Maps provide information for field survey and control activities, program evaluation, and reporting and budgeting purposes.
A. Maps are used for orientation, for locating and plotting larval breeding places and adult sampling stations, for plotting rainfall data to determine floodwater species emergence, to keep track of premises inspected and to locate areas of active viral transmission.
B. The plotting of weekly or biweekly counts of larvae and adults at sampling stations indicate at any given time the abundance of mosquitoes, species involved, possible flight range from breeding sites and habitats, and disease potential. This information identifies areas requiring high priority for treatment.
C. Global Positioning Systems (GPS) compute the longitude, latitude and altitude of any point on the Earth's surface using a satellite-ranging technique. GPS coordinates are reliable for accurate location of sampling stations and areas of interest. GPS tracking capability makes field recording processes more efficient.
D. Geographic Information Systems (GIS) are computer-based systems capable of assembling, storing, manipulating, analyzing and displaying data identified by their geographical coordinates (spatial reference). Spatially referenced data from various sources can presented in the form of maps.
1. Maps are used to present and aid in analyses of information on the spatial distribution of mosquito breeding sites, species diversity, flight ranges and location of positive mosquito-borne disease cases or clusters.
2. GIS tools aid in making spatially informed decisions to improve resource allocation for mosquito control.
3. In combination with GPS tracking systems, GIS can be used to monitor insecticide applications and personnel, to create simple routes and assignments.
4. Remote sensing (such as satellite images and aerial photography) data can be analyzed with GIS to accurately identify and map potential mosquito-breeding habitats and to predict increases in mosquito populations.
1. Inspector(s) should routinely record geographic information such as location of sampling sites (recorded with the aid of GPS or indicated on road maps) while performing mosquito surveillance activities.
2. The person designated to supervise nighttime spraying should monitor personnel while in the process of applying insecticides when adulticiding is warranted.
3. Ideally, a person with data management experience, geography and GIS training should manage the data. A computer-literate person may be trained for computer operations with hardware-software applications of GIS.
4. GIS technology is a cost-efficient method that can be used to estimate the areas to be treated.
a. It provides a digital record of all activities (using GPS tracking devices on trucks and aircraft), which allows for auditable treatment of the data and accountability of operation.
b. High-quality, high-resolution aerial photography can be used to dramatically reduce the number of man hours in the field, by giving visual access to areas not easily available because of road limitations, vegetative cover or terrain features.