Another person has been hospitalised in Auckland's typhoid outbreak.
A file photo of Auckland City Hospital: It is unclear which hospitals have treated the 11 people. Photo: RNZ / Bradley Ambrose
Auckland Regional Public Health Service (ARPHS) said an 11th confirmed case had been identified and the person was in hospital.
All cases are linked and are among members of a Pacific church community in Auckland, said Dr Julia Peters, the regional health service's clinical director.
Health officials first issued an alert on Friday saying 10 people were in hospital.
Auckland gets around 30 cases of typhoid a year but are usually individual cases where someone has been infected overseas.
So far the source of the latest case has not been indentified.
The service was following up with 60 contacts of the church group, Dr Peters said.
"It is a localised outbreak. 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.
"At this stage we do not know how or when it got into Auckland."
Symptoms include a high fever developing over several days, headaches, general weakness and muscle aches. Stomach pain and constipation are also common but some people get diarrhoea.
Typhoid is a serious illness, and is potentially fatal, but can be treated with antibiotics.