Amends the Mosquito Abatement District Act. Provides that the board of trustees of a mosquito abatement district shall have power to take all necessary or proper steps for the surveillance, monitoring, and extermination of mosquitoes, flies, ticks, and vectors within the district (rather than for the extermination of mosquitoes, files and other insects within the district), and, subject to the paramount control of the municipal or other public authorities, to abate as nuisances all stagnant pools of water and other breeding places for mosquitoes, flies, ticks, and vectors (rather than mosquitoes and other insects) within the district. Provides that a district may annex territory by ordinance whenever a mosquito abatement district operating within territory predominantly in a municipality or 2 or more municipalities that would become coterminous or nearly coterminous with the municipality or municipalities upon the annexation of additional territory within the municipality or municipalities (rather than whenever a mosquito abatement district contains over 90% of territory of a specific city or village, the mosquito abatement district may annex additional adjacent and contiguous territory within that city or village). Requires the ordinance to describe the territory annexed together with an accurate map of the annexed territory and that, if the ordinance becomes effective 30 days after the date of publication or is approved by referendum, a copy of the ordinance shall be filed in the offices of the county clerk and recorder of each county in which the annexation takes place. Removes a prohibition to annexing territory until more than one year after territory has first been included in a municipality unless the territory annexed is 50 acres or less. Makes other changes.