RESUMEN
Acute hepatopancreatic necrosis disease (AHPND) caused by Vibrio parahaemolyticus has been one of the most problematic diseases in marine shrimp aquaculture throughout Southeast Asia and Latin America. To evaluate the effectiveness of a bacteriophage (phage) treatment for AHPND, a series of bioassays were carried out in a marine shrimp (Penaeus vannamei) model using an AHPND-V. parahaemolyticus strain that is highly pathogenic to shrimp. We monitored the mortality and histopathological changes during phage treatment. Shrimps treated with phage prophylaxis and phage therapy displayed significant protection from AHPND and survived a lethal bacterial challenge.
RESUMEN
Salmonella enterica serovar Enteritidis is one of the most common causes of Salmonellosis worldwide. Utilization of bacteriophages as prophylactic agents is a practical solution to prevent Salmonellosis in ready-to-eat products. Shelf stability is one of the desirable properties for prophylactic bacteriophages. Here, we describe the phenotype, genome, and phylogeny of fSE1C and fSE4S Salmonella bacteriophages. fSE1C and fSE4S were previously isolated from pickle sauce and ground beef respectively and selected for their significant shelf stability. fSE1C and fSE4S showed a broad S. enterica serovar range, infecting several Salmonella serovars. The viral particles showed an icosahedral head structure and flexible tail, a typical morphology of the Siphoviridae family. fSE1C and fSE4C genomes consists of dsDNA of 41,720 bp and 41,768 bp with 49.73% and 49.78% G + C, respectively. Comparative genomic analysis reveals a mosaic relationship between S. enterica serovar Enteritidis phages isolated from Valparaiso, Chile.
RESUMEN
Traveler's diarrhea (TD) is caused by Escherichia coli in 30% of cases. We have developed a phage cocktail for prophylaxis of TD caused by E.coli, Shigella flexneri, Shigella sonnei, Salmonella enterica, Listeria monocytogenes or Staphylococcus aureus, and investigated its effectiveness against infection caused by the non-pathogenic Lac (-) strain of E.coli K12 C600 in animal and human trials. On the 6th day of both animal and human trials E. coli K12 C600 strain was detected in titer of 104 CFU/g of mice feces and 106 CFU/g of human feces in the control (untreated) groups, while it was not detected in the samples of either of the study (phage-treated) groups. These results have great significance because the original coliphages included in the cocktail have a broad host-range including ETEC, EAEC and EHEC strains which cause severe cases of TD.