Cases Of Lassa Fever Research Articles

Factors associated with late presentation for lassa fever treatment among symptomatic cases in Ondo State, Nigeria

Introduction: this study assesses the sociodemographic factors associated with late presentation among suspected Lassa fever (LF) cases in Ondo State, Nigeria. Late presentation was determined as presentation to treatment center after sixth day of onset of symptom.

Lassa fever cases suffer from severe underreporting based on reported fatalities.

Lassa fever is a viral haemorrhagic fever endemic to eight West African countries. Symptomatic disease is expected to occur in 20% of those infected and transmission typically occurs from viral spillover from rodent hosts. The combination of limited access to diagnostics and healthcare means the true burden of this disease is unknown. The case fatality rate among confirmed, probable and possible cases of Lassa fever in endemic regions is expected to be ≈15%. Here, annual reported cases and deaths have been used to estimate the case fatality rate, using three subsets of available data, to understand the scale of underreporting of severe human cases. The literature review produced 38 records of cases and fatalities, comprising 5230 reported cases and 1482 reported deaths in seven countries. The estimated case fatality rate ranges from 16.5 to 25.6% (standard deviation 11.5-32.2). The expected number of severe cases between 2012 and 2022 is 8995, with current reported numbers 58% of what is expected. This analysis highlights current uncertainty and systemic underreporting of the morbidity and mortality burden of Lassa fever in its endemic region and must be considered when discussing the epidemiology of this neglected tropical disease.

The COVID-19 Impact on the Trends in Yellow Fever and Lassa Fever Infections in Nigeria.

Lassa fever (LF) and yellow fever (YF) belong to a group of viral hemorrhagic fevers (VHFs). These viruses have common features and damages the organs and blood vessels; they also impair the body's homeostasis. Some VHFs cause mild disease, while some cause severe disease and death such as in the case of Ebola or Marburg. LF virus and YF virus are two of the most recent emerging viruses in Africa, resulting in severe hemorrhagic fever in humans. Lassa fever virus is continuously on the rise both in Nigeria and neighboring countries in West Africa, with an estimate of over 500,000 cases of LF, and 5000 deaths, annually. YF virus is endemic in temperate climate regions of Africa, Central America (Guatemala, Honduras, Nicaragua, El Salvador), and South America (such as Brazil, Argentina, Peru, and Chile) with an annual estimated cases of 200,000 and 30,000 deaths globally. This review examines the impact of the COVID-19 pandemic on the trend in epidemiology of these two VHFs to delineate responses that are associated with protective or pathogenic outcomes.

Analysis of sociodemographic and clinical factors associated with Lassa fever disease and mortality in Nigeria.

Over past decades, there has been increasing geographical spread of Lassa fever (LF) cases across Nigeria and other countries in West Africa. This increase has been associated with significant morbidity and mortality despite increasing focus on the disease by both local and international scientists. Many of these studies on LF have been limited to few specialised centres in the country. This study was done to identify sociodemographic and clinical predictors of LF disease and related deaths across Nigeria. We analysed retrospective surveillance data on suspected LF cases collected during January-June 2018 and 2019. Multivariable logistic regression analyses were used to identify the factors independently associated with laboratory-confirmed LF diagnosis, and with LF-related deaths. There were confirmed 815 of 1991 suspected LF cases with complete records during this period. Of these, 724/815 confirmed cases had known clinical outcomes, of whom 100 died. LF confirmation was associated with presentation of gastrointestinal tract (aOR 3.47, 95% CI: 2.79-4.32), ear, nose and throat (aOR 2.73, 95% CI: 1.80-4.15), general systemic (aOR 2.12, 95% CI: 1.65-2.70) and chest/respiratory (aOR 1.71, 95% CI: 1.28-2.29) symptoms. Other factors were being male (aOR 1.32, 95% CI: 1.06-1.63), doing business/trading (aOR 2.16, 95% CI: 1.47-3.16) and farming (aOR 1.73, 95% CI: 1.12-2.68). Factors associated with LF mortality were a one-year increase in age (aOR 1.03, 95% CI: 1.01-1.04), bleeding (aOR 2.07, 95% CI: 1.07-4.00), and central nervous manifestations (aOR 5.02, 95% CI: 3.12-10.16). Diverse factors were associated with both LF disease and related death. A closer look at patterns of clinical variables would be helpful to support early detection and management of cases. The findings would also be useful for planning preparedness and response interventions against LF in the country and region.

