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. 2021 Aug 30;105(4):974-985.
doi: 10.4269/ajtmh.20-1160.

52 Years of Lassa Fever Outbreaks in Nigeria, 1969-2020: An Epidemiologic Analysis of the Temporal and Spatial Trends

Dennis E Agbonlahor  1 , George O Akpede  2 , Christian T Happi  3 , Oyewale Tomori  4
Affiliations

52 Years of Lassa Fever Outbreaks in Nigeria, 1969-2020: An Epidemiologic Analysis of the Temporal and Spatial Trends

Dennis E Agbonlahor et al. Am J Trop Med Hyg. .

Abstract

The year 2020 made 52 years since the first report of Lassa fever (LF) outbreaks from Nigeria, but what progress has been made in its control? We sought to answer this through an epidemiologic analysis of the temporal and spatial trends of the outbreaks from 1969 to 2020. The analysis showed an overall strengthening of the outbreaks, hallmarked by the change from irregular to regular annual and from limited local to nationwide outbreaks, while there was a sharp contrast between the upward trend in case numbers and downward trend in case fatality. Pending the availability of effective vaccines, greater effort is required to reverse the upward trend in case numbers and sustain the downward trend in case fatality. We discuss the factors associated with the observed trends as well as the prerequisites for further improvements.

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Figures

Figure 1.
Figure 1.
Trend in numbers and proportions of affected states during Lassa fever outbreaks in Nigeria, 1969–2020 (2 per. Mov. Avg. = 2 per moving averages). This figure appears in color at www.ajtmh.org.
Figure 2.
Figure 2.
Number of outbreak years and number of outbreak years per state as a proportion of the total number of national outbreak years of Lassa fever in Nigeria, 1969–2020 (ANOYs = average number of outbreak years). This figure appears in color at www.ajtmh.org.
Figure 3.
Figure 3.
Overall burden of Lassa fever outbreaks per state in Nigeria, 1969–2020. This figure appears in color at www.ajtmh.org.
Figure 4.
Figure 4.
Trend in numbers of clinically suspected cases of Lassa fever in Nigeria, 1969–2020 (2 per. Mov. Avg. = 2 per moving averages). This figure appears in color at www.ajtmh.org.
Figure 5.
Figure 5.
Trend in case fatality among clinically suspected cases of Lassa fever in Nigeria, 1969–2020. This figure appears in color at www.ajtmh.org.
Figure 6.
Figure 6.
Population incidence of suspected and confirmed cases, and case fatality among suspected cases of Lassa fever, 1969–1992 vs. 1993–2008 vs. 2009–2020. This figure appears in color at www.ajtmh.org.
See this image and copyright information in PMC

References

    1. Troup JM, White HA, Fom AL, Carey DE, 1970. An outbreaks of Lassa fever on the Jos Plateau, Nigeria, in January–February 1970. Am J Trop Med Hyg 19: 695–696. - PubMed
    1. Frame JD, Baldwin JM, Jr, Gocke DJ, Troup JM, 1970. Lassa fever, a new virus disease of man from West Africa I. Clinical description and pathological findings. Am J Trop Med Hyg 19: 670–676. - PubMed
    1. Leifer E, Gocke DJ, Bourne H, 1970. Lassa fever, a new virus disease of man from West Africa II. Report of a laboratory-acquired infection treated with plasma from a person recently recovered from the disease. Am J Trop Med Hyg 19: 677–679. - PubMed
    1. Buckley SM, Casals J, 1970. Lassa fever, a new virus disease of man from West Africa III. Isolation and characterization of the virus. Am J Trop Med Hyg 19: 680–691. - PubMed
    1. Akpede GO, Asogun DA, Okogbenin SA, Okokhere PO, 2018. Lassa fever outbreaks in Nigeria. Expert Rev Anti Infect Ther 16: 663–666. - PubMed

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