Chronic shedders as reservoir for nosocomial transmission of norovirus. J Clin Microbiol, 2010 ; 48(11): 4303-5. te l-0 4, v er sio n - 8 O ct T

Norovirus (NoV) infection in immunocompromised patients may lead to prolonged norovirus shedding. Here, we demonstrate the involvement of three chronic shedders in hospital outbreaks. Combined epidemio-logical and molecular evidence suggests that in one case, NoV transmission occurred at least 17 days after the first diagnosis. Norovirus (NoV) is a leading cause of acute gastroenteritis affecting people of all age groups (1, 3). Outbreaks with NoV occur often and worldwide (7). In the Netherlands, large num-bers of outbreaks are reported each winter, particularly from health care institutions (6). In a systematic evaluation of newly diagnosed patients with norovirus in a large tertiary care hos-pital, we found that nosocomial norovirus transmission is com-mon and may lead to chronic infection, disease, and shedding in at least 6 % of patients (1). The case histories of the chronic patients showed various underlying illnesses resulting in im-paired immunity, followed by prolonged NoV shedding, i