About 90 staff and students at a school where measles has been identified do not have adequate proof of immunity to the virulent and dangerous disease, and a chemist has been listed as a possible exposure point.

Last week an Albany Senior High School student tested positive for the virus prompting the school to close.

So far, there are just two positive cases, a student and one of their household contacts who likely infected the student and who had recently travelled overseas.

Nevertheless, the school had announced classes would be held online today while authorities worked to contain any possible links to the disease.

Public health officials were working out who among the school’s 1000 staff and students might not be vaccinated or immune to the disease.

Auckland Regional Public Health Service said there were about 75 students and 14 staff who might not be fully protected.

The agency had arranged for those people to be tested, had contacted them to ask that they isolate, and planned to check with them regularly about whether they had any measles symptoms.

The Ministry of Health had also listed a possible measles exposure event in Auckland on its website.

It said the risk was low, but that anyone who was at Chemist Warehouse in Albany on Thursday 20 April, between 2.45pm and 4.30pm and who was not immune should be watchful for symptoms. (Details about who was and was not considered immune were listed on the website).

Measles is a highly contagious viral disease that can be fatal and cause long-term damage, but is “easily preventable with immunisation” the Ministry of Health website said.

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Symptoms develop between seven and 13 days after exposure and include fever, cough, runny nose, sore and watery ‘pink’ eyes, and later a blotchy rash.

Anyone who thought they could have measles should call Healthline on 0800 611 116 or ring their GP, the ministry said. But because of how transmissible the disease is, they were asked not to visit their doctor without calling first.

Pop up vaccination clinics were held in Auckland during the weekend.

-RNZ