Earlier in October, the Nigeria Centre for Disease Control (NCDC) released an update that 172 people have died from Lassa fever so far this year, and we thought to put together a long-read explainer on this killer infection.
For most Nigerians, the name “Lassa” floats in the news like another strange illness, something that happens “somewhere else.”
But behind those numbers are real communities, families, and fears, and a reminder that our health and our environment are more connected than many realise.
What exactly is Lassa fever?
Lassa fever is a viral disease named after a small town in Borno State, where it was first identified in 1969.
It is caused by the Lassa virus, which lives inside a type of rodent called the multimammate rat (Mastomys natalensis). These rats are found almost everywhere across the country, in farms, markets, kitchens, and food stores.
Humans get infected when they come into contact with the rats’ urine or droppings, often through contaminated food or household items. In some cases, the virus spreads from person to person through contact with body fluids such as blood or saliva.
In simpler terms, Lassa fever is a disease that begins in the dirt and ends in the body. It is both a health problem and an environmental one.
How big is the problem?
The NCDC’s latest figures show that by October 2025, Nigeria had recorded over 1,200 confirmed cases and 172 deaths across more than half of the country’s 36 states.
States like Edo, Ondo, Bauchi, Taraba, and Ebonyi remain the most affected, together accounting for about 70% of total infections.
The proportion of infected people who die hovers around 15%, making Lassa fever one of Nigeria’s deadliest recurring epidemics.
It’s not new. Between 2018 and 2024, more than 20,000 suspected cases were recorded nationwide, according to the NCDC. And every dry season, the numbers rise sharply.
For 2024, a report indicated 214 deaths. And the age group most affected in Nigeria has often been 21–30 years, though all ages can be infected.
For those infected, symptoms are said to begin 5 to 21 days after exposure. It starts mildly then worsens into vomiting, diarrhoea, chest pain, and in severe cases, bleeding from the mouth, nose, or eyes.
Even survivors often pay a price as experts have said that about one in three people who recover lose part of their hearing permanently. It is serious.
Question then is, why does it keep coming back?
Well, there are three main reasons why Nigeria is stuck in this cycle:
1. The same rodents that spread Lassa fever thrive in dirty environments. Open waste dumps, scattered food remnants, and unsealed homes provide easy breeding grounds.
2. Many people do not understand how Lassa fever spreads. It often starts like malaria with fever, headaches, weakness, so patients delay seeking proper care. By the time they arrive at a hospital, it may be too late.
3. Across Nigeria, few health facilities are equipped with isolation wards or enough protective gear. There are also reports that in some rural areas, healthcare workers still treat suspected Lassa patients without gloves. That is risky!
How we treat the environment comes right back at us!
Sadly, the Lassa outbreak is a mirror reflecting Nigeria’s environmental habits.
When waste piles up in open dumps, when grains are stored in unsealed bags, when we share homes with rodents, we invite this disease and more.
In many rural communities, rodents are drawn to leftover food thrown carelessly in the open. Poor sanitation, lack of proper waste disposal, and open defecation make the situation worse.
It’s a reminder that public health begins with public hygiene.
How can we fight the virus?
When it comes to health and environment, there is always a good news. The Lassa virus is preventable, and here are some simple, consistent habits you can engage in to keep the virus away:
– Keep food covered and sealed. Store grains and leftovers in metal or glass containers.
– Dispose of waste properly. Don’t let garbage pile up near our homes or our markets.
– Block rodent entry points. Seal cracks and holes in your walls and doors.
– Maintain cleanliness. Sweep regularly, keep your kitchen dry and tidy.
– Seek medical help early. If you have persistent fever that doesn’t respond to malaria drugs, get tested for Lassa.
– And for health workers, it is proper to always wear gloves and protective gear when treating patients.
In conclusion, if every Nigerian understands the link between hygiene, environment, and health, we can break this deadly cycle. Because Lassa fever doesn’t start in the hospital, it starts in the home. And that’s exactly where the fight must begin
Food & Wellbeing1 year ago