Many local governments take an active role in preventing mosquitoes and the dangers associated with them through regular spraying of parks and other public places. You can do your part to help minimize the likelihood of an infestation by keeping an eye out for standing water around your home or yard. Check out this study done by the NPMA, the results are a must see:
Clean up quickly after storms and rainy seasons and do not allow debris to accumulate, which can trap water in crevices. Clean gutters out frequently, repair leaky faucets and pipes and fill in any ditches where puddles exist. Make sure windows and doorways around your home are well sealed to prevent mosquitoes from getting inside and use screens in warmer weather.
When outdoors, use a bug repellant to protect yourself from being bitten. Be particularly cautious in wooded areas and near streams. If sitting outside at night, consider lighting candles or building a fire, which may help keep mosquitoes at bay. If hiking, wear long sleeves and pants. Make sure your pets are getting preventative treatment to protect them against mosquito bites and the illnesses they can cause.