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Owuor DC, de Laurent ZR, Nyawanda BO, Emukule GO, Kondor R, Barnes JR, Nokes DJ, Agoti CN, Chaves SS. Genetic and potential antigenic evolution of influenza A(H1N1)pdm09 viruses circulating in Kenya during 2009-2018 influenza seasons. Sci Rep 2023; 13:22342. [PMID: 38102198 PMCID: PMC10724140 DOI: 10.1038/s41598-023-49157-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Accepted: 12/05/2023] [Indexed: 12/17/2023] Open
Abstract
Influenza viruses undergo rapid evolutionary changes, which requires continuous surveillance to monitor for genetic and potential antigenic changes in circulating viruses that can guide control and prevention decision making. We sequenced and phylogenetically analyzed A(H1N1)pdm09 virus genome sequences obtained from specimens collected from hospitalized patients of all ages with or without pneumonia between 2009 and 2018 from seven sentinel surveillance sites across Kenya. We compared these sequences with recommended vaccine strains during the study period to infer genetic and potential antigenic changes in circulating viruses and associations of clinical outcome. We generated and analyzed a total of 383 A(H1N1)pdm09 virus genome sequences. Phylogenetic analyses of HA protein revealed that multiple genetic groups (clades, subclades, and subgroups) of A(H1N1)pdm09 virus circulated in Kenya over the study period; these evolved away from their vaccine strain, forming clades 7 and 6, subclades 6C, 6B, and 6B.1, and subgroups 6B.1A and 6B.1A1 through acquisition of additional substitutions. Several amino acid substitutions among circulating viruses were associated with continued evolution of the viruses, especially in antigenic epitopes and receptor binding sites (RBS) of circulating viruses. Disease severity declined with an increase in age among children aged < 5 years. Our study highlights the necessity of timely genomic surveillance to monitor the evolutionary changes of influenza viruses. Routine influenza surveillance with broad geographic representation and whole genome sequencing capacity to inform on prioritization of antigenic analysis and the severity of circulating strains are critical to improved selection of influenza strains for inclusion in vaccines.
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Affiliation(s)
- D Collins Owuor
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Kilifi, Kenya.
| | - Zaydah R de Laurent
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Gideon O Emukule
- Influenza Division, Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Rebecca Kondor
- Influenza Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - John R Barnes
- Influenza Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - D James Nokes
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Kilifi, Kenya
- School of Life Sciences and Zeeman Institute for Systems Biology and Infectious Disease Epidemiology Research (SBIDER), University of Warwick, Coventry, UK
| | - Charles N Agoti
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI)-Wellcome Trust Research Programme, Kilifi, Kenya
- School of Public Health and Human Sciences, Pwani University, Kilifi, Kenya
| | - Sandra S Chaves
- Influenza Division, Centers for Disease Control and Prevention, Nairobi, Kenya
- Influenza Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, GA, USA
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Andrew MK, Pott H, Staadegaard L, Paget J, Chaves SS, Ortiz JR, McCauley J, Bresee J, Nunes MC, Baumeister E, Raboni SM, Giamberardino HIG, McNeil SA, Gomez D, Zhang T, Vanhems P, Koul PA, Coulibaly D, Otieno NA, Dbaibo G, Almeida MLG, Laguna-Torres VA, Drăgănescu AC, Burtseva E, Sominina A, Danilenko D, Medić S, Diez-Domingo J, Lina B. Age Differences in Comorbidities, Presenting Symptoms, and Outcomes of Influenza Illness Requiring Hospitalization: A Worldwide Perspective From the Global Influenza Hospital Surveillance Network. Open Forum Infect Dis 2023; 10:ofad244. [PMID: 37383245 PMCID: PMC10296081 DOI: 10.1093/ofid/ofad244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 04/26/2023] [Indexed: 06/30/2023] Open
Abstract
Background The Global Influenza Hospital Surveillance Network (GIHSN) was established in 2012 to conduct coordinated worldwide influenza surveillance. In this study, we describe underlying comorbidities, symptoms, and outcomes in patients hospitalized with influenza. Methods Between November 2018 and October 2019, GIHSN included 19 sites in 18 countries using a standardized surveillance protocol. Influenza infection was laboratory-confirmed with reverse-transcription polymerase chain reaction. A multivariate logistic regression model was utilized to analyze the extent to which various risk factors predict severe outcomes. Results Of 16 022 enrolled patients, 21.9% had laboratory-confirmed influenza; 49.2% of influenza cases were A/H1N1pdm09. Fever and cough were the most common symptoms, although they decreased with age (P < .001). Shortness of breath was uncommon among those <50 years but increased with age (P < .001). Middle and older age and history of underlying diabetes or chronic obstructive pulmonary disease were associated with increased odds of death and intensive care unit (ICU) admission, and male sex and influenza vaccination were associated with lower odds. The ICU admissions and mortality occurred across the age spectrum. Conclusions Both virus and host factors contributed to influenza burden. We identified age differences in comorbidities, presenting symptoms, and adverse clinical outcomes among those hospitalized with influenza and benefit from influenza vaccination in protecting against adverse clinical outcomes. The GIHSN provides an ongoing platform for global understanding of hospitalized influenza illness.
