By Idowu Adewumi
What if the next Lassa fever outbreak is already unfolding quietly within our communities before symptoms even appear? Across Nigeria, renewed reports of suspected and confirmed cases—and continuing deaths that sometimes include frontline health workers—have heightened public concern.
These outbreaks are no longer rare emergencies; they are becoming predictable seasonal events. Beyond illness, Lassa fever disrupts household income, increases healthcare costs, and places sustained pressure on an already stretched health system. The consequences extend into productivity, food security, and community stability, making the disease as much a development issue as a medical one. Persistent environmental exposure, delayed care-seeking, and weak risk awareness continue to fuel transmission despite response efforts. Lassa fever is no longer a distant rural disease.
Recent analyses of surveillance data reinforce this concern.
Transmission in Nigeria has remained persistent, with recurring seasonal surges and enduring hotspots such as Ondo State. Between 2020 and 2024, case counts have fluctuated but remained sustained, with confirmed infections in Ondo peaking at 433 in 2023 and staying high through 2024, even as deaths declined from 83 in 2020 to 27 in 2024, suggesting some improvement in detection and case management.
Signals in early 2025 again showed rising suspected and confirmed cases and infections among healthcare workers, highlighting continued occupational risk. Current public health updates in 2026 also point to renewed activity across multiple states early in the year, reinforcing a troubling pattern: Nigeria’s Lassa fever outbreaks are seasonal, predictable, and not yet sustainably controlled. In simple terms, response capacity has improved, but transmission has not been fully interrupted.
Understanding why Lassa fever persists requires looking beyond hospitals. Transmission is sustained at the intersection of human behaviour, environmental conditions, and weak community-level detection.
The virus is carried by Mastomys rodents that thrive where poor waste disposal, overcrowded housing, and unsafe food storage create ideal breeding conditions. In many communities, delayed care-seeking and reliance on self-medication allow infections to worsen before they are detected. Under-reporting and weak grassroots surveillance mean early warning signals are often missed until clusters expand. Treatment costs and limited access to diagnostics further discourage timely presentation.
These realities show that Lassa fever is not only a medical problem but also an environmental and social one. In simple terms, the One Health perspective—recognising the link between human health, animal reservoirs, and the environment—offers the most practical way to understand why transmission continues despite repeated outbreak responses.
There is progress worth acknowledging. Our study shown that Nigeria’s disease surveillance architecture has improved through the Integrated Disease Surveillance and Response framework and digital tools that enable faster reporting and real-time monitoring across states.
Routine situation reports now provide clearer visibility of outbreak patterns and support earlier response actions. However, gaps remain. Delays in detection still occur where reporting systems are fragmented or partly manual, and technical capacity varies across regions.
Community participation in surveillance is inconsistent, leading to missed early signals. Differences in preparedness and resource allocation across local government areas also produce uneven response performance. Strengthening data use, workforce capacity, and community-linked reporting is therefore essential to translate improved surveillance into timely containment.
Because many drivers of Lassa fever sit outside the health sector, effective control depends on collaboration across multiple sectors. Our study established that agriculture, environment, housing, and local government institutions all influence rodent control, sanitation, and living conditions that shape exposure risk.
Community leadership is equally important for sustaining hygiene practices and improving risk communication. Universities and research institutes contribute evidence, innovation, and workforce training that strengthen preparedness. When these actors operate in isolation, interventions produce only temporary gains. Coordinated planning, shared data, and joint accountability are required. In practical terms, Lassa fever prevention is not just a medical responsibility—it is fundamentally a governance and systems coordination issue.
While national strategies are vital, everyday actions within households can significantly reduce risk. Food should be stored in sealed containers and kept off the floor to prevent contamination by rodents.
Homes and surroundings should be kept clean, with proper waste disposal and removal of bushes or clutter that attract rats. Simple rodent-control measures, including blocking entry points into houses, can reduce exposure. When symptoms such as persistent fever or unusual weakness occur, early presentation at a health facility is essential, as prompt treatment improves outcomes and limits spread. Delaying care or relying on self-medication often worsens complications. Preventing Lassa fever is therefore not only a government duty—prevention is everyone’s responsibility.
From a policy perspective, Lassa fever should be treated as a national health security priority rather than a seasonal emergency. Strengthening state-level surveillance systems will enable faster detection and coordinated response across high-burden areas. Sustained funding for infection prevention and control in hospitals, including protective equipment, isolation capacity, and continuous staff training, is essential to protect healthcare workers and maintain response capacity. Expanding access to timely and affordable diagnostics, particularly in rural communities, will reduce delays in confirmation and treatment.
Equally important is sustained investment in public awareness programmes that promote early care-seeking, safe food practices, and environmental sanitation. When these measures are implemented together, Lassa fever control moves beyond outbreak firefighting toward proactive preparedness.
Lassa fever outbreaks in Nigeria are increasingly predictable, but they are also preventable when early warning, environmental control, and timely care work together. With growing surveillance capacity and expanding research expertise, Nigeria is well-positioned to lead coordinated prevention efforts across West Africa. Investing in prevention, clean environments, safer food systems, protected health workers, and stronger community awareness is far less costly than repeated emergency responses. The path forward requires shared responsibility from government, institutions, and households alike. Ultimately, sustainable control will depend not on reacting to outbreaks, but on preventing them before they begin. Epidemics persist where prevention is neglected, but they retreat where systems, communities, and leadership act together.
Idowu ADEWUMI is a lecturer at the University of Medical Sciences, Ondo, Nigeria, a Health Information Management and Public Health Scholar and researcher, with interest in infectious disease prevention, surveillance, and outbreak response in Nigeria.
Email: adewumiidowupeter@gmail.com, padewumi@unimed.edu.ng