Tetanus skin test positive. What's going on?

A positive tetanus skin test refers to the antitoxin of tetanus. This antitoxin is not derived from human blood. Although it is an immunoglobulin, it is an immunoglobulin obtained after immunization of horses. A skin test is required before injection into the human body because it may cause allergic reactions. If the immunoglobulin is from a human, it will not show a positive skin test. Therefore, to prevent tetanus, there are two drugs to choose from, one is derived from horse immunoglobulin, also known as tetanus antitoxin; the other is derived from human blood immunoglobulin, do not need to do skin test in advance. If tetanus antitoxin skin test positive, then you can choose desensitization injection, or you can choose directly from human immunoglobulin, but from human immunoglobulin costs more expensive.