The outbreak of hepatitis A affecting nine Auckland schools is now under control, but the kids in the affected zones are not yet entirely safe, according to the region's public health service.

As of Monday, 30 cases of Hepatitis A - probable and confirmed - had been reported, but there have been no new ones since last Wednesday.

Most of those affected are reportedly primary and secondary school-aged children.

"It really is important to stress to parents that they don't have to be concerned in general, because the risk is assessed as being low," Medical officer of health Shanika Perera told the Herald a week ago.

Hepatitis A is a liver disease caused by a virus that thrives in faecal contamination. It is transmitted from person to person via food or drink. The best protection against it is careful washing and drying of hands after going to the toilet and before eating, the New Zealand Herald reports.

Symptoms of Hepatitis A include vomiting, diarrhea, mild fever and jaundice or the yellowing of the skin and the eyes. Infected adults can be sick for months, but is usually milder in children, the Herald notes.

Hepa-A vaccine is available for parents who want to make sure their children are safe against the disease that could get far worse than it naturally gets, if not properly managed.