Measles linked to Auckland strain
Hamilton's measles outbreak has been linked with the same strain that plagued Auckland earlier this year.
Waikato Population Health Service confirmed the strains were both connected but could not confirm how it spread to Hamilton.
Medical officer of health Dr Anita Bell said 95 cases had been confirmed in the Waikato since the outbreak began in June.
The outbreak began among students at Fraser High School in Hamilton and spread to four other schools, including one in Raglan.
Bell said the source could have been contact with an Auckland case or importation by foreign travel.
She would confirm any new cases today.
"The number of cases in the community are directly related to the proportion of the population who get vaccinated to stop the spread of the disease. It tends to blow itself out and then, if someone comes in from overseas with measles, it can take off again."
Attempts to eradicate the virus in New Zealand began in 1969 when a universal vaccine was introduced but vulnerability remains high among unimmunised communities.
New Zealand considers itself to be largely measles free, meaning that most outbreaks require a person to bring the virus in from overseas, before exposing unimmunised New Zealanders.
Information provided by New Zealand's Immunisation Advisory Centre states that prior to the vaccine most people contracted measles before the age of 20.
"The last two major epidemics in New Zealand occurred in the 1990s with thousands of cases, hundreds of hospitalisations and seven deaths," the report said.
NorthCare Medical Centre in Hamilton reported up to 70 people a day were lining up for their Measles-Mumps-Rubella jab since the outbreak began.
Of the city's 95 cases, 48 were laboratory-confirmed, while the rest were people close to someone with a confirmed case who had a "clinically compatible illness".
Almost a quarter of confirmed cases were people who lived with someone with measles and had been placed in quarantine before they were unwell.
Younger people and those who had not received two doses of MMR were still most at risk.
Measles is a highly infectious viral disease spread from person to person through the air by breathing, sneezing or coughing. It can lead to serious complications such as permanent hearing loss, brain damage, or even death.