Rome, Italy · 15 February 2018 — By early 2018, the Fall Armyworm (Spodoptera frugiperda), a migratory and highly destructive insect pest native to the Americas, had established itself across nearly all of sub-Saharan Africa. First detected on the continent in early 2016, the pest spread with extraordinary speed, reaching over 40 countries within two years. The Food and Agriculture Organization (FAO) of the United Nations declared it a major threat to food security, estimating that it could cause annual maize losses of 8 to 16 million tonnes across Africa — a blow valued between USD 2.4 and 4.8 billion. In February 2018, the FAO launched a comprehensive guide for integrated pest management, signalling a strategic shift from attempted eradication to sustainable, long-term control.
An Invasive Pest on the Move
The Fall Armyworm is native to tropical and subtropical regions of the Americas, where it is a well-known agricultural pest. Its arrival in Africa was first confirmed in January 2016, when it was identified in maize fields in Nigeria and several West African countries. Genetic analysis suggested the pest had likely arrived via long-distance wind-assisted flight or through international trade. Once established, its biological characteristics made containment virtually impossible.
The adult moth can fly up to 100 kilometres in a single night, aided by wind currents. A single female can lay up to 1,000 eggs in her lifetime, and the larvae — the destructive stage — can feed on over 80 plant species, though maize is the preferred host. In the Americas, the pest is managed through a combination of genetically modified Bt crops, pesticides, and integrated pest management developed over decades. In Africa, where most maize is grown by smallholder farmers with limited access to inputs and extension services, the pest encountered a highly vulnerable agricultural landscape.
Why Maize Matters
Maize is the primary staple crop for over 300 million people in sub-Saharan Africa. It accounts for more than 30% of total caloric intake in several countries, including Zambia, Malawi, and Kenya. For millions of smallholder farmers, maize is both a food source and a cash crop, making the Fall Armyworm invasion a direct threat to both nutrition and livelihoods.
The pest's impact was particularly severe because it attacks the plant at its most vulnerable stage. The larvae burrow into the whorl — the growing point of the maize plant — where they are protected from pesticides and natural predators. By the time damage is visible, the crop has often already suffered significant yield loss. For farmers who depend on a single planting season, this can mean the difference between food security and hunger in the months ahead.
Country-Level Evidence
Reports from affected countries in 2017 and 2018 documented the scale of the damage. In the Democratic Republic of the Congo, a 2018 assessment estimated that Fall Armyworm was responsible for 45% of maize harvest losses, amounting to approximately 0.9 million tonnes in the 2017–2018 season alone. In Zambia, the government reported that over 130,000 hectares of maize were affected in the 2016–2017 growing season. In Ethiopia, surveys found the pest in nearly all maize-growing regions.
| Country | Reported Impact (2017–2018) |
|---|---|
| DR Congo | 45% maize harvest loss (0.9 million tonnes) |
| Zambia | 130,000+ hectares affected |
| Ethiopia | Pest detected in all maize-growing regions |
| Kenya | Yield losses reduced from ~20% to ~5% with intervention |
| Nigeria | Among first countries affected; widespread infestation |
FAO's Strategic Shift
By 2018, it was clear that eradication was no longer a feasible option. The pest was too widely established, too mobile, and too biologically adaptable to be eliminated from the African continent. The FAO's response evolved accordingly, shifting from emergency containment to sustainable management.
Integrated Pest Management Guide
In February 2018, the FAO launched a comprehensive guide titled Integrated Management of the Fall Armyworm on Maize, designed for use in Farmer Field Schools across Africa. The guide provided farmers with practical, ecological management strategies, including:
- Regular monitoring and scouting of maize fields for early detection of egg masses and larvae
- Biological control using natural enemies such as Telenomus remus, a parasitic wasp that targets Fall Armyworm eggs
- Botanical pesticides derived from neem and other locally available plants
- Intercropping and push-pull strategies that disrupt the pest's ability to locate and colonise maize plants
- Conservation agriculture practices that improve soil health and plant vigour, making crops more resilient to pest damage
The guide was part of a broader framework that the FAO had been developing since 2016, including the "Framework for Partnership for Sustainable Management of the Fall Armyworm in Africa," which guided national and regional interventions.
Country-Level Support
By late 2018, the FAO had over 20 projects operational across Africa, focusing on surveillance, early warning systems, and training extension workers. In Kenya, where the government and partners had invested in farmer sensitisation campaigns, maize yield loss levels dropped from approximately 20% in 2017 to around 5% in 2018 — a reduction attributed to timely intervention and favourable weather conditions.
The Path to a Global Action
The groundwork laid in 2018 fed directly into the more formal Global Action for Fall Armyworm Control, which the FAO launched in 2019. The Global Action aimed to coordinate management efforts across Africa, Asia, and the Near East — regions where the pest had spread or was expected to spread — and to mobilise resources for surveillance, capacity building, and research.
The Fall Armyworm's arrival in Asia was confirmed in 2018, when the pest was detected in India, and it subsequently spread to China, Southeast Asia, and Australia. By 2020, it had been reported in over 100 countries, making it one of the most rapidly spreading agricultural pests in recorded history.
Implications for African Agriculture
The Fall Armyworm invasion highlighted several structural weaknesses in African agricultural systems:
- Weak biosecurity and quarantine systems — the pest's initial arrival went undetected for weeks or months, allowing it to establish before any response was mounted
- Limited extension services — many smallholder farmers lacked the information and resources to identify and manage the pest effectively
- Dependence on a narrow range of staple crops — the heavy reliance on maize across the continent amplified the impact of a maize-specific pest
- Inadequate early warning systems — the speed of the pest's spread outpaced the capacity of national plant protection organisations to track and respond
These lessons informed subsequent policy discussions, including calls for greater investment in plant health infrastructure, crop diversification, and the development of pest-resistant crop varieties suited to African growing conditions. Several African research institutions, including the International Centre of Insect Physiology and Ecology (icipe) in Kenya and the International Institute of Tropical Agriculture (IITA) in Nigeria, intensified research on biological control agents and host-plant resistance.
The experience of 2018 also reinforced a truth that agricultural scientists had long emphasised: that pest management in smallholder farming systems must be built on ecological principles and farmer knowledge, not on a reliance on chemical inputs that are often unaffordable, environmentally damaging, and prone to resistance development. The Farmer Field School approach — pioneered in Asia in the 1980s for rice IPM — proved adaptable to the African maize context, offering a model for building farmer capacity that extends well beyond any single pest.
Sources:
- FAO, Integrated Management of the Fall Armyworm on Maize: A Guide for Farmer Field Schools in Africa (February 2018)
- FAO, Fall Armyworm Brief (January 2018)
- International Plant Protection Convention (IPPC), "Fall Armyworm: An Emerging Food Security Global Threat" (2018)
- CABI, Fall Armyworm Evidence Note (October 2018)
- FAO, Global Action for Fall Armyworm Control (2019)
- Food Tank, "Fall Armyworm Threatens Africa Food Security" (February 2018)
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Institutional Research Desk · Foresight Institute of Research and Translation
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