Vaccination against Trichinella spiralis: Potential, Limitations and Future Directions

Abstract

Trichinellosis is a food-borne parasitic disease caused by round worms of the genus Trichinella. The majority of human outbreaks are attributed to consumption of raw or undercooked pork meat contaminated with T. spiralis muscle larvae. A blockingtransmission vaccine against trichinellosis will allow preventing swine infection and will contribute to disease control. In this chapter, different vaccine candidates so far developed against T. spiralis, including first-, second-, and third-generation vaccines, are discussed. Most vaccine candidates are based on a unique antigen mainly from the muscle larva stage, inducing with some exceptions, partial protection although a mix Th1/Th2 immune response is elicited. Therefore, the need for identification of new antigens from different parasite stages focusing on infective intestinal larvae, adult, and newborn larvae stages as well as the evaluation of their protective capacity in pigs is presented. The design of multi-epitope vaccines and the use of adjuvants or immunomodulatory molecules capable to polarize the immune response to a Th2-type-protective response are discussed as imperative elements of modern vaccines. Plant-based vaccines and probiotics as excellent tools for vaccine development against T. spiralis are also presented as an attractive platform for veterinary vaccines.