EHEC By Marie and Alicia

What is it? E. coli is a bacterium that is found in the intestine of humans E. coli is a bacterium that is found in the intestine of humans EHEC = enterohaemorrhagic escherichia coli EHEC = enterohaemorrhagic escherichia coli  strain of E. coli  Type : O104:H4  first recognized in 1982  in Germany 2011

Sources reservoir of bacterium in ruminants ( e.g cattle or camels) reservoir of bacterium in ruminants ( e.g cattle or camels) contaminated food like raw or uncooked meat contaminated food like raw or uncooked meat person-to-person contact: oral-faecal route person-to-person contact: oral-faecal route (asymptomatic carriers) (asymptomatic carriers) contaminated water (can survive for months) contaminated water (can survive for months) in this case probably contaminated vegetables which got in contact with faeces of infected animals in this case probably contaminated vegetables which got in contact with faeces of infected animals

Pathogenesis

Incubation period: 3-8 days; infectious dose may be only 10 bacteria Incubation period: 3-8 days; infectious dose may be only 10 bacteria in the intestines bacteria attach to the villi and produce Shiga-like toxins in the intestines bacteria attach to the villi and produce Shiga-like toxins toxins block protein synthesis and induces cell death toxins block protein synthesis and induces cell death also enter blood vessels and attach to their walls causing the breakdown of RBCs and platelets also enter blood vessels and attach to their walls causing the breakdown of RBCs and platelets

HUS hemolytic-uremic syndrome hemolytic-uremic syndrome closely associated with EHEC and other GIT-infections closely associated with EHEC and other GIT-infections 10-20% of patients with EHEC infections develop this syndrome 10-20% of patients with EHEC infections develop this syndrome mortality rate with intensive care is 3-5% mortality rate with intensive care is 3-5% affects especially people with less distinct immune system affects especially people with less distinct immune system

Symptoms fever fever nausea/ vomitting nausea/ vomitting weakness weakness abdominal pain abdominal pain patients with HUS: diarrhea (progresses to bloody diarrhea) diarrhea (progresses to bloody diarrhea) abdominal cramps abdominal cramps

Clinical findings small blood clots small blood clots internal bleeding internal bleeding anemia and thrombocytopenia anemia and thrombocytopenia dyspnea (breathing difficulties) dyspnea (breathing difficulties) inflammation of the pancreas inflammation of the pancreas kidney failure kidney failure anuria anuria neurological disorders neurological disorders

Treatment EHEC EHEC –most victims recover within 10 days –bacterium is killed at 70°C –no antibiotics stimulate toxin production –hygiene HUS HUS –intensive care –transfusion of RBC and platelets –dialysis –medication like corticosteroids

EHEC in Germany EHEC infections occur worldwide EHEC infections occur worldwide in Germany about 1000 every year, usually affecting small children in Germany about 1000 every year, usually affecting small children big outbreak in summer 2011 from may to july big outbreak in summer 2011 from may to july

4335 EHEC infected people, 855 HUS infected people 2987 people with acute gastroenteritis, 48 deaths 4335 EHEC infected people, 855 HUS infected people 2987 people with acute gastroenteritis, 48 deaths 68% of patients were females and most affected people were adults 68% of patients were females and most affected people were adults fenugreek seeds were identified as source for the infection fenugreek seeds were identified as source for the infection after the distribution was ceased, there were no new infections associated with the vehicle after the distribution was ceased, there were no new infections associated with the vehicle

Consequences Affected people: – –dialysis throughout life – –need of donor organs Economy: – –farmers lost income – –European Commission covered the loss by paying 226 million € to the agricultural market – –another 12 million € for the study of the pathogen

References: References: – – – – Pictures: Pictures: – jpg jpghttp://mhstatic.de/fm/1/thumbnails/SH_ehec_Bakterien_800.jpg jpg – – gesundheit/pic/ehec_faelle_bayern_ gif&imgrefurl= / gesundheit/pic/ehec_faelle_bayern_ gif&imgrefurl= / gesundheit/pic/ehec_faelle_bayern_ gif&imgrefurl= /