Control of Mosquitoes in the United States

The recent emergence and spread of West Nile virus in the United States has rekindled an awareness of mosquitoes as a public health issue. Nonetheless, sheer numbers of mosquitoes have plagued their victims in North America from time immemorial. Native American tribes were known to migrate seasonally from the eastern coastal areas to the highlands miles inland to escape the hordes of mosquitoes emerging from the salt marshes. Inland, the problem was only marginally better. Indeed, in his diaries, the great explorer Meriwether Lewis spoke at length of the mosquito pestilence to be encountered in the pristine interior wilderness of what was to eventually become the United States. Since the discovery by Sir Ronald Ross in 1897 that mosquitoes transmit malaria, the control of mosquitoes in the United States has assumed a significance far beyond reduction of a summertime nuisance. No longer would devastating outbreaks of Malaria, Yellow Fever and Dengue Fever in the United States and elsewhere go unchallenged due to ignorance of their means of transmission. Realizing there now existed a means to obtain a measure of public health protection heretofore unavailable, citizen groups in the early 20th Century began conducting referenda to establish special taxing districts to fund the first organized mosquito control activities in California, New Jersey and Florida. Others followed suit as the need was recognized and the funding allowed. In the ensuing years, mosquito control personnel refined their methods through applied research and assisted federal and state agencies in developing certification criteria to ensure conformance to stringent safety standards. The result – what we believe to be the most technically proficient, professional mosquito control agencies in the world. The circumstances necessitating formation of mosquito control programs in the United States are unique for each jurisdiction in terms of available resources, topography, hydrology, and the bionomics of the mosquito species to be controlled. For this reason, considerable judgment must be exercised in allocation of limited resources to extract the maximum benefit for both the citizenry and the environment. At present, there are at least 734 organized mosquito control districts conducting mosquito control activities in the United States. These formally recognized districts can serve an area as small as 2 square miles and a population of 300 up to well over 3000 square miles with populations of 5 million. At least 1105 small municipal agencies, mostly in rural areas, conduct mosquito control activities in some measure. Annual budgets can run from as little as $500 to as much as $24 million. Total expenditures for mosquito control by local government entities in the United States are in the area of $200 million, but tend to fluctuate with revenues. Funding for these comes from a variety of sources, e.g. special county/municipal tax levies, property assessments, distributions of state taxes and federal grants.