The viable but nonculturable (VBNC) state in pathogenic bacteria refers to a condition where cells remain metabolically active but cannot be cultured on standard media. This state is a survival strategy in response to environmental stresses, allowing bacteria to persist in the environment and potentially reinitiate infections upon resuscitation. VBNC cells have been observed in a wide range of pathogens, including human and animal pathogens, and are associated with persistent infections and recurrent disease. Factors inducing the VBNC state include temperature shifts, nutrient starvation, osmotic stress, and exposure to chemicals or light. VBNC cells exhibit reduced metabolic activity, retain virulence, and can resist antibiotics. They can be resuscitated through various means, including removal of inducing stresses, extracellular resuscitation-promoting proteins, quorum-sensing systems, and interactions with host cells. The VBNC state is characterized by changes in cell wall structure, reduced gene expression, and the presence of specific genes involved in stress response and virulence. The catalase enzyme plays a key role in the VBNC response, particularly in bacteria like Vibrio vulnificus. VBNC cells can remain viable for extended periods and are capable of resuscitation, often leading to renewed pathogenicity. The VBNC state is a significant factor in the survival and persistence of pathogens in the environment, with implications for public health, particularly in foodborne and waterborne diseases. Understanding the VBNC state is crucial for developing strategies to control and prevent infections caused by these resilient bacteria.The viable but nonculturable (VBNC) state in pathogenic bacteria refers to a condition where cells remain metabolically active but cannot be cultured on standard media. This state is a survival strategy in response to environmental stresses, allowing bacteria to persist in the environment and potentially reinitiate infections upon resuscitation. VBNC cells have been observed in a wide range of pathogens, including human and animal pathogens, and are associated with persistent infections and recurrent disease. Factors inducing the VBNC state include temperature shifts, nutrient starvation, osmotic stress, and exposure to chemicals or light. VBNC cells exhibit reduced metabolic activity, retain virulence, and can resist antibiotics. They can be resuscitated through various means, including removal of inducing stresses, extracellular resuscitation-promoting proteins, quorum-sensing systems, and interactions with host cells. The VBNC state is characterized by changes in cell wall structure, reduced gene expression, and the presence of specific genes involved in stress response and virulence. The catalase enzyme plays a key role in the VBNC response, particularly in bacteria like Vibrio vulnificus. VBNC cells can remain viable for extended periods and are capable of resuscitation, often leading to renewed pathogenicity. The VBNC state is a significant factor in the survival and persistence of pathogens in the environment, with implications for public health, particularly in foodborne and waterborne diseases. Understanding the VBNC state is crucial for developing strategies to control and prevent infections caused by these resilient bacteria.