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Affiliation(s)
- Melissa K Andrew
- Correspondence: Melissa K. Andrew, MD, PhD, Department of Medicine (Geriatrics), Dalhousie University, 5955 Veterans Memorial Lane, Halifax, NS B3H 2E1, Canada (); Bruno Lina, Laboratoire de Virologie, Institut des Agents Infectieux (IAI), Hospices Civils de Lyon, 103 Grande Rue de la Croix-Rousse, Lyon, 69317 CEDEX 04, France ()
| | - Henrique Pott
- Dalhousie University and Canadian Center for Vaccinology, Halifax, Canada
- Department of Medicine, Universidade Federal de São Carlos, São Carlos, Brazil
| | - Lisa Staadegaard
- Netherlands Institute for Health Care Research (Nivel), Utrecht, Netherlands
| | - John Paget
- Netherlands Institute for Health Care Research (Nivel), Utrecht, Netherlands
| | - Sandra S Chaves
- Foundation for Influenza Epidemiology, Fondation de France, Paris, France
| | - Justin R Ortiz
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - John McCauley
- WHO Collaborating Centre for Reference and Research on Influenza, Crick Institute, London, United Kingdom
| | - Joseph Bresee
- Centre for Vaccine Equity, Task Force for Global Health, Atlanta, Georgia, USA
| | - Marta C Nunes
- South African Medical Research Council, Vaccines & Infectious Diseases Analytics (VIDA) Research Unit, and Department of Science and Technology/National Research Foundation, South African Research Chair Initiative in Vaccine Preventable Diseases, Faculty of Health Sciences University of the Witwatersrand, Johannesburg, South Africa
| | - Elsa Baumeister
- National Reference Laboratory for Viral Respiratory Diseases, Virology Department, INEI-ANLIS, Buenos Aires, Argentina
| | - Sonia Mara Raboni
- Molecular Biology/Microbiology Research Laboratory, Universidade Federal do Paraná, Curitiba, Brazil
| | - Heloisa I G Giamberardino
- Epidemiology, Immunization and Infection Control Department—Hospital Pequeno Principe, Curitiba, Paraná, Brazil
| | - Shelly A McNeil
- Dalhousie University and Canadian Center for Vaccinology, Halifax, Canada
| | - Doris Gomez
- Grupo de Investigación UNIMOL, Facultad de Medicina, Universidad de Cartagena, Cartagena de Indias, Colombia
| | - Tao Zhang
- School of Public Health, Fudan University, Shanghai, China
| | | | | | - Daouda Coulibaly
- Institut National d'Hygiène Publique (INHP), Abidjan, Côte d’Ivoire
| | - Nancy A Otieno
- Kenya Medical Research Institute (KEMRI), Nairobi, Kenya
| | - Ghassan Dbaibo
- Center for Infectious Diseases Research, American University of Beirut, Beirut, Lebanon
| | | | | | | | - Elena Burtseva
- FSBI “N.F. Gamaleya NRCEM” Ministry of Health of the Russian Federation (Federal Research Budgetary Institute “National Research Center of Epidemiology and Microbiology named after honorary academician N.F. Gamaleya), Moscow, Russia
| | - Anna Sominina
- Smorodintsev Research Institute of Influenza, St. Petersburg, Russia
| | - Daria Danilenko
- Smorodintsev Research Institute of Influenza, St. Petersburg, Russia
| | - Snežana Medić
- Institute of Public Health of Vojvodina, Novi Sad, Serbia
- Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia
| | | | - Bruno Lina
- Correspondence: Melissa K. Andrew, MD, PhD, Department of Medicine (Geriatrics), Dalhousie University, 5955 Veterans Memorial Lane, Halifax, NS B3H 2E1, Canada (); Bruno Lina, Laboratoire de Virologie, Institut des Agents Infectieux (IAI), Hospices Civils de Lyon, 103 Grande Rue de la Croix-Rousse, Lyon, 69317 CEDEX 04, France ()
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Epidemiology and Molecular Analyses of Influenza B Viruses in Senegal from 2010 to 2019. Viruses 2022; 14:v14051063. [PMID: 35632804 PMCID: PMC9143141 DOI: 10.3390/v14051063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 05/12/2022] [Accepted: 05/13/2022] [Indexed: 02/04/2023] Open
