Noroviruses (NoVs) are a leading cause of epidemic gastroenteritis in both children and adults worldwide (Glass et al., 2009, J Clin Microbiol 31:2185-91). Outbreaks commonly occur in settings such as hospitals, nursing homes, cruise ships, university dormitories, and military barracks. Although NoV illnesses are generally self-limiting, increased morbidity and mortality have been reported among vulnerable populations such as infants, the elderly, and immunocompromised individuals (Norovirus activity—United States, 2006-2007, MMWR Morb Mortal Wkly Rep 56:842-6; Byce et al., 2005, Lancet 365:1147-52; Green et al., 1993; J Clin Microbiol 31:2185-9; Sakai et al., 2001, Japan. Pediatr Infect Dis J 20:849-53; Zintz et al., 2005, Japan. Pediatr Infect Dis J 20:849-53). It is estimated that NoV infection may account for up to 200,000 deaths per year in infants and young children of developing countries (Patel et al., 2008, Emerg Infect Dis 14:1224-31).
Currently, there are no vaccines or specific antiviral therapies available for the treatment of NoV infections, largely due to the unavailability of permissive cell-culture systems and animal disease models. Most information regarding host immunity to NoV infection has originated from human challenge studies and epidemiological investigations (Atmar et al., 2008, Emerg Infect Dis 14:1553-7; Dolin et al., 1972, Proc Soc Exp Biol Med 140:578-83; Dolin et al., 1971, J Infect Dis 123:307-12; Graham et al., 1994, J Infect Dis 170:34-43; Parrino et al., 1977, N Engl J Med 297:86-9; Wyatt et al., 1974, J Infect Dis 129:709-14). As a result, the immune correlates of protection are poorly understood. Success in expression of recombinant virus-like particles (rVLPs) that mimic the antigenic structure of authentic virions (Prasad et al., 1999, Science 286:287-90; Prasad et al., 1994, J Virol 68:5117-25) and identification of histo-blood group antigens (HBGA) as cellular binding ligands for NoV infection (Harrington, 2002, J Virol 76:12335-43; Hutson et al., 2002, J Infect Dis 185:1335-7; Lindesmith et al., 2003, Nat Med 9:548-53; Marionneau et al., 2002, Gastroenterology 122:1967-77) have facilitated efforts toward the development of prevention and treatment strategies (Atmar et al., 2011, N Engl J Med 365:2178-87; Chang et al., 2007, J Virol 81:12111-8; Feng and Jiang, 2007, Antimicrob Agents Chemother 51:324-31; Herbst-Kralovetz et al., 2010, Expert Rev Vaccines 9:299-307).
A need remains for agents that can be used to treat and/or diagnose a NoV infection, such as a Norwalk virus infection.