The outbreak occurred after the vessel took on fresh food supplies in Cape Town, South Africa, in early April. The AIMPE's application states that shigella, a highly contagious bacterial gastroenteritis also known as bacillary dysentery, spread through the vessel following the contaminated food.
Nathan Niven from the AIMPE, who is representing crew members but was not on the vessel, described the experience as "like seasick times 10, which is very unpleasant." Symptoms of shigella include diarrhoea (often with blood and mucus), fever, nausea, vomiting and abdominal pain. The Australian Centre for Disease Control notes it usually lasts four to seven days and can cause complications including dehydration, sepsis, severe inflammation of the colon and reactive arthritis.
By the time the ship reached Mauritius, "the majority of the crew" had fallen ill, Mr Niven said. One crew member was hospitalised for several days in Mauritius, and another received hospital treatment in Australia. With multiple crew members bedridden, including four of the six engineers, the ship was forced to continue towards Fremantle with limited staff. The application states that between 8 April and 17 April, only one fit engineer was available to maintain watches at a time instead of two.
The delivery voyage began in early March and was seen as a positive turning point for Tasmania's much-maligned ferry replacement program, which has been millions of dollars over budget and years behind schedule.