Abstract: To investigate the pathogenicity of viable but non-cultivable state (VBNC) Vibrio parahaemolyticus (Vp) from salmon consumed raw, the isolated strain VBNC-VpRS1 and the virulent strain Vp17802 were separately orally administered to C57BL/6J mice. The behavior of the mice was observed for the following 72 h, and the disease activity index (DAI) score, Vp load, intestinal damage, tight junction (TJ) protein expression and cytokine levels were measured. It was found that symptoms of infection with VBNC-VpRS1 appeared six hours later than those of infection with Vp17802. Compared with the control group, infection with VBNC-VpRS1 and Vp17802 significantly increased the DAI score, colonic Vp load and the levels of proinflammatory cytokines in mice (P < 0.01 and P < 0.001), and significantly decreased the colon length, anti-inflammatory factor levels and TJ protein expression (P < 0.01, P < 0.001 and P < 0.05). The infected mice showed severe intestinal mucosal tissue defects with hemorrhagic effusion and neutrophil infiltration. Moreover, the colonic Vp load and the degree of pathologic damage in the mice infected with VBNC-VpRS1 were higher than (P < 0.05) those in the mice infected with Vp17802, whereas VBNC-VpRS1 was less effective than Vp17802 in inhibiting the intestinal barrier function and promoting inflammatory responses (P < 0.05). VBNC-VpRS1 can be resuscitated in vivo and has strong colonic adhesion and invasion abilities. As VBNC Vp seriously threatens human health, seafood products consumed raw should be included in the monitoring of Vp.

Key words: salmon consumed raw; viable but non-culturable; Vibrio parahaemolyticus; pathogenicity