Geographies in Depth

Nigeria is already dealing with a deadlier viral outbreak than COVID-19

Ecologist James Koninga anesthetises a Mastomys Natalensis rodent with Isoflurane ether in the village of Jormu in southeastern Sierra Leone February 8, 2011. Lassa fever, named after the Nigerian town where it was first identified in 1969, is among a U.S. list of "category A" diseases - deemed to have the potential for major public health impact - alongside anthrax and botulism. The disease is carried by the Mastomys Natalensis rodent, found across sub-Saharan Africa and often eaten as a source of protein. It infects an estimated 300,000-500,000 people each year, and kills about 5,000. Picture taken February 8, 2011.

Lassa fever is a 'Class A' disease. Image: REUTERS/Simon Akam

Our Impact
What's the World Economic Forum doing to accelerate action on Geographies in Depth?
The Big Picture
Explore and monitor how COVID-19 is affecting economies, industries and global issues
A hand holding a looking glass by a lake
Crowdsource Innovation
Get involved with our crowdsourced digital platform to deliver impact at scale
Stay up to date:


  • Cases of Lassa fever have seen a sharp rise - from 64 in 2015 to 774 so far this year.
  • Fatality rates in 2019 reached 23%, compared to 2% for the coronavirus.

The detection of Covid-19 coronavirus in Nigeria raised early concerns about the country’s capacity to handle a major epidemic but so far local public health officials have been commended for handling the outbreak with aplomb.

But the coronavirus is not the only viral outbreak in Africa’s most populous country. Nigeria is currently dealing with what is turning out to be the world’s largest epidemic of Lassa fever, a viral disease deadlier than coronavirus.

Lassa fever is a severe viral hemorrhagic fever (VHF) like Ebola and Marburg that occurs throughout the year in Nigeria and was declared an “active outbreak” by the Nigeria Centre for Disease Control (NCDC) five weeks into 2020. The epidemic which occurs during the annual dry season (roughly November through March) has spread across half the country.

The Lassa fever virus is transmitted to humans through contact with food or household items contaminated with urine and feces of a rat. It’s also known to spread from person-to-person through contact with the body fluids and organs of infected persons, which has resulted in healthcare workers easily getting infected; some have died.

The epidemic, whose rapid escalation started right from the second week of the year, had by the end of the ninth week seen 774 cases and 132 deaths spread across 26 of Nigeria’s 36 states and the federal capital territory.

Troubling trends

In the past five years, there have been four epidemics—all having over 59% of total cases—in the first quarter of the year. In just nine weeks into 2020 Lassa fever cases are already 96% of total cases in 2019, the year with the largest Lassa epidemic with 810 cases and 167 deaths. As recently as 2015, the total number of cases was 64. This trend does not only suggest that the current epidemic will likely surpass that of 2019, but it also suggests a longer lasting and more devastating epidemic.

Lassa fever cases in Nigeria
There has been a sharp rise in the number of Lassa fever cases in 2020 Image: Quartz

Arenaviruses, which include the Lassa virus, are disproportionately prone to genetic mutations and have a propensity for spread if not adequately controlled, says Dr Olubusuyi Moses Adewumi, a specialist in arenaviruses and virologist at the College of Medicine, University of Ibadan in southwest Nigeria.

Dr. Adewumi blames the rapid increase of the epidemic each year on the lack of an effective surveillance system in place to identify and monitor the circulation of the virus in the country via rodents and other animals. “In our environment, the vectors continue to have the opportunity to interact with the human population and consequently spread the virus unchecked,” he explains.

Lassa fever is known to have a high mortality rate with Case Fatality Ratio (CFR) as high as 23% recorded for the first quarter of 2019—far deadlier than the Covid-19 coronavirus which currently has an estimated CFR of 2%.

Before the emergence of the new coronavirus, the NCDC has been focused mainly on Lassa fever. However, tweets from the NCDC’s twitter handle suggests recent online publicity is focused more on the coronavirus epidemic despite the reports of an unprecedented Lassa fever epidemic in the country.

“The international health agency and media deserve to give more attention to coronavirus considering its propensity for a pandemic,” says Dr. Adewumi. “LFV is our local problem in this part of the continent, hence, it is our responsibility to ensure the epidemic is controlled,” he said.

Don't miss any update on this topic

Create a free account and access your personalized content collection with our latest publications and analyses.

Sign up for free

License and Republishing

World Economic Forum articles may be republished in accordance with the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International Public License, and in accordance with our Terms of Use.

The views expressed in this article are those of the author alone and not the World Economic Forum.

Related topics:
Geographies in DepthGlobal RisksHealth and Healthcare Systems
World Economic Forum logo
Global Agenda

The Agenda Weekly

A weekly update of the most important issues driving the global agenda

Subscribe today

You can unsubscribe at any time using the link in our emails. For more details, review our privacy policy.

More on Geographies in Depth
See all

Asia-Pacific: How the region is prioritizing a green economy

Kanni Wignaraja and Debora Comini

June 10, 2024

About Us



Partners & Members

  • Join Us

Language Editions

Privacy Policy & Terms of Service

© 2024 World Economic Forum