Typhoid is an infection caused by the bacterium, salmonella typhi and salmonella paratyphi. The infection causes inflammation of the liver, headache, fever, confusion and abdominal pain. It can be fatal if medical attention is not sought immediately. Typhoid is highly contagious and is transmitted through infected water which has been contaminated by faeces or eating infected foods. It is also passed through flies that have had contact with human faeces, which then go on to contaminate food.