Abstract
Influenza virus types A and B are responsible for acute viral infections that affect annually 1 billion people, with 290,000 to 650,000 deaths worldwide. In this study, we investigated the circulation of influenza B viruses over a 10-year period (2010–2019). Specimens from patients suspected of influenza infection were collected. Influenza detection was performed following RNA extraction and real-time RT-PCR. Genes coding for hemagglutinin (HA) and neuraminidase (NA) of influenza B viruses were partially sequenced, and phylogenetic analyses were carried out subsequently. During the study period, we received and tested a total of 15,156 specimens. Influenza B virus was detected in 1322 (8.7%) specimens. The mean age of influenza B positive patients was 10.9 years. When compared to reference viruses, HA genes from Senegalese circulating viruses showed deletions in the HA1 region. Phylogenetic analysis highlighted the co-circulation of B/Victoria and B/Yamagata lineage viruses with reassortant viruses. We also noted a clear seasonal pattern of circulation of influenza B viruses in Senegal.
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Owuor DC, de Laurent ZR, Kikwai GK, Mayieka LM, Ochieng M, Müller NF, Otieno NA, Emukule GO, Hunsperger EA, Garten R, Barnes JR, Chaves SS, Nokes DJ, Agoti CN. Characterizing the Countrywide Epidemic Spread of Influenza A(H1N1)pdm09 Virus in Kenya between 2009 and 2018. Viruses 2021; 13:1956. [PMID: 34696386 PMCID: PMC8539974 DOI: 10.3390/v13101956] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 09/13/2021] [Accepted: 09/22/2021] [Indexed: 12/01/2022] Open
Abstract
The spatiotemporal patterns of spread of influenza A(H1N1)pdm09 viruses on a countrywide scale are unclear in many tropical/subtropical regions mainly because spatiotemporally representative sequence data are lacking. We isolated, sequenced, and analyzed 383 A(H1N1)pdm09 viral genomes from hospitalized patients between 2009 and 2018 from seven locations across Kenya. Using these genomes and contemporaneously sampled global sequences, we characterized the spread of the virus in Kenya over several seasons using phylodynamic methods. The transmission dynamics of A(H1N1)pdm09 virus in Kenya were characterized by (i) multiple virus introductions into Kenya over the study period, although only a few of those introductions instigated local seasonal epidemics that then established local transmission clusters, (ii) persistence of transmission clusters over several epidemic seasons across the country, (iii) seasonal fluctuations in effective reproduction number (Re) associated with lower number of infections and seasonal fluctuations in relative genetic diversity after an initial rapid increase during the early pandemic phase, which broadly corresponded to epidemic peaks in the northern and southern hemispheres, (iv) high virus genetic diversity with greater frequency of seasonal fluctuations in 2009-2011 and 2018 and low virus genetic diversity with relatively weaker seasonal fluctuations in 2012-2017, and (v) virus spread across Kenya. Considerable influenza virus diversity circulated within Kenya, including persistent viral lineages that were unique to the country, which may have been capable of dissemination to other continents through a globally migrating virus population. Further knowledge of the viral lineages that circulate within understudied low-to-middle-income tropical and subtropical regions is required to understand the full diversity and global ecology of influenza viruses in humans and to inform vaccination strategies within these regions.
