For effective insect repellent, there tends to be two choices. The first is the most common and widely recognized effective repellent commonly known as DEET. The second would be an "all-natural" solution that does not have the long and well documented history of effective use that DEET based solutions have.
With mosquito born diseases like Zika becoming more of a threat each day, it would serve you well to chose the most effective insect repellent you can purchase. This US Army Type Inspect Repellent balances concerns about 100% DEET by reducing the level of concentrate to 30% which has been shown to be effective and safe to use for long periods of time. No other insect repellent is as effective as DEET based solutions like this US Army Type Insect Repellent.