are you feeding raw ? it is usually due to coming in contact with dead animal, etc - here is some more info on it as my friends yorkie gets it alot and once they get it once they are susceptible to getting it again
Hemorrhagic Gastroenteritis-HGE Canine Hemorrhagic Gastroenteritis (HGE) ~ Pawprints and Purrs, Inc.
this is from a friend of mine below :
Not contagious at all......and yes HGE starts MOST times with vomitting.
I know I have passed this article on a few times.
DogCare - Hemorraghic Gastroenteritis
HGE is not contagious. It primarily affects younger dogs, but may be seen in all ages. Toy and medium-sized dogs appear to be at increased risk. The disease is characterized by a sudden onset of vomiting, dehydration and profuse bloody diarrhea. As the condition progresses, the dog will eventually go into a state of circulatory collapse * that is, the veins will collapse due to dehydration and loss of fluid from the intestinal tract. If the disease is untreated, death will come from dehydration, hypothermia and shock.
I have been thru this many, many times...Lucy had it just last month. We cannot find the cause, so the treatment is given immediately. My vet knows I know my dogs and the symptoms of this.
If caught early they are fine...I do believe many dogs are tested to death...this condition requires immediate treatment of fluids, no solid foods, and a course of anti diarrhea/antibiotic medication...mine are always put on Amphorol and respond very quickly.
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Wikipedia (Links)
Hemorrhagic_gastroenteritis
HGE http://lapublichealth.org/vet/docs/2...ortingForm.pdf http://wvc.omnibooksonline.com/data/.../2005_V347.pdf