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Affiliation(s)
- D. Collins Owuor
- Wellcome Trust Research Programme, Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI), Kilifi 230-80108, Kenya; (Z.R.d.L.); (D.J.N.); (C.N.A.)
| | - Zaydah R. de Laurent
- Wellcome Trust Research Programme, Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI), Kilifi 230-80108, Kenya; (Z.R.d.L.); (D.J.N.); (C.N.A.)
| | - Gilbert K. Kikwai
- Kenya Medical Research Institute (KEMRI), Nairobi 54840-00200, Kenya; (G.K.K.); (L.M.M.); (M.O.); (N.A.O.)
| | - Lillian M. Mayieka
- Kenya Medical Research Institute (KEMRI), Nairobi 54840-00200, Kenya; (G.K.K.); (L.M.M.); (M.O.); (N.A.O.)
| | - Melvin Ochieng
- Kenya Medical Research Institute (KEMRI), Nairobi 54840-00200, Kenya; (G.K.K.); (L.M.M.); (M.O.); (N.A.O.)
| | - Nicola F. Müller
- Fred Hutchinson Cancer Research Center, Vaccine and Infectious Disease Division, Seattle, WA 98109, USA;
| | - Nancy A. Otieno
- Kenya Medical Research Institute (KEMRI), Nairobi 54840-00200, Kenya; (G.K.K.); (L.M.M.); (M.O.); (N.A.O.)
| | - Gideon O. Emukule
- Centers for Disease Control and Prevention (CDC), Influenza Division, Nairobi 606-00621, Kenya; (G.O.E.); (S.S.C.)
| | - Elizabeth A. Hunsperger
- Centers for Disease Control and Prevention, Division of Global Health Protection, Nairobi 606-00621, Kenya;
- Centers for Disease Control and Prevention, Division of Global Health Protection, Atlanta, GA 30333, USA
| | - Rebecca Garten
- Influenza Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, GA 30333, USA; (R.G.); (J.R.B.)
| | - John R. Barnes
- Influenza Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, GA 30333, USA; (R.G.); (J.R.B.)
| | - Sandra S. Chaves
- Centers for Disease Control and Prevention (CDC), Influenza Division, Nairobi 606-00621, Kenya; (G.O.E.); (S.S.C.)
- Influenza Division, National Center for Immunization and Respiratory Diseases (NCIRD), Centers for Disease Control and Prevention, Atlanta, GA 30333, USA; (R.G.); (J.R.B.)
| | - D. James Nokes
- Wellcome Trust Research Programme, Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI), Kilifi 230-80108, Kenya; (Z.R.d.L.); (D.J.N.); (C.N.A.)
- School of Life Sciences and Zeeman Institute for Systems Biology and Infectious Disease Epidemiology Research (SBIDER), Coventry CV4 7AL, UK
| | - Charles N. Agoti
- Wellcome Trust Research Programme, Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI), Kilifi 230-80108, Kenya; (Z.R.d.L.); (D.J.N.); (C.N.A.)
- School of Public Health and Human Sciences, Pwani University, Kilifi 195-80108, Kenya
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Lagare A, Rajatonirina S, Testa J, Mamadou S. The epidemiology of seasonal influenza after the 2009 influenza pandemic in Africa: a systematic review. Afr Health Sci 2020; 20:1514-1536. [PMID: 34394213 PMCID: PMC8351825 DOI: 10.4314/ahs.v20i4.5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Background Influenza infection is a serious public health problem that causes an estimated 3 to 5 million cases and 250,000 deaths worldwide every year. The epidemiology of influenza is well-documented in high- and middle-income countries, however minimal effort had been made to understand the epidemiology, burden and seasonality of influenza in Africa. This study aims to assess the state of knowledge of seasonal influenza epidemiology in Africa and identify potential data gaps for policy formulation following the 2009 pandemic. Method We reviewed articles from Africa published into four databases namely: MEDLINE (PubMed), Google Scholar, Cochrane Library and Scientific Research Publishing from 2010 to 2019. Results We screened titles and abstracts of 2070 studies of which 311 were selected for full content evaluation and 199 studies were considered. Selected articles varied substantially on the basis of the topics they addressed covering the field of influenza surveillance (n=80); influenza risk factors and co-morbidities (n=15); influenza burden (n=37); influenza vaccination (n=40); influenza and other respiratory pathogens (n=22) and influenza diagnosis (n=5). Conclusion Significant progress has been made since the last pandemic in understanding the influenza epidemiology in Africa. However, efforts still remain for most countries to have sufficient data to allow countries to prioritize strategies for influenza prevention and control.
