Pesticide exposure and risk

Because flea larvae can occur in carpeted areas of buildings, general carpet treatment is frequently undertaken to eliminate them. This tactic involves treating large indoor areas with pesticides, which may result in human exposure (Koehler & Moye, 1995). To mini-mize this risk, reduced toxicity compounds, such as IGRs, are promoted.

Because pets share human living quarters, they bring people into contact with the ani-mal’s ectoparasites and with residual insecticides used to treat them for fleas. While eli-mination of fleas from the pet is desirable, the products used on the animal must have low mammalian toxicity to minimize risks to pets and people. As with all pesticidal treat-ments, the applicator is likely to contact the most concentrated material, so manufactu-rers have developed packaging for host-targeted products (individual vial applicators), to reduce human exposure and protect consumers.

5.9. Benchmarks

Larvicides (especially IGRs) may be employed prophylactically to suppress fleas, but generally environmental flea control is undertaken when adult fleas are detected by a home’s occupants (Hinkle, 2003). In warm regions, pets may be maintained on flea pre-ventatives year-round, but veterinarians in cooler climates typically recommend on-host products be used during the months when flea exposure is likely.

While the action threshold for cat flea control is based on human annoyance, in situa-tions of potential zoonotic disease outbreaks, rodent fleas must be actively monitored and the risk assessed to trigger control interventions. In cases involving imminent disease transmission, immediate and comprehensive flea suppression should be initiated. Due to the risk of fleas moving from dying hosts to people, rodent control must be coordinated with flea control.

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