Table 2.

Foci classification in Thailand

Foci classification	Current definition
A1	Active foci: village with indigenous cases in the current year
A2	Residual non-active foci: village without indigenous cases in the current year but with indigenous cases in the previous 3 years
B1	Cleared foci but receptive: village without indigenous cases for 3 consecutive years but vectors are found or environment is suitable for vector breeding
B2	Cleared foci but not receptive: village without indigenous cases for 3 consecutive but vectors are not found or environment is not suitable for vector breeding