1
|
Elsinga J, Sunyoto T, di Stefano L, Giorgetti PF, Kyi HA, Burzio C, Campos Moreno X, Ojide CK, Ajayi N, Ewah R, Ogah EO, Dan-Nwafor C, Ahumibe A, Ochu CL, Olayinka A, Jonckheere S, Chaillet P, van Herp M. Field evaluation of validity and feasibility of Pan-Lassa rapid diagnostic test for Lassa fever in Abakaliki, Nigeria: a prospective diagnostic accuracy study. THE LANCET. INFECTIOUS DISEASES 2024; 24:1037-1044. [PMID: 38734012 DOI: 10.1016/s1473-3099(24)00184-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Revised: 02/29/2024] [Accepted: 03/11/2024] [Indexed: 05/13/2024]
Abstract
BACKGROUND Lassa fever is a viral haemorrhagic fever with few options for diagnosis and treatment; it is also under-researched with knowledge gaps on its epidemiology. A point-of-care bedside test diagnosing Lassa fever, adhering to REASSURED criteria, is not currently available but is urgently needed in west African regions with high Lassa fever burden. We aimed to assess the validity and feasibility of a rapid diagnostic test (RDT) to confirm Lassa fever in people in Nigeria. METHODS We estimated the diagnostic performance of the ReLASV Pan-Lassa RDT (Zalgen Labs, Frederick, MD, USA) as a research-use-only test, compared to RT-PCR as a reference standard, in 217 participants at a federal tertiary hospital in Abakaliki, Nigeria. We recruited participants between Feb 17, 2022, and April 17, 2023. The RDT was performed using capillary blood at the patient bedside and using plasma at the laboratory. The performance of the test, based on REASSURED criteria, was assessed for user friendliness, rapidity and robustness, sensitivity, and specificity. FINDINGS Participants were aged between 0 and 85 years, with a median age of 33·0 years (IQR 22·0-44·3), and 24 participants were younger than 18 years. 107 (50%) participants were women and 109 (50%) were men; one participant had missing sex data. Although the specificity of the Pan-Lassa RDT was high (>90%), sensitivity at bedside using capillary blood was estimated as 4% (95% CI 1-14) at 15 min and 10% (3-22) at 25 min, far below the target of 90%. The laboratory-based RDT using plasma showed better sensitivity (46% [32-61] at 15 min and 50% [36-64] at 25 min) but did not reach the target sensitivity. Among the 52 PCR-positive participants with Lassa fever, positive RDT results were associated with lower cycle threshold values (glycoprotein precursor [GPC] gene mean 30·3 [SD 4·3], Large [L] gene mean 32·3 [3·7] vs GPC gene mean 24·5 [3·9], L gene mean 28·0 [3·6]). Personnel conducting the bedside test procedure reported being hindered by the inconvenient use of full personal protective equipment and long waiting procedures before a result could be read. INTERPRETATION The Pan-Lassa RDT is not currently recommended as a diagnostic or screening tool for suspected Lassa fever cases. Marked improvement in sensitivity and user friendliness is needed for the RDT to be adopted clinically. There remains an urgent need for better Lassa fever diagnostics to promote safety of in-hospital care and better disease outcomes in low-resource settings. FUNDING Médecins Sans Frontières.
Collapse
Affiliation(s)
- Jelte Elsinga
- Luxembourg Operational Research Unit, Médecins Sans Frontières, Luxembourg City, Luxembourg; Department of Medical Microbiology and Infection Prevention, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Temmy Sunyoto
- Luxembourg Operational Research Unit, Médecins Sans Frontières, Luxembourg City, Luxembourg.
| | | | | | | | - Chiara Burzio
- Operational Centre Belgium, Médecins Sans Frontières, Brussels, Belgium
| | | | - Chiedozie K Ojide
- Alex Ekwueme Federal University Teaching Hospital, Federal Ministry of Health, Abakaliki, Nigeria
| | - Nnennaya Ajayi
- Alex Ekwueme Federal University Teaching Hospital, Federal Ministry of Health, Abakaliki, Nigeria
| | - Richard Ewah
- Alex Ekwueme Federal University Teaching Hospital, Federal Ministry of Health, Abakaliki, Nigeria
| | - Emeka O Ogah
- Alex Ekwueme Federal University Teaching Hospital, Federal Ministry of Health, Abakaliki, Nigeria
| | | | - Anthony Ahumibe
- Nigerian Center for Disease Control and Prevention, Abuja, Nigeria
| | | | - Adebola Olayinka
- Nigerian Center for Disease Control and Prevention, Abuja, Nigeria
| | - Sylvie Jonckheere
- Operational Centre Belgium, Médecins Sans Frontières, Brussels, Belgium
| | - Pascale Chaillet
- Operational Centre Belgium, Médecins Sans Frontières, Brussels, Belgium
| | - Michel van Herp
- Operational Centre Belgium, Médecins Sans Frontières, Brussels, Belgium
| |
Collapse
|
2
|
Yimer SA, Booij BB, Tobert G, Hebbeler A, Oloo P, Brangel P, L'Azou Jackson M, Jarman R, Craig D, Avumegah MS, Mandi H, Endy T, Wooden S, Clark C, Bernasconi V, Shurtleff A, Kristiansen PA. Rapid diagnostic test: a critical need for outbreak preparedness and response for high priority pathogens. BMJ Glob Health 2024; 9:e014386. [PMID: 38688565 PMCID: PMC11085978 DOI: 10.1136/bmjgh-2023-014386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 03/30/2024] [Indexed: 05/02/2024] Open
Abstract
Rapid diagnostic tests (RDTs) are critical for preparedness and response against an outbreak or pandemic and have been highlighted in the 100 Days Mission, a global initiative that aims to prepare the world for the next epidemic/pandemic by driving the development of diagnostics, vaccines and therapeutics within 100 days of recognition of a novel Disease X threat.RDTs play a pivotal role in early case identification, surveillance and case management, and are critical for initiating deployment of vaccine and monoclonal antibodies. Currently available RDTs, however, have limited clinical sensitivity and specificity and inadequate validation. The development, validation and implementation of RDTs require adequate and sustained financing from both public and private sources. While the World Health Assembly recently passed a resolution on diagnostic capacity strengthening that urges individual Member States to commit resources towards this, the resolution is not binding and implementation will likely be impeded by limited financial resources and other competing priorities, particularly in low-income countries. Meanwhile, the diagnostic industry has not sufficiently invested in RDT development for high priority pathogens.Currently, vaccine development projects are getting the largest funding support among medical countermeasures. Yet vaccines are insufficient tools in isolation, and pandemic preparedness will be incomplete without parallel investment in diagnostics and therapeutics.The Pandemic Fund, a global financing mechanism recently established for strengthening pandemic prevention, preparedness and response, may be a future avenue for supporting diagnostic development.In this paper, we discuss why RDTs are critical for preparedness and response. We also discuss RDT investment challenges and reflect on the way forward.