Emergence and Re-emergence of Lassa fever Cases in Bauchi State, Northeastern Nigeria, 2012 - 2021

Emergence and Re-emergence of Lassa fever Cases in Bauchi State, Northeastern Nigeria, 2012 - 2021

Increased Prevalence of Lassa Fever Virus-Positive Rodents and Diversity of Infected Species Found during Human Lassa Fever Epidemics in Nigeria.

ABSTRACTThe dynamics of Lassa virus (LASV) infections in rodent reservoirs and their endemic human caseloads remain poorly understood. During the endemic period, human infections are believed to be associated with the seasonal migration of Mastomys natalensis, thought to be the primary reservoir that triggers multiple spillovers of LASV to humans. It has become imperative to improve LASV diagnosis in rodents while updating their prevalence in two regions of Lassa fever endemicity in Nigeria. Rodents (total, 942) were trapped in Ondo (531) and Ebonyi (411) states between October 2018 and April 2020 for detection of LASV using various tissues. Overall, the LASV prevalence was 53.6%. The outbreak area sampled in Ondo had three and two times higher capture success and LASV prevalence, respectively, than Ebonyi State. This correlated with the higher number of annual cases of Lassa fever (LF) in Ondo State versus Ebonyi State. All rodent genera (Mastomys, Rattus, Crocidura, Mus, and Tatera) captured in both states showed slightly variable LASV positivity, with Rattus spp. being the most predominantly infected (77.3%) rodents in Ondo State versus Mastomys spp. (41.6%) in Ebonyi State. The tissues with the highest LASV positivity were the kidneys, spleen, and testes. The finding of a relatively high LASV prevalence in all of the rodent genera captured highlights the complex interspecies transmission dynamics of LASV infections in the reservoirs and their potential association with increased environmental contact, as well as the risk of zoonotic spillover in these communities, which have the highest prevalence of Lassa fever in Nigeria.IMPORTANCE Our findings show the highest LASV positivity in small rodents ever recorded and the first direct detection of LASV in Tatera spp. Our findings also indicate the abundance of LASV-infected small rodents in houses, with probable interspecies transmission through vertical and horizontal coitus routes. Consequently, we suggest that the abundance of different reservoir species for LASV may fuel the epizootic outbreaks of LF in affected human communities. The high prevalence of LASV with the diversity of affected rodents has direct implications for our understanding of the transmission risk, mitigation, and ultimately, the prevention of LF in humans. Optimal tissues for LASV detection in rodents are also presented.

Epidemiological characteristics of Lassa fever cases in Liberia: a retrospective analysis of surveillance data, 2019–2020

ObjectivesLiberia is endemic to Lassa fever (LF) and has the largest reported per capita incidence of LF patients in the West African region. Cases of the disease increased unprecedentedly in 2019 and 2020, characterized by a geographical drift in epidemiology and seasonal variation of occurrence. This study aims to describe the epidemiological and clinical characteristics of LF in Liberia from 2019 to 2020. MethodsA retrospective study was conducted on cases of LF confirmed at the National Public Health Reference Laboratory from January 2019 to December 2020. Medical records were reviewed, and epidemiological and clinical data were collected in an organized manner. Descriptive and inferential statistics were carried out using Epi Info (version 7.2.5.0). ResultsA total of 382 suspected LF cases were reported, of which 103 were laboratory-confirmed, yielding a case positivity rate of 27% (103/382). The median age of the LF cases was 20 (IQR: 9–30). Children younger than 18 years accounted for 40.8% (42/103) of the cases and healthcare workers’ cases constituted 7.7% of the cases. Bong, Nimba, and Grand Bass accounted for 87.4% of the cases with cases in new counties like Lofa, Margibi, and Grand Kru. Hemorrhage (aOR:10.2; 95% CI: 3.11–33.81), patients who did not receive ribavirin (aOR: 4.4; 95% CI: 1.12–17.57, P = 0.034), and patients aged 40 years or older (aOR: 6.2; 95% CI: 1.19–32.53, P = 0.049) were associated with LF mortality. ConclusionThe LF cases in 2019 and 2020 had a high case fatality rate and spread to new counties that had not previously reported LF. The disease occurred during most of the rainy season instead of the usual dry season. There is an urgent need to lower morbidity and mortality, improve early presentation to the hospital, and early initiation of appropriate medical care.

