Future?

In 2080 AD, mankind experienced the Third World War. After the war, the world was short of resources, the ecosystem was severely damaged, and the air was infected with a strange virus. Humans and animals would mutate in less than a month after inhaling it. For this reason, humans specially built an ecological protection shield, which contained less than 1 million people. Its people all inhaled the polluted air and mutated it. All the animals on the earth died. The remaining 1 million people could only eat vegetarian food every day. I don't know when a factory suddenly appeared in this ecological protection shield and said that it had researched meat food. But all the animals died. Where did the meat come from? What is the ulterior secret behind this factory? This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.