Collapse
Affiliation(s)
| | | | - Gwen Tobert
- Coalition for Epidemic Preparedness Innovations, Oslo, Norway
| | - Andrew Hebbeler
- Coalition for Epidemic Preparedness Innovations, Washington, DC, USA
| | - Paul Oloo
- Coalition for Epidemic Preparedness Innovations, London, UK
| | - Polina Brangel
- Coalition for Epidemic Preparedness Innovations, London, UK
| | | | - Richard Jarman
- Coalition for Epidemic Preparedness Innovations, Washington, DC, USA
| | - Danielle Craig
- Coalition for Epidemic Preparedness Innovations, Washington, DC, USA
| | | | - Henshaw Mandi
- Coalition for Epidemic Preparedness Innovations, Oslo, Norway
| | - Timothy Endy
- Coalition for Epidemic Preparedness Innovations, Washington, DC, USA
| | - Stacey Wooden
- Coalition for Epidemic Preparedness Innovations, Washington, DC, USA
| | - Carolyn Clark
- Coalition for Epidemic Preparedness Innovations, Oslo, Norway
| | | | - Amy Shurtleff
- Coalition for Epidemic Preparedness Innovations, Washington, DC, USA
| | | |
Collapse
|
3
|
Viral agents (2nd section). Transfusion 2024; 64 Suppl 1:S19-S207. [PMID: 38394038 DOI: 10.1111/trf.17630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Accepted: 12/02/2023] [Indexed: 02/25/2024]
|
4
|
Arruda LB, Free HB, Simons D, Ansumana R, Elton L, Haider N, Honeyborne I, Asogun D, McHugh TD, Ntoumi F, Zumla A, Kock R. Current sampling and sequencing biases of Lassa mammarenavirus limit inference from phylogeography and molecular epidemiology in Lassa fever endemic regions. PLOS GLOBAL PUBLIC HEALTH 2023; 3:e0002159. [PMID: 37939051 PMCID: PMC10631635 DOI: 10.1371/journal.pgph.0002159] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2023] [Accepted: 10/16/2023] [Indexed: 11/10/2023]
Abstract
Lassa fever (LF) is a potentially lethal viral haemorrhagic infection of humans caused by Lassa mammarenavirus (LASV). It is an important endemic zoonotic disease in West Africa with growing evidence for increasing frequency and sizes of outbreaks. Phylogeographic and molecular epidemiology methods have projected expansion of the Lassa fever endemic zone in the context of future global change. The Natal multimammate mouse (Mastomys natalensis) is the predominant LASV reservoir, with few studies investigating the role of other animal species. To explore host sequencing biases, all LASV nucleotide sequences and associated metadata available on GenBank (n = 2,298) were retrieved. Most data originated from Nigeria (54%), Guinea (20%) and Sierra Leone (14%). Data from non-human hosts (n = 703) were limited and only 69 sequences encompassed complete genes. We found a strong positive correlation between the number of confirmed human cases and sequences at the country level (r = 0.93 (95% Confidence Interval = 0.71-0.98), p < 0.001) but no correlation exists between confirmed cases and the number of available rodent sequences (r = -0.019 (95% C.I. -0.71-0.69), p = 0.96). Spatial modelling of sequencing effort highlighted current biases in locations of available sequences, with increased sequencing effort observed in Southern Guinea and Southern Nigeria. Phylogenetic analyses showed geographic clustering of LASV lineages, suggestive of isolated events of human-to-rodent transmission and the emergence of currently circulating strains of LASV from the year 1498 in Nigeria. Overall, the current study highlights significant geographic limitations in LASV surveillance, particularly, in non-human hosts. Further investigation of the non-human reservoir of LASV, alongside expanded surveillance, are required for precise characterisation of the emergence and dispersal of LASV. Accurate surveillance of LASV circulation in non-human hosts is vital to guide early detection and initiation of public health interventions for future Lassa fever outbreaks.
