Jpn. J｣nfect. Dis., 54, 2001

Laboratory and Epidemiology Communications

Enterohemorrhagic Escherichia coli 026 Outbreak Caused byContaminated Natural Water Supplied byFacility Owned by Local Community
Ken Hoshina*,Asao ltagaki, Ryutarou Seki, Kazuko YamamotoI, Shou‑ichi MasudaI,
Tathumori Muku] and Naohisa Okada]Sh imane Prefectural Institute of Public Health and EnvitlOnmental Science,

Nishihamasada‑cho 582‑1, Matsue, Shimane 690‑0122 andJshimane lzumo Health and WelfaTle Center:
Enya‑cho 223‑1, 1zumo, Shimane 693‑0021
Communicated by Hiroo lnouye(Accepted January 25, 2002)

Clinical manifestation of food poISOnlng Caused byenterohemorrhagic Escherichia coli (EHEC) 0 1 57 usually

local communlty for other uses such as bathing, washingrequlreS 4‑8 days of incubation.Asa result of this long Incuba‑

dishes, etc･ Two sources of water were used for the corrmunity
facility; a mountain stream and a disused tunnel. Water fromtion, the suspected foods have often been discarded by thethe mountain stream was filtered through a simple style filter

time the investlgation takes place, and identifying the culprit

system uslng Sand and pebbles, Combined with water fromfood is difficult. In a recent EHEC 026 Outbreak in Shimane

the tunnel, and distributed to the community Of 37 families,

Prefecture, however, We were able to trace the source of thecomprised of 141 residents including the patient (Fig. 1).

infection to natural water supplied by a water facilityrun by

Water specimens from the source‑Polnt Of the mountaina local communlty.

stream and from tank #1, where water from the tunnel was

On 28 June 2001, the local health and welfare center
received a report ofisolation ofEHEC 026 in the case ofa 2‑

taken from the mountain stream, upstream of the source‑polnt,stored (Fig･ I), were positive for EHEC O26･ Water specimens

yeaト01d girl with hemo血agic dia汀hea. An epidemiologlCal

from the water in tank #2, from the innow of the filteredinvestlgation was initiated imediately. It was fわund that themountain stream water to the distribution tank, and from thepatient's family used the clty Service water as potable water,water stored in the distribution tank (Fig. 1) were negative.

and used natural water supplied by a water facilityrun by theA communlty gathering was called, and infわrmation on

the incidence was distributed. The residents were asked not*ComSpOnding author: Fax: +8 1‑852‑36‑6683, E‑mail: hoshina

to use the communlty‑Supplied water. The water sources were@j oho‑shimane. orjp

immediately disinfected to prevent further spread of infec‑

247

Jpn. J. Infect. Dis., 54, 2001
Mountain Stream → Filtration Svstem →Distribution Tank

Disused Tunnel‑A pipe LineA Zonellfamilies‑迫"I ‑Tank#2 剩a Pipe Line｢ﾒﾒ(1)***B Zone
15 families** (5)C ZoneC Pipe Line

11families(4)

辛 Positive fわr EHEC 026** Zone in which the patient's family lives.
*** Figures in parentheses indicate the number ofEHEC 026 carriers.

Fig. L Distribution ofwatcr supplied by the communitywatcr facility.

tion. Investlgation or the use of the communlty Water andwas a possibility. Actually, Sudo et al. (5) reported isolation

bacteriologlCal examination of fecal specimens of the residents

ofEHEC from two among 53 antelopes examined (3.8%)I It
should be noted that there was a heavy rainfall in the reg10nwere also conducted.

For detection ofEHEC, 6124 h cultureinTBS broth(Tryptosoyof the outbreak several days before the incidence. Inflow ofabroth) at 420C followed by culture on the CTR‑Mac and DHL

large amount of contaminated water to the facility may haveselection plates was adopted. The suspected colonies wereresulted in water treatment failure.

further submitted to biochemical tests, PCR amplification ofThis article appeared in Infectious Agents Surveillance
Report (lASR), vol. 22, no. 12, p. 321, 2001 in Japanese.

the genome, and serologlCal diagnosis.
There were no dia血eal patients other than the above一mentioned patient among family members of the patient or

the residents of the community. EHEC 026 was isolatedfrom

REFERENCE S

fecal specimens of five (three adults and two children) amongnine family members and from fecal specimens of five among

1. National Committee fわr Clinical Laboratory Standards

1 16 residents who used the mountain stream water. All 12( I 994): Performance Standards for Antimicrobial Suscep‑

isolates, one isolate from the patient, 10 isolates from thetibilityTesting. MIOO‑S51 National Committee for Clini‑carriers, and one isolate from tank #1 , were EHEC 026:Hl 1.
Antibiotic sePsitivity was tested by the KB method (1 ) byuslng kanamycln, CIPrOfloxacln, tetraCyCline, gentamicin,

2. 1zumlya, H., Terajlma, J., Wada, A., lnagaki, Y., Itoh, K.,
Tamura, K. and Watanabe, H. ( 1997): Molecular typing

fosfomycln, Sulfamethoxazole‑trimethoprlm, nalidixic acid,of enterohemorrhagic Escherichia colt 0 1 5 7:H7 isolates

cal Laboratory Standards, Villanova, Pa.

chloramphenicol, cefbtaxim, ampicillin, trimethoprlm, andin Japan uslng Pulsed‑field gel electrophoresis and phage

streptomycln. The isolates were resistant to kanamycln,typlng. ∫. Clin. Microbio1., 35, 1675‑1680.

tetracycline, ampicillin, and streptomycin. Not many lnCidences
or multi‑antibiotic resistant EHECs have been previously

3. 1to, T. and Kai, A. (1997): EHEC 0157 hfection and food.

reported.

4. Koyama, T., Nakamura, T., Hayashi, E. and Fujimoto,K.(1999): EHEC 0157 food poisoning outbreak causedby drinking water h Nagano Prefecture. Infect. Agents

Jpn. ∫. Food Microbio1., 388, 275‑285 (in Japanese).

Pulsed‑field gel electrophoresis analysis Was Perfomed
according to the method recommended by the National
Institute of Infectious Diseases (2) on Xba 1 ‑digested DNAmaterials. All isolates showed an identical pattem.
The source of the EHEC 026:Hl 1 that caused the present

SuⅣeillance Rep., 20, 298‑299 (in Japanese).

5. Sudo, M. and Ohtani, K. (2000): incidence ofdiarrheal
pathogens carried by wild antelopes and its relation towater pollution oftheriver. J. Jpn. Vet. Med. Assoc., 54,

outbreak remained obscure, as in previous wateトbome cases

569‑574 (in Japanese).

(3,4). Giventhat human access to the water source facility
was rare, contamination of the water by wild animal excrement248