If somebody is on an anti-TNF inhibitor, should they avoid coming into contact with somebody who has had chickenpox and what about flying is it ok to stay on these drugs when going on holiday?
If a person has never had chicken pox and is taking a TNF inhibitor, he/she should avoid contact with a person who does have chicken pox. As for traveling, it is okay to travel and continue taking the TNF inhibitor (be sure you keep it cold at all times). The airline may require a note from the treating doctor, so it is best to be prepared with this. For folks traveling to areas where tuberculosis is rampant (like working with poor populations in India or Brazil or Nigeria, etc), then stopping the TNF inhibitor during that time would probably be wisest.