But is this the only one?

Yes There is only one vaccine manufacturer in China, and there are no competing products, which is not affected by the purchase of quantity. It is an oral capsule vaccine, inactivated and widely used by people, so it is exclusive. Shanghai United Searle Bioengineering Co., Ltd. is the industrial base of OraVacs under United Pharmaceutical Group, which integrates the manufacture, sales, development and research of genetically recombinant biological products.