Table 3.

Correlation between ENSO indicators and the occurrence of dengue epidemics over time lags from 1 to 12 months - local climate parameters are also shown for comparison.

Region/Time-lag (month)	ENSO indices		Local climate parameters
	MEI	SLP	Tmax	Tmean	Tmin	Rh	WDSP
In the five southern coastal provinces
Lag 1	0.51*	-0.14*	0.28*	0.46*	0.47*	NS	NS
Lag 2	0.60*	-0.15*	0.27*	0.44*	0.35*	NS	NS
Lag 3	0.66*	-0.24*	0.35*	0.45*	0.19*	-0.05*	NS
Lag 4	0.68*	-0.22*	0.35*	0.43*	0.16*	-0.07*	NS
Lag 5	0.66*	-0.26*	0.30*	0.32*	NS	-0.07*	NS
Lag 6	0.59*	-0.26*	0.26*	0.25*	NS	-0.07*	NS
Lag 7	0.50*	-0.28*	0.16*	0.19*	NS	NS	NS
Lag 8	0.42*	-0.24*	NS	NS	NS	NS	NS
Lag 9	0.39*	-0.20*	NS	NS	NS	NS	NS
Lag 10	0.36*	-0.17*	NS	NS	NS	NS	NS
Lag 11	0.28*	-0.15*	-0.19*	-0.24*	NS	NS	NS
Lag 12	NS	NS	-0.17*	-0.26*	NS	0.07*	NS
In the eight northern mountainous provinces
Lag 1	1.31*	-0.37*	0.19*	0.25*	0.30*	-0.04*	NS
Lag 2	1.29*	-0.38*	0.23*	0.27*	0.20*	-0.07*	NS
Lag 3	1.26*	-0.39*	0.26*	0.25*	0.12*	-0.09*	NS
Lag 4	1.28*	-0.36*	0.15*	0.09*	NS	-0.06*	NS
Lag 5	1.15*	-0.40*	NS	NS	NS	NS	NS
Lag 6	0.91*	-0.36*	NS	NS	NS	NS	NS
Lag 7	0.85*	-0.27*	NS	NS	NS	NS	NS
Lag 8	0.84*	-0.30*	0.09*	NS	NS	NS	NS
Lag 9	0.88*	-0.23*	NS	NS	NS	NS	NS
Lag 10	0.93*	-0.35*	NS	NS	NS	NS	NS
Lag 11	0.84*	-0.41*	NS	NS	NS	NS	NS
Lag 12	0.60*	-0.37*	NS	NS	NS	NS	NS

NOTE. Data shown are the logistic regression coefficient of a lagged variable after adjusting for effects of seasonality, population density, and province.

*Statistically significant; NS, not significant.

Abbreviations: MEI, Multivariate ENSO index (monthly average); SLP, sea level pressure index (monthly average); Tmax, maximum daily temperature (monthly average); Tmin, minimum daily temperature (monthly average); Tmean, mean daily temperature (monthly average); Rh, relative humidity (monthly average); WDSP, wind speed (monthly average).