Isolation, Characterization, and Efficacy of Three Lytic Phages Infecting Multidrug-Resistant Salmonella Serovars from Poultry Farms in Egypt.

Multidrug-resistant (MDR) Salmonella serovars are considered a significant threat to veterinary and public health. Developing new antimicrobial compounds that can treat the infection caused by these notorious pathogens is a big challenge. Bacteriophages can be adsorbed on and inhibit the growth of bacteria, providing optimal and promising alternatives to chemical antimicrobial compounds against foodborne pathogens due to their abundance in nature and high host specificity. The objective of the current study was to isolate and characterize new phages from poultry farms and sewage and to evaluate their efficacy against S. Enteritidis isolates. The study reports three lytic phages designated as ϕSET1, ϕSET2, and ϕSET3 isolated from poultry carcasses and sewage samples in Qalubiya governorate Egypt. The effectiveness of phages was evaluated against multidrug-resistant S. Enteritidis strains. Electron microscopy showed that these phages belong to the Siphoviridae family. Phages were tested against 13 bacterial strains to determine their host range. They could infect four S. Enteritidis and one S. Typhimurium; however, they did not infect other tested bacterial species, indicating their narrow infectivity. The bacteriophage's single-step growth curves revealed a latent period of 20 min for ϕSET1 and 30 min for ϕSET2 and ϕSET3. The isolated Salmonella phages prevented the growth of S. Enteritidis for up to 18 hrs. The findings revealed that Salmonella phages could be used as alternative natural antibacterial compounds to combat infection with MDR S. Enteritidis in the poultry industry and represent a step forward to using large panels of phages for eliminating Salmonella from the food chain.

An outbreak of peste des petits ruminants in migratory flocks of sheep and goats in Egypt in 2006.

An outbreak of peste des petits ruminants (PPR) was recorded in Kalubia province, Egypt in 2006, affecting a large population of migratory goats and sheep over a huge geographical area. Epidemiological, clinical and laboratory investigations were performed. Diseased animals showed pyrexia, erosive stomatitis, enteritis and bronchopneumonia. Clinical manifestations were more severe in goats. The overall morbidity, cumulative mortality and case fatality rates were 26.1%, 10.5% and 40.2%, respectively, and were significantly higher in young animals. Post-mortem examination showed emaciation, congested mucous membranes, lymphadenopathy, hepatosplenomegaly, haemorrhagic necrosis of the abomasal and intestinal mucosa, pleurisy and lung consolidation. Forty oculonasal swabs and 243 serum samples from diseased animals were tested for PPR antigen and antibodies using immunocapture and competitive enzyme-linked immunosorbent assays (ELISA), respectively. PPR antigen was detected in 30/40 (75%) of the swabs. PPR virus was identified in inoculated Vero cells using immunocapture ELISA and fluorescent antibody technique (FAT); 33/40 (82.5%) and 36/40 (90%) samples were positive, respectively. Of 243 sera, 154 (63.4%) contained PPR antibodies. Circulation of PPR among the migratory sheep and goat flocks was demonstrated. Strict serosurveillance and monitoring of PPR with vaccination of migratory flocks at borders is required for effective control of the disease.