Origin and expansion of the mosquito Aedes aegypti in Madeira Island (Portugal).

Historically known as the yellow fever mosquito, Aedes aegypti invaded Madeira Island in 2005 and was the vector of the island's first dengue outbreak in 2012. We have studied genetic variation at 16 microsatellites and two mitochondrial DNA genes in temporal samples of Madeira Island, in order to assess the origin of the invasion and the population structure of this mosquito vector. Our results indicated at least two independent colonization events occurred on the island, both having a South American source population.

Aedes aegypti on Madeira Island (Portugal): genetic variation of a recently introduced dengue vector.

The increasing population of Aedes aegypti mosquitoes on Madeira Island (Portugal) resulted in the first autochthonous dengue outbreak, which occurred in October 2012. Our study establishes the first genetic evaluation based on the mitochondrial DNA (mtDNA) genes [cytochrome oxidase subunit I (COI) and NADH dehydrogenase subunit 4 (ND4)] and knockdown resistance (kdr) mutations exploring the colonisation history and the genetic diversity of this insular vector population. We included mosquito populations from Brazil and Venezuela in the analysis as putative geographic sources.

The association of Triatoma maculata (Ericsson 1848) with the gecko Thecadactylus rapicauda (Houttuyn 1782) (Reptilia: Squamata: Gekkonidae): a strategy of domiciliation of the Chagas disease peridomestic vector in Venezuela?

Objective: To investigate the bioecological relationship between Chagas disease peridomestic vectors and reptiles as source of feeding.

Methods: In a three-story building, triatomines were captured by direct search and electric vacuum cleaner search in and outside the building. Then, age structure of the captured Triatoma maculata (T.

Neurotoxic activity and ultrastructural changes in muscles caused by the brown widow spider Latrodectus geometricus venom.

Brown widow spider (Latrodectus geometricus) venom (BrWSV) produces few local lesions and intense systemic reactions such as cramps, harsh muscle pains, nausea, vomiting and hypertension. Approximately 16 protein bands under reducing conditions and approximately 14 bands under non-reducing conditions on a 12.5% sodium dodecyl sulfate-polyacrylamide gel electrophoresis were observed.

Stridulatory sound emission of Panstrongylus rufotuberculatus Champion, 1899, (Hemiptera: Reduviidae: Triatominae).

This study contains the first report of stridulatory sound observed in Panstrongylus rufotuberculatus Champion, 1899, and also a new record of this species in Venezuela. The conditions in which stridulation occurred are described, as well as the general environmental characteristics of the localities where it was found. This triatomine only performs the sound in conditions of extreme provocation.

A preliminary study of haemolymph from four Venezuelan populations of Panstrongylus geniculatus Latreille, 1811 (Hemiptera: Reduviidae) and its epidemiological significance.

SDS-PAGE profiles of both sexes of the haemolymphs of Panstrongylus geniculatus from different Venezuelan regions (savannas, piedmont, tropical forest and urban areas) were compared. It was determined that the haemolymphs showed a different electrophoretic profile, with proteins that ranged from 14 to 164 kDa. The most representative protein band in the profile of females was observed in two sectors: between 164 and 46 kDa and between 33 and 30 kDa.

Severe human urticaria produced by ant (Odontomachus bauri, Emery 1892) (Hymenoptera: Formicidae) venom.

Background: Ant sting reactions are becoming an increasing problem in tropical countries. It is important for physicians to be aware of their possible cutaneous and systemic manifestations.

Methods: A child with a severe allergic reaction to an ant sting was examined and is discussed.