|
Cause:
Shiga toxin-producing E. coli strains (STEC)
including E. coli O157:H7.
Illness and treatment:
Symptoms include abdominal cramping and severe or bloody
diarrhea, usually without fever. Serious complications
include hemolytic uremic syndrome (HUS) or thrombotic
thrombocytopenic purpura (TTP). Most persons will recover
without treatment. Treating EHEC diarrhea with antibiotics
may increase the risk of developing HUS.
Sources:
Cattle are the most
important source, although other animals including deer and
horses may also carry EHEC. Other known sources are
unpasteurized milk, undercooked ground beef and more
recently, contaminated raw produce. There can be
person-to-person transmission, but most cases are due to
ingesting contaminated food or water.
Additional risks:
Children under 5 years
of age are diagnosed most frequently and are at the greatest
risk of developing HUS.
Prevention:
Wash hands thoroughly after
contact with farm animals, visiting farm environments, and
handling raw meat. Thoroughly cook ground beef and venison
and wash preparation areas to avoid contaminating other
foods. Wash produce thoroughly before eating.
Recent Washington trends:
For the past several years there have been about 130 - 190 reports
each year. EHEC has a seasonal pattern. Most cases occur
during summer and fall months.
2008:
189 cases were reported (2.9
cases/100,000 population) with one death. Cases were most
frequently diagnosed in children ages 1 to 4 years of age.
Hemolytic uremic syndrome as a complication of EHEC was
reported in 12 cases. 21 (12.8%) of all confirmed and
serotyped EHEC cases were non-O157:H7 (8 O26:H11; 7 O103:H2;
2 O121:H19; one each O26:NM, O103:H11, O111:NM, and
O145:NM).
Purpose of Reporting and
Surveillance
-
To determine if there is a
source of infection of public health concern (e.g.,
contaminated ground beef) and to stop transmission from such
a source.
-
When the source of infection
appears to pose a risk to only a few individuals (e.g., a
private water supply), to inform those individuals how they
can reduce their risk of exposure.
-
To assess the risk of the case
transmitting infection to others, and to prevent such
transmission.
-
To identify outbreaks and other
undiagnosed cases.
Legal Reporting Requirements
-
Health care providers:
immediately notifiable to local health jurisdiction.
-
Hospitals: immediately
notifiable to local health jurisdiction.
-
Laboratories: identification
of Shiga toxin-producing organism notifiable to local health
jurisdiction within 2 workdays; submission of stool specimen
or isolate to the Washington State Department of Health
Public Health Laboratories required.
-
Local health jurisdictions:
notifiable to DOH Communicable Disease Epidemiology Section
within 7 days of case investigation completion or
summary information required within 21 days.
Last update
November 2009 |
