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In summary, the aims of this first component of IPM are to: • develop a site-specific inspection process
• conduct the inspection to determine the presence of insects and rodents.
15.1.2.2. Identification
The purpose of identification is to accurately identify pests and conditions that can sup- port pests present at a specific site.
The identification process is as follows. Insect and rodent specimens are collected and positively identified by field technicians, personnel with technical training or both.
Information about where the specimen was collected and signs of an active infestation are documented and used to aid positive identification. Pest-control measures should not
be implemented until a knowledgeable professional identifies the pest. Identifying the pest provides useful information about pest biology, preferred habitat and life-cycle. If
positive identification is not possible in the field, a trained technical expert examines spe- cimens. In addition, the field technician identifies conditions that support or encourage
pest activity; the goal is to identify the root causes of pests and their activity that can be corrected by different control measures, to provide a permanent solution to the existing
issue while acting to prevent infestations in the future.
In summary, the aims of this second component of IPM are to: • obtain positive identification of pests of concern at the site; and
• understand the biology of the identified pest and identify conditions conducive to the survival and growth of the pest population.
15.1.2.3. Establishment of threshold levels
T he purpose of establishing threshold levels is to provide a site-specific insect- and rodent-population level that can be tolerated on the basis of aesthetic, economic, legal
and health concerns. Control measures are implemented when the population exceeds the established threshold.
The process of establishing threshold levels is as follows. Information collected in the inspection and identification steps is used to determine population levels and set action
thresholds. When establishing a threshold, data on vector-borne infection and disease in the human population, along with information on the presence of pathogens in the rodent
and insect populations, should also be considered. Depending on local circumstances, the action threshold for pests with the potential to cause concern, transmit disease or cause
injury may be very low. For example, a single human case of HPS in an urban environ- ment may cause public concern and require the implementation of community-wide
control measures. It should be noted that in most settings where people are present, the tolerance of pests is zero, so the threshold level is one single specimen of a particular pest
species or population being considered. This is also true of heavily regulated industries, such as restaurants and food plants, where regulations prohibit any evidence of pests,
even if the pests have not infested human food.
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1992; United Nations Educational, Scientific and Cultural Organization, 1992; Mörner, Bos Fredrix, 2002; Dreyer et al., 2005.
WHO, through the adoption of World Health Assembly resolution 50.13 in 1997, called on Member States to “control vector-borne diseases through the promotion of integra-
ted pest management”. The concepts of IPM are part of the Global strategic framework for integrated vector management
WH O Strategy Development and Monitoring for Parasitic Diseases and Vector Control Team, 2004.
15.1.2. Components and tools of IPM
Pest control guidance developed by the United States Fish and Wildlife Service 2004 and the National Park Service 2004 describe IPM as “a science-based decision-making process
that coordinates knowledge of pest biology, the environment and available technology to prevent unacceptable levels of pest damage through cost-effective means, while posing the
least possible risk to people, resources and the environment” also see Kogan, 1998; AFPMB, 2003; Massachusetts Department of Food and Agriculture Pesticide Bureau, 2006.
The NPMA operationalizes IPM – that is, defines it so that it can be measured or expres- sed quantitatively – in five steps NPMA, 2006:
1. inspection 2. identification
3. establishment of threshold levels 4. employment of two or more appropriate control measures
5. evaluation of effectiveness.
15.1.2.1. Inspection
The purpose of inspection is to determine whether a current or potential insect or rodent infestation exists at a specific location.
The inspection process is as follows. The interior space and exterior envelope of buil- dings and all outdoor areas, including adjacent properties, are inspected to determine
whether an infestation or a potential for infestation exists. The location and scope of the infestation are determined in this step. Arthropod including insects- or rodent-related
structural damage or damage related to both groups and damage to equipment, sup- plies, stored items and food products are documented. Conditions that allow and sup-
port the presence of insect, rodent, or both types of pests, as well as the potential for nega- tive effects of pests, including public health considerations, are also documented. These
conditions may include a leaking water supply and wastewater drain lines, damp and wet areas, domestic animals, harbourage and coverage, avenues of entry, unsanitary
conditions, and access to food and water. The location, number and frequency of insect and rodent sightings by occupants and pest-control professionals are also documented.
This information is used to guide pest-control measures at a specific location. The infor- mation is collected and used to determine if mitigation is necessary to control an active
pest problem or to prevent a future infestation.
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15.1.2.5. Evaluation of effectiveness
The purpose of evaluating effectiveness is to determine whether the IPM plan was imple- mented as designed plan process objectives met and whether the objectives of the plan
were attained pest reduction and exposure objectives met.
The process of evaluating effectiveness is as follows. The evaluation determines how effective the implementation of each of the first four steps has been. The process used to
implement each step is described and evaluated to determine if any phase of the IPM plan could have been implemented with greater efficiency and effectiveness. The lessons
learned from the evaluation are documented and used to improve the implementation process.
The methods used to evaluate the reduction of pest activity and exposure are determined and executed at the beginning of the IPM process. During implementation of the first
four steps – inspection, identification, establishment of thresholds and employment of control measures – monitoring surveys are conducted to document pest numbers, pest
activity and opportunities for human–pest interaction. These surveys determine whether the pest population has been reduced below the site-specific threshold level pest reduc-
tion and exposure outcomes. Examples of pest and exposure reduction indicators include: frequency, number and time of visual sightings; insect activity following aerosol flushing;
pests counts obtained from vacuuming; positive bait stations; flea egg counts; presence of rodent and cockroach droppings; positive sticky and snap traps; mosquito larval dipper
counts, adult trapping counts, and adult landing and bite counts; tick counts; signs of rodent gnawing and food contamination, number of active burrows, runways and the
presence of rodent tracks. The survey information is used to identify causative factors that have not been fully addressed during implementation. The evaluation of the effec-
tiveness step documents the attainment of the process and pest reduction objectives esta- blished in the IPM plan.
In summary, the aims of this last component of IPM are to: • evaluate the outcome of the interventions implemented and determine whether the pro-
cess and pest reduction objectives have been achieved; and • document actions and decisions and maintain clear and detailed records.
15.1.2.6. Develop an IPM plan
