Firstly, there are many reasons can cause eye infection, including, bacterial, viral or fungal agents. In addition, all parts of your eyes also will make your eyes infected. So, once one part of your eyes is affected, your eyes will be infected. What's more, if you wear contact lens, it is easier to get eye infection. As a result, although you was cured, you still can get infected. To avoid this situation again, you can follow the following advices. First, wash your hand often and carefully. Second, do not share personal stuff, such as contact lens, make up, towels, eye medicine, etc. Third, wear goggles when stay in harsh environments. Forth, tell your eye doctor when your eyes is uncomfortable.