Sewage Breeds Bigger Mosquitoes

New research has shown that mosquitos that breed in sewage-contaminated streams are bigger and faster than those who have bred in cleaner waters.

The new findings are a cause for concern for certain regions in America which use a sewage overflow system. Under normal circumstances, storm run-off is mixed with a lightly treated wastewater before being delivered to a sewage treatment plant. However when there is a huge storm, the contents of the pipes bypass the facility and flow direct into rivers and lakes. This system is used in several areas, mainly in older cities in the northeast and midwest of America.

The researchers compared mosquitos which grew in tanks holding polluted water versus those in tanks with clean water. The results found that mosquitoes in the polluted water tanks hatched from their eggs more quickly and were more likely to survive than those in the clean water.

Polluted water and sewage often contains ammonia phosphates and these feed bacteria and micro-organisms which mosquitos feed on. Fish tend not to be able to live in polluted waters therefore the mosquitos have fewer predators.