Observations on container-breeding mosquitoes in New Orleans, Louisiana, with an estimate of the population density of Aedes aegypti (L.).

In a survey of containers infested with Aedes aegypti (L.) conducted during September and October 1979 in a substandard residential area of New Orleans, LA, infestation indices were as follows: House--35, Breteau (foci)--85, Receptacle--69, Block--100, and Larval Density--169. A mean of 48.5 water-holding containers were found per block. More than 50% of these receptacles were narrow-mouthed containers, e.g., drink bottles, that held an average of less than 0.03 mosquito immatures each. After exclusion of data on the unproductive narrow-mouthed type, the average container held 7.8 liters of water, 105 1st and 2nd instars, 69 3rd an 4th instars, and 12 pupae. With assumed constant adult survival rates of 0.85-0.90 per day, the number of females per block on any particular day was estimated from pupal production data at 362-558, and the standing crop of females 12 days and older and therefore old enough to transmit dengue fever if they are vector competent was estimated at 51-158 per block.