Abstract

According to the 2019 census, 110,000 death occurs globally out of 9.2 million typhoid fever cases with the most inappropriate share being accounted by the South Asian countries. Antibiotics in the treatment of typhoid have shown promising solutions but can hinder the microbial genome and can give rise to the emergence of MDR-resistant species. Bacteriophage treatment has been observed to be a more effective solution than antibiotics for overcoming such problems. It has a number of benefits over antibiotics, such as the ability to treat MDR species and prevent their development. The current study focuses on the isolation and characterization of phage specific against fluoroquinolone-resistant Salmonella spp  and its effectiveness under extreme circumstances and in food sources.  The isolated bacteriophage from the sewage sample was shown to be effective against 8 strains of fluoroquinolone-resistant Salmonella spp. According to a time-kill analysis investigation, bacteriophages can effectively kill hosts at 0.01 MOI by the eighth hour with a 3-minute adsorption time, a 10-minute latency period, and a burst size of 124,333pfu/ml. The stability studies showed that phage was moderate efficiency at extreme pH and highly efficient at extreme temperatures. Apart from these, the isolated phage was highly effective against 6/8 host strains and moderately effective against the other 2 hosts. Salmonella spp. are diseases that may be spread via food; hence the effectiveness of bacteriophages was also primarily examined in food sources like eggs. It was observed that phages are efficient in egg medium in the presence of Salmonella spp. at high concentrations. Considering the experimental finding, it can be established that the isolated phage can be used as an alternative to antibiotics to treat fluoroquinolone-resistant Salmonella spp. infection

Keywords: Salmonella spp., bacteriophage, fluroquinolone, antibiotics.