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Affiliation(s)
- Adamou Lagare
- Centre de Recherche Médicale et Sanitaire (CERMES), Niamey, Niger
| | | | - Jean Testa
- Centre de Recherche Médicale et Sanitaire (CERMES), Niamey, Niger
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Nyasimi FM, Owuor DC, Ngoi JM, Mwihuri AG, Otieno GP, Otieno JR, Githinji G, Nyiro JU, Nokes DJ, Agoti CN. Epidemiological and evolutionary dynamics of influenza B virus in coastal Kenya as revealed by genomic analysis of strains sampled over a single season. Virus Evol 2020; 6:veaa045. [PMID: 33747542 PMCID: PMC7959010 DOI: 10.1093/ve/veaa045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The genomic epidemiology of influenza B virus (IBV) remains understudied in Africa despite significance to design of effective local and global control strategies. We undertook surveillance throughout 2016 in coastal Kenya, recruiting individuals presenting with acute respiratory illness at nine outpatient health facilities (any age) or admitted to the Kilifi County Hospital (<5 years old). Whole genomes were sequenced for a selected 111 positives; 94 (84.7%) of B/Victoria lineage and 17 (15.3%) of B/Yamagata lineage. Inter-lineage reassortment was detected in ten viruses; nine with B/Yamagata backbone but B/Victoria NA and NP segments and one with a B/Victoria backbone but B/Yamagata PB2, PB1, PA, and MP segments. Five phylogenomic clusters were identified among the sequenced viruses; (i), pure B/Victoria clade 1A (n = 93, 83.8%), (ii), reassortant B/Victoria clade 1A (n = 1, 0.9%), (iii), pure B/Yamagata clade 2 (n = 2, 1.8%), (iv), pure B/Yamagata clade 3 (n = 6, 5.4%), and (v), reassortant B/Yamagata clade 3 (n = 9, 8.1%). Using divergence dates and clustering patterns in the presence of global background sequences, we counted up to twenty-nine independent IBV strain introductions into the study area (∼900 km2) in 2016. Local viruses, including the reassortant B/Yamagata strains, clustered closely with viruses from neighbouring Tanzania and Uganda. Our study demonstrated that genomic analysis provides a clearer picture of locally circulating IBV diversity. The high number of IBV introductions highlights the challenge in controlling local influenza epidemics by targeted approaches, for example, sub-population vaccination or patient quarantine. The finding of divergent IBV strains co-circulating within a single season emphasises why broad immunity vaccines are the most ideal for influenza control in Kenya.
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Affiliation(s)
- Festus M Nyasimi
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) – Wellcome Trust Research Programme, P.O. Box 230, Kilifi-80108, Kenya
- Department of Public Health, School of Health and Human Sciences, Pwani University, P.O. Box 195, Kilifi-80108, Kenya
| | - David Collins Owuor
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) – Wellcome Trust Research Programme, P.O. Box 230, Kilifi-80108, Kenya
| | - Joyce M Ngoi
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) – Wellcome Trust Research Programme, P.O. Box 230, Kilifi-80108, Kenya
| | - Alexander G Mwihuri
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) – Wellcome Trust Research Programme, P.O. Box 230, Kilifi-80108, Kenya
| | - Grieven P Otieno
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) – Wellcome Trust Research Programme, P.O. Box 230, Kilifi-80108, Kenya
| | - James R Otieno
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) – Wellcome Trust Research Programme, P.O. Box 230, Kilifi-80108, Kenya
| | - George Githinji
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) – Wellcome Trust Research Programme, P.O. Box 230, Kilifi-80108, Kenya
| | - Joyce U Nyiro
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) – Wellcome Trust Research Programme, P.O. Box 230, Kilifi-80108, Kenya
| | - David James Nokes
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) – Wellcome Trust Research Programme, P.O. Box 230, Kilifi-80108, Kenya
- Department of Public Health, School of Health and Human Sciences, Pwani University, P.O. Box 195, Kilifi-80108, Kenya
- School of Life Sciences and Zeeman Institute for Systems Biology and Infectious Disease Epidemiology Research (SBIDER), University of Warwick, Coventry, CV4, 7AL, UK
| | - Charles N Agoti
- Epidemiology and Demography Department, Kenya Medical Research Institute (KEMRI) – Wellcome Trust Research Programme, P.O. Box 230, Kilifi-80108, Kenya
- Department of Public Health, School of Health and Human Sciences, Pwani University, P.O. Box 195, Kilifi-80108, Kenya
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