What is the role of non-chemical controls in Integrated Vector Management (IVM)?

• A. They replace all chemical control measures.
• B. They are too costly to implement.
• C. They reduce reliance on chemicals and can slow resistance when used with other tools.
• D. They have no impact on disease transmission.

Answer: (C)

In Integrated Vector Management, the goal is to use a mix of complementary strategies rather than depend on a single method to control mosquitoes. Non-chemical controls fit this approach by targeting mosquitoes in different ways and at different life stages, often with fewer downsides than relying only on pesticides.

They are the best choice here because they reduce how much chemical insecticide is needed and, when used together with other tools, slow the development of resistance. By removing or altering mosquito breeding sites, introducing natural predators, improving housing and environmental conditions, and using physical barriers, the overall pressure on mosquitoes is reduced. This diversification makes it harder for mosquitoes to adapt to any one method and helps sustain control efforts over time.

Examples include eliminating standing water and other breeding habitats, habitat management, using larvivorous fish or microbial larvicides like Bti, and installing physical barriers such as screens or proper water storage that limit mosquito opportunities to breed or bite. These approaches can be cost-effective in the long run and often involve communities, which strengthens and sustains control.

Non-chemical controls do not replace chemical measures entirely, and they do have an impact on disease transmission by lowering vector populations and biting rates, contributing to fewer cases.