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Biomedical subjects

W MATHIS

Publications and source records attributed to W MATHIS.

13 recordsLinked to original sources
PubMed1963

DICHLORVOS AS A RESIDUAL FUMIGANT IN MUD, PLYWOOD AND BAMBOO HUTS.

In experiments conducted at Savannah, Ga., dichlorvos dispensers of montan (lignite) wax installed at a rate of six units per 1000 cubic feet (28 m(3)) in huts with mud or bamboo walls and with thatched roofs produced kills of caged Anopheles quadrimaculatus (12 hours' exposure) at or above 95% for 5-6 weeks. The doors, windows, and eaves of the huts were open for maximum ventilation. In a non-ventilated plywood hut, a single dispenser gave effective kills for 7 months but in a non-ventilated mud hut the period was 5 months. Air concentrations of dichlorvos in the mud hut were shown to be definitely lower than those in a plywood hut at the same dosage level.

Animals↗
PubMed1963

INITIAL FIELD STUDIES IN UPPER VOLTA WITH DICHLORVOS RESIDUAL FUMIGANT AS A MALARIA ERADICATION TECHNIQUE. 2. ENTOMOLOGICAL EVALUATION.

In mud houses in Wakara, Upper Volta, dichlorvos dispensers installed at the rate of one dispenser per approximately 500 cubic feet (14 m(3)) produced 70% or higher average kills of adult Aëdes aegypti, exposed overnight in screen wire cages suspended at levels of 6 feet (1.8 m) and 2 feet (0.6 m), for approximately three months during the wet season and four months during the dry season. Average kills of 96% and 80% were obtained in the dry season at the 6-foot and 2-foot levels, respectively, with 6-hour daytime exposures 17-22 weeks after treatment.

Aedes↗
PubMed1961

Field tests on the residual effectiveness of deposits of malathion and Bayer 29493 against resistant Anopheles albimaus in El Salvador.

The appearance of resistance to both dieldrin and DDT in several malaria vectors has intensified investigations on the potential of organophosphorus compounds for residual application. This report describes the final year's activities of a three-year study on malathion. Water-wettable formulations of malathion and of Bayer 29493 were evaluated against DDT/dieldrin-resistant Anopheles albimanus in El Salvador.The results indicate that neither compound at a dosage of 0.5 g/m(2) offers any promise as a residual agent. At dosages of 1.0 g/m(2) or 2.0 g/m(2) the two toxicants gave effective kills (70%-100%) for periods of 21/2-3 months, based on 1-hour exposure to the treated surfaces. Up to 3 months, both compounds gave similar levels of effectiveness on wood, thatch, and mud. On whitewash and plaster surfaces, Bayer 29493 was superior to malathion.The findings indicate that each insecticide has considerable potential value for residual treatment in areas where the malaria vector cannot be killed effectively by either DDT or dieldrin. In such areas, further investigation into their utility as replacements for the chlorinated hydrocarbon insecticides is warranted.

Animals↗