Laboratory and Epidemiology Communications

Outbreak of Enterohemorrhagic Escherichia coli 0 1 57

Mass Infection Caused by "Whole Roasted Cow"
Junko Yamamoto, Atsushi Ishikawa, Mikiko Miyamoto, Takashi Nomura* ,Masako Uchimura] and Kenji Koiwai.
Funabashi Health Center, Chiba Prlefectwe,

Minatocho 2‑10‑18, Funabashi, Chiba 273‑0011 andJpublic Health Laboratory, Chiba Prefectuyle,
Nitonacho 666‑2, Chuo‑ku, Chiba 260‑8715

Communicated by Kunihiko Masukawa(Accepted June 1, 2001)

EHEC 01 57 case to Funabashi Health Center. The investlga‑On 28 October 2000, Chiba Prefecture experienced a mass
infection of enterohemorrhagic Escherichia coli (EHEC)
0157 at a live‑stock festival. There were 58 infected cases,tion conducted on the same day revealed that all the patients

had ingested the whole roasted cow provided at the festival.

The causative agent EHEC 0157 was traced to the whole

As possibilities other than the roast as a cause remained, pulsed
fleld gel electrophoresis (PFGE) analysis of the isolates was

30 0f which exhibited symptoms.
roasted cow which was served to several hundred of theperfわrmed immediately. At the same time, Funabashi Cityparticipants.Asthe incident relates to both food poISOnlng

opened a consultation station to the general public which

and infectious disease which are under different regulatory

side. As the festival provided unrestricted accessibility andprovided examination of stool specimens on request. On 1 3
November, flVe SPeCimens including the above three were
found to have identical PFGE pattems, and all of the reported

several hundred people participated, it was difrlCult to identify

ten patients including the above three were fわund to have

who ingested the roast. The possibility of unnoticed cases

Ingested the roast. The culprit fわod was detemined on theschemes in Japan, there was some difrlCulty on the regulatory

and secondary spread of the infection remained throughout

same day to be the whole roasted cow. MicrobiologlCal

the investlgation which lasted until December 22.

investlgation of the commercial route or the meat and thatremainlng at the festival was unable to isolate EHEC 0157,
however. The PFGE pattem of the isolates was one which
had not been reported before (information from National
Institute of Infectious Diseases).

The incident came to the notice of the regulatory authority

on November 8. On that day, three different clinics reported an*ComSpOnding author: Present address: Public Health Promo‑

The whole roasted cow that caused the incident wastion, Chiba Prefecture, Ichibacho 1 ‑ 1 , Chuo‑ku, Chiba 26018667,

E‑mail: t.nmr5@ml.pref.chiba.jp

prepared in the fbllowlng Way. A halfof a cow whose viscera

88inducible genes (3)･ It is now speculated that p44 is possibly

was inoculated into chimpanzee #1310, #429, and #125,

one of the mediators involved in the antiviral action of inter‑

respectively. All of the chimpanzees developed hepatitis asferon.

evidenced by the elevated level of semm ALr; the peak wasRecently, GB virus C (also called as hepatitis G virus)

at week 2 fわr #1310, at week 12 fわr #429, and at week 5 fb∫(GBV‑C/HGV), which is closely related to but distinct fromHCV, was discovered. Although they share little sequencehomology, HCV and GBV‑C/HGV have a qulte Similar genetic#125.

organization, With the exceptlOn that the latter almost lacks

for the present assays. For both chimpanzees, all of the serum

sequences encoding a core protein. We were interested toknow

samples were negative for HCV RNA as measured by RT‑PCR, as well as anti‑CIOO HCV antibody as measured bySerum samples and liver biopsy specimens collected atintervals from chimpanzees #429 and #125 Were available

if GBV‑C/HGV induces p44, as both vimses presumably
replicate via double‑stranded RNA replicative intermediate,ELISA, throughout the obseⅣation period or35 weeks. GBV

C/HGV RNA, as detected by RT‑PCR with pnmers detectlng

an interferon inducer.

When we retrospectively examined samples from thethe 5 'non‑coding reglOn Of the viral genome, became transiently

NANBHV transmission studies conducted in the 1980S, wepositive at 1‑ 2 Weeks and then continuously positive at 10‑

35 weeks in chimpanzee #429 (Fig. lA)･ 1n chimpanzee #125,*Corresponding author: E‑mail: yshimizu@ri.imcj.go.jp

GBV‑C什IGV RNA was detected at 3‑8 weeks, then reappeared

89