Misdiagnosed as Malaria: How Delayed Lassa Fever Detection Is Silently Killing Nigerians

Every year, across hospitals and clinics in Nigeria's middle belt and beyond, a deadly pattern repeats itself with quiet and devastating regularity. 

A patient arrives with fever, weakness, and general body pain. The attending health worker  often working without adequate diagnostic equipment, in an understaffed facility, under enormous patient pressure  makes the most instinctive call available: malaria. 

Treatment begins. Days pass. The patient does not improve. By the time the true diagnosis of Lassa fever is considered and confirmed, it may already be too late.

This scenario, documented in a new Premium Times investigation published this week, captures what public health experts are calling one of Nigeria's most dangerous and underappreciated health crises.

 Lassa fever  a viral haemorrhagic disease endemic to West Africa and spread primarily through contact with infected multimammate rats  kills an estimated 5,000 Nigerians every year. 

The true figure may be significantly higher, because the diagnostic gap means that many Lassa deaths are never correctly identified.

Why Lassa Fever Gets Confused With Malaria

The clinical overlap between Lassa fever and malaria is genuine and significant. Both conditions present with fever, headache, fatigue, and muscle pain in their early stages. 

In a resource-constrained healthcare setting where rapid diagnostic tests for malaria are available but Lassa fever PCR tests are not, the path of least resistance is always to treat for malaria and hope for the best.

This diagnostic default is compounded by a lack of awareness at the frontline healthcare level.

Many community health workers, nurses, and even some general practitioners in rural and semi-urban settings have limited experience with Lassa fever and may not immediately consider it in the differential diagnosis. 

The disease is endemic primarily in states like Edo, Ondo, Bauchi, Ebonyi, and Taraba — but as population movement increases, cases are increasingly appearing in states that were previously considered low-risk.

There is also a fear factor at play. Lassa fever is a notifiable disease with serious infection control implications. 

A confirmed Lassa case requires the isolation of the patient, contact tracing, and the implementation of barrier nursing procedures that many Nigerian health facilities are simply not equipped to carry out. 

For some healthcare workers, the unspoken incentive is to avoid a diagnosis that will trigger obligations they cannot meet  a perverse dynamic that costs lives.

The Cost of Late Diagnosis

The consequences of delayed Lassa fever diagnosis are severe at both the individual and public health levels. 

At the individual level, early treatment with antiviral medication  specifically ribavirin  is significantly more effective when started in the first week of illness. 

For every day that passes with incorrect treatment, the window for effective intervention narrows. Patients who reach specialist care late are far more likely to die or suffer serious complications including deafness, which affects a significant proportion of Lassa fever survivors.

At the public health level, delayed diagnosis means delayed containment. 

Lassa fever spreads through direct contact with infected body fluids, meaning that healthcare workers who treat an undiagnosed Lassa patient without appropriate precautions are at risk of nosocomial infection. 

Several documented outbreaks in Nigeria have begun with a healthcare worker who unknowingly treated a Lassa patient without protective equipment  a tragedy that is preventable with timely diagnosis and proper protocols.

What Nigeria's Health System Needs

Public health experts have identified several concrete interventions that could significantly reduce Lassa fever mortality in Nigeria. First and most urgently, the expansion of diagnostic capacity is critical. 

Nigeria currently has only a handful of laboratories capable of performing the PCR tests required to confirm Lassa fever. 

Bringing that capacity closer to endemic communities  through mobile laboratories, regional reference centres, and point-of-care testing  would dramatically reduce the time between symptom onset and correct diagnosis.

Second, frontline healthcare worker training must be strengthened. 

The Nigeria Centre for Disease Control has made progress on this front, but the reach of training programmes remains inadequate relative to the number of primary healthcare workers across endemic states. 

Regular refresher training, clinical decision support tools, and clear referral pathways would help ensure that Lassa fever is considered earlier in the diagnostic process.

Third, community awareness must be enhanced. Many Nigerians in endemic areas are unaware of the connection between rats, contaminated food or surfaces, and Lassa fever. 

Simple public health messaging about rodent control, food storage, and the importance of seeking care early when fever does not respond to malaria treatment could save lives at minimal cost.

The Broader Healthcare Context

The Lassa fever diagnostic crisis does not exist in isolation. It is a symptom of a healthcare system that has been chronically underfunded, understaffed, and under-equipped for decades. Nigeria spends less than 5% of its national budget on health  well below the 15% commitment made under the Abuja Declaration in 2001. 

The consequences of that underinvestment are felt across every disease category, from maternal mortality to childhood vaccination rates, to the diagnostic failures that allow Lassa fever to masquerade as malaria until it is too late.

There is also the issue of Nigeria's estimated 2.1 million "zero-dose" children  those who have never received a single vaccine. 

This statistic, highlighted this week in reporting on Nigeria's immunisation challenges, reflects the same structural failures that underpin the Lassa fever crisis: a health system that is too fragmented, too underfunded, and too unevenly distributed to reach those who need it most.

Fixing these challenges is not simple or cheap. But the alternative  a healthcare system that continues to misdiagnose preventable deaths while the resources to do better exist  is morally and economically unsustainable. 

Nigeria loses not only lives to these diagnostic failures, but economic productivity, family stability, and the human potential of every person who dies of a treatable illness simply because the right test was not available at the right time.

The Lassa fever crisis is not an inevitable tragedy. It is a policy choice — and it can be reversed.