Epidemiological review of confirmed Lassa fever cases during 2016-2018, in Plateau State, North Central Nigeria.

Lassa fever (LF) is endemic in West Africa and constitutes a significant public health concern due to its potential for epidemics and associated high mortality. The first reported case and management of Lassa fever in Plateau State occurred more than 50 years ago. We set out to undertake a three-year epidemiological review of LF cases in Plateau State, North Central Nigeria. This is a retrospective study of all confirmed LF cases in Plateau State between 2016 and 2018. Plateau state Lassa fever- Line list and patient case records were used to extract relevant data. Lassa PCR was carried out at the NCDC accredited Laboratory network. Data analysis was done using STATA version SE14.1. Forty-four persons (44) had confirmed LF over the examined period, 18 (41%) in 2016, 15 (34%) in 2017 and 11 (25%) in 2018. The mean age was 29.7±14.6 years and 53% were males. Sixty-six percent (66%) of the patients resided in rural areas. It affected all local government areas (LGA) in the state except Pankshin, Jos East and Kanke LGAs. Twenty-five percent (25%) of the cases occurred among underprivileged communities of Jos North and another 25% in rural dwellers of Langtang North. Fifty-nine percent (59%) of cases occurred during the 1st quarter, 27% the 2nd quarter and 18% the 3rd quarter of the year. The case fatality rate was 57%. LF is endemic in Plateau State. Prevention strategies must be sustained year round and target the youth, urban and rural underprivileged communities. There is also need for case management improvement to reduce mortality.

A Case Report of Lassa Fever between Boundary Communities in Nigeria and Republic of Benin: A Call for International Collaboration

The spread of Lassa Fever (LF) cases across international borders call for cross-board management and collaboration. This case report describes a laboratory-confirmed index case of LF in Kwara state, Nigeria. The case of LF in Kwara state was a 30-year-old woman who presented with a history of fever, headache, and abdominal pain and had been treated for malaria. On 13th February 2020, the Kwara State Ministry of Health was notified of a suspected case of LF. The case visited health facilities in Kwara state, Nigeria, and the Republic of Benin during her illness. Blood samples were obtained from her, and she was confirmed a positive LF case in the Republic of Benin. Although LF diagnosis is challenging, multisectoral collaboration and effective community engagement within the framework of the International Health Regulations is required to control the LF outbreak promptly.

Beyond Lassa Fever: Systemic and structural barriers to disease detection and response in Sierra Leone.

BackgroundLassa fever (LF) often presents clinically as undifferentiated febrile illness. Lassa Fever cases in Sierra Leone have been falling since the 2014–2016 Ebola epidemic. Data from other LF endemic countries suggest that this is not a true reflection of local epidemiological decline, but rather a function of either health seeking behaviour or the health/referral system. In Sierra Leone, many other diseases present with a similar early clinical picture, including COVID-19 and Marburg Disease (which has recently emerged in neighbouring Guinea). This empirical study explores the implementation of health system processes associated with International Health Regulations (IHR) requirements for early detection and timely and effective responses to the spread of febrile disease, through the case study of LF in Sierra Leone.Methodology/Principal findingsThis study used a qualitative approach to analyse local policy and guidance documents, key informant interviews with policy and practice actors, and focus group discussions and in-depth interviews with health care workers (HCWs) and community health workers (CHWs) in Kenema District to examine the ways in which undifferentiated fever surveillance and response policies and processes were implemented in the post-Ebola period. Multiple challenges were identified, including: issues with the LF case definition, approaches to differential diagnosis, specimen transport and the provision of results, and ownership of laboratory data. These issues lead to delays in diagnosis, and potentially worse outcomes for individual patients, as well as affecting the system’s ability to respond to outbreak-prone disease.Conclusions/SignificanceIdentification of ways to improve the system requires balancing vertical disease surveillance programmes against other population health needs. Therefore, health system challenges to early identification of LF specifically have implications for the effectiveness of the wider Integrated Disease Surveillance and Response (IDSR) system in Sierra Leone more generally. Sentinel surveillance or improved surveillance at maternity facilities would help improve viral haemorrhagic fever (VHF) surveillance, as well as knowledge of LF epidemiology. Strengthening surveillance for vertical disease programmes, if correctly targeted, could have downstream benefits for COVID-19 surveillance and response as well as the wider health system—and therefore patient outcomes more generally.

