# 5600
The expanding outbreak of EHEC (or STEC Shiga-Toxin Producing E. Coli) in Europe has produced an avalanche of news articles and analysis. Most days we are seeing literally scores of updates.
Both Crof at Crofsblog and the newshounds at FluTrackers (see news forum Escherichia coli (E. Coli), Enterohemorrhagic Escherichia Coli (EHEC), Hemolytic-Uremic Syndrome) have been providing outstanding hour-to-hour coverage of this story.
Of course, I haven’t been ignoring the crisis. My coverage, however, has been focused less on the breaking news aspects, and more on research updates (CDC, ECDC, WHO) and background information.
Today, an update and a well-done FAQ from WHO Europe.
EHEC outbreak: Update 6 (04-06-11)
04-06-2011
These are the current figures for the outbreak. Enterohaemorrhagic Escherichia coli (EHEC) and haemolytic uraemic syndrome (HUS) have exclusive notification categories, so case numbers should not overlap. The figures in any rapidly evolving outbreak are provisional, however, and subject to change for a variety of reasons.
- As of 02 June at 15:00 CET, Germany had reported 520 cases of HUS, including 11 fatalalities: 50 more than the previous day. 70% of the cases were in females and 89% in adults aged 20 years or older.
- As of 02 June 15:00 CET, 1213 cases of EHEC infections (without HUS) had been reported in Germany, 6 of them fatal: 149 more than the previous day. Of those cases, 61% were in females, and 88% in adults aged 20 years or older. Case onset dates for EHEC ranged from 1 to 30 May.
- As of 03 June 18:00 CET, 11 other European countries (see table) had reported a total of 31 HUS (1 fatal) and 70 EHEC cases (0 fatal).
- In addition, the Centers for Disease Control and Prevention (CDC) in Atlanta, United States of America had previously published information on two cases of HUS in the United States that were linked to this outbreak.
- All but 1 of the above HUS and EHEC patients had travelled to or from Germany during the incubation period for infection, typically 3–4 days after exposure (range 2–10 days). An increasing number of cases is laboratory confirmed as EHEC serotype O104:H4.
Since various agencies and news organizations around the world have elected to use different terminology to describe this outbreak, following this story can sometimes be a bit confusing.
The World Health Organization has put together a good FAQ (Frequently Asked Questions) file on the outbreak, which may serve to clear up some of the confusion.
Frequently asked questions on the EHEC infection outbreak in Germany
Background
1. What are EHEC and HUS?
Enterohaemorrhagic Escherichia coli (EHEC) is a human pathogenic E. coli bacterium that is able to cause haemorrhagic colitis (bloody diarrhoea), which sometimes develops into haemolytic uraemic syndrome (HUS). HUS is a life-threatening disease that causes kidney damage and is a severe complication of EHEC infection. EHEC is so-called Shigatoxin-producing E. coli (STEC), also known as verocytotoxin-producing E. coli (VTEC). Animals can carry other types of STEC/VTEC in their intestines that are not necessarily pathogenic for humans.
2. Surely E. coli is very common, so why the concern?
Yes, E. coli is a common bacterium that is found in the intestines of humans and warm-blooded animals. Nevertheless, this particular strain, a rare serotype of EHEC (namely E. coli O104:H4), is severe, and has caused much illness and some deaths in Germany. Cases have also occurred in 11 other countries, all of whom had travel links to, or residence in, Germany, except for one case still under investigation. This is a significant outbreak of HUS. It is affecting mostly women and mostly people over 20 years of age, which is unusual. As the source of the outbreak has not been found, it is difficult to say how long it will last.
3. Is this unique?
The serotype of EHEC, O104:H4, isolated from cases in the EHEC infection outbreak in Germany, is a rare one, seen in humans before but never in an EHEC outbreak. This has been confirmed by the WHO Collaborating Centre for Reference and Research on Escherichia and Klebsiella, the Statens Serum Institut in Denmark. The molecular/genetic features of this pathogen are important in helping authorities to identify cases in other countries that could be associated with the outbreak in Germany and to identify the source of the outbreak. While epidemiological and laboratory investigations continue, the source of the outbreak still remains unknown.
4. How would you describe the EHEC outbreak currently happening in Germany?
Germany is experiencing a significant outbreak of EHEC, a highly pathogenic bacterium subgroup of STEC. A minority of cases are presenting complications with HUS, a life-threatening disease characterized by acute kidney failure (uraemia), haemolytic anaemia, and a low platelet count (thrombocytopenia).
5. When was the last EHEC outbreak?
Every year there are EHEC outbreaks in different parts of the world including Europe, sometimes involving HUS and even deaths, but the number of affected people is very much lower than what Germany is now experiencing. In 1996, the world’s biggest recorded outbreak was registered in Japan and included over 10 000 infected cases.
6. How many countries are involved in the current outbreak?
Cases have now been notified from 11 countries in addition to Germany: Austria, the Czech Republic, Denmark, France, the Netherlands, Norway, Spain, Sweden, Switzerland, the United Kingdom and the United States of America. These are typically people who have recently visited northern Germany or, in one case, had contact with a visitor from northern Germany who was an EHEC case.
7. Do people outside Germany need to worry?
Most of the cases are linked to the northern part of Germany, and investigations are taking place to define the exact geographical areas where transmission is occurring. There is no indication so far of confirmed domestic or secondary infection in other countries.
