To prevent mosquitoes from spreading, the first step you need to take is to destroy their potential breeding places for the mosquitoes. Mosquitoes thrive in environments comprising of stagnant water sources. Clear off all sources of standing water including barrels, vases, basins or even cups and unused tires. If there remains a stagnant water source for over a week, there are high chances of mosquitoes inhabiting. Also, ensure that sewage and drainage systems are well covered at all the times.