Recent faked evidence from Most Haunted Live in 2015 from the:
Poltergeist House, 30 East Drive Pontefract.
Spiritual attachents and possessions are all flavour of the same thing.
These non-crossed over spirits human or not, who have attached themselves to your energy field for the purpose of using your energy and or manipulating your your behaviour to serve themselves.
Some spirit attachments can actually be friendly, lost individuals who have inadvertently attached themselves as a means to get energy, not realising it is actually harmful, but others can attach maliciosly and intentionally harmful.
Signs of Spiritual Attachment:
1) Lethargy and feeling of exhaustion. (During an investigation)
2) Chronic Illness. ( During or after an investigation)
3) Sudden onset of irritability, crankiness or snappiness. (During an investigation)
4) Anger or Rage, issues not previously present. (During an investigation)
5) Alcohol or Drug dependence. (After an investigation)
6) Certain mental conditions like schizophrenia. (After an investigation)
7) Frequent nausea or stomach illness. (During or after an investigation)
8) Feeling like your house is haunted. (After an investigation)
9) Extreme and often dangerous mood fluctuations. (During or after an ivestigation
10) Sudden behaviourial or peronality change. (During an investigation)
11) Feeling like you are dragging or being weighed down all the time. (During or after an investigation)
12) Feeling a heaviness or pressure. (During or after an investigation)
13) Developing new vices. (After an investigation)
14) Having a negative outlook on life. (After an investigation)
15) Finding yourself saying gruesome or morbid things. (During or after an investigation)
16) Horrifying dreams. (After an investigation)
17) Someone else points out to you any of the signs listed above, or from more poignant or multiple people. (During or after an investigation)
This list is not definitive list, and spiritual possession can affect you in many ways, so keep an eye on fellow investigators at locations, if you or a fellow investigator are subject to an attachment, you can ask for the spirit to remove themselves from the person affected or take the person out of the environment/room or location and allow the person to recover before proceeding.
Many paranormal groups/investigators say a protection prayer before starting the investigation, and a closing prayer at the end of the investigation to help guard against and prevent possesion or attachment during and after an investigation.