Jpn. J. Infect. Dis., 53, 15‑16, 2000

Short Connunication

Salmonella Typhimurium DT104 from Livestock in Japan
Toshiya Sameshima*, Masato Akiba, Hidemasa Izumlyal, Jun TeraJlmal,Kazumiti Tamural , HaruO Watanabeland Muneo Nakazawa
LaboratoTy OfZoonoses, Feed Research Division, National Institute ofAnimal Health,Kannondai 3‑1‑1, Tsukuba, Ibaraki 305‑0856 andJDepartment ofBacteriology, National Institute ofInfectious Diseases,

Toyama I‑23‑1, Shinjuku‑ku, ZTob,0, Japan(Received November 1 1, 1999. Accepted January 14, 2000)

StJMMARY: ‑We examinedthe distribution of multidrug‑resistant Salmonella enterica serotype Typhimurium
definitive phagetype 104 (DTIO4)among Japanese livestockfrom1973 to 1998. The 144 S･ Typhimurium field
isolates were testedforヲuscePtibilitytoampicillin, chloramphenicol, streptomycin, sulfamethoxamle, tetracycline,kanamycin, trimethoprlm, nalidixic acid,and norfloxacin. Thirty‑six of 68 strains which exhibited resistance tofive or moreantimicrobials (ACSSuT+) were identifled as DT1 04. Results of plasmid profiling showed that all

DTI 04 strains retaina 90‑kb virulence plasmid, while 20 of 36 strains possessed afew additional small plasmids
rangingfrom 2 to 4 kb･ These results showed that DTIO4 strains have existedinJapanese livestock since 1990,

andthat this phagetype may beanimportant pathogen for cattleinJapan.

The multidrug‑resistant Salmonella enterica serotype

pro filing. Phagetyping wasperformed according to the

Typhimuriumdefinitive phage type104 (DT104) has been

methodsand schemes described previously (7).

animportant zoonotic pathogeninEuropeand NorthAmerica

The 144 S. Typhimurium strains were divided into 22

since 1990. DTIO4 isknown to have a wide host rangeand toresistance pattems, with the pattems resistant to four or morebe pathogenic for humanSand cattle (1 ). Cattle are considered

antimicrobials showninTable 1. Of 144 strains, 6i (47.2%)

to be an important reservoir for Salmonella Typhimurium

showed the ACSSuT+ resistance pattern. In particular,
ACSSuTand ACSSuTK were the major resistance pattems

DT104 (1‑3). But也e worldwide distribution of DT104 inlivestock,includingthatinJapan, is not wellknown. h Japan,
humannon‑typhoid salmonellosis caused by S. Typhimurium
DTIO4 isknOwn as serious problem for public health(4,5).

incattle.
As a result ofphage typing, 36 of68 (52･9%) ACSSuT+

strains were identified as phagetypeDTIO4 (Table 2)･ The

In this study, we examined the distribution ofDT104among

first DTIO4 strain detected in this study was isolated fromJapanese livestock from 1973 to 1998. Before 1990, S.

pouhyin1990,and showed a resistance pattem ofACSSuTTp･Typhimurium was thought to be prlmarily associated withThis atypical resistance patternhas also been isolated inEnglandand Wales (3). But the epidemiological relationshipinthis study was not clarified. Except for another atypicalcalf diarrhea. But after 1990, salmonellosis caused by S.

Typhimuriumamong cattleincreased considerably. Salmonella
serotypes isolated &om cattle were mainly Typhimurium, withstrain, shown as ACSSuTK isolated from cattlein1996, 34

a few Dublin. We tested the antimicrobial susceptibilityof
144 S. Typhimurium isolates, 68 0f which were resistant tofive or moreantimicrobials (ACSSuT+). These 68 strains wereTable I.Antibiotic resistance pattems ofS･ Typhimurium isolated
Bom Japanese I ivestock

further examined by phagetyping.

