Characteristics of antibiotic resistance of some salmonella enteritidis isolates in the Philippines

• Main Author: Fandialan, Monina M.
• Format: text
• Language: English
• Published: Animo Repository 1994
• Subjects: Microbial sensitivity tests; Antibiotics > Testing; Microorganisms—Effect of temperature on; Drug resistance in microorganisms; Microbiology
• Online Access: https://animorepository.dlsu.edu.ph/etd_doctoral/1189
• Institution: De La Salle University

Fourteen out of 86 isolates (16 percent) of Salmonella enteritidis collected from different surveillance posts in the Philippines by the Bureau of Research and Laboratories, Department of Health, Manila showed resistance to either one or more of the following antibiotics tested against them: ampicillin, chloramphenicol, co-trimoxazole, streptomycin, tetracycline and nalidixic acid. The percentages of the isolates resistant to the different antibiotics were as follows: co-trimoxazole (93 percent), ampicillin (92 percent), choramphenicol (85 percent), tetracycline (85 percent), streptomycin (78 percent) and nalidixic acid (13 percent). Thirteen of the 14 isolates possessed resistance to two or more antibiotics. The incidence of resistance were highest in S. ser typhimurium at 73 percent and S. ser senftenberq at 67 percent. The most frequent antibiotic resistance pattern found among the isolates was ampicillin - choramphenicol - streptomycin - co-trimoxazole - tetracycline which occurred in 50 percent of the resistant isolates. All the isolates possessed transferable resistance by in-vitro conjugation with Escherichia coli SF 800 with conjugation frequency ranging from 1.63 x 10 to negative 4 to 8.55 x 10 to negative 2. The incompatibility test of the plasmids of two isolates tested suggested that their plasmids belonged to the same incompatibility group. Antibiotic resistance was either lost or gained in some isolates during three months of storage at room temperature.