"This review identified another probable death where a man in his mid-80s died some time after the outbreak.
"While the man had tested negative for campylobacter infection at the time, on review it was decided that the test may have been a false negative, and could not exclude the possibility of campylobacter.
"On balance, it was decided it may have been a contributing factor."
The man's daughter, who did not wish to be identified, said her father was a "fit and healthy" 82-year-old living in Havelock North before the outbreak.
She said he was admitted to hospital at noon on the day the first notices started going out to the community warning of the contamination.
He was one of two people that were in intensive care in the days after the outbreak and she said it was time that his death and its link to the outbreak were acknowledged.
In its Stage 2 report, the inquiry said the potential for contamination of drinking water to cause widespread illness and, potentially, deaths was clearly seen from the outbreak.
"With only slightly different circumstances and/or a different pathogen, the outcomes of this outbreak could have been substantially worse."
When looking at the costs of the outbreak, the inquiry noted not all could be measured in economic terms.
"The value of human life, pain and suffering, or the benefits of ensuring New Zealand is a place where there is equal access to safe drinking water [a necessity] cannot adequately be reflected in such economic analyses."
The report referred to Havelock North GP Dr Culham, whose practice served most of the village, and his recollections of the first Saturday of the outbreak, which he said in a submission to the inquiry "was the worst day I've ever had as a doctor".
"The nature of the disease is that it goes on – five days, seven days. People coped well for the first 48 hours but you can only do it for so long.
"We concentrated on those most at risk, the elderly, frail, those with other medical conditions and small children. It became apparent early that the elderly were really suffering and they were a big group of people who needed support".
Former Hastings mayor Lawrence Yule said he was not aware that a fourth death was confirmed to be linked to the outbreak, and that his position was no different to the others who died.
"As with the others, I empathise with the families, and have the greatest sympathy."
Hastings mayor Sandra Hazlehurst said they had been aware there could have been a fourth person die from illness linked to the outbreak, but it had not been confirmed at that time.
"Our love, thoughts and deepest sympathy goes out to the family," she said.
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