Different responses of Japanese encephalitis to weather variables among eight climate subtypes in Gansu, China, 2005–2019

Table 2 Statistics of epidemic indices of JE in climate zones of Gansu, 2005–2019

Climate zone	Cases	Population	EW	TW	EV	IR	Frequency index (α)	Duration index (β)	Intensity index (γ)
BWk	8	51,455,688	8	783	8	0.016	0.010	1.000	0.002
BSk	66	100,848,086	66	783	63	0.065	0.084	1.048	0.001
Cwa	164	16,033,155	156	783	141	1.023	0.199	1.106	0.007
Cwb	455	28,135,369	403	783	348	1.617	0.515	1.158	0.005
Dwa	147	28,087,413	135	783	121	0.523	0.172	1.116	0.004
Dwb	674	146,717,627	615	783	549	0.459	0.785	1.120	0.001
Dwc	5	15,272,584	5	783	5	0.033	0.006	1.000	0.007
ET	0	2,675,168	0	783	0	0	0	–	–

BWk temperate arid, BSk temperate semi-arid, Cwa subtropical winter dry, Cwb temperate oceanic continental, Dwa and Dwb continental winter dry, Dwa was characterized by snow climate, dry winter, and hot summer, Dwb was characterized by snow climate, dry winter, and warm summer, Dwc subpolar winter dry, ET alpine climate, EW epidemic weeks, the total number of weeks in which one or more cases are notified, TW total weeks, means the total number of weeks during study period, EV epidemic waves are defined as the number of weeks when cases successively occur, IR incidence rate, the weekly incidence rate (cases per 100,000 population) during a JE epidemic period

ISSN: 1471-2334