The discovery and distribution of Aedes albopictus in Harris County, Texas.

On August 2, 1985, numerous adults and larvae of an unknown species of Aedes were collected from several widely separated tire dumps, in and around the city of Houston, Texas. Specimens sent to Dr. Y.-M. Huang at the U. S. National Museum, were identified as Aedes albopictru (Skuse), a container-breeding species, indigenous to the Oriental and Australian regions. Aedes albopictu.r has been collected three times previously in the United States (Pratt et al. 1946, Eads 1972, Reiter and Darsie 1984), but this is the first record of breeding populat ions establ ished in the continental United States. A survey of Harris County was begun on August 22 to determine the frequency, abundance and distribution of Ae. albopictus in water-filled cbntainers, especially tires. Organization of the survey was based upon the coded system of sectors used by the Harris County Mosquito Control District to identify specific regions within the county. Under this system, Harris County is divided into 268 sectors' averaging 6.6 square miles. OnceAe. albopictus was found breeding on a site, we considered the entire sector in which the sample was taken to contain Ae. albopicnu. We then proceeded to survey the next successive sector. In this way, the 1,765 square miles of the county could be surveyed in a minimal amount of time. The survey was completed on October ll, with 178 (66.4Va\ of the sectors from all parts of the county being investigated. Twenty-three water-filled containers and 166 used tires were found with mosquito larvae of 8 different species (Table l). Surprisingly, Ae. albopictus was both the most abundant and frequently collected species. Aedes albopicrur was found in 125