Estimated costs of plum pox virus and management of sharka, the disease it causes

Abstract

The disease “sharka”, caused by Potyvirus plumpoxi (plum pox virus), is the most harmful viral disease affecting stone fruits. The virus spreads over long distances through illegal and insufficiently controlled exchange of infected propagative plant material. Once established in an area, the virus spreads locally through vegetative propagation of infected plant material, and naturally through aphid-vectors. Previously considered a European problem, sharka has now been reported in 54 Prunus-growing countries in all continents except Oceania, although the disease has been eradicated from the United States of America. The economic cost of the disease in the 28 years from 1995 to 2023 is estimated to be €2.4 × 10⁹, equivalent to approx. 0.17% of the stone fruit industry’s value. This includes more than over €2 × 10⁹ in direct fruit losses, €1.4 million from international rejection of symptomatic fruit, and over €100 million in eradication and disease limitation costs. Indirect costs include €137 million, mainly associated with ELISA analyses, and approx. €130 million in costs related to research and science networks. Cumulative global losses from the sharka pandemic since the decade 1910/20 probably surpass €13 × 10⁹. These outlays exclude indirect trade costs, economic losses, genetic erosion of traditional cultivars, and the costs of developing new cultivars tolerant or resistant to plum pox virus. The decline in these costs compared to the previously evaluated €10 billion from the 1970s to 2006 is analyzed. Four case studies (for Spain, Turkey, Chile, and Greece) illustrate different sharka scenarios and management strategies.