The Ministry of Health has confirmed nine New Zealanders have had the Zika virus after visiting the South Pacific this year.

READ MORE: Zika virus could affect millions

A 47-year-old Waikato man is in a stable condition in Waikato Hospital with symptoms of Guillain-Barre.

The condition is linked to the Zika virus and can cause paralysis, but most most patients make a full recovery from the disease.

The other eight individuals have fully recovered.

Chief medical officer Dr Don Mackie said the notifications should be seen in the context of a large number of travellers in the region.

He says there were 57 Zika notifications in 2014, and six last year.

The Ministry has also extended its travel warning to Tonga - which along with Samoa, has been found to have the virus.