Outbreak Investigation of Lassa Fever in Ebonyi State

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DOI: 10.21522/TIJPH.2013.SE.19.02.Art021

Authors : Joseph Gbenga Solomon, Rowland Utulu, Azuka Adeke, Adejoke Akano, Emmanuel Omomoh, Nkechi Ebere, Sophia Usuwa, Adunola Oyegoke, Ihekerenma Okoli, Christian Akpa, Chukwuemeka Oguano


Background: Lassa fever is a viral haemorrhagic disease caused by an RNA virus of the family Arenaviridae. The seroprevalence in Nigeria is about 21%. Since 1969, several outbreaks reported in various states in Nigeria. The objective of this study was to investigate and control the Lassa fever outbreak in Ebonyi State, Nigeria.

Methodology: A cross-sectional study was done with laboratory confirmation. Sociodemographic data were collected and recorded on a line list and used for descriptive epidemiology. Blood samples were collected for confirmation by reverse transcriptase-polymerase chain reaction.

Findings: From January 22nd to March 1st, 2019 a total of 92 suspected cases were identified; with most being between 15-44 years, (59.1%), female (62.5%) and from Abakaliki LGA (47.6%). There were 30 laboratory-confirmed cases and 12 deaths with a case fatality rate (CFR) of 40%. Following confirmation, the incidence was highest in those aged 15-44 years (66.7%), and the CFR was highest in the same age group (58.3%). Disaggregated CFR showed a CFR of 25% in males and 50% in females. The Number of days from onset of symptoms to the presentation at the health facility was statistically significant with an odds ratio of 1.3 (1.009-1.700). (P-value < 0.05).

Conclusion: Poor health-seeking behaviour increases the chance of death from Lassa fever infection. It is essential to continue to institute preventive measure like health promotion. it will increase awareness on signs and symptoms as well as service availability of health for Lassa fever management.

Keywords: Lassa fever, Arenaviridae, Incidence, Disease Outbreak.


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