WAHO Leads United Front Against Lassa Fever in West Africa

The West African Health Organisation (WAHO), a specialized institution of the Economic Community of West African States (ECOWAS) responsible for health issues, is at the helm of an ongoing multistakeholder effort to rid West Africa of the debilitating zoonotic Lassa fever disease.

WAHO, in collaboration with the Nigerian Ministry of Health and Social Welfare, on Thursday, in Abuja, Nigeria, hosted the inaugural meeting of the Lassa Coalition Governing Entity (LGE), which aim to provide leadership and governance for the newly established Lassa Coalition, building upon existing regional and national efforts. 

The inaugural LGE meeting was supported by the Coalition for Epidemic Preparedness Innovations (CEPI), a global partnership working to accelerate the development of vaccines and other biologic countermeasures against epidemic and pandemic threats. The convening which was chaired by Nigeria’s Coordinating Minister of Health and Social Welfare, Prof. Muhammad Ali Pate, marks a significant step in unifying regional efforts to tackle Lassa fever.

The collaborative efforts of WAHO, the Nigerian government, and CEPI underscored the region’s commitment to combating Lassa fever as an important public health priority, with a primary focus on advancing progress in Lassa vaccine development. Thus, key objectives of the meeting included reviewing progress, identifying challenges, and formulating actionable steps to ensure the Lassa vaccine program’s success and sustainability in 2025. 

In February 2024, CEPI and WAHO had formalised their partnership through a Memorandum of Understanding (MOU), which sought to, among other things, establish a WAHO-led Lassa Coalition with support from CEPI. The overarching objective of the Coalition is to ensure West African countries affected by Lassa fever have access to a safe, effective, and high-quality vaccine.

Since then WAHO and CEPI, in partnership with ECOWAS Member States, have collaboratively advanced the Lassa Coalition which unites governments, regional organizations, global health institutions, researchers, and funding bodies to coordinate resources and efforts to effectively combat Lassa fever. Against this backdrop, the Abuja meeting sought to accelerate the development, deployment, and equitable access to Lassa fever vaccines.  

Vaccine Development as Panacea Against Future Lassa Outbreaks

While addressing a press during the meeting, Minister Pate emphasized the significance of the ongoing efforts in not only tackling Lassa fever but also enhancing the region’s preparedness for future health crises, emphasizing the catastrophic nature of Lassa fever hence the necessity to develop a vaccine for the disease.

“For over 50 years, Lassa fever has remained a recurring challenge in Nigeria and across West Africa, particularly during this season, with its high fatality rates and lack of preventative tools. The disease, a zoonotic infection, not only affects exposed populations but also claims the lives of health workers caring for infected patients. Until now, interventions have been limited to case management and therapeutic measures,” he noted.

Against this backdrop, the Nigerian health minister said thanks to robust scientific collaboration and partnerships among global and local institutions, there is now a deeper understanding of the disease. “Promising progress has been made with a vaccine candidate showing safety and potential efficacy. If sustained, these efforts could lead to the development of an effective Lassa fever vaccine capable of controlling the disease.” 

The Minister said the contagious nature of Lassa meant it does not respect administrative or political boundaries hence it calls for a joint multi-stakeholder effort to build a regional common. “We need to build a regional commons. So it’s about Ghana, Nigeria, Senegal, and others joining hands. No single country, no single institution can do this by itself. Lassa has been around for 50 years; it requires all of us working hand in hand to get rid of it.”  

On Lassa Vaccine Clinical Trials in West Africa

Dr. Richard Hatchett, CEO of the Coalition for Epidemic Preparedness Innovations (CEPI), also fielded questions from journalists at the press briefing including a question seeking clarification on why the first Lassa vaccine clinical trial was conducted in Ghana yet the second trial meant to take place in Nigeria as announced by Minister Pate in 2024 was has yet to commence. 

“The concept of the Lassa fever vaccine program is meant to include all of the countries that experience Lassa fever disease. And Nigeria, first and foremost, has always been the epicenter of the disease in terms of the number of cases. The first-ever Phase II Lassa vaccine clinical trial was held in Ghana while the first real field trial is now taking place in Nigeria, Liberia, and Sierra Leone. And the intent would be to test the vaccine across the entire region,” he said.

While responding to concerns about the potential Lassa fever mutations during outbreaks i.e whether it involves a single strain or multiple mutations, Dr Hatchett said: “A lot of the preparatory work that has been done is to understand the epidemiology of Lassa fever in Nigeria, but also across the West African region.”

The CEPI CEO underlined the differential nature of Lassa and how its manifestation varies by regions even within Nigeria: “It differs even within Nigeria. There are hotspots and then there are other areas where the disease clearly is, but not at the same level. Understanding that epidemiology carefully across the large region is going to help us design and target where the actual trials are conducted.” 

When questioned about when the Lassa vaccine would be ready, Dr. Hatchett said whereas their target was to have the vaccine ready by the end of the decade the coalition was unable to give specific dates. “Vaccine development doesn’t move like a mechanical production process such that you start it and it spits out a product at a specific time. It’s really important that we go through the right stages before we start the large trial, which will actually test whether the vaccine is fully effective in preventing Lassa disease.”

The CEPI CEO said the Phase 2a trial that was initiated in Nigeria in 2024 looks specifically at the safety and the immune response that the vaccine can elicit adding that they were now working towards a Phase 2b study before the next Lassa season to explore whether or not the vaccine actually protects those vaccinated against Lassa as well as understand how hard it is to actually implement the clinical trials in the hotspots where the disease is occurring.

As West Africa awaits the Lassa vaccine, governments have been urged to pre-position supplies, mobilize public health officers, and deploy antiviral therapies during outbreaks. Equally significant is addressing gender dimensions in Lassa research and ensuring women’s unique symptoms and needs are recognized and incorporated into vaccine development.

In the meantime, Minister Pate had assured that the Lassa Coalition will meet regularly to monitor the Lassa vaccine program’s progress and take actionable steps towards finalizing the vaccine, emphasizing Lassa preventive measures such as keeping food and water covered, limiting rodent access to homes, and seeking early medical care when symptoms appear. Whereas the LGE will meet once a year the Lassa Coalition’s national task forces will convene as needed to ensure the public remains informed.