1.Effectiveness of cephalosporins Microbiology in hydrolysis and inhibition of Staphylococcus aureus and Escherichia coli biofilms
Jawaria ASLAM ; Hafiz MUHAMMAD ALI ; Shujaat HUSSAIN ; Muhammad Zishan AHMAD ; Abu Baker SIDDIQUE ; Muhammad SHAHID ; Mirza Imran SHAHZAD ; Hina FATIMA ; Sarah TARIQ ; Fatima SADIQ ; Maria ASLAM ; Umar FAROOQ ; Saadiya ZIA ; Rawa Saad ALJALUOD ; Khaloud Mohammed ALARJANI
Journal of Veterinary Science 2024;25(3):e47-
Objective:
The study examined the efficacy of various generations of cephalosporins against biofilms developed by pathogenic S. aureus and E. coli.
Methods:
The development of biofilms by both bacteria was assessed using petri-plate and microplate methods. Biofilm hydrolysis and inhibition were tested using first to fourth generations of cephalosporins, and the effects were analyzed by crystal violet staining and phase contrast microscopy.
Results:
Both bacterial strains exhibited well-developed biofilms in petri-plate and microplate assays. Cefradine (first generation) showed 76.78% hydrolysis of S. aureus biofilm, while significant hydrolysis (59.86%) of E. coli biofilm was observed by cefipime (fourth generation). Similarly, cefuroxime, cefadroxil, cefepime, and cefradine caused 78.8%, 71.63%, 70.63%, and 70.51% inhibition of the S. aureus biofilms, respectively. In the case of E. coli, maximum biofilm inhibition (66.47%) was again shown by cefepime. All generations of cephalosporins were more effective against S. aureus than E. coli, which was confirmed by phase contrast microscopy.
Conclusions
and Relevance: Cephalosporins exhibit dual capabilities of hydrolyzing and inhibiting S. aureus and E. coli biofilms. First-generation cephalosporins exhibited the highest inhibitory activity against S. aureus, while the third and fourth generations significantly inhibited E. coli biofilms. This study highlights the importance of tailored antibiotic strategies based on the biofilm characteristics of specific bacterial strains.
2.Emergence of vaccine-derived poliovirus type 2 after using monovalent type 2 oral poliovirus vaccine in an outbreak response, Philippines
SweetC B Alipon ; Yoshihiro Takashima ; Tigran Avagyan ; Varja Grabovac ; Syeda Kanwal Aslam ; Benjamin Bayutas ; Josephine Logronio ; Xiaojun Wang ; Achyut Shrestha ; Sukadeo Neupane ; Maria Concepcion Roces ; Lea Necitas Apostol ; Nemia Sucaldito
Western Pacific Surveillance and Response 2022;13(2):01-07
Objective:
In response to an outbreak of circulating vaccine-derived poliovirus (cVDPV) type 2 in the Philippines in 2019–2020, several rounds of supplementary immunization activities using the monovalent type 2 oral poliovirus vaccine (OPV) were conducted for the first time in the Western Pacific Region. After use of the monovalent vaccine, the emergence of vaccine-derived poliovirus unrelated to the outbreak virus was detected in healthy children and environmental samples. This report describes the detection of this poliovirus in the Philippines after use of the monovalent type 2 OPV for outbreak response.
Methods:
We describe the emergence of vaccine-derived poliovirus unrelated to the outbreak detected after supplementary immunization activities using the monovalent type 2 OPV. This analysis included virus characterization, phylogenetic analyses and epidemiological investigations.
Results:
Three environmental samples and samples from six healthy children tested positive for the emergent vaccine-derived poliovirus. All isolates differed from the Sabin type 2 reference strain by 6–13 nucleotide changes, and all were detected in the National Capital Region and Region 4, which had conducted supplementary immunization activities.
Discussion
Since the 2016 removal of type 2 strains from the OPV, vaccine-derived poliovirus outbreaks have occurred in communities that are immunologically naive to poliovirus type 2 and in areas with recent use of monovalent OPV. To prevent the emergence and further spread of cVDPV type 2, several interventions could be implemented including optimizing outbreak responses by using the monovalent type 2 OPV, accelerating the availability of the novel type 2 OPV, strengthening routine immunization using inactivated polio vaccine and eventually replacing OPV with inactivated poliovirus vaccine for routine immunization.