Does anyone know if there is a connection between infection and chronic fatigue syndrome?

Many cases, yes. With certain infections that forces your body to activates its immune defenses( for example, infectious mononucleosis) requires a lot of energy over an extended period. During this time, the immune system is also producing factors called cytokines, some of which can also cause fatigue. While a number of cases are related to infections, many others are not connected to cfs and await discovery.