Res istanceThe 144 S. Typhimurium strains were isolated during theC attle Poultry Environment Total

Pattemperiod of 1973through 1998,from epidemiologicallyinde‑ACSSuTKTp

pendent clinical specimens submitted to livestock hygiene

service centers, whichare distributed throughout Japan. TheACSSuTK N

144 strains consisted of 125 strains of cattle origin, 9 of poultry,

ACSSuT TpN

and 10 &om the environment (premise 6, feeder 3,and dust

ACSSuT Tp

I). For all the strains,antibiotic susceptibilitywas evaluatedby MICs. The MICs ofampicillin(A), chloramphenicol (C),ACSSuTK

1 4 1 1 9 2 2 3 0ノ 0 5 1 ′b141

1 300 81 4 1 1 つJACSSuT

streptomycin (S), sulfamethoxazole (Su), tetracycline (T),A SSuTK N

2kanamycin (K), trimethoprim (Tp), nalidixic acid (N), andACSuTK

3norfloxacin (Nx), determined using the two‑fold serial agar
dilution method, ranged Bom 100 to 0.025 LLg/ml on SensitiV‑

ASSuTK

7ACSSuityDisk Agar(Nissui Pharmaceutical, Tokyo) according tothe Approved Standard of the JapanSocietyofChemotherapyASSuTCSSuT(6). All 6S strains which exhibited ACSSuT+ resistancepattem were further tested by phage typing and plasmid

19141Others

2 7Total

1255941

A: Ampicillin, C: Chloramphenicol, S: Streptomycln,*Corresponding author: Tel: +8 1 ‑298‑38‑781 5, Fax: +8 1 ‑298‑38‑

Su: Sulfamethoxazole, T: Tetracycline, K: Kanamycln,

7825, E‑mail: tsame@niah･affrc･go･jp

Tp: Trime也oprim, N: Nalidixic acid150Table 2･ Number ofS. Typhimurium DT I 04 isolated &om Japaneseinthe 1.990SinJapan(4,13)andthe DTIO4 strains isolatedin

livestock 198 I‑1998

仙is smdy were all highly susceptiblet tO Nx.

1981 ‑1990

1991 ‑1998

TotalSource No. of No. of No. of No. or No. of No. oftested DT104

C attleつJ 101tested DT104
40ノ 2 33l13

REFERENCE S

tested DT104

I. Besser, T. E., Gay, C. C., Gay, J. M., Hancock, D. D.,

6231

Pout try

32Rice, D., Pritchett, L C. and Erickson, E. D. (1997):

Environment

33Salmonellosis associated with S. Typhimurium DT1046$361inthe USA. Vet. Rec., 140, 75.

2. Hollinger, K., Wray, C., EvanS, S., Pascoe, S･, Chappell,S.and Jones, Y. (1998): Salmonella TyphimuriumDTIO4incattle in Great Britain. J. Am. Vet. Med. Assoc., 213,of 36 DT104 strains showed atypical resistance pattem of1732‑1733.

3. Poppe, C., Smart, N., Khakhria, R., Jhonson, W., Spika,ACSSuT

AsshowninTlable 2, cases of cattle salmonellosis associatedwith S. Typhimuriumclearlyincreasedinthe 1990S, withno
S･ Typhimuriumstrains showing ACSSuT+ resistance pattems

J. and Prescott, J. (1998): Salmonella typhimurium

isolated before 1980. From 1981 through1990, no cattle
strains ofACSSuT+ were identified as DTIO4. But from 1991

4. Matsushita, S., Konishi, N., Arimatsu, M., Kai, A.,Yamada, S., Morozumi, S., Izumlya, H., Terajima, J.andthrough1998, 3 1/49 (63.3%) were identified as DTIO4. TheseWatanabe, H. ( 1 999): Drug‑resistanceand definitive type

DT104: A virulentand drug‑resistant pathogen. Can. Vet.
J., 39, 559‑565.

results suggest that DTIO4 isanimportant cattle pathogenin

1 04 0f Salmonella serovarTyphimurium isolated &om

J叩an.

sporadic casesinTokyo, 1980‑1998. J. Jpn･Assoc･ hfect･

host‑adapted type of Salmonellaand is lackingan05antigen

Dis., 73, 1087‑1094 (inJapanese).
5. Izumlya, H., Tamura, K., Terajima, J･and Watanabe, H･(8)･ In the United States, outbreaks ofS. Typhimurium var.
Copenhageninfections linked to dairy products were reported( 1 999): Salmonella enterica serovar. Typhimuriumphage
type DT104 and other multi‑drug resistant strains inS･ Typhimurium var. Copenhagen is known as a plgeOn

