Chronic norovirus infection in a patient with a past history of Burkitt lymphoma.

The noroviruses are a leading cause of gastroenteritis worldwide. Although the illness is normally mild and self-limiting, there is a growing literature documenting the chronic excretion of norovirus in the immunocompromised. The aim of the current study was to examine the molecular features of chronic norovirus excretion in an immunocompromised patient with a past history of Burkitt lymphoma. During the 241 day course of the study from December 2013 to August 2014, seven faecal specimens were collected from the patient, tested for norovirus by RT-PCR and further analysed in the open reading frame (ORF) 1 and ORF 2 regions. All seven specimens were positive for norovirus by RT-PCR. Molecular sequencing in the polymerase (ORF 1) and capsid (ORF 2) regions indicated that the norovirus could be classified as GII.4 (2006b)/GII.4 (unknown). No significant mutation was found in the ORF 1 or ORF 2 regions analysed over the period of the study. The current report appears to be the first to document chronic norovirus excretion in a patient with a past history of Burkitt lymphoma. It is also the first to indicate long term norovirus excretion in a given individual need not involve major genetic change in key regions of the genome.