Download E coli

COMMUNICABLE DISEASE MANUAL POLICIES/PROCEDURES
ESCHERICHA COLI 0157:H7
(Shiga Toxin Non-0157:H7 and
Unspecified E. coli)
OBJECTIVE:
Control and management of E. coli 0157:H7
DESCRIPTION:
A bacterial disease commonly manifested by an acute enterocolitis, with sudden
onset of headache, abdominal pain, diarrhea, nausea, sometimes vomiting, low
grade fever and muscle aches. Watery (often bloody) diarrhea is the main
characteristic. Illness may be complicated by Hemolytic Uremic Syndrome
(HUS) or Thrombotic Thrombocytopenic Purpura (TTP).
Asymptomatic
infections also may occur.
E. coli 0157:H7 is a gram negative bacilli that is a common inhabitant of the
human gastrointestinal (GI) tract. There are many different strains of E. coli.
Not all E. coli are serogroup 0157, and not all E. coli 0157 are serogroup H7.
Incubation period for gastroenteritis is from 14 to 50 hours after the bacteria has
been ingested. It takes relatively low numbers of this organism to cause
symptomatic illness and victims are contagious in the early stage before
becoming symptomatic.
See Region 5 CD Tip of the Month (01/09): Shiga Toxin producing Escherichia
coli (STEC) and CDC Case Definition.
EQUIPMENT:
MDSS User Manual and disease specific form found in MDSS MDCH
Microbiology/Virology Test Requisition, instructions for collection of stool, enteric
Cary Blair medium and Ova & Parasite stool specimen containers, and
educational data. MDCH website at www.michigan.gov/cdinfo and CDC website
at www.cdc.gov/diseasesconditions/az.
POLICY:
Legal Responsibility: Michigan's communicable disease rules of Act No. 368 of
the Public Acts of 1978, as amended, being 333.5111 of the Michigan Compiled
Laws. Follow-up time 24 hours post referral AND ENTER INTO MDSS
WITHIN 24 HOURS OF RECEIPT OF REFERRAL.
PROCEDURE:
A.
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Case Investigation
1.
Referral received per phone
automatically through MDSS.
call,
laboratory
results,
or
2.
Document all case investigation proceedings.
3.
Contact MD and/or client to start process of completing disease
specific form in MDSS.
4.
If more than three (3) cases are reported to the Health
Department (excluding immediate family contacts) report to CD
Supervisor who will then report to Medical Director and State
Health Department as necessary
B.
C.
Lab Criteria for Diagnosis:
1.
Cultures of stool, blood, urine and material from foci of infection,
as indicated by the suspected E. coli syndrome, should be
obtained.
2.
Collect stool specimen in the Cary Blair Medium Para-Pak C & S
collection containers.
3.
MDCH LABELS - ALL SPECIMENS MUST BE LABELED, ALL
LAB SLIPS NEED TO BE COMPLETED IN DETAIL, AND ALL
MAILING LABELS NEED TO BE PLACED PROPERLY ON
CONTAINERS. LAB SLIPS NEED TO ACCOMPANY ALL
SPECIMENS. HEALTH DEPARTMENT WILL PAY POSTAGE
FOR CONTAINERS. CONTACT OFFICE SECRETARY.
Case Classification:
1.
Suspected:
2.
Probable:
A case of postdiarrheal HUS or TTP.
a. A case with isolation of E. coli O157 from a clinical
specimen, pending confirmation of H7 or Shiga toxin or,
b. A clinically compatible case that is epidemiologically linked to
a confirmed or probable case.
3.
D.
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Confirmed:
A case that is laboratory confirmed by:
a.
Isolation of Escherichia coli O157:H7 from a specimen or,
b.
Isolation of Shiga-toxin non-E. coli O157
c.
Isolation of Shiga-toxin E. coli unspecified
Control Measures:
1.
Encourage household members who are symptomatic or high-risk
to submit stool specimen. High-Risk is defined as contact to a
confirmed or suspected case, work at or attend a day care, food
handling, or patient care.
2.
Thoroughly cook all foodstuff derived from animal sources,
particularly poultry, beef, pork, egg products and meat dishes.
3.
Wash raw vegetables thoroughly before eating.
4.
Educate food handlers and food-preparers on the importance of
hand washing before, during and after food preparation; and on
the importance of refrigerating food, maintaining a sanitary
kitchen, and protecting prepared foods against rodent and insect
contamination. People with diarrhea should be excluded from day
care, patient care and food handling.
