A 68-year-old man, immunocompromised due to non-Hodgkin lymphoma and chemotherapy, was admitted for a community-acquired norovirus infection. He developed chronic intermittent diarrhoea and cachexia. A video-capsule examination showed severe mucosal atrophy in the jejunum. The patient died eight months after the initial norovirus infection. Eight of the nine stool examinations were positive for the norovirus during this entire period. Excretion of norovirus is known to persist after the symptoms have been resolved. However, there is only one previously reported case of excretion over such a long period. Recognising a chronic norovirus infection in immunocompromised patients is vital as then complications such as mucosal atrophy with malabsorption and cachexia can be diagnosed and supportive therapy can be started. Furthermore, recognising a chronic norovirus infection is essential for preventing norovirus outbreaks. Infected patients should always be isolated, regardless of their symptoms and faecal viral load.