Combatting COVID-19 and CSSVD: A Similar Approach?

Similarities between the two viruses have stimulated a call for a better understanding of the links between environmental and human health.

The United Nations General Assembly declared 2020 the International Year of Plant Health to raise global awareness about how protecting the health of plants can help end hunger, reduce poverty, protect the environment, and boost economic development.

Yet as the world prepared to celebrate plant health, the COVID-19 pandemic drew attention to human health.

Cocoa Swollen Shoot Virus Disease (CSSVD) and COVID-19 are both caused by viruses that have enormous socio-economic consequences, particularly, in West Africa. They will continue to plague our lives if lasting solutions are not found. Mastery of the biology and epidemiology of these two diseases remains insufficient. All sick people may or may not show symptoms. While people with weak immune systems are most at risk of succumbing to COVID-19; the disease is also taking a toll on young people for reasons that are not yet known.

“Following up on recommended barrier measures remains one of the best options today to prevent the spread of the disease,” said Samba Mamadou, director-general of Health of Côte d’Ivoire.

These measures, implemented to varying degrees in more than 180 countries fighting the epidemic, are almost everywhere complemented by reduced travel, screening, contact tracing, monitoring and treatment.

Like COVID-19, CSSVD devastates old and young cocoa trees with accentuated damage in fields weakened by the age of the orchard, insufficient mineral nutrition and inadequate phytosanitary maintenance.

“CSSVD represents one of the greatest threats to cocoa production in West Africa today,” said Koffi N’goran, deputy director-general of the Conseil du Café – Cacao.

Cocoa production sustains more than 14 million households in West Africa alone. The production of Côte d’Ivoire and Ghana accounted for 70% of the world’s cocoa supply estimated at USD 51 billion in 2019.

Thousands of hectares of cocoa fields are being devastated by the disease, creating despair among farmers. The situation is likely to lead to massive job losses and drastic income declines for several million-cocoa producing households as well as affect supply to cocoa consumers if concerted action is not taken to eradicate the disease. To date, there are no resistant varieties of cocoa trees and no curative product for CSSVD.

“We must continue the early detection of diseased plants, raise awareness of the diversification of cocoa landscapes and planting of barrier trees to contain CSSVD,” said Yte Wongbe, director-general of the National Center for Agronomic Research.

Research is gathering momentum to find ways to eradicate the disease. World Agroforestry (ICRAF) and its partners are contributing to a CSSVD eradication program. Collaborations have been established with national and international research centers — National Center for Agronomic Research in Côte d’Ivoire; Cocoa Research Institute of Ghana; Centre de coopération internationale en recherche agronomique pour le développement in France; SwissDeCode in Switzerland — universities — L’Université Félix Houphouët-Boigny, L’Université Jean Lorougnon Guédé and L’Université Peleforo Gon Coulibaly à Korhogo in Côte d’Ivoire; University of Arizona in the USA; University of West England and University of Reading in the United Kingdom; and the University of Queensland in Australia — and international institutions, such as the World Cocoa Foundation.

The major pillars of the work support a better characterization of CSSV strains and vectors, the development of cost-effective early detection tools that can be used in the field, the characterization of the disease epidemiology, the selection of cocoa companion trees that are non-hosts of CSSV, biological control and vector management, and breeding for resistant cocoa varieties. In parallel, ICRAF deploys models for rehabilitation of degraded orchards through the promotion of cocoa-based agroforestry.

What are the causes?

Human activities have altered the climate and natural ecosystems; there are fewer and fewer species of plants and animals and the natural balance between the different forms of life has been disrupted, encouraging the proliferation of new diseases. The health of our planet and its ecosystems has become the greatest challenge of the 21^st century.

CSSVD is transmitted from an infected cocoa tree to a healthy cocoa tree through mealybugs when they feed. It first appeared in Ghana in 1922. The first outbreaks in Côte d’Ivoire were reported in 1943. It was estimated that more than 200 million infected trees were destroyed in Ghana in ‘cut and replant’ campaigns to control the disease. In Côte d’Ivoire, CSSVD reappeared at epidemic scale in 2003. Currently, the disease has affected several cocoa-producing areas in Côte d’Ivoire and Ghana.

COVID-19 is historically known from poultry and believed to have been transmitted to humans through contact with infected animals. In less than 3 months, COVID-19 has resulted in hundreds of thousands of deaths, the loss of uncountable numbers of jobs and significant global socio-economic disruption. To date, there is no vaccine or antiviral drug against this disease.

CSSVD and COVID 19 have dramatically marked the international year of plant health at the global level and particularly in West Africa. These two diseases have negative effects on all segments of the population, regardless of social class as well as on the well-being, livelihood and economy of society as a whole. We can only overcome their challenges by helping each other. We should therefore dedicate this year 2020 to the health of our entire ecosystem: humans, flora and fauna. We must capitalize on energies and resources to strengthen the transdisciplinary research teams working on the diseases in order to turn these crises into an opportunity for the well-being of our populations and our environment. Let’s act now!

This blog was originally published by World Agroforestry (ICRAF).