Antibiotic Susceptibility of Commensal Bacteria from Human Milk.
Recent studies have focused on foodborne or commensal bacteria as vehicles of antibiotic resistance. However, the antibiotic resistance of milk bacteria from healthy donors is still vague in Taiwan. For this purpose, human milk samples were obtained from randomly recruited 19 healthy women between 3 and 360 days post-partum. Antibiotic susceptibility profile of bacteria from milk samples was determined. About 20 bacterial species were isolated from milk samples including Staphylococcus (6 species), Streptococcus (4 species), Enterococcus (2 species), Lactobacillus (1 species), and bacteria belonging to other genera (7 species). Some opportunistic or potentially pathogenic bacteria including Kluyvera ascorbata, Klebsiella oxytoca, Klebsiella pneumoniae, Acinetobacter baumannii, Actinomyces bovis, and Staphylococcus aureus were also isolated. Intriguingly, Staphylococcus isolates (22 strains) were resistant to 2–8 of 8 antibiotics, while Streptococcus isolates (3 strains) were resistant to 3–7 of 9 antibiotics, and members of the genus Enterococcus (5 strains) were resistant to 3–8 of 9 antibiotics. Notably, Staphylococcus lugdunensis, S. aureus, Streptococcus parasanguinis, Streptococcus pneumonia, and Enterococcus faecalis were resistant to vancomycin, which is considered as the last-resort antibiotic. Therefore, this study shows that most bacterial strains in human milk demonstrate mild to strong antibiotic resistance. Whether commensal bacteria in milk could serve as vehicles of antibiotic resistance should be further investigated.
Department of Nursing, St. Mary's Junior College of Medicine, Nursing and Management, Taiwan, Republic of China. pwchen@smc.edu.tw.
Po-Wen
http://orcid.org/0000-0003-1230-1532
PW
Chen
Department of Veterinary Medicine, National Chung-Hsing University, Taiwan, Republic of China.
Shu-Ying
SY
Tseng
Department of Medicine Laboratory, St. Mary's Hospital Luodong, Taiwan, Republic of China.
Mao-Sheng
MS
Huang
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001419:Bacteria / Q000145:classification / Q000187:drug effects / Q000302:isolation & purification; D024881:Drug Resistance, Bacterial; D064368:Healthy Volunteers; D008826:Microbial Sensitivity Tests; D008895:Milk, Human / Q000382:microbiology; D049590:Postpartum Period; D013624:Taiwan; D006801:Humans
D000900:Anti-Bacterial Agents