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Otiende M, Nyaguara A, Bottomley C, Walumbe D, Mochamah G, Amadi D, Nyundo C, Kagucia EW, Etyang AO, Adetifa IMO, Brand SPC, Maitha E, Chondo E, Nzomo E, Aman R, Mwangangi M, Amoth P, Kasera K, Ng'ang'a W, Barasa E, Tsofa B, Mwangangi J, Bejon P, Agweyu A, Williams TN, Scott JAG. Impact of COVID-19 on mortality in coastal Kenya: a longitudinal open cohort study. Nat Commun 2023; 14:6879. [PMID: 37898630 PMCID: PMC10613220 DOI: 10.1038/s41467-023-42615-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Accepted: 10/17/2023] [Indexed: 10/30/2023] Open
Abstract
The mortality impact of COVID-19 in Africa remains controversial because most countries lack vital registration. We analysed excess mortality in Kilifi Health and Demographic Surveillance System, Kenya, using 9 years of baseline data. SARS-CoV-2 seroprevalence studies suggest most adults here were infected before May 2022. During 5 waves of COVID-19 (April 2020-May 2022) an overall excess mortality of 4.8% (95% PI 1.2%, 9.4%) concealed a significant excess (11.6%, 95% PI 5.9%, 18.9%) among older adults ( ≥ 65 years) and a deficit among children aged 1-14 years (-7.7%, 95% PI -20.9%, 6.9%). The excess mortality rate for January 2020-December 2021, age-standardised to the Kenyan population, was 27.4/100,000 person-years (95% CI 23.2-31.6). In Coastal Kenya, excess mortality during the pandemic was substantially lower than in most high-income countries but the significant excess mortality in older adults emphasizes the value of achieving high vaccine coverage in this risk group.
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Affiliation(s)
- M Otiende
- KEMRI-Wellcome Research Trust Programme, PO Box 230, Kilifi, 80108, Kenya.
| | - A Nyaguara
- KEMRI-Wellcome Research Trust Programme, PO Box 230, Kilifi, 80108, Kenya
| | - C Bottomley
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, Keppel Street London, London, WC1E 7HT, UK
| | - D Walumbe
- KEMRI-Wellcome Research Trust Programme, PO Box 230, Kilifi, 80108, Kenya
| | - G Mochamah
- KEMRI-Wellcome Research Trust Programme, PO Box 230, Kilifi, 80108, Kenya
| | - D Amadi
- KEMRI-Wellcome Research Trust Programme, PO Box 230, Kilifi, 80108, Kenya
| | - C Nyundo
- KEMRI-Wellcome Research Trust Programme, PO Box 230, Kilifi, 80108, Kenya
| | - E W Kagucia
- KEMRI-Wellcome Research Trust Programme, PO Box 230, Kilifi, 80108, Kenya
| | - A O Etyang
- KEMRI-Wellcome Research Trust Programme, PO Box 230, Kilifi, 80108, Kenya
| | - I M O Adetifa
- KEMRI-Wellcome Research Trust Programme, PO Box 230, Kilifi, 80108, Kenya
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, Keppel Street London, London, WC1E 7HT, UK
| | - S P C Brand
- The Zeeman Institute for Systems Biology and Infectious Disease Epidemiology Research, University of Warwick, Coventry, CV4 7AL, UK
| | - E Maitha
- Department of Health, Kilifi County, Kilifi, Kenya
| | - E Chondo
- Department of Health, Kilifi County, Kilifi, Kenya
| | - E Nzomo
- Kilifi County Hospital, Kilifi, Kenya
| | - R Aman
- Ministry of Health, Government of Kenya; Afya House, Cathedral Road, Nairobi, Kenya
| | - M Mwangangi
- Ministry of Health, Government of Kenya; Afya House, Cathedral Road, Nairobi, Kenya
| | - P Amoth
- Ministry of Health, Government of Kenya; Afya House, Cathedral Road, Nairobi, Kenya
| | - K Kasera
- Ministry of Health, Government of Kenya; Afya House, Cathedral Road, Nairobi, Kenya
| | - W Ng'ang'a
- Presidential Policy and Strategy Unit, The Presidency, Government of Kenya, Nairobi, Kenya
| | - E Barasa
