Nuisance provisions of the Public Health etc (Scotland) Act 2008: guidance

SECTION 5 - COCKROACHES

Classification

There are three main pest species: the American ( Periplaneta americana), German ( Blattella germanica) and Oriental ( Blatta orientalis) Cockroaches. The German and Oriental species are common in the UK.

Habitat

Cockroaches are nocturnal and they prefer warm dark spaces. Cockroaches are highly adaptable and extremely mobile, moving into new buildings via sewer pipes, ducts etc. The Oriental cockroach is the most common and largest of the two and can climb rough surfaces and will congregate around water sources. The German cockroach is smaller, but is able to climb vertical smooth surfaces.

Health Impact

Cockroaches can cause allergic reactions in susceptible individuals (e.g., asthmatics) and individuals exposed to infestations for long periods of time. Their presence may cause an occupier distress. They can contaminate a range of stored food products.

Nuisance

It is essential to identify the species and determine the extent and severity of the problem. The presence of cockroaches within premises has a significant emotional effect particularly as they are considered to be an indication of unsanitary conditions. In general, in domestic premises, it is likely that the threshold will be very low and control actions might be taken in cases of a few cockroaches.

Assessment

It is essential to identify the locations where cockroaches are breeding or gaining access to structures. The use of traps is important in determining the extent and severity of the problem. Trap counts provide a quantitative mechanism upon which to base treatments and evaluate the success of the control measures. Trapping can also reduce unnecessary treatments and thereby reduce the amount of insecticides applied.

Controls

Prevention - cracks in walls, floors and ceilings or inaccessible voids between and behind equipment should be eliminated as these areas provide harbourage. Also the potential for movement across common pipes and conduits should be eliminated.

Cleaning and sanitation - in addition to removing harbourage sites, sources of food and water should also be eliminated.

Insecticides - insecticidal sprays, dusts and gel baits should be applied to cracks, crevices and voids where cockroaches harbour. Non-repellent insecticides should be used to avoid scattering cockroaches and slow-acting baits might be used indoors whenever possible to improve the control of early instars.