Lack of colonization of 1 day old chicks by viable, non-culturable Campylobacter jejuni

G.J. MEDEMA, F.M. SCHETS, A.W. VAN DE GIESSEN AND A.H. HAVELAAR. 1992. Seven strains of Campylobacter jejuni , isolated from various sources human ( n = 2), chicken ( n = 3), water ( n = 2)], were studied under starvation conditions in filter-sterilized and pasteurized surface water by acridine orange direct count (AODC), viable count (DVC) and culture methods. Plate counts showed a rapid decline (2 log-units/day) for all strains under these conditions. Only one of the seven strains (14%) showed a (prolonged) viable, non-culturable 'state'. The ability of these viable, non-culturable cells to colonize the intestine was tested on day-old chicks. The infectious oral dose of freshly cultured cells of this model was 26–260 cfu; 1.8×10⁵ viable, non-culturable C. jejuni were introduced to day-old chicks orally. Campylobacter jejuni was not isolated from the caeca of the chicks after incubation for 7 d. Also, passage through the allantoic fluid of embryonated eggs did not recover viable, nonculturable C. jejuni. These findings cast serious doubts on the significance of the viable, non-culturable 'state' in environmental transmission of C. jejuni.