- KEMRI-Wellcome Research Trust Programme, PO Box 230, Kilifi, 80108, Kenya
| | - B Tsofa
- KEMRI-Wellcome Research Trust Programme, PO Box 230, Kilifi, 80108, Kenya
| | - J Mwangangi
- KEMRI-Wellcome Research Trust Programme, PO Box 230, Kilifi, 80108, Kenya
| | - P Bejon
- KEMRI-Wellcome Research Trust Programme, PO Box 230, Kilifi, 80108, Kenya
- Nuffield Department of Clinical Medicine, University of Oxford, Old Road Campus, Oxford, OX3 7BN, UK
| | - A Agweyu
- KEMRI-Wellcome Research Trust Programme, PO Box 230, Kilifi, 80108, Kenya
| | - T N Williams
- KEMRI-Wellcome Research Trust Programme, PO Box 230, Kilifi, 80108, Kenya
- Institute for Global Health Innovation, Imperial College, London, SW72AS, UK
| | - J A G Scott
- KEMRI-Wellcome Research Trust Programme, PO Box 230, Kilifi, 80108, Kenya
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, Keppel Street London, London, WC1E 7HT, UK
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Kagucia EW, Ziraba AK, Nyagwange J, Kutima B, Kimani M, Akech D, Ng'oda M, Sigilai A, Mugo D, Karanja H, Gitonga J, Karani A, Toroitich M, Karia B, Otiende M, Njeri A, Aman R, Amoth P, Mwangangi M, Kasera K, Ng'ang'a W, Voller S, Ochola‐Oyier LI, Bottomley C, Nyaguara A, Munywoki PK, Bigogo G, Maitha E, Uyoga S, Gallagher KE, Etyang AO, Barasa E, Mwangangi J, Bejon P, Adetifa IMO, Warimwe GM, Scott JAG, Agweyu A. SARS-CoV-2 seroprevalence and implications for population immunity: Evidence from two Health and Demographic Surveillance System sites in Kenya, February-December 2022. Influenza Other Respir Viruses 2023; 17:e13173. [PMID: 37752065 PMCID: PMC10522478 DOI: 10.1111/irv.13173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 06/19/2023] [Accepted: 06/28/2023] [Indexed: 09/28/2023] Open
Abstract
BACKGROUND We sought to estimate SARS-CoV-2 antibody seroprevalence within representative samples of the Kenyan population during the third year of the COVID-19 pandemic and the second year of COVID-19 vaccine use. METHODS We conducted cross-sectional serosurveys among randomly selected, age-stratified samples of Health and Demographic Surveillance System (HDSS) residents in Kilifi and Nairobi. Anti-spike (anti-S) immunoglobulin G (IgG) serostatus was measured using a validated in-house ELISA and antibody concentrations estimated with reference to the WHO International Standard for anti-SARS-CoV-2 immunoglobulin. RESULTS HDSS residents were sampled in February-June 2022 (Kilifi HDSS N = 852; Nairobi Urban HDSS N = 851) and in August-December 2022 (N = 850 for both sites). Population-weighted coverage for ≥1 doses of COVID-19 vaccine were 11.1% (9.1-13.2%) among Kilifi HDSS residents by November 2022 and 34.2% (30.7-37.6%) among Nairobi Urban HDSS residents by December 2022. Population-weighted anti-S IgG seroprevalence among Kilifi HDSS residents increased from 69.1% (65.8-72.3%) by May 2022 to 77.4% (74.4-80.2%) by November 2022. Within the Nairobi Urban HDSS, seroprevalence by June 2022 was 88.5% (86.1-90.6%), comparable with seroprevalence by December 2022 (92.2%; 90.2-93.9%). For both surveys, seroprevalence was significantly lower among Kilifi HDSS residents than among Nairobi Urban HDSS residents, as were antibody concentrations (p < 0.001). CONCLUSION More than 70% of Kilifi residents and 90% of Nairobi residents were seropositive for anti-S IgG by the end of 2022. There is a potential immunity gap in rural Kenya; implementation of interventions to improve COVID-19 vaccine uptake among sub-groups at increased risk of severe COVID-19 in rural settings is recommended.
