An 11th case of typhoid has been confirmed in Auckland.
Auckland Regional Public Health Service clinical director Dr Julia Peters said that person had also been hospitalised.
All the cases were linked through a Pacific Island church community in Auckland, she said.
Auckland Regional Public Health Service was following up with 60 other contacts of the group.
"It is a localised outbreak," Peters said. "Knowing that the cases are connected gives us a clear direction but this is still a serious situation and we are following up other connections."
Auckland gets about 30 cases of typhoid a year but they are usually individual cases where someone has been infected overseas.
"This is a local outbreak and at this stage we do not know how or when it got into Auckland."
Peters said the public health service was trying to find the source but it was not always possible because some people can carry the disease for some time without passing it on.
Typhoid is spread primarily through food and water but could be spread person to person. Good basic hand-washing is one of the best means of protecting yourself.
Symptoms include a high fever developing over several days, headaches, general weakness and muscle aches. Stomach pain and constipation were also common but some people got diarrhoea.
Typhoid is a serious illness and is potentially fatal but can be treated with antibiotics.
Anyone with those symptoms should see their doctor or an after-hours clinic, or call Healthline on 0800 611 116.