Final answer:
The group of (+) ssRNA viruses causing gastroenteritis in various animals and humans includes rotaviruses, adenoviruses, noroviruses, and astroviruses, with noroviruses being particularly common in causing outbreaks.
Step-by-step explanation:
The group of (+) ssRNA viruses that have been isolated from a variety of animals including birds, cats, dogs, pigs, sheep, cows, and humans, and are known to be a major cause of gastroenteritis, are the rotaviruses adenoviruses, noroviruses and astroviruses. These viruses are especially common in children and are usually transmitted through the fecal-oral route. Notably the norovirus is one of the most common and well-known among these for causing outbreaks of gastroenteritis.
Gastroenteritis and Viral Causes:
For instance, rotaviruses belong to the family Reoviridae and are double-stranded RNA viruses, whereas adenoviruses are non-enveloped viruses that can cause respiratory illnesses but also gastroenteritis. Both rotaviruses and astroviruses are particularly notable for their impact on infants and children. These viruses are transmitted through contaminated food or water and diagnosis is typically made by analyzing stool samples. Treatment primarily involves supportive care such as rehydration and electrolyte replacement.