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Affiliation(s)
| | | | | | | | | | - Donald Akech
- KEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
| | - Maurine Ng'oda
- African Population and Health Research CenterNairobiKenya
| | | | - Daisy Mugo
- KEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
| | | | - John Gitonga
- KEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
| | | | | | | | - Mark Otiende
- KEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
| | - Anne Njeri
- African Population and Health Research CenterNairobiKenya
| | | | | | | | | | - Wangari Ng'ang'a
- Presidential Policy and Strategy UnitThe Presidency, Government of KenyaNairobiKenya
| | - Shirine Voller
- KEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
- London School of Hygiene and Tropical MedicineLondonUK
| | | | | | | | - Patrick K. Munywoki
- Division for Global Health ProtectionUS Centers of Disease Control and Prevention, Center for Global HealthNairobiKenya
| | | | | | - Sophie Uyoga
- KEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
| | - Katherine E. Gallagher
- KEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
- London School of Hygiene and Tropical MedicineLondonUK
| | | | | | | | - Philip Bejon
- KEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of MedicineOxford UniversityOxfordUK
| | - Ifedayo M. O. Adetifa
- KEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
- London School of Hygiene and Tropical MedicineLondonUK
| | - George M. Warimwe
- KEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of MedicineOxford UniversityOxfordUK
| | - J. Anthony G. Scott
- KEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
- London School of Hygiene and Tropical MedicineLondonUK
| | - Ambrose Agweyu
- KEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
- London School of Hygiene and Tropical MedicineLondonUK
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3
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Cichowitz C, Kisigo G, Ruselu G, Wajanga B, Desderius B, Etyang AO, Kapiga S, Peck R. Translating Ethics into Practice: Providing Long-Term Cardiometabolic and Cardiovascular Disease Care for Research Participants in Africa. Glob Heart 2023; 18:34. [PMID: 37334399 PMCID: PMC10275192 DOI: 10.5334/gh.1206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 05/02/2023] [Indexed: 06/20/2023] Open
Affiliation(s)
- Cody Cichowitz
- Division of Cardiology, University of California San Francisco, San Francisco, CA, USA
- Department of Medicine, Center for Global Health, Massachusetts General Hospital, Boston, MA, USA
- Mwanza Intervention Trials Unit, National Institute for Medical Research, Mwanza, Tanzania
- Bugando Medical Centre, Mwanza, Tanzania
| | - Godfrey Kisigo
- Mwanza Intervention Trials Unit, National Institute for Medical Research, Mwanza, Tanzania
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
| | - Grace Ruselu
- Mwanza Intervention Trials Unit, National Institute for Medical Research, Mwanza, Tanzania
- Bugando Medical Centre, Mwanza, Tanzania
| | | | | | | | - Saidi Kapiga
- Mwanza Intervention Trials Unit, National Institute for Medical Research, Mwanza, Tanzania
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
| | - Robert Peck
- Mwanza Intervention Trials Unit, National Institute for Medical Research, Mwanza, Tanzania
- Bugando Medical Centre, Mwanza, Tanzania
- Center for Global Health, Weill Cornell Medicine, New York, USA
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Downs LO, Campbell C, Yonga P, Githinji G, Ansari MA, Matthews PC, Etyang AO. A systematic review of Hepatitis B virus (HBV) prevalence and genotypes in Kenya: Data to inform clinical care and health policy. PLOS Glob Public Health 2023; 3:e0001165. [PMID: 36963057 PMCID: PMC10022289 DOI: 10.1371/journal.pgph.0001165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 11/28/2022] [Indexed: 02/04/2023]
Abstract
The aim of this systematic review and meta-analysis is to evaluate available prevalence and viral sequencing data representing chronic hepatitis B (CHB) infection in Kenya. More than 20% of the global disease burden from CHB is in Africa, however there is minimal high quality seroprevalence data from individual countries and little viral sequencing data available to represent the continent. We undertook a systematic review of the prevalence and genetic data available for hepatitis B virus (HBV) in Kenya using the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) 2020 checklist. We identified 23 studies reporting HBV prevalence and 8 studies that included HBV genetic data published in English between January 2000 and December 2021. We assessed study quality using the Joanna Briggs Institute critical appraisal checklist. Due to study heterogeneity, we divided the studies to represent low, moderate, high and very high-risk for HBV infection, identifying 8, 7, 5 and 3 studies in these groups, respectively. We calculated pooled HBV prevalence within each group and evaluated available sequencing data. Pooled HBV prevalence was 3.4% (95% CI 2.7-4.2%), 6.1% (95% CI 5.1-7.4%), 6.2% (95% CI 4.64-8.2) and 29.2% (95% CI 12.2-55.1), respectively. Study quality was overall low; only three studies detailed sample size calculation and 17/23 studies were cross sectional. Eight studies included genetic information on HBV, with two undertaking whole genome sequencing. Genotype A accounted for 92% of infections. Other genotypes included genotype D (6%), D/E recombinants (1%) or mixed populations (1%). Drug resistance mutations were reported by two studies. There is an urgent need for more high quality seroprevalence and genetic data to represent HBV in Kenya to underpin improved HBV screening, treatment and prevention in order to support progress towards elimination targets.
