text: Depends on what type of serology you are talking about but here is a few:\n *   detects exposure but not when exposure occurred. Difficult to distinguish between antibodies due to vaccination and due to disease.\n    * to get meaningful information -\n          o paired sets of sera (acute and convalescent samples) - takes time but useful for management decisions\n          o IgM - shows recent exposure, for viruses with transient IgM response\n          o antibodies in CSF for CNS infections - vaccines do not usually produce antibodies in CSF