Shih-tzus do not shed. Just like people, they have hair. When we comb our hair some hair comes out in the comb; however, they do not shed. They are highly recommended for people with allergies, and are also good with children. I was a breeder for 20 years of this particular breed. They were bred for companionship. They originated in China.
I can back Thmpsn on this as I've had a Shih tzu and he did not shed. Only a little hair in the brush but Ziggy had long hair and I brushed him every day to keep it nice. No dog hair to vacuum or sweep up!
I don´t know but you should ask a local vet about your concerns
Not a lot.
Yes. This is the time of year when most of them are groomed with shorter hair due to the heat.