Mortality among confirmed Lassa Fever cases in Ondo State, Nigeria, January 2017- March 2019: A cross sectional study

Background: Lassa fever (LF) is an acute viral haemorrhagic disease endemic in Ondo State, Nigeria. This study aimed to determine the factors associated with mortality among confirmed LF cases.
 Methods: A cross sectional study design was used by conducting a retrospective review of the records of all patients who had been treated for LF at the Federal Medical Centre, Owo since 2017 till March 2019. Descriptive statistics were done, case fatality rate was calculated. Chi square tests were used to explore associations. Logistic regression was used to identify the predictors of death. Data were analysed with SPSS version 23.0. P values ≤0.05 were statistically significant.
 Results: The median age was 34 years, and the inter-quartile range was 24-48 years. A total of 30 deaths (case fatality rate [CFR] = 10.9%) were recorded, of which 24 (15.5%) were males. Also, the fatality rate increased from 1.6% in 2017 to 10.5% in 2018 and 16.7% in 2019. During peak period, mortality recorded was 15(8.5%) and non-peak periods (April to December), 14(14.9%) was recorded (p=0.104). Fatality was 12.5% (1 out of 8) among pregnant women with 100% foetal death. Patients aged 18-45 years had 0.25 odds of dying (AOR = 0.25; 95%CI= 0.08, 0.76) compared to those aged ≥ 46 years. Those who commenced ribavirin ≥7 days (AOR 4.1; CI = 1.06, 15.42) and those with elevated urea level (AOR 7.5; CI = 2.5, 23.1) have more odds of dying.
 Conclusions: A well-coordinated LF outbreak response is needed both at LF peak non-peak periods.

Lassa fever in pregnancy: Report of two maternal deaths in a tertiary center in the middle-belt region of Nigeria.

Lassa fever is endemic in West Africa, with an estimated 300,000 to 500,000 infections occurring annually and approximately 5,000 deaths. Two Lassa fever cases in pregnancy with maternal and fetal complications were presented. The age range was 20 to 30 years and the range of parity was 1 to 3. The duration of symptoms was 13 to 14 days. Clinical presentation and complications common to the two cases were fever, abnormal bleeding, cough/sore throat, anaemia, IUFD/Stillbirth, and maternal deaths. Others are vomiting, restlessness/confusion, hypotension and thrombocytopaenia. Major challenges encountered are late presentation, delay in confirming diagnosis and instituting definitive treatment, limited facility, and the impact of traditional and religious factors in safe burial for Lassa fever cases. In resource-constrained settings; diagnosis, treatment and surveillance for Lassa fever may be challenging. Early clinical suspicion and appropriate case management are critical for good reproductive outcome.

COVID-19 and Lassa fever in Nigeria: A deadly alliance?

As the COVID-19 pandemic poses serious threats to global public health, Nigeria faces a potential public health crisis owing to COVID-19 and other infectious diseases, such as Lassa fever (LF) and malaria. In this study, we discuss the possible determinants behind the decreased number of LF cases in Nigeria, which was likely due to the synergistic impact of the COVID-19 pandemic. During the COVID-19 pandemic, the epidemic curve of LF seems to have deviated from the general seasonal scale seen in past years, which could be due to underreporting of cases. In addition, partial compliance with nonpharmaceutical interventions, limited resources, or human behavior could be contributing factors. Thus, we suggest that better differentiation in terms of human and resource allocation between COVID-19 and LF could help curtail the transmission effectively.

A GIS-BASED APPROACH TO RISK MAPPING OF LASSA FEVER OUTBREAK IN AKURE SOUTH LOCAL GOVERNMENT AREA, NIGERIA

Abstract. Lassa fever is an acute viral illness, which is endemic in some counties in West Africa, including Guinea, Liberia, Sierra Leone and parts of Nigeria. It is caused by the Lassa virus, which is primarily hosted by multi-mammate rats that live in and around houses. This study sees the need to enhance public awareness by producing risk maps of Lassa fever for the study area. In a bid to understand and predict the prevalence of the disease in Akure South Local Government Area. Temporal and spatial analyses of Lassa fever cases were carried out, information about related environmental variables such as temperature, rainfall, vegetation, and elevation were obtained. These data sets from primary and secondary sources were integrated independently as predictor variables for the developed risk model. The accessibility of incidences of Lassa fever to health centres was determined and analysed. The risk map produced indicates that areas about the Ijoka community are at higher risk of being affected by a future Lassa fever outbreak than other areas. The model developed an understanding of the high risk and potential outbreak of Lassa fever to alert the general public of the virus to curb the future outbreak. However, future research can be on the control and prevention of Lassa fever in the study area.

