Lymphocytes are a type of white blood cell that we all have in our bodies. They, along with a number of other different types of white blood cells are responsible fighting infections. Infections are caused by micro-organisms, commonly viruses or bacteria, that breach our bodies defences and can make us unwell. Lymphocytes are a type of white blood cell that are involved in fighting viral infections. This means that if your lymphocyte count is high then it probably means you have a viral infection of some sort that your body is fighting. There are rarer causes of a raised lymphocyte count such as chronic lymphocytic leukaemia, most common in the elderly. If you are worried do consult your GP further advice.