A woman from Mangawhai with life-threatening dehydration, was shocked to find she had the Victorian-era disease, cholera

Health officials don't know how she came to be infected - but say there is no public health risk.

She's been treated with a specific antibiotic and put into isolation during treatment.

The Northland woman was so sick from diarrhoea, she collapsed in the shower.

Blood tests showed her kidneys were shutting down from dehydration.

Medical Officer of Health, Doctor Felicity Williamson, says only two strains of cholera are toxigenic, with the potential to cause an outbreak.