Clinical Presentations of Lassa Fever in Non-Endemic Parts of the World: A Systematic Review

Background: Lassa fever cases outside Africa are seen as imported cases of Lassa fever. Timely diagnosis of imported Lassa fever is important for timely intervention necessary to reduce the morbidity and mortality associated with Lassa fever, and this requires the knowledge of the clinical manifestations of Lassa fever. Purpose: This review was done to see how clinical diagnosis of imported Lassa fever can be facilitated based on the clinical presentations of imported cases of Lassa fever in Lassa fever non-endemic region. Methods: The relevant articles for the review were obtained from the databases of PubMed and Google Scholar. Results: The clinical presentations of the imported Lassa fever cases consisted of multisystem involvement and were similar to those of Lassa fever patients who were treated in the Lassa fever endemic region. Conclusions: History of recent travel to, or residence in, Lassa fever endemic region is an important clue for clinical diagnosis of Lassa fever. The 2011 CDC surveillance case definition and the modified Khan case definition for Lassa fever may aid clinical diagnosis of Lassa fever. Any clinically suspected case of Lassa fever should have a laboratory confirmation.

The Role of Weather in the Spread of Lassa Fever in Parts of Northern Nigeria

This study employed multiple regression analysis to evaluate the impact of weather variables (relative humidity, rainfall amount and maximum temperature) on the reported number of Lassa fever cases and to assess the strength of relationship between same for thirteen states in northern Nigeria (Adamawa, Bauchi, Jigawa, Borno, Kaduna, Katsina, Kano, Kebbi, Sokoto, Taraba, Yobe, Zamfara and Gombe states) over a five-year period (2016-2020). Secondary data on Lassa fever disease and weather variables were described on a weekly basis from the data base of the Nigeria Centre for disease control (NCDC) as well as weather variables from the National Aeronautics Space Administration, U.S.A. (NASA). The study seeks to establish the role of weather in the occurrence of Lassa fever in parts of Northern Nigeria and also to evaluate the impact of these weather variables on the occurrence of the disease. The study reveals that these weather variables accounted for 70% (r2=0.70) of the cases of Lassa fever reported in Northern Nigeria. It occurred all year round but cases peaked during the dry months, from December to March where relative humidity is low and rainfall amount small. At confidence level of 0.05, there was a significant (p=0.000) strong positive correlation of r=0.83 between Lassa fever cases and weather variables. Of the three weather parameters, maximum temperature had a weak positive and insignificant (p=0.3) relationship with Lassa fever while relative humidity and rainfall had strong and moderate negative relationships of r = -0.7 and r = -0.5 respectively which were both significant at (r2=0.000). In conclusion, there is need to cultivate sufficient preparedness strategies in order to cope with the burden to ensure general wellbeing of people resident in these affected areas using these weather parameters.

Statistical Distribution of Lassa Fever in Edo State, Nigeria

Lassa fever is a severe viral infection caused by the Lassa virus and spread by contact with excretions or secretions of infected rats gaining access to food and water inside human houses and other human activity areas. Sierra Leone, the Republic of Guinea, Nigeria, and Liberia are among the nations where it is endemic with a high number of deaths recorded yearly due to Lassa fever. In Nigeria, one of the states with the highest incidence is Edo. In order to reduce and predict the spread of Lassa fever in Edo state, the trend of the disease needs to be understood. Knowledge of the statistical distribution of a disease is one of the best ways to understand the trend of the disease. Currently, existing research on the statistical distribution of Lassa fever is very rare. The present work is an attempt to initiate research on the statistical distribution of Lassa fever with data obtained on weekly cases of Lassa Fever in Edo State, Nigeria. Based on the Kolmogorov Smirnoff and Anderson Darling’s goodness of fit test for fitting distribution, the Geometric distribution outfitted the weekly confirmed incidences of Lassa fever in Edo State, Nigeria when compared with the Discrete Uniform and Poisson distributions. The study further revealed that on the average, two Lassa fever cases is recorded per week in Edo State within the study period. This number of cases per week is on the high side and should be immediately looked into.

Differential pathogenesis of closely related 2018 Nigerian outbreak clade III Lassa virus isolates.

