Center for One Health and Zoonotic Diseases (COHAZD)
We are leading Africa’s One Health and Zoonotic Disease Control, Prevention and Digital Transformation
About the Center
The Center for One Health and Zoonotic Diseases is Africa’s forward command for predicting, preventing, and controlling diseases before they become disasters. We fuse science, surveillance, and digital innovation to stop outbreaks at their source , not after headlines break. From zoonotic disease intelligence to digital health systems, we are building Africa’s frontline defense for a safer, healthier, more resilient future.
Surveillance & Biosecurity
Community Advocacy & Partnership
Digital Management & Transformation
Key Focus Areas
Computational Analysis & Big Data Management
Interdisciplinary Research & Intervention
Policy Advocacy & Government Partnerships
February 20, 2026
LASSA FEVER: OUTBREAK, TRENDS, SYMPTOMS, PREVENTION, & DIAGNOSIS
- Peace Oregbesan, SRHIN
Lassa fever is an acute viral haemorrhagic illness caused by the Lassa virus, first identified in Nigeria in 1969. It is endemic in West Africa, with Nigeria often recording the highest number of annual cases. Outbreaks occur most frequently between October and May, making the dry season a period of heightened risk.
The virus is primarily transmitted from infected rodents (Mastomys natalensis) to humans, and it continues to pose significant public health challenges due to environmental, social, and infrastructural factors.
Poor waste management, overcrowded housing, and improper food storage significantly increase risk.
Credit: NIAID
How Lassa Fever Spreads in Nigeria
1. Rodent-to-Human Transmission
The multimammate rat (Mastomys natalensis) serves as the natural reservoir for the virus. These rodents commonly inhabit and surround homes in many Nigerian communities. Humans become infected when they:
- Touch food or household items contaminated with rodent urine or feaces
- Inhale tiny particles from contaminated dust
- Come into direct contact with rodents
2. Human-to-Human Transmission
Although less common, human-to-human transmission occurs through:
- Contact with the blood, vomit, urine, saliva, or other bodily fluids of an infected person
- Poor infection control in healthcare settings
- Caregiving without protective equipment
Current Outbreak Trends
In 2025, Nigeria recorded over 955 confirmed cases and 176 deaths, and recent outbreaks in 2026 have affected multiple states, with hundreds of confirmed cases and a significant number of deaths. The states most frequently impacted include:
- Edo
- Ondo
- Bauchi
- Taraba
- Ebonyi
- Plateau
These patterns underscore the continued endemicity of the disease and the need for sustained preventive action.
Symptoms: What to Look Out For
Lassa fever has an incubation period of 2 to 21 days, and early symptoms often resemble malaria, making diagnosis challenging without laboratory testing.
Early Symptoms
- Persistent fever
- Weakness and tiredness
- Headache
- Sore throat
- Muscle aches
- Nausea or vomiting
- Chest or abdominal pain
Severe Symptoms
If untreated, the disease may progress to more severe conditions, including:
- Facial swelling
- Difficulty breathing
- Bleeding from the mouth, gums, or nose
- Shock
- Confusion
- Seizures or coma
Most Vulnerable Groups
- Pregnant women, especially in the third trimester
- Children and the elderly
- People with underlying health condition
Many survivors also develop temporary or permanent hearing loss
Preventive Measures: How to Stay Safe
Because there is no approved vaccine yet, prevention remains the most powerful tool against Lassa fever. Key protective measures include:
1. Rodent Control at Home
- Store food in tightly covered, rodent-proof containers
- Keep homes and surroundings clean
- Dispose of garbage far from living areas
- Seal holes and cracks that allow rodent entry
- Avoid drying food in open spaces where rodents may contaminate it
2. Community and Personal Prevention
- Store food in tightly covered, rodent-proof containers
- Avoid contact with rodent droppings
- Store grains properly to prevent rodent infestation
- Educate family and community members on symptoms and risks
3. Healthcare Setting Precautions
- Use appropriate personal protective equipment (PPE)
- Implement strict infection prevention and control (IPC) measures
- Immediately isolate suspected or confirmed cases
- Handle laboratory samples safely
These practices protect both health workers and the broader community
Diagnosis and Management
Prompt diagnosis saves lives. Because early symptoms mimic malaria and typhoid fever, any fever that does not respond to malaria treatment should raise suspicion.
Diagnosis
Lassa fever is confirmed through laboratory tests, including:
- PCR tests
- Antigen detection tests
- Antibody tests
Treatment
There is no universal cure, but early treatment significantly improves survival.
- Supportive care is the cornerstone: rehydration, fever control, monitoring vital organs
- Early presentation to a designated treatment center is critical
Why Early Care Matters
Most Lassa fever deaths occur due to late presentation, as many people initially treat symptoms as malaria at home. Early hospital care increases the chances of recovery and reduces complications.
Partners & Funders
Our projects have been funded and supported by the following instiutions
Explore some of our impactful and life-changing programs
Canada-Africa MPox Project
We are leading Nigeria’s community research and advocacy component on Mpox (formerly ‘Monkeypox’) for the Canada-Africa Mpox project across several states in Nigeria
#EliminateTrachoma
The Trachoma project aims to assess the impact of an innovative health education programme on trachoma knowledge in IDP camps in Abuja, Nigeria. T
Covid-19 Project
The Youth COVID-19 Vaccination Advocacy program is SRHIN’s latest initiative aimed at increasing awareness and promoting vaccination in communities across Ethiopia.