Final answer:
Canine parvovirus (parvo) can survive in the environment for up to a year, making it a particularly resilient infectious agent.
Step-by-step explanation:
The infectious agent that can survive in the environment for up to a year is canine parvovirus (parvovirus). Parvo is known for its extreme durability in the environment and its resistance to many common cleaners and disinfectants. This virus causes a severe and potentially fatal disease in dogs, especially puppies, characterized by gastrointestinal symptoms. Due to its hardy nature, special care must be taken when disinfecting areas that have been exposed to the virus.