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Affiliation(s)
- Louise O Downs
- Nuffield Department of Medicine, Medawar Building for Pathogen Research, University of Oxford, Oxford, United Kingdom
- Department of Infectious Diseases and Microbiology, John Radcliffe Hospital, Headley Way, Oxford, United Kingdom
| | - Cori Campbell
- Nuffield Department of Medicine, Medawar Building for Pathogen Research, University of Oxford, Oxford, United Kingdom
| | - Paul Yonga
- CA Medlynks Clinic and Laboratory, Nairobi, and Fountain Projects and Research Office, Fountain Health Care Hospital, Eldoret, Kenya
| | - George Githinji
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Department of Biochemistry and Biotechnology, Pwani University, Kilifi, Kenya
| | - M Azim Ansari
- Nuffield Department of Medicine, Medawar Building for Pathogen Research, University of Oxford, Oxford, United Kingdom
| | - Philippa C Matthews
- Nuffield Department of Medicine, Medawar Building for Pathogen Research, University of Oxford, Oxford, United Kingdom
- The Francis Crick Institute, London, United Kingdom
- Division of Infection and Immunity, University College London, London, London, United Kingdom
- Department of Infectious Diseases, University College London Hospital, London, London, United Kingdom
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5
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Etyang AO, Adetifa I, Omore R, Misore T, Ziraba AK, Ng’oda MA, Gitau E, Gitonga J, Mugo D, Kutima B, Karanja H, Toroitich M, Nyagwange J, Tuju J, Wanjiku P, Aman R, Amoth P, Mwangangi M, Kasera K, Ng’ang’a W, Akech D, Sigilai A, Karia B, Karani A, Voller S, Agoti CN, Ochola-Oyier LI, Otiende M, Bottomley C, Nyaguara A, Uyoga S, Gallagher K, Kagucia EW, Onyango D, Tsofa B, Mwangangi J, Maitha E, Barasa E, Bejon P, Warimwe GM, Scott JAG, Agweyu A. SARS-CoV-2 seroprevalence in three Kenyan health and demographic surveillance sites, December 2020-May 2021. PLOS Glob Public Health 2022; 2:e0000883. [PMID: 36962821 PMCID: PMC10021917 DOI: 10.1371/journal.pgph.0000883] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 07/12/2022] [Indexed: 11/19/2022]
Abstract
BACKGROUND Most of the studies that have informed the public health response to the COVID-19 pandemic in Kenya have relied on samples that are not representative of the general population. We conducted population-based serosurveys at three Health and Demographic Surveillance Systems (HDSSs) to determine the cumulative incidence of infection with SARS-CoV-2. METHODS We selected random age-stratified population-based samples at HDSSs in Kisumu, Nairobi and Kilifi, in Kenya. Blood samples were collected from participants between 01 Dec 2020 and 27 May 2021. No participant had received a COVID-19 vaccine. We tested for IgG antibodies to SARS-CoV-2 spike protein using ELISA. Locally-validated assay sensitivity and specificity were 93% (95% CI 88-96%) and 99% (95% CI 98-99.5%), respectively. We adjusted prevalence estimates using classical methods and Bayesian modelling to account for the sampling scheme and assay performance. RESULTS We recruited 2,559 individuals from the three HDSS sites, median age (IQR) 27 (10-78) years and 52% were female. Seroprevalence at all three sites rose steadily during the study period. In Kisumu, Nairobi and Kilifi, seroprevalences (95% CI) at the beginning of the study were 36.0% (28.2-44.4%), 32.4% (23.1-42.4%), and 14.5% (9.1-21%), and respectively; at the end they were 42.0% (34.7-50.0%), 50.2% (39.7-61.1%), and 24.7% (17.5-32.6%), respectively. Seroprevalence was substantially lower among children (<16 years) than among adults at all three sites (p≤0.001). CONCLUSION By May 2021 in three broadly representative populations of unvaccinated individuals in Kenya, seroprevalence of anti-SARS-CoV-2 IgG was 25-50%. There was wide variation in cumulative incidence by location and age.
