Flea exclusion and physical removal Pesticide applications for flea control

Public Health Significance of Urban Pests 165 ted with fleas and only 10 of rural opossums carrying fleas Dryden et al., 1995. Rodent-proofing buildings and landscape modifications should be implemented to ensure the habitat is unsuitable for rodents and their fleas. Exclusion measures and sanitation practices prevent rats and other small mammals from dwelling near or entering buil- dings. By denying them food, water and harbourage, rodents and their ectoparasites can be eliminated from a neighbourhood.

5.7.3. Flea exclusion and physical removal

Host exclusion from the property, especially preventing access to crawl spaces beneath homes, is the most important means of excluding the fleas they carry. Pest-proofing homes also requires conscientious inspection of access points, to identify openings through which arthropods can gain access to the building, so that they can be sealed as well. Flea traps can be effective in monitoring flea populations and in confirming infestations Dryden Broce, 1993. However, trapping rarely reduces population size enough to serve as a significant component of an IPM programme. Fleas can be physically removed from a cat or dog by using a flea comb. These devices are designed with closely spaced teeth so that, as the comb is drawn through the coat, fleas become entrapped and can be removed. The successful use of flea combs depends on ani- mal tractability, coat thickness and length, and user patience and persistence.

5.7.4. Pesticide applications for flea control

In California, plague control operations are conducted by public health agencies and typi- cally involve the use of insecticides to reduce rodent flea populations in localized areas. Usually, insecticidal dust is applied in and around rodent burrows so that, as rodents enter or exit these treated burrows, adherent residues are transferred to nest material where the majority of adult and immature fleas are found Gerry et al., 2005. This technique ensures that small quantities of insecticide are optimally targeted to reduce flea numbers over a large geographic area. Control measures for plague and murine typhus should first focus on fleas and subse- quently on their rodent hosts. Indiscriminate elimination of rodents creates greater risk, since their ectoparasites the pathogen vectors immediately seek other hosts – among them people – and transmit infections to them, as may happen potentially with plague and rickettsioses. Flea suppression should therefore precede rodent baiting by at least a week WHO, 1998. Insecticides, IGRs, or both should be applied to rat pathways, nests and holes Mian et al., 2004. Rats should then be eliminated using traps or rodenticides after the flea population is decreased. If separate treatments for rodents and ectoparasi- tes are not practical, an alternate method is to dust runways and apply poison baits at the same time. This method works well only with slow-acting poisons such as anticoagu- lants so that ectoparasites are killed before rodents succumb to the rodenticide. Fleas 164 risk to human health. Flea suppression that targets hosts should be initiated before attempts to eliminate rodents, to prevent flea problems rebounding after host removal. The control of ectoparasites must be integrated with rodent control, in combination with ongoing and sustained habitat modification. In urban areas, government agencies bear responsibility for managing wildlife and feral animals, to prevent their ectoparasites from infesting domestic pets. Likewise, munici- palities have codes that regulate sanitation, debris accumulation and other conditions that affect rodent populations. Budgets for code enforcement, related maintenance activities and municipal pest control services vary widely by jurisdiction, as does emphasis on such expenditures.

5.7.1. Flea inspections and detection