Table 2. Correlation coefficients between climatic, environmental factors and the numbers of reported cases in Huaiyuan and Jingde counties, Anhui Province, China, 2004–2023.

Characteristics	Lag (months)
	0	1	2	3	4	5	6
Abbreviation: NDVI=normalized difference vegetation index. * P<0.050 ** P<0.001.
Huaiyuan
Average temperature (℃)	0.340**	0.439**	0.374**	0.223**	0.056	−0.096	−0.266**
Rainfall (mm)	0.279**	0.389**	0.339**	0.182**	0.038	−0.05	−0.147*
NDVI	0.377**	0.342**	0.116	0.108	0.208**	0.155*	−0.029
Maximum temperature (℃)	0.336**	0.437**	0.375**	0.224**	0.056	−0.094	−0.269**
Minimum temperature (℃)	0.340**	0.441**	0.375**	0.229**	0.065	−0.096	−0.264**
Jingde
Average temperature (℃)	0.232**	0.410**	0.431**	0.293**	0.122	−0.063	−0.236**
Rainfall (mm)	−0.027	0.190**	0.272**	0.343**	0.234**	0.113	0.018
NDVI	0.248**	0.394**	0.398**	0.246**	0.048	−0.178**	−0.178**
Maximum temperature (℃)	0.243**	0.411**	0.430**	0.284**	0.123	−0.054	−0.230**
Minimum temperature (℃)	0.220**	0.409**	0.435**	0.304**	0.120	−0.072	−0.239**