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Affiliation(s)
| | - Ifedayo Adetifa
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Richard Omore
- Kenya Medical Research Institute Centre for Global Health Research, Kisumu, Kenya
| | - Thomas Misore
- Kenya Medical Research Institute Centre for Global Health Research, Kisumu, Kenya
| | | | | | - Evelyn Gitau
- African Population and Health Research Center, Nairobi, Kenya
| | - John Gitonga
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Daisy Mugo
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Henry Karanja
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | | | - James Tuju
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | | | | | | | | | - Wangari Ng’ang’a
- Presidential Policy and Strategy Unit, The Presidency, Government of Kenya, Nairobi, Kenya
| | - Donald Akech
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | | | - Angela Karani
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Shirine Voller
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | | | - Mark Otiende
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Amek Nyaguara
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Sophie Uyoga
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | | | | | | | | | | | - Edwine Barasa
- Health Economics Research Unit, KEMRI-Wellcome Trust Research Programme, Nairobi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Oxford University, Oxford, United Kingdom
| | - Philip Bejon
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Oxford University, Oxford, United Kingdom
| | - George M. Warimwe
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Oxford University, Oxford, United Kingdom
| | - J. Anthony G. Scott
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- London School of Hygiene and Tropical Medicine, London, United Kingdom
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6
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Yan LD, Matuja SS, Pain KJ, McNairy ML, Etyang AO, Peck RN. Emerging Viral Infections, Hypertension, and Cardiovascular Disease in Sub-Saharan Africa: A Narrative Review. Hypertension 2022; 79:898-905. [PMID: 35272495 PMCID: PMC9010372 DOI: 10.1161/hypertensionaha.121.17949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Sub-Saharan Africa (SSA) has the highest age-adjusted burden of hypertension and cardiovascular disease (CVD). SSA also experiences many viral infections due to unique environmental and societal factors. The purpose of this narrative review is to examine evidence around how hypertension, CVD, and emerging viral infections interact in SSA. METHODS In September 2021, we conducted a search in MEDLINE, Embase, and Scopus, limited to English language studies published since 1990, and found a total of 1169 articles. Forty-seven original studies were included, with 32 on COVID-19 and 15 on other emerging viruses. RESULTS Seven articles, including those with the largest sample size and most robust study design, found an association between preexisting hypertension or CVD and COVID-19 severity or death. Ten smaller studies found no association, and 17 did not calculate statistics to compare groups. Two studies assessed the impact of COVID-19 on incident CVD, with one finding an increase in stroke admissions. For other emerging viruses, 3 studies did not find an association between preexisting hypertension or CVD on West Nile and Lassa fever mortality. Twelve studies examined other emerging viral infections and incident CVD, with 4 finding no association and 8 not calculating statistics. CONCLUSIONS Growing evidence from COVID-19 suggests viruses, hypertension, and CVD interact on multiple levels in SSA, but research gaps remain especially for other emerging viral infections. SSA can and must play a leading role in the study and control of emerging viral infections, with expansion of research and public health infrastructure to address these interactions.
