What does a persistent sore throat mean? what could be the likely causes for a sore throat lasting more than two weeks?

Sore throat: A sore throat has many potential causes -- infectious (viral or bacterial), post nasal drip/allergies, gastroesophageal or laryngopharyngeal reflux, ulceration, or in rare cases, cancer. Chronic sore throat is best evaluated by your primary care doctor in conjunction with an ear, nose, and throat specialist.

Many possibilities: Without more detailed information about the location, the type of soreness, its relationship to other activities, and ancillary symptoms it is impossible to tell what this is due to. Any illness lasting more than two weeks, however, deserves a thorough evaluation. See your primary care physician and if needed they can refer you to an ear nose and throat doctor.