Rickettsial Diseases and Vaccines: Is There an Opportunity for Plant‐Made Vaccine Technology?

Rickettsiosis is a zoonotic disease caused by obligate intracellular bacteria of the family Rickettsiae, transmitted by arthropods. No commercial vaccine exists, despite the efficacy of experimental prototypes based on whole cells, DNAs, nanosystems, and recombinant antigens. Plants have been used as a platform for producing and delivering recombinant antigens, allowing the commercial vaccines for COVID‐19 and Influenza. This technology can be used for recombinant Rickettsia vaccines for the target host, potentially for vector arthropods. These aspects are reviewed in this work, considering a brief immunobiology of Rickettsiae, experimental vaccines against Rickettsiosis, step‐by‐step genetic engineering in plants for recombinant antigen production and immunological assessment, representative successful examples of plant‐made vaccines, and the analysis of the potential of plant‐made vaccines to control arthropod‐transmitted Rickettsiae. Perspectives in this field are offered, highlighting hurdles and opportunities.