Collapse
Affiliation(s)
- Liã Bárbara Arruda
- Division of Infection and Immunity, Centre for Clinical Microbiology, University College London, London, United Kingdom
| | - Hayley Beth Free
- The Royal Veterinary College, University of London, Hatfield, United Kingdom
| | - David Simons
- The Royal Veterinary College, University of London, Hatfield, United Kingdom
| | - Rashid Ansumana
- School of Community Health Sciences, Njala University, Bo, Sierra Leone
| | - Linzy Elton
- Division of Infection and Immunity, Centre for Clinical Microbiology, University College London, London, United Kingdom
| | - Najmul Haider
- The Royal Veterinary College, University of London, Hatfield, United Kingdom
| | - Isobella Honeyborne
- Division of Infection and Immunity, Centre for Clinical Microbiology, University College London, London, United Kingdom
| | - Danny Asogun
- Ekpoma and Irrua Specialist Teaching Hospital, Ambrose Alli University, Irrua, Nigeria
| | - Timothy D. McHugh
- Division of Infection and Immunity, Centre for Clinical Microbiology, University College London, London, United Kingdom
| | - Francine Ntoumi
- Fondation Congolaise Pour la Recherche Médicale (FCRM), Brazzaville, Republic of Congo
- Institute for Tropical Medicine, University of Tübingen, Tübingen, Germany
| | - Alimuddin Zumla
- Division of Infection and Immunity, Centre for Clinical Microbiology, University College London, London, United Kingdom
- NIHR Biomedical Research Centre, UCL Hospitals NHS Foundation Trust, London, United Kingdom
| | - Richard Kock
- The Royal Veterinary College, University of London, Hatfield, United Kingdom
| |
Collapse
|
5
|
Kayem ND, Okogbenin S, Okoeguale J, Momoh M, Njoku A, Eifediyi R, Enodiana X, Ngwu H, Irhiogbe W, Ighodalo Y, Olokor T, Odigie G, Castle L, Duraffour S, Oestereich L, Dahal P, Ariana P, Gunther S, Horby P. Seroepidemiology of Lassa virus in pregnant women in Southern Nigeria: A prospective hospital-based cohort study. PLoS Negl Trop Dis 2023; 17:e0011354. [PMID: 37216412 DOI: 10.1371/journal.pntd.0011354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 05/06/2023] [Indexed: 05/24/2023] Open
Abstract
BACKGROUND There is limited epidemiological evidence on Lassa fever in pregnant women with acute gaps on prevalence, infection incidence, and risk factors. Such evidence would facilitate the design of therapeutic and vaccine trials and the design of control programs. Our study sought to address some of these gaps by estimating the seroprevalence and seroconversion risk of Lassa fever in pregnant women. METHODOLOGY/PRINCIPAL FINDINGS We conducted a prospective hospital-based cohort between February and December 2019 in Edo State, Southern Nigeria, enrolling pregnant women at antenatal clinic and following them up at delivery. Samples were evaluated for IgG antibodies against Lassa virus. The study demonstrates a seroprevalence of Lassa IgG antibodies of 49.6% and a seroconversion risk of 20.8%. Seropositivity was strongly correlated with rodent exposure around homes with an attributable risk proportion of 35%. Seroreversion was also seen with a seroreversion risk of 13.4%. CONCLUSIONS/SIGNIFICANCE Our study suggests that 50% of pregnant women were at risk of Lassa infection and that 35.0% of infections might be preventable by avoiding rodent exposure and conditions which facilitate infestation and the risk of human-rodent contact. While the evidence on rodent exposure is subjective and further studies are needed to provide a better understanding of the avenues of human-rodent interaction; public health measures to decrease the risk of rodent infestation and the risk of spill over events may be beneficial. With an estimated seroconversion risk of 20.8%, our study suggests an appreciable risk of contracting Lassa fever during pregnancy and while most of these seroconversions may not be new infections, given the high risk of adverse outcomes in pregnancy, it supports the need for preventative and therapeutic options against Lassa fever in pregnancy. The occurrence of seroreversion in our study suggests that the prevalence obtained in this, and other cohorts may be an underestimate of the actual proportion of women of childbearing age who present at pregnancy with prior LASV exposure. Additionally, the occurrence of both seroconversion and seroreversion in this cohort suggests that these parameters would need to be considered for the development of Lassa vaccine efficacy, effectiveness, and utility models.
