IPM of cockroaches Cockroaches

Public Health Significance of Urban Pests 67 Building practices, such as hollow-wall voids, drop ceilings and voids under cabinets, attics and built-in appliances, provide suitable harbourage for cockroaches. The elimi- nation of these harbourages is the primary goal of so-called built-in pest control or insect proofing. The use of inorganic dusts to eliminate cockroaches in harbourages and voids has long been advocated and is a successful means of controlling German cockroaches Ebeling, 1975. Inorganic dusts are preferred, because they retain their insecticidal acti- vity as long as the dust deposits remain intact and do not clump or cake. Repellent dusts, such as silica aerogel, are typically applied at the time of construction to prevent coc- kroaches from establishing themselves in wall and sub-cabinet voids. Non-repellent dusts, such as boric acid, are applied to existing infestations to provide remedial control. Non- repellent dust, however, will not scatter existing infestations. Non-repellent dusts should be routinely reapplied when flats are being refurbished to accommodate new occupants. One important advantage of built-in treatments is that the dusts are applied in areas not readily accessible to people and pets. Contrary to common belief, relative humidity does not strongly affect the toxicity of most insecticidal dusts, especially inorganic dusts. In fact, as boric acid dusts and silica aerogel dust plus synergized pyrethrin are wetted, their toxicity actually increases. In many cities throughout Europe and the United States, formerly state-owned and mana- ged housing projects are being converted into privately owned dwellings. These conver- sions present special problems in providing IPM programmes, because of the inability to inspect, monitor and treat all units within a building complex. In these units, inorganic dusts should be reapplied when flats are renovated between occupants. Community action plans and education programmes will be important in implementing IPM under these conditions. Also, cooperation is essential to ensure that all flats are treated.

2.6. IPM of cockroaches

Basic IPM programmes to control cockroaches were initiated in the 1980s and 1990s Robinson Zungoli, 1995. Unfortunately, as Robinson 1996a notes, “In spite of the need, the potential benefits, and sufficient development time, the concept of IPM has not been developed fully for household and structural pests.” Since these initial attempts, most of the research has focused on the reduction of cockroaches and allergens in struc- tures. Some pest control companies have incorporated baits into their cockroach control programme and simply renamed the service IPM. IPM programmes to control cockroaches are poorly understood. Even though 67.8 of pest management professionals PMPs thought that IPM was necessary to carry out their pest control mission, less than 25 felt that the average pest control professional unders- tood what IPM is. The PMPs also thought that there was no universal or clear definition of IPM in the industry Anonymous, 1995. The challenge is to provide effective and eco- nomical uses of pesticides and alternative technologies that control and eliminate pests in the living space Robinson, 1996a. The programmes must be economically and aes- thetically acceptable and must address specific attitudes of the target audience if they are to be successful Robinson Zungoli, 1995. Cockroaches 66 reported on a study of pregnant Latina women and their children in 644 homes in an agricultural community in Salinas Valley, California. These were mostly multiple dwel- ling units that were characterized by high residential densities 39 had more than 1.5 persons per room. In the United States, only 3 of Hispanic households and 0.5 of all households experience this level of crowding. About 60 of the Salinas Valley house- holds had cockroaches and 32 had rodents. The chances of having cockroaches increa- sed with the presence of peeling paint, water damage and high residential density. In New York City, the frequency of cockroach sightings and allergens is related directly to the level of housing problems and level of disrepair Rauh, Chew Garfinkel, 2002. Indicators of disrepair include holes in ceilings or walls, peeling paint, water damage, leaking pipes, and lack of gas or electricity in the past six months. In a study of asthma- tics from Connecticut and Massachusetts, low socioeconomic indicators and minority sta- tus were associated with a high likelihood of cockroach allergens in house dust Leaderer et al., 2002. Elevated cockroach allergen levels increased as the number of families living in habitations increased. In addition to the disrepair and poor sanitary conditions associated with poverty that pro- mote cockroach infestations, inner-city children are exposed to heavy applications of pes- ticides Landrigan et al., 1999. In 1997, the number of gallons of chlorpyrifos applied in New York City exceeded the total number of pesticides applied in any other county in that state. In housing projects in the East Harlem section of New York City, chlorpyri- fos, cyfluthrin and lesser amounts of bendiocarb were applied on a monthly basis. The use of illegal pesticides, such as aldicarb, Chinese chalk, and methyl parathion, is another problem encountered in impoverished neighbourhoods. The quality of the indoor environment is especially important, because 75 of children between the ages of 5 and18 years spend 16 hours or more in the home Bonnefoy et al., 2003. Consequently, conditions that contribute to cockroach infestations and control measures to eradicate them will greatly impact children living under conditions of poverty.

2.5. Impact of new housing technology