title: Prevalence, antibiotic resistance, and extended-spectrum and AmpC β-lactamase productivity of Salmonella isolates from raw meat and seafood samples in Ho Chi Minh City, Vietnam.
abstract: Salmonellosis is a type of foodborne disease caused by Salmonella enterica and is a frequent cause of childhood diarrhea in Vietnam. Of particular concern is the dissemination of multidrug-resistant Salmonella, as extended-spectrum β-lactamase (ESBL)-positive isolates were recently detected in children in Vietnam. In the present study, the prevalence and antibiotic resistance of Salmonella isolates obtained from 409 raw meat and seafood samples collected between October 2012 and March 2015 from slaughterhouses, wholesale fish market, and retail markets in Ho Chi Minh City, Vietnam were examined. A high rate of Salmonella contamination was detected in the pork (69.7%), poultry (65.3%), beef (58.3%), shrimp (49.1%), and farmed freshwater fish samples (36.6%). A total of 53 Salmonella serovars were found, of which S. Rissen, S. Weltevreden, S. London, S. Anatum, S. Typhimurium, and S. Corvallis were the most prevalent. In addition, 4 monophasic S. Typhimurium strains were identified using a PCR method for the detection of a specific IS200 fragment within the fliB-fliA intergenic region. The Salmonella isolates had a high prevalence (62.2%) of resistance to antimicrobial agents, particularly tetracycline (53.3%), ampicillin (43.8%), chloramphenicol (37.5%), and trimethoprim/sulfamethoxazole (31.3%). Isolates with resistance to three or more classes of antimicrobials were found (41.1%). Especially, isolates such as S. monophasic Typhimurium, S. Schwarzengrund, S. Indiana, S. Newport, S. Saintpaul and S. Bovismorbificans exhibited resistance to 6 classes of antimicrobials (3.3%). All 7 S. Indiana strains were resistant to between 4 and 6 classes of antimicrobials, including ciprofloxacin, which is commonly used for the treatment of human Salmonella infections. Two fish isolates were confirmed to be CTX-M-55 ESBL-producing Salmonella serovars Bovismorbificans and Newport, and five CMY-2 AmpC-producing Salmonella isolates of serovars Braenderup (4) and Typhimurium (1) were detected in poultry samples. The findings from this study, which is the first report of ESBL- and AmpC-producing Salmonella isolates from food in Vietnam, indicate that multidrug-resistant Salmonella are widely disseminated not only in meats, but also in seafood, within the food distribution system of Vietnam. The presence of these multidrug-resistant strains is a public health concern and suggests that the use of antimicrobial agents in both humans and animals in Vietnam should be tightly controlled.
authors.affiliation: The Southern Regional Testing Center of Food Safety, Institute of Public Health Ho Chi Minh City, Ministry of Health, 159 Hung Phu St, Ward 8, Dist. 8, Ho Chi Minh City, Viet Nam. Electronic address: anhdao.iph@gmail.com.
authors.forename: Dao Thi Anh
authors.initials: DT
authors.lastname: Nguyen
authors.affiliation: Department of Infectious Disease, Osaka Prefectural Institute of Public Health, Nakamichi, Osaka 537-0025, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Kanki
authors.affiliation: The Southern Regional Testing Center of Food Safety, Institute of Public Health Ho Chi Minh City, Ministry of Health, 159 Hung Phu St, Ward 8, Dist. 8, Ho Chi Minh City, Viet Nam.
authors.forename: Phuc Do
authors.initials: PD
authors.lastname: Nguyen
authors.affiliation: The Southern Regional Testing Center of Food Safety, Institute of Public Health Ho Chi Minh City, Ministry of Health, 159 Hung Phu St, Ward 8, Dist. 8, Ho Chi Minh City, Viet Nam.
authors.forename: Hien Thi
authors.initials: HT
authors.lastname: Le
authors.affiliation: The Southern Regional Testing Center of Food Safety, Institute of Public Health Ho Chi Minh City, Ministry of Health, 159 Hung Phu St, Ward 8, Dist. 8, Ho Chi Minh City, Viet Nam.
authors.forename: Phong Thanh
authors.initials: PT
authors.lastname: Ngo
authors.affiliation: The Southern Regional Testing Center of Food Safety, Institute of Public Health Ho Chi Minh City, Ministry of Health, 159 Hung Phu St, Ward 8, Dist. 8, Ho Chi Minh City, Viet Nam.
authors.forename: Doan Nguyen Minh
authors.initials: DN
authors.lastname: Tran
authors.affiliation: The Southern Regional Testing Center of Food Safety, Institute of Public Health Ho Chi Minh City, Ministry of Health, 159 Hung Phu St, Ward 8, Dist. 8, Ho Chi Minh City, Viet Nam.
authors.forename: Ninh Hoang
authors.initials: NH
authors.lastname: Le
authors.affiliation: The Southern Regional Testing Center of Food Safety, Institute of Public Health Ho Chi Minh City, Ministry of Health, 159 Hung Phu St, Ward 8, Dist. 8, Ho Chi Minh City, Viet Nam.
authors.forename: Chinh Van
authors.initials: CV
authors.lastname: Dang
authors.affiliation: Department of Infectious Disease, Osaka Prefectural Institute of Public Health, Nakamichi, Osaka 537-0025, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Kawai
authors.affiliation: Department of Infectious Disease, Osaka Prefectural Institute of Public Health, Nakamichi, Osaka 537-0025, Japan.
authors.forename: Ryuji
authors.initials: R
authors.lastname: Kawahara
authors.affiliation: Department of Infectious Disease, Osaka Prefectural Institute of Public Health, Nakamichi, Osaka 537-0025, Japan.
authors.forename: Shinya
authors.initials: S
authors.lastname: Yonogi
authors.affiliation: Department of Infectious Disease, Osaka Prefectural Institute of Public Health, Nakamichi, Osaka 537-0025, Japan.
authors.forename: Yuji
authors.initials: Y
authors.lastname: Hirai
authors.affiliation: Department of Infectious Disease, Osaka Prefectural Institute of Public Health, Nakamichi, Osaka 537-0025, Japan.
authors.forename: Michio
authors.initials: M
authors.lastname: Jinnai
authors.affiliation: Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Osaka 598-8531, Japan.
authors.forename: Shinji
authors.initials: S
authors.lastname: Yamasaki
authors.affiliation: Department of Infectious Disease, Osaka Prefectural Institute of Public Health, Nakamichi, Osaka 537-0025, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Kumeda
authors.affiliation: Department of Infectious Disease, Osaka Prefectural Institute of Public Health, Nakamichi, Osaka 537-0025, Japan; Global Collaboration Center, Osaka University, Osaka 565-0871, Japan.
authors.forename: Yoshimasa
authors.initials: Y
authors.lastname: Yamamoto
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D002417:Cattle; D024881:Drug Resistance, Bacterial; D005506:Food Contamination / Q000032:analysis*; D006801:Humans; D016133:Polymerase Chain Reaction; D011200:Poultry; D015995:Prevalence; D000069466:Red Meat / Q000382:microbiology*; D012475:Salmonella / Q000145:classification / Q000187:drug effects / Q000201:enzymology / Q000302:isolation & purification*; D012478:Salmonella Food Poisoning / Q000382:microbiology; D017747:Seafood / Q000382:microbiology*; D013552:Swine; D014744:Vietnam; D001618:beta-Lactamases / Q000235:genetics / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; C048795:AmpC beta-lactamases; D001618:beta-Lactamases
keywords: AmpC; ESBL; Meat; Salmonella; Seafood; Vietnam