Collapse
Affiliation(s)
| | - Sylvanus Okogbenin
- Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Joseph Okoeguale
- Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Mojeed Momoh
- Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Antonia Njoku
- Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Reuben Eifediyi
- Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Xavier Enodiana
- Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Hilary Ngwu
- Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Wilfred Irhiogbe
- Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Yemisi Ighodalo
- Institute of Lassa fever Research and Control, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Thomas Olokor
- Institute of Lassa fever Research and Control, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - George Odigie
- Institute of Lassa fever Research and Control, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Lyndsey Castle
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Sophie Duraffour
- Bernhard-Nocht-Institute for Tropical Medicine, Hamburg, Germany
| | - Lisa Oestereich
- Bernhard-Nocht-Institute for Tropical Medicine, Hamburg, Germany
| | - Prabin Dahal
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Proochista Ariana
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Stephan Gunther
- Bernhard-Nocht-Institute for Tropical Medicine, Hamburg, Germany
| | - Peter Horby
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
6
|
Kayem ND, Okogbenin S, Okoeguale J, Eigbefoh J, Ikheloa J, Eifediyi R, Enodiana X, Olorogbogo OE, Aikpokpo I, Ighodalo Y, Olokor T, Odigie G, Castle L, Duraffour S, Oestereich L, Dahal P, Ariana P, Gunther S, Horby P. Transplacental transfer of Lassa IgG antibodies in pregnant women in Southern Nigeria: A prospective hospital-based cohort study. PLoS Negl Trop Dis 2023; 17:e0011209. [PMID: 37053304 PMCID: PMC10129015 DOI: 10.1371/journal.pntd.0011209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 04/25/2023] [Accepted: 03/01/2023] [Indexed: 04/15/2023] Open
Abstract
BACKGROUND Evidence from previous studies suggest that Lassa fever, a viral haemorrhagic fever endemic to West Africa has high case fatalities, particularly in pregnancy. While there have been remarkable innovations in vaccine development, with some Lassa vaccines undergoing early clinical trials. An understanding of Lassa antibody kinetics and immune responses will support vaccine design and development. However, there is currently no evidence on the antibody kinetics of Lassa (LASV) in pregnancy. Our study sought to estimate the efficiency of transplacental transfer of LASV IgG antibodies from the mother to the child. METHODOLOGY/PRINCIPAL FINDINGS The study made use of data from a prospective hospital-based cohort of pregnant women enrolled at the antenatal clinic and followed up at delivery between February and December 2019. Blood samples from mother-child pairs were evaluated for antibodies against Lassa virus. The study demonstrates a transplacental transfer of LASV IgG of 75.3% [60.0-94.0%], with a significant positive correlation between maternal and cord concentrations and a good level of agreement. The study also suggests that transfer may be more variable in women with 'de novo' antibodies compared to those with pre-existing antibodies. CONCLUSIONS/SIGNIFICANCE The study shows that maternal antibody levels play an important role in determining transfer efficiency of Lassa antibodies to the new-born; and while the evidence is preliminary, the study also suggests that transfer efficiency may be less stable in acute or recent infection, as such timing of vaccination before pregnancy, that is in women of childbearing age may be more appropriate for protection of both pregnant women and their neonates.
Collapse
Affiliation(s)
| | - Sylvanus Okogbenin
- Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Joseph Okoeguale
- Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Joseph Eigbefoh
- Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Joseph Ikheloa
- Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Reuben Eifediyi
- Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Xavier Enodiana
- Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | | | - Isoken Aikpokpo
- Department of Obstetrics and Gynaecology, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Yemisi Ighodalo
- Institute of Lassa fever Research and Control, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Thomas Olokor
- Institute of Lassa fever Research and Control, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - George Odigie
- Institute of Lassa fever Research and Control, Irrua Specialist Teaching Hospital, Irrua, Nigeria
| | - Lyndsey Castle
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Sophie Duraffour
- Bernhard-Nocht-Institute for Tropical Medicine, Hamburg, Germany
| | - Lisa Oestereich
- Bernhard-Nocht-Institute for Tropical Medicine, Hamburg, Germany
| | - Prabin Dahal
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Proochista Ariana
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Stephan Gunther
- Bernhard-Nocht-Institute for Tropical Medicine, Hamburg, Germany
| | - Peter Horby
- Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
7
|
Grant DS, Engel EJ, Roberts Yerkes N, Kanneh L, Koninga J, Gbakie MA, Alhasan F, Kanneh FB, Kanneh IM, Kamara FK, Momoh M, Yillah MS, Foday M, Okoli A, Zeoli A, Weldon C, Bishop CM, Zheng C, Hartnett J, Chao K, Shore K, Melnik LI, Mucci M, Bond NG, Doyle P, Yenni R, Podgorski R, Ficenec SC, Moses L, Shaffer JG, Garry RF, Schieffelin JS. Seroprevalence of anti-Lassa Virus IgG antibodies in three districts of Sierra Leone: A cross-sectional, population-based study. PLoS Negl Trop Dis 2023; 17:e0010938. [PMID: 36758101 PMCID: PMC9946222 DOI: 10.1371/journal.pntd.0010938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 02/22/2023] [Accepted: 11/09/2022] [Indexed: 02/11/2023] Open
Abstract
BACKGROUND Lassa virus (LASV), the cause of the acute viral hemorrhagic illness Lassa fever (LF), is endemic in West Africa. Infections in humans occur mainly after exposure to infected excrement or urine of the rodent-host, Mastomys natalensis. The prevalence of exposure to LASV in Sierra Leone is crudely estimated and largely unknown. This cross-sectional study aimed to establish a baseline point seroprevalence of IgG antibodies to LASV in three administrative districts of Sierra Leone and identify potential risk factors for seropositivity and LASV exposure. METHODOLOGY AND PRINCIPAL FINDINGS Between 2015 and 2018, over 10,642 participants from Kenema, Tonkolili, and Port Loko Districts were enrolled in this cross-sectional study. Previous LASV and LF epidemiological studies support classification of these districts as "endemic," "emerging," and "non-endemic", respectively. Dried blood spot samples were tested for LASV antibodies by ELISA to determine the seropositivity of participants, indicating previous exposure to LASV. Surveys were administered to each participant to assess demographic and environmental factors associated with a higher risk of exposure to LASV. Overall seroprevalence for antibodies to LASV was 16.0%. In Kenema, Port Loko, and Tonkolili Districts, seroprevalences were 20.1%, 14.1%, and 10.6%, respectively. In a multivariate analysis, individuals were more likely to be LASV seropositive if they were living in Kenema District, regardless of sex, age, or occupation. Environmental factors contributed to an increased risk of LASV exposure, including poor housing construction and proximity to bushland, forested areas, and refuse. CONCLUSIONS AND SIGNIFICANCE In this study we determine a baseline LASV seroprevalence in three districts which will inform future epidemiological, ecological, and clinical studies on LF and the LASV in Sierra Leone. The heterogeneity of the distribution of LASV and LF over both space, and time, can make the design of efficacy trials and intervention programs difficult. Having more studies on the prevalence of LASV and identifying potential hyper-endemic areas will greatly increase the awareness of LF and improve targeted control programs related to LASV.
