Table 4.

Factors associated with number of Culex mosquito vectors for Japanese encephalitis virus collected at households keeping pigs in Ninh Kieu, Can Tho City, Vietnam*

Risk factor	No. mosquitoes	Cx. vishnui subgroup	Cx. tritaeniorhynchus	Cx. gelidus	Cx. quinquefasciatus	Culex males	Proportion of blood-filled mosquitoes
Catch near pigs	3.89†	7.77†	8.96†	17.1†
No. pigs in household	1.04‡	1.05§	1.05§
Pig density in ward				1.03§
Rice field or fish pond				−118
Rice fields and fish ponds in ward
Other livestock in household				32,779‡
Large ruminant density in ward				−1.86§
No. persons in household	1.25§			1.53‡
Population density in ward
Pets in household

^*Change in number of mosquitoes is the anti-logarithm of the coefficient β.

^†P < 0.001.

^‡P < 0.01.

^§P < 0.05.