Climate shocks, crop losses and health risks in Africa ^{CEFR B2}

Climate shocks across Africa are shifting ecosystems, increasing crop failures and opening new pathways for disease. In Bazua, in Ghana's Upper East region, farmer Martin Ariku says that after more than 20 years of supplying improved seeds to smallholders he faced an unusually destructive season. Drought arrived early, followed by intense short rainstorms that drowned plants. Yields fell to as low as five 100-kilogram bags per acre for maize, rice, cowpea, soybean and sorghum, compared with the usual 15, and even a sorghum variety introduced by SNV Ghana failed to survive the rapid swings.

A CABI survey found 98 per cent of farmers questioned in Ghana and Zambia reported maize infection, with average losses of 26.6 per cent in Ghana and 35 per cent in Zambia. CABI estimates US$177 million of maize are lost each year in Ghana and US$159 million in Zambia. Scientists warn that higher temperatures speed pests' metabolism and reproduction, allowing species such as Fall Armyworm to expand their range; Copperfield Banini of Ghana's Ministry of Food and Agriculture says warming conditions fuel these populations.

These agricultural shocks are linked to public-health problems. Reduced food and income increase malnutrition and weaken immunity. Shauna Richards at the International Livestock Research Institute explains that new pools of stagnant water after heavy rains create breeding grounds for mosquitoes, and floods can mix sewage with drinking water, raising the risk of cholera. Denser vegetation in wetter areas also creates habitats for disease-carrying insects. Rift Valley fever outbreaks in East Africa have followed heavy rainfall and flooding, showing how zoonotic spillover can rise with climate change; the One Health Horizon Scanning research highlights these interconnected risks.

Local reports describe hotter nights and more frequent malaria, and Patience Kiyuka says Anopheles stephensi has appeared in cities such as Nairobi, threatening urban malaria control and prompting a rethink of bed-nets and indoor spraying. Public-health physician Ama Essel warns that many clinics lack strong buildings, reliable electricity and vaccine cold chains. She calls for stronger infrastructure, vaccine investment and better transport and energy systems, and says sufficient funding is needed as the climate crisis advances.