being the predominant species, respectively. In Bosomase (southern forest region) only S. sanctipauli was collected in the 2009 wet season, but in the 2010 dry season S. yahense was also caught. MBRs ranged from 714 bites/person/month at Agborlekame (100% S. damnosum s.s./S. sirbanum) to 8,586 bites/person/month at Pillar 83/Djodji (98.5% S. squamosum). MBRs were higher in the wet season. In contrast, parous rates were higher in the dry season (41.8% vs. 18.4%), resulting in higher MPBRs in the dry season. Daily host-seeking activity of S. damnosum s.s./S. sirbanum was bimodal, whilst S. squamosum and S. sanctipauli had unimodal afternoon peaks. Conclusions: The bionomic differences between sibling species of the S. damnosum complex need to be taken into account when designing entomological monitoring protocols for interventions and parameterising mathematical models for onchocerciasis control and elimination

    Enhanced West Nile virus surveillance in the North Kent marshes, UK

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    Background As part of efforts to more fully understand the potential risks posed by West Nile virus (WNV) and Usutu virus (USUV) in the UK, and following on from previous reports of a potential bridge vector Culex modestus for these viruses, at wetland sites in North Kent, mosquito surveillance was undertaken more widely across the Isle of Sheppey, the Hoo Peninsula and the Kent mainland. Methods Larval surveys were conducted and Mosquito Magnet® adult traps were used to collect adult mosquitoes. Pools of female mosquitoes were tested for the presence of WNV using real-time reverse transcriptase polymerase chain reaction. A subset of samples was tested for USUV. Results Culex modestus was found in both the pre-imaginal and imago stage at all five locations surveyed, accounting for 90% of adult mosquitoes collected. WNV or USUV were not detected in any sample. Conclusions Although no mosquitoes have been shown to be virus positive, the field survey data from this study demonstrated the dominance of an important bridge vector species for WNV in this region. Its wide geographical distribution highlights the need to update risk assessments on WNV introduction, and to maintain vigilance for WNV in the South East of England

    A História da Alimentação: balizas historiográficas

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    Os M. pretenderam traçar um quadro da História da Alimentação, não como um novo ramo epistemológico da disciplina, mas como um campo em desenvolvimento de práticas e atividades especializadas, incluindo pesquisa, formação, publicações, associações, encontros acadêmicos, etc. Um breve relato das condições em que tal campo se assentou faz-se preceder de um panorama dos estudos de alimentação e temas correia tos, em geral, segundo cinco abardagens Ia biológica, a econômica, a social, a cultural e a filosófica!, assim como da identificação das contribuições mais relevantes da Antropologia, Arqueologia, Sociologia e Geografia. A fim de comentar a multiforme e volumosa bibliografia histórica, foi ela organizada segundo critérios morfológicos. A seguir, alguns tópicos importantes mereceram tratamento à parte: a fome, o alimento e o domínio religioso, as descobertas européias e a difusão mundial de alimentos, gosto e gastronomia. O artigo se encerra com um rápido balanço crítico da historiografia brasileira sobre o tema

    The Dodo and the Red Hen, A Saga of Extinction, Misunderstanding, and Name Transfer: A Review

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    The chronology of observations of two extinct flightless birds in 17th century Mauritius, the dodo (Raphus cucullatus) and the red hen (Aphanapteryx bonasia), and what names or descriptions were used for them, is re-examined. It was concluded that the balance of probabilities is strongly against birds called dodaarsen without descriptions in the 1680s being dodos rather than red hens. The dodo had disappeared earlier due to predation by pigs, but a hiatus in settlement broke observational continuity, yet folklore preserved the name and transferred it to the red hen. The dodo’s extinction thus happened unobserved

    Treasure Island: The rise and decline of a small tropical museum, the Mauritius Institute

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    Volume: 123AStart Page: 197End Page: 20

    Was the flying-fox Pteropus Comorensis on Mafia Island (Tanzania) introduced by Humans?

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    While there is no firm evidence either way, the fact of long cultural contact and that birds and lizards have been introduced by Comorians to Mafia and other East African islands, suggests that the flying-fox Pteropus comorensis is more likely to have been introduced to Mafia Island by humans than to have arrived there by itself as generally assumed.Keywords: Comoros, Zanzibar, Unguja, fruit-bat, Pteropus comorensis, trans-oceanicJournal of East African Natural History 100(1&2): 59–68 (2011

    Naming segregates from the Columba-Streptopelia pigeons following DNA studies on phylogeny

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    Volume: 125Start Page: 293End Page: 29

    Summer birds in Arkhangai pr ovince, Mongolia, July-August 2002.

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    A list of breeding birds for Tsetserleg and its surroundings is given for the first time, and additions are noted for the Khor go-T erkhiin Tsagaan Nuur National Park The presence of Eurasian Grif fons and Lammer geiers in the Khangai mountains is confirmed, and Black-headed Gulls suspected of breeding near Tsagaan Nuur , a new locality . An apparent marked increase in breeding/summering numbers of Tufted Duck and Velvet Scoter and a possible range expansion of Daurian Redstarts was noted. Mass mortality was observed in House Sparrows from eating moths
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