Conclusion
Parvo is a virus that affects both humans and animals, but is more common in puppies. Puppies with this virus are usually very sick dogs because the condition is usually accompanied by serious symptoms. Contacting a vet immediately if you experience any of the symptoms is the best bet for getting a successful treatment.
Reference:
[1] https://www.akc.org/dog-breeds/rottweiler/
[2] https://www.akc.org/dog-breeds/doberman-pinscher/
[3] https://www.akc.org/dog-breeds/american-staffordshire-terrier/
[4] https://www.akc.org/dog-breeds/english-springer-spaniel/
[5] https://www.akc.org/dog-breeds/german-shepherd-dog/
[6] https://www.akc.org/dog-breeds/labrador-retriever/
[7] https://www.petmd.com/cat/conditions/infectious-parasitic/c_ct_feline_panleukopenia
[8] https://www.akc.org/expert-advice/health/lethargy-in-dogs-what-you-need-to-know/
[9] https://www.webmd.com/pets/dogs/vomiting-dogs-causes-treatment
[10] https://www.northeast-vet.com/site/pet-care-blog-plains-vet/2021/08/30/diarrhea-in-dogs-common-causes-how-to-stop-it
[11] https://vcahospitals.com/know-your-pet/weight-loss-abnormal-in-dogs
[12] https://www.goodrx.com/pet-health/dog/dog-depression-signs#:~:text=Dogs%20can%20get%20depression,%20and,unusually%20clingy%20or%20needy%20behavior.