The viable but non-culturable (VBNC) state of Campylobacter jejuni lacks propagation ability in the mouse intestinal tract

Campylobacter jejuni is a foodborne pathogen found worldwide. It can exist in a viable but non-culturable (VBNC) state under environmental stresses and cannot be cultured in this state. Whether C. jejuni retains its pathogenicity or causes food poisoning by resuscitation from the VBNC state remains unclear. This research aimed to evaluate whether C. jejuni in the VBNC state should be accounted for in prevention strategies against Campylobacter food poisoning. The VBNC state of C. jejuni strain NCTC11168 was induced at 4{degrees}C under aerobic conditions. A mouse model (C57BL/6, 3-week-old male) was prepared by administering a defined zinc-deficient diet and antibiotics in drinking water. Each mouse was administered C. jejuni with approximately 107 colony-forming units of culturable cells, cells in the VBNC state, or Muller-Hinton broth as a control. In culturable cell-infected mice, an increase in the number of C. jejuni in stool was observed using colony counting and quantitative polymerase chain reaction. No culturable cells were present in VBNC cell-infected mice. Clinical signs, weight loss, or significant increase in lipocalin-2 and myeloperoxidase levels, as inflammatory biomarkers, were not observed in culturable cell- or VBNC cell-infected mice. Thus, culturable cells colonized the mouse intestinal tract, whereas cells in the VBNC state could not. In the VBNC state, C. jejuni may not pose a risk of food poisoning. Further investigations on the colonization and pathogenicity of C. jejuni in the VBNC state in the human intestinal tract are required.