Monthly distribution of autochthonous dengue cases, imported dengue cases, mosquito density, meteorological variation and time interval between onset and diagnosis from January 2001 to December 2013 in Zhongshan, China. Mean rainfall (mm), monthly mean rainfall; mean temperature (°C), monthly mean temperature; MaxDTR (°C), monthly maximum diurnal temperature range; MTIOD (days), monthly median time interval between symptom onset and diagnosis by day; MeanBI, monthly mean Breteau Index; MinRH (%), monthly minimum relative humidity.