Japan. Jpn. J. Infect. Dis., 52, 133･(9),andthis strainhas also been identified as DT104. Therefore,

the relationship between S. TyphimuriumVar. Copenhagen
and DTIO4inJapanwas examined uslng the presence or

6. JapanSocietyofChemotherapy (1 98 1 ): Approved methodof MIC determination. Chemotherapy, 29, 76‑79 (inabsence ofO5antigen. Among the 68 ACSSuT+ strains, 05
antigen was observedin22% (8/36) ofDTIO4 examples andin1 9% (6/32) of other strains, suggestingthat var. Copenhagen

7. Anderson, E. S., Ward, L R., De Saxe, M. J.andDe SA,Japanese).

J. D. H. (1977): Bacteriophage‑tⅥ)ing designations ofoccurs with similar舟equency in DT104 and non‑DT104

Salmonella妙himurium. J. Hyg., 78, 297‑300･

strains of S. Typhimurium.
Plasmid profiling was performed onthe 36 DTI 04 isolates

8. Smyser, C. F.and Snoeyenbos, G. H. (1972): A pigeon

usingthe medlOd described by Kadoand Liu (10). The plasmids

Copenhagen. Avian Dis., 16, 270‑277･
9. Cody, S. H., Abbott, S. L., Martin, A. A., Schulz, B･,Wagner, P., RobbinS, K., Mohle‑Boetani, J･ C･and Vugia,

host‑adapted type of Salmonella typhimurium var･

were separated by electrophoresis uslng 0.8% agarose andphotographed under UV illumination. Results of plasmid

profiling showedthat all strains retaina 90‑kb plasmid,known
as a virulence plasmid (1 1). Forty‑fourpercent (16/36) of theD. ∫. (1999): Two outbreaks of multidmg‑resistant

Salmonella serotype Typhimurium DT1 04 infections
linked to raw‑milk cheeseinNorthem Califomia. JAMA,

strains examined had a 90‑kb plasmid only, and 20 Others

281, 1805‑1810.

possessed a few additional small plasmids ranglngfrom 2 to4 kb. These plasmid pattems differed slightly &om thosedescribedina previous reportfromthe United Kingdom (12),but was in agreement with these described in a report from

10. Kado, C. I. and Liu, S. lT. (1981): Rapid procedure fordetection and isolation of large and small plasmids. ∫.

Bacterio1., 145, 1365‑1373.

the United States (1).

1 1. Jones, G. W., Rabert, D. K., Svinarich, D. M. andWb紙eld,In conclusion,these results showedthat DTI 04 strains have

H･ J･ (1982):Association of adhesive, inva苧ive, andexistedinJapanese livestock since 1990,andthat this phagevirulent phenotypes of Salmonellaりphimurlum With

type isanimportant pathogen for cattle. It is now consideredautonomous 60‑megadalton plasmids. Infect. Immun･,38, 476‑486.

to be widely distributed throughout J叩an. Most of the 36

12. Threlfall, E. J., Frost, J. A., Ward, L. R. and Rowe, B.

DT104 strains exhibited the antibiotic resistance pattem
ACSSull but one strain showed an additional Tp resistanceand another strain showed an additional K resistance. This(1994): Epidemic in cattle and humans of Salmonella
ophimurium DT 1 04 with chromosomally integrated
multiple drug resistance･ Vet･ Rec･, 134, 577･

atypical K resistance may be related tothe use of KinJapanese

13. National Institute of Health and Infectious Diseases

livestock.

This wide distribution ofDTI O4among Japanese livestock

ControI Division, Minisby ofHealthand Welfare ( 1 997):

may represent a potential public health risk. Fortunately,Salmonella, Japan, 1 994‑ 1 996. Infect. Agents Surveillancefood‑bone ilhesses associated withS. Typhimuritm decreased

Rep., 18, 51'‑52'･

16