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. 2023 Mar 30;18(3):e0283643.
doi: 10.1371/journal.pone.0283643. eCollection 2023.

A prospective, multi-site, cohort study to estimate incidence of infection and disease due to Lassa fever virus in West African countries (the Enable Lassa research programme)-Study protocol

Suzanne Penfold  1 , Ayola Akim Adegnika  2   3   4 , Danny Asogun  5 , Olufemi Ayodeji  6 , Benedict N Azuogu  7 , William A Fischer 2nd  8 , Robert F Garry  9 , Donald Samuel Grant  10 , Christian Happi  11 , Magassouba N'Faly  12 , Adebola Olayinka  13 , Robert Samuels  10 , Jefferson Sibley  14 , David A Wohl  8 , Manfred Accrombessi  2 , Ifedayo Adetifa  13 , Giuditta Annibaldis  15 , Anton Camacho  16 , Chioma Dan-Nwafor  13 , Akpénè Ruth Esperencia Deha  2 , Jean DeMarco  8 , Sophie Duraffour  15 , Augustine Goba  10 , Rebecca Grais  16 , Stephan Günther  15 , Énagnon Junior Juvénal Prince Honvou  2 , Chikwe Ihekweazu  13 , Christine Jacobsen  15 , Lansana Kanneh  10 , Mambu Momoh  10 , Aminata Ndiaye  16 , Robert Nsaibirni  16 , Sylvanus Okogbenin  5 , Chinwe Ochu  13 , Ephraim Ogbaini  5 , Énagnon Parsifal Marie Alexandre Logbo  2 , John Demby Sandi  10 , John S Schieffelin  9 , Thomas Verstraeten  1 , Nathalie J Vielle  15 , Anges Yadouleton  2 , Emmanuel Koffi Yovo  2 ; Enable Protocol authorship group
Affiliations

A prospective, multi-site, cohort study to estimate incidence of infection and disease due to Lassa fever virus in West African countries (the Enable Lassa research programme)-Study protocol

Suzanne Penfold et al. PLoS One. .

Erratum in

Abstract

Background: Lassa fever (LF), a haemorrhagic illness caused by the Lassa fever virus (LASV), is endemic in West Africa and causes 5000 fatalities every year. The true prevalence and incidence rates of LF are unknown as infections are often asymptomatic, clinical presentations are varied, and surveillance systems are not robust. The aim of the Enable Lassa research programme is to estimate the incidences of LASV infection and LF disease in five West African countries. The core protocol described here harmonises key study components, such as eligibility criteria, case definitions, outcome measures, and laboratory tests, which will maximise the comparability of data for between-country analyses.

Method: We are conducting a prospective cohort study in Benin, Guinea, Liberia, Nigeria (three sites), and Sierra Leone from 2020 to 2023, with 24 months of follow-up. Each site will assess the incidence of LASV infection, LF disease, or both. When both incidences are assessed the LASV cohort (nmin = 1000 per site) will be drawn from the LF cohort (nmin = 5000 per site). During recruitment participants will complete questionnaires on household composition, socioeconomic status, demographic characteristics, and LF history, and blood samples will be collected to determine IgG LASV serostatus. LF disease cohort participants will be contacted biweekly to identify acute febrile cases, from whom blood samples will be drawn to test for active LASV infection using RT-PCR. Symptom and treatment data will be abstracted from medical records of LF cases. LF survivors will be followed up after four months to assess sequelae, specifically sensorineural hearing loss. LASV infection cohort participants will be asked for a blood sample every six months to assess LASV serostatus (IgG and IgM).

Discussion: Data on LASV infection and LF disease incidence in West Africa from this research programme will determine the feasibility of future Phase IIb or III clinical trials for LF vaccine candidates.

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Conflict of interest statement

The authors have declared that no competing interests exist.

Figures

Fig 1
Fig 1. Study flow diagram.
Fig 2
Fig 2. Map of study sites.
See this image and copyright information in PMC

References

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