Eradication of Frankliniella occidentalis and tomato spotted wilt virus in Finland: a case study on costs and benefits

Western flower thrips ( Frankliniella occidentalis ) invaded Finland in 1987/1988. In the following year, tomato spotted wilt virus (TSWV) was identified in vegetable and ornamental crops. An eradication campaign was initiated in autumn 1987. Growers were ordered to take measures against F. occidentalis and TSWV and were advised how to avoid these new pests; the import regulations were amended to intensify pre-export and pre-entry control; a research programme was started to develop biological control of F. occidentalis. At present, F. occidentalis occurs only sporadically in a few places and is not a problem for the growers. TSWV has not been identified since 1989. Eradication measures cost the government FIM 1.6 million in 1987/1990. The financial cost of eradication to the industry has been impossible to assess. It has been calculated that 'living with' F. occidentalis and TSWV cost at least FIM 35 million over a period of 4 years. The cost/benefit ratio is thus about 1:20. The eradication campaign has therefore been highly profitable.