Positive association between ambient temperature and salmonellosis notifications in New Zealand, 1965-2006

To investigate the temporal relationship between the monthly count of salmonellosis notifications and the monthly average temperature in New Zealand during the period 1965-2006.

A negative binomial regression model was used to analyse monthly average ambient temperature and salmonellosis notifications in New Zealand between 1965 and 2006.

A 1°C increase in monthly average ambient temperature was associated with a 15% increase in salmonellosis notifications within the same month (IRR 1.15; 95% CI 1.07 - 1.24).

The positive association found in this study between temperature and salmonellosis notifications in New Zealand is consistent with the results of studies conducted in other countries. New Zealand is projected to experience an increase in temperature due to climate change. Therefore, all other things being equal, climate change could increase salmonellosis notifications in New Zealand.

This association between temperature and salmonellosis should be considered when developing public health plans and climate change adaptation policies. Strategically, existing food safety programs to prevent salmonellosis could be intensified during warmer periods. As the association was strongest within the same month, focusing on improving food handling and storage during this time period may assist in climate change adaptation in New Zealand.