F. tularensis causes zoonotic disease tularemia was discovered in 1911 during plaque-like disease in California. F. tularensis infect humans, fish, birds, and invertebrates (Mörner, 1992). F. tularensis contain 3 subspecies, type A (tularensis), type B (holarctica), and mediasiatica different from each other in terms of a life cycle, reservoirs, and geographic distribution. In humans, both type A and B cause tularemia. The disease is transmitted by eating contaminated food and drinking water from rivers, lakes, and ponds (Akalın, Helvacı, & Gedikoğlu, 2009; Hennebique, Boisset, & Maurin, 2019). Tularemia caused by F. tularensis highly reported in Iran such as Azerbaijan, Kazakhstan, Armenia, and Turkmenistan (Jung et al., 2019) in U.S and Turkey (Gurcan et al., 2008). Due to its high mortality and infectious nature, F. tularensis were highly studied in the respiratory tract. F. tularensis pathogen infect via gastrointestinal tract through ingestion and by the skin through bites of infected arthropods, insect, or handling infected animals (Petersen, Mead, & Schriefer, 2009). These infection result in other 2 clinically form of tularemia such as oropharyngeal and ulceroglandular. These disease are further effect the stomach ulcers, fever, and swollen and skin ulcers (Nicol, Williamson, Place, & Kirimanjeswara, 2021).
F. tularensis showed resistance to different antibiotics such as Penicillin, Polymyxin B, Erythromycin, and Azithromycin. This type of resistance is mainly dependent on different strains and species, and also depends on their chromosomal genes expression. F. tularensis was found to be showed resistance to monobactams by the same beta-lactamase genes (Caspar & Maurin, 2017). F. tularensis displayed its resistance to carbapenem antibodies which are proved by the F. tularensis blaA2 gene (Bina, Wang, Miller, & Bina, 2006). However, the development of multidrug resistance may reduce multidrug efficacy against F. tularensis, therefore different approaches like immunization and vaccination are used to activate an immune response against disease (Khatoon, Pandey, & Prajapati, 2017).
Two evidence are used to support F. tularensis vaccine development. The first one is immunospecific protection against reinfection (Burke, 1977; Tärnvik, 1989) second is immunization along with a live vaccine strain that showed efficacy for wild-type humans. F. tularensis is a dangerous intracellular pathogen that led to finalized that cell-mediated immunity is important for protection. This assumption was born out in different research studies. Antibodies' roles are also established, which suggests a development of successful vaccine is important for both cell-mediated response and humoral. The demand for an effective F. tularensis vaccine is clear; in a short period, the successful vaccine will be safe for protective immunity. Therefore, in the present study immunoinformatics approaches are used to design an effective vaccine against F. tularensis.