Collapse
Affiliation(s)
- Donald S. Grant
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
- College of Medicine and Allied Health Sciences, University of Sierra Leone, Freetown, Sierra Leone
| | - Emily J. Engel
- Department of Pediatrics, Sections of Pediatric Infectious Diseases, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Nicole Roberts Yerkes
- Department of Pediatrics, Sections of Pediatric Infectious Diseases, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Lansana Kanneh
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - James Koninga
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - Michael A. Gbakie
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - Foday Alhasan
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - Franklyn B. Kanneh
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - Ibrahim Mustapha Kanneh
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - Fatima K. Kamara
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - Mambu Momoh
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
- Eastern Technical University of Sierra Leone, Kenema, Sierra Leone
| | - Mohamed S. Yillah
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - Momoh Foday
- Lassa Fever Program, Kenema Government Hospital, Ministry of Health and Sanitation, Kenema, Sierra Leone
| | - Adaora Okoli
- Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana, United States of America
| | - Ashley Zeoli
- Department of Pediatrics, Sections of Pediatric Infectious Diseases, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Caroline Weldon
- Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana, United States of America
| | - Christopher M. Bishop
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Crystal Zheng
- Department of Internal Medicine, Section of Infectious Diseases, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Jessica Hartnett
- Department of Pediatrics, Sections of Pediatric Infectious Diseases, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Karissa Chao
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Kayla Shore
- Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana, United States of America
| | - Lilia I. Melnik
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Mallory Mucci
- Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana, United States of America
| | - Nell G. Bond
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Philip Doyle
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Rachael Yenni
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Rachel Podgorski
- Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana, United States of America
| | - Samuel C. Ficenec
- Department of Internal Medicine, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Lina Moses
- Department of Tropical Medicine, Tulane University School of Public Health and Tropical Medicine, Tulane University, New Orleans, Louisiana, United States of America
| | - Jeffrey G. Shaffer
- Department of Biostatistics and Data Science, Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana, United States of America
| | - Robert F. Garry
- Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - John S. Schieffelin
- Department of Pediatrics, Sections of Pediatric Infectious Diseases, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| |
Collapse
|
8
|
Merson L, Bourner J, Jalloh S, Erber A, Salam AP, Flahault A, Olliaro PL. Clinical characterization of Lassa fever: A systematic review of clinical reports and research to inform clinical trial design. PLoS Negl Trop Dis 2021; 15:e0009788. [PMID: 34547033 PMCID: PMC8486098 DOI: 10.1371/journal.pntd.0009788] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 10/01/2021] [Accepted: 09/03/2021] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Research is urgently needed to reduce the morbidity and mortality of Lassa fever (LF), including clinical trials to test new therapies and to verify the efficacy and safety of the only current treatment recommendation, ribavirin, which has a weak clinical evidence base. To help establish a basis for the development of an adaptable, standardised clinical trial methodology, we conducted a systematic review to identify the clinical characteristics and outcomes of LF and describe how LF has historically been defined and assessed in the scientific literature. METHODOLOGY Primary clinical studies and reports of patients with suspected and confirmed diagnosis of LF published in the peer-reviewed literature before 15 April 2021 were included. Publications were selected following a two-stage screening of abstracts, then full-texts, by two independent reviewers at each stage. Data were extracted, verified, and summarised using descriptive statistics. RESULTS 147 publications were included, primarily case reports (36%), case series (28%), and cohort studies (20%); only 2 quasi-randomised studies (1%) were found. Data are mostly from Nigeria (52% of individuals, 41% of publications) and Sierra Leone (42% of individuals, 31% of publications). The results corroborate the World Health Organisation characterisation of LF presentation. However, a broader spectrum of presenting symptoms is evident, such as gastrointestinal illness and other nervous system and musculoskeletal disorders that are not commonly included as indicators of LF. The overall case fatality ratio was 30% in laboratory-confirmed cases (1896/6373 reported in 109 publications). CONCLUSION Systematic review is an important tool in the clinical characterisation of diseases with limited publications. The results herein provide a more complete understanding of the spectrum of disease which is relevant to clinical trial design. This review demonstrates the need for coordination across the LF research community to generate harmonised research methods that can contribute to building a strong evidence base for new treatments and foster confidence in their integration into clinical care.
