Public Health & Vector Control: IRS, Space Sprays and Baiting

Public-health pest control splits into residual surface treatment, space treatment and baiting. Indoor residual spraying (IRS) against malaria mosquitoes relies on long-residual pyrethroids such as deltamethrin WP and lambda-cyhalothrin CS, applied to interior walls where mosquitoes rest; provincial health departments tender these by the kilogram and litre each season.

Space treatment — ULV cold fogging and thermal fogging — knocks down flying adults with fine droplets of pyrethrin/pyrethroid or malathion formulations (Deltacide, mercaptothion ULV). Machines such as the Hornet ULV apply these at very low volume per hectare.

Baiting exploits social behaviour: imidacloprid and fipronil gels (Domino class) for cockroaches, fipronil granules (Optima class) for ants, and fly baits combining imidacloprid with attractants (Snap Fly Bait, Fly-Tac). Baiting achieves colony-level control at very low chemical loading — the preferred approach in food premises.

Safety discipline is non-negotiable: pyrethroids are devastating to aquatic life, OPs require cholinesterase-awareness for handlers, and all structural work needs the PPE range — nitrile gloves, respirators with A2B2 filters, coveralls — that MedQ stocks alongside the chemistry.