Location: Food and Feed Safety ResearchTitle: Advances in vaccines for controlling foodborne Salmonella spp. in poultry
|Kogut, Michael - Mike
|SANTIN, ELIZABETH - Universidade Federal Do Parana
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 1/24/2019
Publication Date: 3/12/2019
Citation: Kogut, M.H., Santin, E. 2019. Advances in vaccines for controlling foodborne Salmonella spp. in poultry. In: Venkitanarayanan K., Thakur S., Ricke S., editors. Food Safety in Poultry Meat Production. Cham, Switzerland: Springer Nature Switzerland. p. 161-189.
Technical Abstract: Salmonellosis is a zoonotic disease caused by the gram-negative enteric bacterium Salmonella. Many serotypes, collectively known as broad-host range serovars, such as S. Typhimurium and S. Enteritidis, are not restricted to particular host species and their epidemiology can therefore be complex. These serotypes do not cause severe symptoms in poultry, but the eggs and meat of infected animals can become a reservoir of infection for the human consumer. In particular, asymptomatic carriers have a major role in Salmonella propagation in poultry and hence in food contamination, since they cannot be easily identified and isolated. The intestinal carrier state of chickens infected with S. enterica is one of the main causes of disease propagation in poultry. Vaccination is the most practical and effective method to control salmonellosis in poultry. This can lead to a decrease in public health risk by reducing the bacterial intestinal colonization and organ invasion and decrease horizontal transmission by reducing fecal shedding and environmental bacterial contamination. However, the ability of non-typhoid Salmonella in broiler chickens to survive, colonize, and persist in the intestinal tract is dependent upon a series of bacterial factors that lead to the asymptomatic infection. It has been clearly shown that vaccination of chickens results in a quantitative reduced level and duration of intestinal colonization, reduced extra-intestinal organ invasion by Salmonella challenge organisms, and reduced egg contamination following vaccination under experimental conditions. However, a challenge infection with a wild-type strain will not result in absolute protection against intestinal colonization. Further, the intestinal microbiome has been shown to regulate local and systemic immunity, yet it has been completely ignored when evaluating the efficacy of vaccines in poultry. Therefore, in this chapter, we will concentrate our discussion on relevant areas of the host-bacteria interactions that must be addressed when developing potential vaccines to reduce and control non-typhoid Salmonella infections in broilers chickens. For example, what effects do the bacterial immune evasion mechanisms have on a vaccine-induced a protective immune response; i.e., does a protective immunity override these evasion mechanisms upon a challenge infection? Do gut microbes impact vaccine efficacy and, if so, to what extent? For future vaccine development, we need to find answers to these questions.