Collapse
Affiliation(s)
- Laura Merson
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- Institute of Global Health, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Josephine Bourner
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | | | - Astrid Erber
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- Department of Epidemiology, Center for Public Health, Medical University of Vienna, Vienna, Austria
| | - Alex Paddy Salam
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Antoine Flahault
- Institute of Global Health, Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Piero L. Olliaro
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
9
|
Yang B, Yang KD. Immunopathogenesis of Different Emerging Viral Infections: Evasion, Fatal Mechanism, and Prevention. Front Immunol 2021; 12:690976. [PMID: 34335596 PMCID: PMC8320726 DOI: 10.3389/fimmu.2021.690976] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Accepted: 06/14/2021] [Indexed: 12/16/2022] Open
Abstract
Different emerging viral infections may emerge in different regions of the world and pose a global pandemic threat with high fatality. Clarification of the immunopathogenesis of different emerging viral infections can provide a plan for the crisis management and prevention of emerging infections. This perspective article describes how an emerging viral infection evolves from microbial mutation, zoonotic and/or vector-borne transmission that progresses to a fatal infection due to overt viremia, tissue-specific cytotropic damage or/and immunopathology. We classified immunopathogenesis of common emerging viral infections into 4 categories: 1) deficient immunity with disseminated viremia (e.g., Ebola); 2) pneumocytotropism with/without later hyperinflammation (e.g., COVID-19); 3) augmented immunopathology (e.g., Hanta); and 4) antibody-dependent enhancement of infection with altered immunity (e.g., Dengue). A practical guide to early blocking of viral evasion, limiting viral load and identifying the fatal mechanism of an emerging viral infection is provided to prevent and reduce the transmission, and to do rapid diagnoses followed by the early treatment of virus neutralization for reduction of morbidity and mortality of an emerging viral infection such as COVID-19.
Collapse
Affiliation(s)
- Betsy Yang
- Department of Medicine, Kaiser Permanente Oakland Medical Center, Oakland, CA, United States
| | - Kuender D. Yang
- DIvision of Medical Research, Mackay Children’s Hospital, Taipei, Taiwan
- Institute of Clinical Medicine, National Yang Ming University, Taipei, Taiwan
- Department of Microbiology & Immunology, National Defense Medical Center, Taipei, Taiwan
| |
Collapse
|
10
|
Akpogheneta O, Dicks S, Grant D, Kanneh Z, Jusu B, Edem-Hotah J, Kanneh L, Alhasan F, Gbakie M, Schieffelin J, Ijaz S, Tedder R, Bower H. Boosting understanding of Lassa Fever virus epidemiology: Field testing a novel assay to identify past Lassa Fever virus infection in blood and oral fluids of survivors and unexposed controls in Sierra Leone. PLoS Negl Trop Dis 2021; 15:e0009255. [PMID: 33788861 PMCID: PMC8041174 DOI: 10.1371/journal.pntd.0009255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 04/12/2021] [Accepted: 02/18/2021] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Despite identification 50 years ago, the true burden of Lassa Fever (LF) across Africa remains undefined for reasons including research focus on hospitalised patients, lack of validated field-feasible tools which reliably identify past infection, and the fact that all assays require blood samples making large-scale surveys difficult. Designated a priority pathogen of epidemic potential requiring urgent research by the World Health Organisation, a better understanding of LF sero-epidemiology is essential to developing and evaluating new interventions including vaccines. We describe the first field testing of a novel species-neutral Double Antigen Binding Assay (DABA) designed to detect antibodies to LF in plasma and oral fluid. METHODOLOGY/PRINCIPAL FINDINGS Paired plasma and oral fluid were collected in Sierra Leone from survivors discharged from Kenema Government Hospital Lassa Fever Unit between 1980 and 2018, and from controls recruited in Freetown in 2019. Epidemiological sensitivity and specificity of the DABA measured against historical diagnosis in survivors and self-declared non-exposed controls was 81.7% (95% CI 70.7%- 89.9%) and 83.3% (72.7%- 91.1%) respectively in plasma, and 71.8% (60.0%- 81.9%) and 83.3% (72.7%- 91.1%) respectively in oral fluid. Antibodies were identified in people infected up to 15 years and, in one case, 40 years previously. Participants found oral fluid collection easy and painless with 80% happy to give an oral fluid sample regularly. CONCLUSIONS/SIGNIFICANCE Given the difficulties of assay validation in a resource-limited setting, including unexpected exposures and diagnostics of varying accuracy, the new assay performed well in both plasma and oral fluid. Sensitivity and specificity are expected to be higher when case/control ascertainment is more definitive and further work is planned to investigate this. Even at the performance levels achieved, the species-neutral DABA has the potential to facilitate the large-scale seroprevalence surveys needed to underpin essential developments in LF control, as well as support zoonotic investigations.