Nigeria continues to experience ever increasing annual outbreaks of Lassa fever (LF). The World Health Organization has recently declared Lassa virus (LASV) as a priority pathogen for accelerated research leading to a renewed international effort to develop relevant animal models of disease and effective countermeasures to reduce LF morbidity and mortality in endemic West African countries. A limiting factor in evaluating medical countermeasures against LF is a lack of well characterized animal models outside of those based on infection with LASV strain Josiah originating form Sierra Leone, circa 1976. Here we genetically characterize five recent LASV isolates collected from the 2018 outbreak in Nigeria. Three isolates were further evaluated in vivo and despite being closely related and from the same spatial / geographic region of Nigeria, only one of the three isolates proved lethal in strain 13 guinea pigs and non-human primates (NHP). Additionally, this isolate exhibited atypical pathogenesis characteristics in the NHP model, most notably respiratory failure, not commonly described in hemorrhagic cases of LF. These results suggest that there is considerable phenotypic heterogeneity in LASV infections in Nigeria, which leads to a multitude of pathogenesis characteristics that could account for differences between subclinical and lethal LF infections. Most importantly, the development of disease models using currently circulating LASV strains in West Africa are critical for the evaluation of potential vaccines and medical countermeasures.

Pathology and Pathogenesis of Lassa Fever: Novel Immunohistochemical Findings in Fatal Cases and Clinico-pathologic Correlation.

Lassa fever is a zoonotic, acute viral illness first identified in Nigeria in 1969. An estimate shows that the "at risk" seronegative population (in Sierra Leone, Guinea, and Nigeria) may be as high as 59 million, with an annual incidence of all illnesses of 3 million, and fatalities up to 67 000, demonstrating the serious impact of the disease on the region and global health. Histopathologic evaluation, immunohistochemical assay, and electron microscopic examination were performed on postmortem tissue samples from 12 confirmed Lassa fever cases. Lassa fever virus antigens and viral particles were observed in multiple organ systems and cells, including cells in the mononuclear phagocytic system and other specialized cells where it had not been described previously. The immunolocalization of Lassa fever virus antigens in fatal cases provides novel insightful information with clinical and pathogenetic implications. The extensive involvement of the mononuclear phagocytic system, including tissue macrophages and endothelial cells, suggests participation of inflammatory mediators from this lineage with the resulting vascular dilatation and increasing permeability. Other findings indicate the pathogenesis of Lassa fever is multifactorial and additional studies are needed.

Characteristics of Lassa Fever Outbreak in Ondo State, Nigeria, Year 2019

Background: Lassa fever (LF) is an acute viral haemorrhagic illness of a 2–21-day incubation period that occurs in West Africa. It is endemic in Nigeria and peaks during the first 12 weeks of the year. On January 22, 2019, the Nigeria Centre for Disease Control (NCDC) declared an outbreak of LF following an upsurge of LF cases in the country. A total of 213 confirmed cases including 41 deaths were reported from sixteen states including Ondo State. A multi-sectoral national rapid-response-team (RRT) was deployed to Ondo State to characterise the outbreak, assess its determinants, and institute control measures. Methods: An Emergency Operations Center (EOC) was activated to coordinate activities. We defined a suspected case as anyone with one or more of the following symptoms: malaise, fever, headache, sore throat, cough, vomiting and either history of contact with rodents, or a probable or confirmed LF case in the past 21 days, or any person with inexplicable bleeding between January 1, 2019, to February 26, 2019, in Ondo State. A confirmed case was any suspected case with laboratory confirmation. We conducted active case search, collected data using the LF case investigation form and reviewed the existing line list. We conducted contact tracing in hospitals and affected Local Government Areas (LGA). Data was analysed using and Epi info 7.0. Results: We identified 287 LF suspected cases in 6 LGAs; 118 were confirmed with 21 deaths (case fatality rate: 17.8%). The mean age was 39.2 ±20 years with a male-to-female ratio of 1.3:1. Of the 1,269 contacts line-listed, 20 became symptomatic, while 14 (70.0%) were confirmed positive. The secondary attack rate was 1.1%. Conclusion: The confirmed cases were more of primary cases, hence the need to focus more on reducing rodent-to-human transmission of LF. We recommend continuous education on community and health facility infection prevention control, contact tracing and enforcement of environmental sanitation measures across the state to mitigate future outbreaks