Molecular techniques for the detection of bacterial zoonotic pathogens in fish and humans Akram Farzadnia 1 & Mohsen Naeemipour 1 Received: 9 January 2019 /Accepted: 21 August 2019/ # Springer Nature Switzerland AG 2019 Abstract Various diseases could be transmitted from aquatic species, especially fish, to humans, which is considered to be a major human health concern across the world. In recent decades, molecular techniques have been applied to examine and identify various bacterial species in fish farms. Molecular techniques are rapid, accurate, sensitive, cost-effective, and have the ability to identify specific pathogens without the need for conventional methods. Furthermore, molecular techniques are particularly useful for the detection of multiple species or in case of low template. This review study aimed to describe various molecular methods, including multiplex-polymerase chain reaction, high-resolution melting real-time, restriction fragment length polymorphism, random amplification of polymorphic DNA, nucleic acid sequence- based amplification, rolling circle amplification, fluorescence in-situ hybridization, microarray, and matrix-assisted laser desorption/ionization. In addition, we evaluated the biosensors used for the detection of zoonotic bacteria, such as Vibrio vulnificus, Vibrio cholerae, Listeria monocytogenes, Streptococcus iniae, Lactococcus garvieae, Aeromonas hydrophila, Edwardsiella tarda, Mycobacterium spp., Photobacterium damselae subsp. Damselae, and Pseudomonas fluorescens, which are transmitted from fish to humans. These bacteria are of great importance in the aquaculture industry and in terms of human health. Keywords Zoonotic Bacteria . Molecular techniques . Aquatic species Molecular techniques for the identification of zoonotic Bacteria Zoonoses or zoonotic diseases refer to the infections that are transmitted from various animals to humans either directly or by a carrier. Approximately 1500 pathogens have been identified in this regard (Cantas and Suer 2014), most of which could be transmitted to humans through fish and shellfish. Fish is an important source of protein for millions of individuals across the world. Approximately 50% of fish is provided by the aquaculture industry for human Aquaculture International https://doi.org/10.1007/s10499-019-00462-7 * Mohsen Naeemipour m.naeemipour@gmail.com 1 Cellular and Molecular Research Center, Sabzevar University of Medical Sciences, Sabzevar, Iran