Collapse
Affiliation(s)
- Onome Akpogheneta
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, United Kingdom
| | - Steve Dicks
- Blood Borne Virus Unit, Public Health England, Colindale, United Kingdom
- Microbiology Services, NHS Blood and Transplant, London, United Kingdom
| | - Donald Grant
- Kenema Government Hospital Lassa Fever Unit, Kenema, Sierra Leone
| | - Zainab Kanneh
- Kenema Government Hospital Lassa Fever Unit, Kenema, Sierra Leone
| | - Brima Jusu
- Kenema Government Hospital Lassa Fever Unit, Kenema, Sierra Leone
| | - Joseph Edem-Hotah
- Faculty of Nursing, University of Sierra Leone, Freetown, Sierra Leone
| | - Lansana Kanneh
- Kenema Government Hospital Lassa Fever Unit, Kenema, Sierra Leone
| | - Foday Alhasan
- Kenema Government Hospital Lassa Fever Unit, Kenema, Sierra Leone
| | - Michael Gbakie
- Kenema Government Hospital Lassa Fever Unit, Kenema, Sierra Leone
| | - John Schieffelin
- Sections of Infectious Disease, Tulane University School of Medicine, New Orleans, Louisiana, United States of America
| | - Samreen Ijaz
- Blood Borne Virus Unit, Public Health England, Colindale, United Kingdom
| | - Richard Tedder
- Department of Infectious Disease, Imperial College, London, United Kingdom
| | - Hilary Bower
- UK Public Health Rapid Support Team, London School of Hygiene & Tropical Medicine/Public Health England, London, United Kingdom
| |
Collapse
|
11
|
Auditory function analysis in immunodeficient STAT1 knock-out mice: Considerations for viral infection models. Neurosci Lett 2020; 740:135427. [PMID: 33069812 DOI: 10.1016/j.neulet.2020.135427] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 09/20/2020] [Accepted: 10/07/2020] [Indexed: 11/24/2022]
Abstract
The STAT1 knock-out (KO) mouse is a frequently used transgenic immunodeficient strain to model human viral and bacterial diseases. The Lassa fever model was established in the STAT1 KO mice mimicking phenotypes seen in human patients including deafness in survivors. This model develops hearing loss at high prevalence and is a valuable tool to investigate viral infection-induced hearing loss. However, Lassa virus is a highly contagious and regulated agent requiring the unique logistics of the biosafety level 4 posing limitations for experimental work. Therefore, we did a detailed auditory analysis of the STAT1 KO mice to assess baseline auditory function in preparation for further auditory behavioral studies. Auditory brainstem response and distortion product otoacoustic emission tests were performed on males and females of the STAT1 KO mice and was compared to 129S6/SvEv wild type (WT) mice. The male WT mice had the best auditory performance and the female WT mice had the worst hearing performance. The male and female STAT1 KO mice had similar auditory performance to each other, which was intermediate between WT males and females. We conclude that both male and female STAT1 KO mice are suitable for studying viral infection-induced hearing loss.
Collapse
|
12
|
Kenmoe S, Tchatchouang S, Ebogo-Belobo JT, Ka'e AC, Mahamat G, Guiamdjo Simo RE, Bowo-Ngandji A, Demeni Emoh CP, Che E, Tchami Ngongang D, Amougou-Atsama M, Nzukui ND, Mbongue Mikangue CA, Mbaga DS, Kenfack S, Kingue Bebey SR, Amvongo Adjia N, Efietngab AN, Tazokong HR, Modiyinji AF, Kengne-Nde C, Sadeuh-Mba SA, Njouom R. Systematic review and meta-analysis of the epidemiology of Lassa virus in humans, rodents and other mammals in sub-Saharan Africa. PLoS Negl Trop Dis 2020; 14:e0008589. [PMID: 32845889 PMCID: PMC7478710 DOI: 10.1371/journal.pntd.0008589] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 09/08/2020] [Accepted: 07/13/2020] [Indexed: 12/27/2022] Open
Abstract
Accurate data on the Lassa virus (LASV) human case fatality rate (CFR) and the prevalence of LASV in humans, rodents and other mammals are needed for better planning of actions that will ultimately reduce the burden of LASV infection in sub-Saharan Africa. In this systematic review with meta-analysis, we searched PubMed, Scopus, Africa Journal Online, and African Index Medicus from 1969 to 2020 to obtain studies that reported enough data to calculate LASV infection CFR or prevalence. Study selection, data extraction, and risk of bias assessment were conducted independently. We extracted all measures of current, recent, and past infections with LASV. Prevalence and CFR estimates were pooled using a random-effect meta-analysis. Factors associated with CFR, prevalence, and sources of between-study heterogeneity were determined using subgroup and metaregression analyses. This review was registered with PROSPERO, CRD42020166465. We initially identified 1,399 records and finally retained 109 reports that contributed to 291 prevalence records from 25 countries. The overall CFR was 29.7% (22.3-37.5) in humans. Pooled prevalence of LASV infection was 8.7% (95% confidence interval: 6.8-10.8) in humans, 3.2% (1.9-4.6) in rodents, and 0.7% (0.0-2.3) in other mammals. Subgroup and metaregression analyses revealed a substantial statistical heterogeneity explained by higher prevalence in tissue organs, in case-control, in hospital outbreak, and surveys, in retrospective studies, in urban and hospital setting, in hospitalized patients, and in West African countries. This study suggests that LASV infections is an important cause of death in humans and that LASV are common in humans, rodents and other mammals in sub-Saharan Africa. These estimates highlight disparities between sub-regions, and population risk profiles. Western Africa, and specific key populations were identified as having higher LASV CFR and prevalence, hence, deserving more attention for cost-effective preventive interventions.
