Browsing by Autor "CJ Schofield"

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Chagas disease vector control in Central America
(Elsevier BV, 1997) CJ Schofield; JP Dujardin
Chagas Disease Vector Control in Tupiza, Southern Bolivia
(Instituto Oswaldo Cruz, Ministério da Saúde, 1997) Gleberson Guillen; Ricardo Andrés Caicedo Díaz; A Jemio; J Alfred Cassab; Cláudio Teixeira Pinto; CJ Schofield
Heavy domestic and peridomestic infestations of Triatoma infestans were controlled in two villages in southern Bolivia by the application of deltamethrin SC25 (2.5% suspension concentrate) at a target dose of 25 mg a.i./m2. Actual applied dose was monitored by HPLC analysis of filter papers placed at various heights on the house walls, and was shown to range from 0 to 59.6 about a mean of 28.5 mg a.i./m2. Wall bioassays showed high mortality of T. infestans during the first month after the application of deltamethrin. Mortality declined to zero as summer temperatures increased, but reappeared with the onset of the following winter. In contrast, knockdown was apparent throughout the trial, showing no discernible temperature dependence. House infestation rates, measured by manual sampling and use of paper sheets to collect bug faeces, declined from 79% at the beginning of the trial to zero at the 6 month evaluation. All but one of the houses were still free of T. infestans at the final evaluation 12 months after spraying, although a small number of bugs were found at this time in 5 of 355 peridomestic dependencies. Comparative cost studies endorse the recommendation of large-scale application of deltamethrin, or pyrethroid of similar cost-effectiveness, as a means to eliminate domestic T. infestans populations in order to interrupt transmission of Chagas disease.
Changes in the Sexual Dimorphism of Triatominae in the Transition from Natural to Artificial Habitats
(Instituto Oswaldo Cruz, Ministério da Saúde, 1999) JP Dujardin; Mário Steindel; T. Chavez; M. Machane; CJ Schofield
A shift from large to small average sizes was observed in Triatoma infestans and Rhodnius domesticus between field and domestic (or laboratory) conditions of life. It was more pronounced in the female specimens, leading to a subsequent reduction of sexual size dimorphism. This feature is discussed in terms of genetic and populational changes occurring from natural to artificial habitats, in particular those related to population densities. Sexual size dimorphism is then recommended as a new character to be used in the study of species of Triatominae adapting to domestic ecotopes.
The process of domestication in triatominae
(Instituto Oswaldo Cruz, Ministério da Saúde, 1999) CJ Schofield; Liléia Diotaiuti; JP Dujardin
The use of morphometrics in entomological surveillance of sylvatic foci of Triatoma infestans in Bolivia
(Elsevier BV, 1997) Jean‐Pierre Dujardin; Harry Bermudez; CJ Schofield