What factor most contributes to the spread of mosquito-borne diseases?

The spread of mosquito-borne diseases is significantly influenced by urbanization and the presence of standing water. Urban areas often create environments that are conducive to mosquito breeding. As cities expand, they can inadvertently generate more stagnant water bodies through construction sites, clogged drainage systems, and artificial water features. Mosquitoes typically lay their eggs in standing water, making these areas ideal breeding grounds.

Additionally, urbanization tends to alter natural ecosystems, reducing predators and competitors that might control mosquito populations. The combination of increased human density and standing water enhances the chances of mosquitoes coming into contact with people, thus facilitating the transmission of diseases such as West Nile virus, Zika virus, and dengue fever.

While humidity can influence mosquito activity, it is not as direct a factor in disease spread compared to the creation of breeding sites through urbanization. Recycling practices and pollution may have environmental impacts but do not directly create the breeding conditions that lead to increased mosquito populations as significantly as urbanization and standing water do.