Collapse
Affiliation(s)
- Sebastien Kenmoe
- Department of Virology, Centre Pasteur of Cameroon, Yaoundé, Cameroon
| | | | - Jean Thierry Ebogo-Belobo
- Medical Research Centre, Institut of Medical Research and Medicinal Plants Studies, Yaoundé, Cameroon
| | - Aude Christelle Ka'e
- Virology Department, Chantal Biya International Reference Centre, Yaoundé, Cameroon
| | - Gadji Mahamat
- Department of Microbiology, Faculty of Science, The University of Yaounde I, Yaoundé, Cameroon
| | | | - Arnol Bowo-Ngandji
- Department of Microbiology, Faculty of Science, The University of Yaounde I, Yaoundé, Cameroon
| | | | - Emmanuel Che
- Vaccinology and Biobank, Chantal Biya International Reference Centre, Yaounde, Cameroon
| | - Dimitri Tchami Ngongang
- Department of Microbiology, Faculty of Science, The University of Yaounde I, Yaoundé, Cameroon
| | - Marie Amougou-Atsama
- Department of Virology, Centre Pasteur of Cameroon, Yaoundé, Cameroon
- Medical Research Centre, Institut of Medical Research and Medicinal Plants Studies, Yaoundé, Cameroon
| | - Nathalie Diane Nzukui
- School of Health Sciences-Catholic University of Central Africa, Department of Medical Microbiology, Yaoundé, Cameroon
| | | | - Donatien Serge Mbaga
- Department of Microbiology, Faculty of Science, The University of Yaounde I, Yaoundé, Cameroon
| | - Sorel Kenfack
- Department of Microbiology, Faculty of Science, The University of Yaounde I, Yaoundé, Cameroon
| | | | - Nathalie Amvongo Adjia
- Medical Research Centre, Institut of Medical Research and Medicinal Plants Studies, Yaoundé, Cameroon
| | - Atembeh Noura Efietngab
- Medical Research Centre, Institut of Medical Research and Medicinal Plants Studies, Yaoundé, Cameroon
| | - Hervé Raoul Tazokong
- Department of Microbiology, Faculty of Science, The University of Yaounde I, Yaoundé, Cameroon
| | - Abdou Fatawou Modiyinji
- Department of Virology, Centre Pasteur of Cameroon, Yaoundé, Cameroon
- Department of Animals Biology and Physiology, Faculty of Science, The University of Yaoundé I, Yaoundé, Cameroon
| | - Cyprien Kengne-Nde
- Epidemiological Surveillance, Evaluation and Research Unit, National AIDS Control Committee, Yaoundé, Cameroon
| | | | - Richard Njouom
- Department of Virology, Centre Pasteur of Cameroon, Yaoundé, Cameroon
| |
Collapse
|
13
|
Klitting R, Mehta SB, Oguzie JU, Oluniyi PE, Pauthner MG, Siddle KJ, Andersen KG, Happi CT, Sabeti PC. Lassa Virus Genetics. Curr Top Microbiol Immunol 2020. [PMID: 32418034 DOI: 10.1007/82_2020_212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
In a pattern repeated across a range of ecological niches, arenaviruses have evolved a compact four-gene genome to orchestrate a complex life cycle in a narrow range of susceptible hosts. A number of mammalian arenaviruses cross-infect humans, often causing a life-threatening viral hemorrhagic fever. Among this group of geographically bound zoonoses, Lassa virus has evolved a unique niche that leads to significant and sustained human morbidity and mortality. As a biosafety level 4 pathogen, direct study of the pathogenesis of Lassa virus is limited by the sparse availability, high operating costs, and technical restrictions of the high-level biocontainment laboratories required for safe experimentation. In this chapter, we introduce the relationship between genome structure and the life cycle of Lassa virus and outline reverse genetic approaches used to probe and describe functional elements of the Lassa virus genome. We then review the tools used to obtain viral genomic sequences used for phylogeny and molecular diagnostics, before shifting to a population perspective to assess the contributions of phylogenetic analysis in understanding the evolution and ecology of Lassa virus in West Africa. We finally consider the future outlook and clinical applications for genetic study of Lassa virus.
Collapse
Affiliation(s)
- Raphaëlle Klitting
- Department of Immunology and Microbiology, The Scripps Research Institute , La Jolla, CA, USA
| | - Samar B Mehta
- Broad Institute of MIT and Harvard, Cambridge, MA, USA
- Division of Infectious Diseases, Beth Israel Deaconess Medical Center, Boston, MA, USA
| | - Judith U Oguzie
- African Center of Excellence for Genomics of Infectious Diseases (ACEGID), Redeemer's University, Ede, Osun State, Nigeria
- Department of Biological Sciences, Faculty of Natural Sciences, Redeemers University, Ede, Osun State, Nigeria
| | - Paul E Oluniyi
- African Center of Excellence for Genomics of Infectious Diseases (ACEGID), Redeemer's University, Ede, Osun State, Nigeria
- Department of Biological Sciences, Faculty of Natural Sciences, Redeemers University, Ede, Osun State, Nigeria
| | - Matthias G Pauthner
- Department of Immunology and Microbiology, The Scripps Research Institute , La Jolla, CA, USA
| | | | - Kristian G Andersen
- Department of Immunology and Microbiology, The Scripps Research Institute , La Jolla, CA, USA.
| | - Christian T Happi
- African Center of Excellence for Genomics of Infectious Diseases (ACEGID), Redeemer's University, Ede, Osun State, Nigeria
- Department of Biological Sciences, Faculty of Natural Sciences, Redeemers University, Ede, Osun State, Nigeria
| | - Pardis C Sabeti
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Center for Systems Biology, Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, USA.
- Department of Immunology and Infectious Diseases, Harvard TH Chan School of Public Health, Boston, MA, USA.
- Howard Hughes Medical Institute, Chevy Chase, MD, USA.
| |
Collapse
|