Canine Astrovirus: An Emerging Cause of Viral Enteritis in Puppies"

Introduction

Canine Astrovirus (CaAstV), also known as Small Virus, is a small, non-enveloped, single-stranded RNA virus. It is often present in co-infections with Parvovirus or Coronavirus and is one of the main culprits in the Canine Infectious Diarrhea Complex. It is also one of the oldest viruses but still considered a "sneaky" disease that owners often do not even think of.

1. the name "Astrovirus" comes from the Greek word 'astron', meaning star, because of its shape under a microscope. 

Transmission and Pathogenesis

Canine Astrovirus is mainly spread by the fecal-oral method. Once it is ingested, it infects the mature enterocyte cells located at the tips of the microvilli in the intestine, leading to:

Malabsorption

Osmotic Diarrhea

Villous Atrophy (shortening of the microvilli)

Clinical Signs

It is often subclinical in adult dogs but in puppies or immunocompromised dogs, the symptoms include:

Watery Diarrhea

Vomiting

Lethargy and Anorexia

Growth Retardation

Diagnosis: How to Detect It?

​The symptoms are quite common with other GI infections, thus laboratory confirmation is a must:

​RT-PCR: 

The most sensitive test for viral RNA in stool samples.

​Electron Microscopy:

Traditionally used to detect the 'star-like' shape of the virus.

​ELISA:

Some laboratories use this test to detect viral antigens.

​Treatment and Management

​There is no specific antiviral treatment for CaAstV. The focus of management is on Supportive Care:

​Fluid Therapy:

To avoid dehydration due to diarrhea.

​Probiotics: 

To maintain a healthy GI tract.

​Bland Diet:

 Easily digestible food to rest the GI tract.

​Disinfection: 

Astrovirus is a hardy virus, thus bleach is recommended for disinfection in kennels