Viable but non-culturable forms of food and waterborne bacteria: Quo Vadis?

There is increasing evidence for a viable but non-culturable (VBNC) state in microbes, particularly in the stressing environment presented by modern foods with their varied pre-treatment and packaging strategies. This is a cause for concern because of evidence that microbial pathogens in such a state may retain their capacity to cause infections after ingestion by the consumer despite their inability to grow under the conditions employed in procedures for determining their presence in foods. Heavily stressed pathogenic species of bacteria in a VBNC or not immediately culturable state are potentially dangerous public health problems, particularly as stressed cells may be more virulent than well-fed bacteria. In this viewpoint article, I wish to focus on possible procedures for detecting such organisms and assessing their physiological state.