Global chocolate supply under threat from virus, study finds

A cocoa plant eating bug poses a “real threat” to the global supply of chocolate, scientists have warned.

The price of cocoa beans is set to soar in 2024 as supply runs low. Picture: Education Images/Universal Images Group via Getty Images

The world’s chocolate supply is being threatened by a highly destructive virus wreaking havoc on cacao trees in West Africa, scientists have found.

Cocoa swollen shoot virus disease is among the most economically damaging diseases of cacao trees and accounts for almost 15-50 per cent of harvest losses in Ghana – the world’s second largest producer of the crop after the Ivory Coast.

This virus is transmitted by several species of mealybugs (Pseudococcidae, Homoptera) when they feed on cacao plants. They eat the leaves, buds and flowers of trees.

“This virus is a real threat to the global supply of chocolate,” said Benito Chen-Charpentier, a professor of mathematics at the University of Texas at Arlington, who authored a new study published in the journal PLOS One.

Scientists have attributed the rise in the disease to “globalisation, climate change, agricultural intensification and reduced resilience in production system”.

Cocoa beans dry on a table in a village outside of Kumasi, Ghana. Picture: Bloomberg via Getty Images

Prof Chen-Charpentier said pesticides don’t work well against mealybugs, leaving farmers to try to prevent the spread of the disease by cutting out infected trees and breeding resistant trees.

He added: “Ghana has lost more than 254 million cacao trees in recent years”.

Farmers can combat the mealybugs by giving vaccines to the trees to inoculate them from the virus. But the vaccines are expensive, especially for low-wage farmers, and vaccinated trees produce a smaller harvest of cacao, compounding the devastation of the virus, the study cites.

Prof Chen-Carpentier and his colleagues have come up with a possible solution but it’s still in the early stages.

They use mathematical data to determine how far apart farmers can plant vaccinated trees to prevent mealybugs from jumping from one tree to another and spreading the virus.

“Mealybugs have several ways of movement, including moving from canopy to canopy, being carried by ants or blown by the wind,” Prof Chen-Charpentier said.

Local farmers gather dried cocoa beans to be weighed before selling them to merchants in a village outside of Kumasi, Ghana. Picture: Bloomberg via Getty Images

“What we needed to do was create a model for cacao growers so they could know how far away they could safely plant vaccinated trees from unvaccinated trees in order to prevent the spread of the virus while keeping costs manageable for these small farmers.”

Cocoa prices are tipped to soar to record highs this year amid an acute lack of cocoa beans from West Africa.

“NY cocoa is trading up 200 per cent year-on-year, while the London-based cocoa future has rallied even stronger, with the May 2024 futures contract up 105 per cent year to date,” Saxo Head of Commodity Strategy Ole Sloth Hansen told NewsWire last month.

“While the poor harvest in West Africa remains the focus, fears have also risen in Europe that incoming European Union regulations – which are aimed at preventing the retailing of products that destroy forests – will make it even harder for top European chocolate makers to secure supplies.”

Two global confectionery companies, Hershey and Cadbury, have in recent months noted that price hikes for consumers are possible as the cocoa-supply shortages continue.

Originally published as Global chocolate supply under threat from virus, study finds