The number of paratyphoid fever cases in Hawke's Bay continues to rise, with six patients now requiring hospital treatment.
Since Friday three more cases of the typhoid-like fever have been confirmed by the Hawke's Bay District Health Board. All patients had required hospital care at Hawke's Bay Hospital, with one person needing treatment in Auckland. All six were recovering.
At least three of the patients had eaten mussels gathered from Napier's Ahuriri area.
Local hapu leaders had planned to put out a rahui over the area, but decided not to as there were already signs in place.
A rahui is a form of tapu restricting access to, or use of an area or resource by unauthorised persons.
A Ngati Kahungunu Iwi Inc spokeswoman said the iwi were concerned about the whanau who had been affected by the fever and for those who could become affected if they weren't aware of the illness.
There was also concern mussels from the same area may have been eaten at a tangi at Tangoio Marae nearly a fortnight ago.
This was the tangi for former Hastings resident Vincent Taurima, who was one of two men found in Tongariro National Park after an extensive four-week search by police.
The HBDHB is continuing to investigate other cases.
Medical Officer of Health Nick Jones said paratyphoid fever was a serious illness and a notifiable disease.
"It's very important people heed the warnings and don't eat shellfish gathered from the Napier Marina area."
People with the disease will have a fever, chills, headache, possibly a rash and may also get severe vomiting and diarrhoea.
It generally occurs within 10 days of consuming contaminated food or water but symptoms may take as long as four weeks to develop.
The HBDHB has teams in the community working to follow up with anyone that was sick, but said the most important thing for sick people was to get medical help.
"People with paratyphoid can carry the bacteria in their blood and in their stomach and gut so it is possible for it to be passed on through faeces," Dr Jones said.
"Hand washing is extremely important to help prevent infecting other people as you can get paratyphoid if you eat or drink things that have been handled by a person who has the bacteria".
Anyone feeling sick and who has eaten shellfish from the Napier Marina area should contact their family doctor or they could call HealthLine 24/7 0800 611 116.
- More information on how to protect yourself and others is available from ourhealthhb.nz