Human normal immunoglobulin is derived from donations of pooled human plasma. It contains antibodies, mainly immunoglobulin G (IgG), to various bacteria and viruses present in the general population such as hepatitis A, measles, mumps, rubella and varicella. It has a distribution of IgG subclasses that is very close to that of the normal human plasma. It is therefore, used to provide passive immunisation against such diseases.