Influence of climate variations on the epidemiology of bluetongue in sheep in Mainland China

- Change trend of disease cases is associated with the meteorological factors.
- An adjusted Poisson model was used to assess impacts of climate variations.
- Temperature showed significantly positively effect on disease occurrences.
- Rainfall showed limited positively effect on the prevalence of the disease.
- Meteorological factors can be used to estimate disease occurrences in future.

In this paper, our aim is to clarify the effect of climate variations on the epidemiology of bluetongue in sheep in Mainland China based on data collected from 2006 to 2016. There are a total of thirty-one provinces in Mainland China, twenty-nine of them have reported the infections of BTV. We used univariate logistic regression analyses to control for the collinearity and applied a time-series adjusted Poisson regression model to assess the effect of climate variations on the prevalence of bluetongue. Our results suggest that a 1 °C rise in mean monthly minimum and maximum temperature will be related to a 3.4% and 10.7% increase in the monthly number of cases of BTV infections in sheep, respectively. What's more, rainfall also show a positively influence on the prevalence of bluetongue in sheep. These findings suggest that the risk of BTV infections in sheep increases in warm and humid environments. Moreover, meteorological variables may be used to predict possible outbreaks in this area and other regions characterized by similar climatic conditions.