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Affiliation(s)
- Lily D Yan
- Center for Global Health and Division of General Internal Medicine, Weill Cornell Medicine, New York, NY, USA
| | - Sarah S Matuja
- Department of Medicine, Weill Bugando School of Medicine, Mwanza, Tanzania
| | - Kevin J Pain
- Samuel J. Wood Library and C. V. Starr Biomedical Information Center, Weill Cornell Medicine, New York, NY, USA
| | - Margaret L McNairy
- Center for Global Health and Division of General Internal Medicine, Weill Cornell Medicine, New York, NY, USA
| | | | - Robert N Peck
- Center for Global Health and Division of General Internal Medicine, Weill Cornell Medicine, New York, NY, USA
- Department of Medicine, Weill Bugando School of Medicine, Mwanza, Tanzania
- Mwanza Interventions Trial Unit, Mwanza, Tanzania
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7
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Etyang AO, Lucinde R, Karanja H, Kalu C, Mugo D, Nyagwange J, Gitonga J, Tuju J, Wanjiku P, Karani A, Mutua S, Maroko H, Nzomo E, Maitha E, Kamuri E, Kaugiria T, Weru J, Ochola LB, Kilimo N, Charo S, Emukule N, Moracha W, Mukabi D, Okuku R, Ogutu M, Angujo B, Otiende M, Bottomley C, Otieno E, Ndwiga L, Nyaguara A, Voller S, Agoti CN, Nokes DJ, Ochola-Oyier LI, Aman R, Amoth P, Mwangangi M, Kasera K, Ng’ang’a W, Adetifa IMO, Wangeci Kagucia E, Gallagher K, Uyoga S, Tsofa B, Barasa E, Bejon P, Scott JAG, Agweyu A, Warimwe GM. Seroprevalence of Antibodies to Severe Acute Respiratory Syndrome Coronavirus 2 Among Healthcare Workers in Kenya. Clin Infect Dis 2022; 74:288-293. [PMID: 33893491 PMCID: PMC8135298 DOI: 10.1093/cid/ciab346] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Few studies have assessed the seroprevalence of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among healthcare workers (HCWs) in Africa. We report findings from a survey among HCWs in 3 counties in Kenya. METHODS We recruited 684 HCWs from Kilifi (rural), Busia (rural), and Nairobi (urban) counties. The serosurvey was conducted between 30 July and 4 December 2020. We tested for immunoglobulin G antibodies to SARS-CoV-2 spike protein, using enzyme-linked immunosorbent assay. Assay sensitivity and specificity were 92.7 (95% CI, 87.9-96.1) and 99.0% (95% CI, 98.1-99.5), respectively. We adjusted prevalence estimates, using bayesian modeling to account for assay performance. RESULTS The crude overall seroprevalence was 19.7% (135 of 684). After adjustment for assay performance, seroprevalence was 20.8% (95% credible interval, 17.5%-24.4%). Seroprevalence varied significantly (P < .001) by site: 43.8% (95% credible interval, 35.8%-52.2%) in Nairobi, 12.6% (8.8%-17.1%) in Busia and 11.5% (7.2%-17.6%) in Kilifi. In a multivariable model controlling for age, sex, and site, professional cadre was not associated with differences in seroprevalence. CONCLUSION These initial data demonstrate a high seroprevalence of antibodies to SARS-CoV-2 among HCWs in Kenya. There was significant variation in seroprevalence by region, but not by cadre.
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Affiliation(s)
| | - Ruth Lucinde
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
| | - Henry Karanja
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Daisy Mugo
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - John Gitonga
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
| | - James Tuju
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Angela Karani
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Hosea Maroko
- KEMRI Center for Infectious and Parasitic Diseases Control Research, Alupe, Kenya
| | | | | | | | | | | | | | | | | | | | | | - David Mukabi
- Department of Health, Busia County, Busia, Kenya
| | | | | | | | - Mark Otiende
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
| | - Christian Bottomley
- Department of Infectious Diseases Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Edward Otieno
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Amek Nyaguara
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
| | - Shirine Voller
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
- Department of Infectious Diseases Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | | | | | - Rashid Aman
- Ministry of Health, Government of Kenya, Nairobi, Kenya
| | - Patrick Amoth
- Ministry of Health, Government of Kenya, Nairobi, Kenya
| | | | | | - Wangari Ng’ang’a
- Presidential Policy and Strategy Unit, The Presidency, Government of Kenya, Nairobi, Kenya
| | - Ifedayo M O Adetifa
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
- Department of Infectious Diseases Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Katherine Gallagher
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
- Department of Infectious Diseases Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Sophie Uyoga
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Edwine Barasa
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
| | - Philip Bejon
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
- Nuffield Department of Medicine, Oxford University, Oxford, United Kingdom
| | - J Anthony G Scott
