The best thing to do is to bring one of your plants into the extension office. In order to see what is really going on we need to see more than the picture sent. Some soil from around the roots would also be helpful. The most active office for your home gardening needs is in Redmond, located on the fairgrounds off of parking lot D but there is an office in Jefferson county on highway 26 just off of Dogwood if you prefer to take your plant there.  
From the picture I see no evidence of insect damage. We will need to know growing conditions, fertilization, watering program, variety of tomatoes and any other information that will help us identify what is going on.