Hepatitis A is principally transmitted by faecal and oral contact (through infected food or water), while sexual transmission is through anal-oral contact, such as rimming (licking the anus), fingering (stimulation of genitals and anus by fingers) and scat play (contact of oral mucous membrane with faeces). The period elapsing between infection and the first symptoms of the disease is 2 to 6 weeks. Half of infected persons do not experience any problems or have only mild symptoms without apparent jaundice (exhaustion, lack of appetite, stomach aches etc.). The symptoms that appear in the pre-jaundice period resemble those of influenza; they are followed by vomiting, tension under the right side of the ribcage, possibly diarrhoea etc. This is followed by jaundice, lasting from 1 to 3 weeks. Complications are rare. Immunisation is possible.