Zoonotic Infections: A Case Study

Treatment of zoonotic infections in both animals and humans is not only a humanitarian action, but also shortens the length of sickness and, hence, the period of communicability, thereby providing a valuable measure in countering and controlling of the spread of zoonotic diseases (Mantovani, 1992; Webber, 2005). However, the diminishing utility of current antibiotics in the face of rising bacterial resistance and the stagnant development of new antibiotics constitute the main obstacles for achieving an effective treatment which further underscores the urgent need for the development of alternative therapeutic options (Mohamed et al., 2014). This scourge is further compounded by intracellular zoonotic pathogens, such as Mycobacterium, Salmonella, Listeria, and Brucella that reside and thrive inside mammalian cells (Seleem et al., 2009a, 2009b; Nepal et al., 2015). Treatment of infections caused by these intracellular pathogens is very challenging because most antibiotics are unable to access intracellular replicative niches and achieve the optimum therapeutic concentrations within the infected cells (Seleem et al., 2009a, 2009b). For instance, the mortality rate in human listeriosis remains high (20-30%) even

One potential novel alternative therapeutic approach to treat infections caused by intracellular zoonotic pathogens that has shown promise in recent years is silencing essential genes with a peptide nucleic acid (PNA) (Alajlouni and Seleem, 2013; Rajasekaran et al., 2013). In addition to the hybridization affinity to their target DNA and RNA sequence, and specificity of PNA molecules to silence genes, these molecules are characterized by chemical and enzymatic stability conferred by their pseudopeptide backbone as well as low toxicity to host tissues (Good and Nielsen,