摘要：

In most of the 130 islands of French Polynesia, the stenotopic mosquitoes Aedes aegypti (the main local vector for the viruses causing dengue) and Aedes polynesiensis (the main local vector of Wuchereria bancrofti) share many breeding sites in water containers such as discarded cans, coconut shells, buckets and water-storage pots and drums. In addition to selective application of insecticides, non-polluting methods of controlling these mosquitoes have been evaluated during the last decade in two main ecological situations: (1) villages, where Aedes breeding sites are typically peridomestic; and (2) flooded burrows of land crabs, the major source of Ae. polynesiensis throughout the South Pacific region. Large-scale trials of biological control agents, such as mosquito fish (Gambusia affinis and Poecilia reticulata) and copepods (Mesocyclops aspericornis), and of integrated-control strategies have demonstrated the efficacy of certain techniques and control agents against the target Aedes populations in some village situations. Generally, mechanical methods (the use of layers of polystyrene beads against mosquito larvae and pupae, and screening against adult mosquitoes) were more efficient than use of the biological control agents. By integrating several methods of control, mosquito densities (as measured by human-bait collections and larval surveys) were reduced significantly compared with the results of concurrent sampling from untreated villages, and control remained effective for months after the interventions ceased. In land-crab burrows, the first attempts to control Aedes larvae used bacterial agents (Bacillus thuringiensis) and predatory copepods gave disappointing results. Mesocyclops aspericornis could be an effective control agent if the burrows were constantly flooded, but most burrows dry out and refill periodically, so copepod populations do not survive. As it proved difficult to reach all corners of the long sinuous burrows with any control agent,...

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