Population risk factors for measles in New Zealand
Despite eliminating endemic measles in New Zealand, small outbreaks continue to occur, with recorded cases in Auckland , Palmerston North and Waikato within the last 12 months alone.
Since measles outbreaks over the last decade in New Zealand occur as introductions from abroad, IDReC researchers David Hayman, Jonathan Marshall, Nigel French, Tim Carpenter and Mick Roberts assess the current risk factors in a recent paper in Epidemiology and Infection. Using a generalized linear model the authors analyse risk factors for 1137 measles cases from 2007 to June 2014, provide estimates of national immunity levels, and model measles importation risk.
The results suggest that overseas visitors and/or returning NZ travellers are seeding measles outbreaks and that this risk is highest at peak visitation time during December. They also caution that current immunization levels in New Zealand are insufficient to prevent future outbreaks because of heterogeneous immunity in the population, leaving particular age groups at risk.
Read the full publication here