E.
5.
Foodworker exclusion/restriction: STEC cases with duties as
foodhandlers are specifically required under the Michigan Food
Code to be excluded/restricted until certain conditions are met.
STEC has a low infectious dose, and can easily be transmitted via
the foodborne route as well as other routes. CD Staff will work
together with EH staff to ensure appropriate measures are taken.
See Food Employee Foodborne Guidelines, from MDA and 2005
Food Code from Federal Dept. of Agriculture
6.
Wash hands, knives, and cutting boards after handling uncooked
foods.
7.
Adequately cook or heat-treat, including radiation pasteurization,
animal-derived foods prepared for human consumption.
MDSS Case Reporting:
1. Complete case investigation using the disease specific forms located in
MDSS. (See MDSS User Manual for entry instructions.) If follow-up
stools are needed, keep case active until all results have been returned
and documented in MDSS. If two, or more, confirmed cases of E. coli
0157:H7 from different households are discovered, complete one MDSS
form for Unusual Outbreak or Occurrence in addition to completing the
MDSS disease specific form for each case. A CDC 52.13 form needs to
be completed for an outbreak of E. coli 0157:H7 involving any mode of
transmission. The CD Supervisor and Environmental Health Director will
coordinate the completion of this form.
2. Notify CD Supervisor that the case report is ready for review. PHN will be
notified if corrections are needed prior to closing case in MDSS.
3. CD Supervisor reviews case for completeness and closes MDSS case
report.
REFERENCES:
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Current Red Book
Current Control of Communicable Diseases Manual
Current disease specific “Fact Sheet”
Websites: www.cdc.gov/diseasesconditions/az/a.html
www.michigan.gov/cdinfo
CD Tip of the Month (1/09):
Shiga toxin-producing Escherichia coli (STEC)
Tip 1: STEC-specific interviewing The incubation period for STEC is 2-10 days (median of 3-4 days)
— longer than many other enteric illnesses. Because the standard three-day meal history will not reliably
capture the exposures of interest for suspect STEC cases, a seven-day meal history is recommended.
Specifically ask whether the case consumed common high-risk items: ground beef, sprouts, raw juices, raw
milk, leafy greens; collect details on those exposures, including brand information and where purchased. Since
the food history section of the pdf form only provides space for a 3 day history, additional food history
information can be placed in the comments section of the MDSS case investigation form/pdf form. An extended
questionnaire is available for use that incorporates these suggestions (attached). This questionnaire has been
used often in past STEC outbreak situations (including the 2008 ground beef and lettuce outbreaks), and is
especially recommended if you see possible clustering of suspect cases in your jurisdiction. If you choose to
use this questionnaire, please note the date when the STEC Extended questionnaire was administered in the
comments section of the case investigation form/pdf form.
Tip 2: Laboratory confirmation of STEC cases Isolation of Shiga toxin-producing Escherichia coli
from a clinical specimen (i.e culture) is required for a case to be classified as confirmed. Some clinical
laboratories perform screening tests for shiga toxin instead of culture. The MDCH laboratory performs
confirmatory culture testing of specimens, as well as serotyping (O157 vs. non-O157), toxinotyping (STX1
and/or STX2-production), and pulsed-field gel electrophoresis (PFGE). If you do not see confirmatory results
reported into the MDSS, it may be necessary to follow up with the specimen submitter to see whether the
specimen was forwarded to MDCH, or whether it may have tested negative at the state lab. Refer to the CDC
case definition for other case classification information:
http://www.cdc.gov/ncphi/disss/nndss/casedef/shiga_current.htm
Tip 3: Foodworker exclusion/restriction STEC cases with duties as foodhandlers are specifically
required under the Michigan Food Code to be excluded/restricted until certain conditions are met. STEC has a
low infectious dose, and can easily be transmitted via the foodborne route as well as other routes. Work with EH
to ensure appropriate restriction/exclusion of foodworkers with STEC infection. Food Employee Foodborne
Illness Guidelines (MDA)
http://www.michigan.gov/documents/mda/MDA_FdEmplFBIGuidePoster_255329_7.pdf 2005 Food Code (FDA)
http://www.cfsan.fda.gov/~acrobat/fc05-2.pdf
Tips were provided by:
Sally Bidol and Katie Sheline
(517-335-8165)
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