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
- Department of Infectious Diseases Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - George M Warimwe
- KEMRI–Wellcome Trust Research Programme, Kilifi, Kenya
- Nuffield Department of Medicine, Oxford University, Oxford, United Kingdom
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8
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Lucinde RK, Mugo D, Bottomley C, Karani A, Gardiner E, Aziza R, Gitonga JN, Karanja H, Nyagwange J, Tuju J, Wanjiku P, Nzomo E, Kamuri E, Thuranira K, Agunda S, Nyutu G, Etyang AO, Adetifa IMO, Kagucia E, Uyoga S, Otiende M, Otieno E, Ndwiga L, Agoti CN, Aman RA, Mwangangi M, Amoth P, Kasera K, Nyaguara A, Ng’ang’a W, Ochola LB, Namdala E, Gaunya O, Okuku R, Barasa E, Bejon P, Tsofa B, Ochola-Oyier LI, Warimwe GM, Agweyu A, Scott JAG, Gallagher KE. Sero-surveillance for IgG to SARS-CoV-2 at antenatal care clinics in three Kenyan referral hospitals: Repeated cross-sectional surveys 2020-21. PLoS One 2022; 17:e0265478. [PMID: 36240176 PMCID: PMC9565697 DOI: 10.1371/journal.pone.0265478] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 09/13/2022] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION The high proportion of SARS-CoV-2 infections that have remained undetected presents a challenge to tracking the progress of the pandemic and estimating the extent of population immunity. METHODS We used residual blood samples from women attending antenatal care services at three hospitals in Kenya between August 2020 and October 2021and a validated IgG ELISA for SARS-Cov-2 spike protein and adjusted the results for assay sensitivity and specificity. We fitted a two-component mixture model as an alternative to the threshold analysis to estimate of the proportion of individuals with past SARS-CoV-2 infection. RESULTS We estimated seroprevalence in 2,981 women; 706 in Nairobi, 567 in Busia and 1,708 in Kilifi. By October 2021, 13% of participants were vaccinated (at least one dose) in Nairobi, 2% in Busia. Adjusted seroprevalence rose in all sites; from 50% (95%CI 42-58) in August 2020, to 85% (95%CI 78-92) in October 2021 in Nairobi; from 31% (95%CI 25-37) in May 2021 to 71% (95%CI 64-77) in October 2021 in Busia; and from 1% (95% CI 0-3) in September 2020 to 63% (95% CI 56-69) in October 2021 in Kilifi. Mixture modelling, suggests adjusted cross-sectional prevalence estimates are underestimates; seroprevalence in October 2021 could be 74% in Busia and 72% in Kilifi. CONCLUSIONS There has been substantial, unobserved transmission of SARS-CoV-2 in Nairobi, Busia and Kilifi Counties. Due to the length of time since the beginning of the pandemic, repeated cross-sectional surveys are now difficult to interpret without the use of models to account for antibody waning.
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Affiliation(s)
- Ruth K. Lucinde
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- * E-mail:
| | - Daisy Mugo
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Christian Bottomley
- Department of Infectious Diseases Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Angela Karani
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Rabia Aziza
- School of Life Sciences and the Zeeman Institute for Systems Biology & Infectious Disease Epidemiology Research (SBIDER), University of Warwick, Coventry, United Kingdom
| | | | - Henry Karanja
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - James Tuju
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Edward Nzomo
- Kilifi County Hospital, Ministry of Health, Government of Kenya, Nairobi, Kenya
| | - Evans Kamuri
- Kenyatta National Hospital, Ministry of Health, Government of Kenya, Nairobi, Kenya
| | - Kaugiria Thuranira
- Kenyatta National Hospital, Ministry of Health, Government of Kenya, Nairobi, Kenya
| | - Sarah Agunda
- Kenyatta National Hospital, Ministry of Health, Government of Kenya, Nairobi, Kenya
| | - Gideon Nyutu
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Ifedayo M. O. Adetifa
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Department of Infectious Diseases Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Sophie Uyoga
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Mark Otiende
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Edward Otieno
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | | | | | | | - Patrick Amoth
- Ministry of Health, Government of Kenya, Nairobi, Kenya
| | | | - Amek Nyaguara
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Wangari Ng’ang’a
- Presidential Policy and Strategy Unit, The Presidency, Government of Kenya, Nairobi, Kenya
| | | | | | - Oscar Gaunya
- Busia Country Teaching & Referral Hospital, Busia, Kenya
| | - Rosemary Okuku
- Busia Country Teaching & Referral Hospital, Busia, Kenya
| | - Edwine Barasa
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Nuffield Department of Medicine, Oxford University, Oxford, United Kingdom
| | - Philip Bejon
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Nuffield Department of Medicine, Oxford University, Oxford, United Kingdom
| | | | | | - George M. Warimwe
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Nuffield Department of Medicine, Oxford University, Oxford, United Kingdom
