Irwin H. Gilbert

Attractiveness of men and women to Aedes aegypti and relative protection time obtained with deet.

Tests were conducted with 100 men and women subjects to compare their attractiveness to the yellow fever mosquito, Aedes aegypti (L.), and in addition to compare the times of protection against the mosquito when the same group of subjects was treated with deet. In previous experiments reported by Smith et al. (1963), Gouck and Bowman (1959), and Gouck and Gilbert (1962), only three to five test subjects were used. Our tests, however, were conducted with 50 subjects of each sex. Such factors as sex, age, weight, skin temperature, moisture output, and color were investigated to determine their influence on both attractiveness and protection time. Statistical significance of the values obtained was determined for the differences among individuals of the group and for the differences between men and women. In addition 37 women with menstrual cycles were tested before and after menses to determine the effects of physiological changes on the attractiveness of the subjects to the mosquito.

Evaluation of (Z)-9-Tricosene for Attractancy for Musca Domestica in the Field

The house fly pheromone (Z)-9-tricosene (muscalure), was evaluated against Musca domestica L. at dosages of 125, 25, 5, and 1 mg in combination with sugar fly bait containing trichlorfon. The highest dosage tested (125 mg) was the most attractive to both males and females in a natural population at a swine farm in northern Florida. Significant differences occurred between dosages, each being less effective as the dosage decreased. The 5-mg dose was field tested at heights of 1, 3, and 5 ft above the ground. The largest number was captured at the 1-ft level, but the degree of attraction was relatively small. No significant difference was apparent in the numbers of males and females captured. The response of released adults from a genetically engineered male-producing strain was greater than the response of released adults.

Comparison of Four Cinchoninates, an Oxetanone, and Two Standard Skin Repellents against Aedes Aegypti and Stomoxys Calcitrans

Five compounds (50% solutions in ethanol) were evaluated as skin repellents against caged Aedes aegypti (L.) and Stomoxys calcitrans (L.) by comparing the protection times obtained with the protection times obtained with 2 standard repellents, deet (25% solution in ethanol) and dimethyl phthalate (50% solution in ethanol). Against mosquitoes, the deet was significantly more effective than the candidate compounds or than dimethyl phthalate, and dimethyl phthalate was equal in effectiveness to the 4 cinchoninates and was less effective than 4-pentyl-2-oxetanone, which had a disagreeable odor. In the tests with Stomoxys calcitrans, 4-pentyl-2-oxetanone as a 50% solution in ethanol was more effective than deet and the other repellents; also, ethyl 3-ethylcinchoninate and butyl 3-methylcinchoninate as 50% solutions were about as effective as deet, buy ethyl 3-methylcinchoninate was only about half as effective as deet, and propyl 3-methylcinchoninate and dimethyl phthalate were the least effective.