You need to stay positive, also during these times. 
The basics are good, they just need to follow-up these basics with the visitors. If you do this on several visibile keypoints, the visitors will remind (and understand) all these precautions better.
Just as they do in Pairi Daiza. I didn't encounter big problems there, thanks to the stewards and the visibile markings on the ground in the whole park. Or as they do in Monde Sauvage, with a very simple one-direction walkway and a lot of signs.
If you want to avoid any other people in a Zoo, the parks as Forestia or Caves of Han are maybe a good solution for you. Staying home forever isn't the solution if you want to stay healty. You also have to come out and enjoy!
The basics are good, they just need to follow-up these basics with the visitors. If you do this on several visibile keypoints, the visitors will remind (and understand) all these precautions better.
Just as they do in Pairi Daiza. I didn't encounter big problems there, thanks to the stewards and the visibile markings on the ground in the whole park. Or as they do in Monde Sauvage, with a very simple one-direction walkway and a lot of signs.
If you want to avoid any other people in a Zoo, the parks as Forestia or Caves of Han are maybe a good solution for you. Staying home forever isn't the solution if you want to stay healty. You also have to come out and enjoy!