| | | | - J. Anthony G. Scott
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Department of Infectious Diseases Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
- Nuffield Department of Medicine, Oxford University, Oxford, United Kingdom
| | - Katherine E. Gallagher
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Department of Infectious Diseases Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
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9
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Bottomley C, Otiende M, Uyoga S, Gallagher K, Kagucia EW, Etyang AO, Mugo D, Gitonga J, Karanja H, Nyagwange J, Adetifa IMO, Agweyu A, Nokes DJ, Warimwe GM, Scott JAG. Quantifying previous SARS-CoV-2 infection through mixture modelling of antibody levels. Nat Commun 2021; 12:6196. [PMID: 34702829 PMCID: PMC8548402 DOI: 10.1038/s41467-021-26452-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 09/17/2021] [Indexed: 11/09/2022] Open
Abstract
As countries decide on vaccination strategies and how to ease movement restrictions, estimating the proportion of the population previously infected with SARS-CoV-2 is important for predicting the future burden of COVID-19. This proportion is usually estimated from serosurvey data in two steps: first the proportion above a threshold antibody level is calculated, then the crude estimate is adjusted using external estimates of sensitivity and specificity. A drawback of this approach is that the PCR-confirmed cases used to estimate the sensitivity of the threshold may not be representative of cases in the wider population-e.g., they may be more recently infected and more severely symptomatic. Mixture modelling offers an alternative approach that does not require external data from PCR-confirmed cases. Here we illustrate the bias in the standard threshold-based approach by comparing both approaches using data from several Kenyan serosurveys. We show that the mixture model analysis produces estimates of previous infection that are often substantially higher than the standard threshold analysis.
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Affiliation(s)
- C Bottomley
- International Statistics and Epidemiology Group, London School of Hygiene & Tropical Medicine, London, UK.
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK.
| | - M Otiende
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - S Uyoga
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - K Gallagher
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - E W Kagucia
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - A O Etyang
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - D Mugo
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - J Gitonga
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - H Karanja
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - J Nyagwange
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - I M O Adetifa
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - A Agweyu
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Nuffield Department of Medicine, Oxford University, Oxford, UK
| | - D J Nokes
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- School of Life Sciences, University of Warwick, Coventry, UK
| | - G M Warimwe
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Nuffield Department of Medicine, Oxford University, Oxford, UK
| | - J A G Scott
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Nuffield Department of Medicine, Oxford University, Oxford, UK
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10
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Kagucia EW, Gitonga JN, Kalu C, Ochomo E, Ochieng B, Kuya N, Karani A, Nyagwange J, Karia B, Mugo D, Karanja HK, Tuju J, Mutiso A, Maroko H, Okubi L, Maitha E, Ajuck H, Mukabi D, Moracha W, Bulimu D, Andanje N, Aman R, Mwangangi M, Amoth P, Kasera K, Ng'ang'a W, Nyaguara A, Voller S, Otiende M, Bottomley C, Agoti CN, Ochola-Oyier LI, Adetifa IMO, Etyang AO, Gallagher KE, Uyoga S, Barasa E, Bejon P, Tsofa B, Agweyu A, Warimwe GM, Scott JAG. Anti-Severe Acute Respiratory Syndrome Coronavirus 2 Immunoglobulin G Antibody Seroprevalence Among Truck Drivers and Assistants in Kenya. Open Forum Infect Dis 2021; 8:ofab314. [PMID: 34660838 PMCID: PMC8519263 DOI: 10.1093/ofid/ofab314] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 06/09/2021] [Indexed: 11/14/2022] Open
Abstract
In October 2020, anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin G seroprevalence among truck drivers and their assistants (TDA) in Kenya was 42.3%, higher than among healthcare workers and blood donors. Truck drivers and their assistants transport essential supplies during the coronavirus disease 2019 pandemic, placing them at increased risk of being infected and of transmitting SARS-CoV-2 over a wide geographical area.
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Affiliation(s)
| | | | | | - Eric Ochomo
- KEMRI Centre for Global Health Research (CGHR), Kisumu, Kenya
| | - Benard Ochieng
- KEMRI Centre for Global Health Research (CGHR), Kisumu, Kenya
| | - Nickline Kuya
- KEMRI Centre for Global Health Research (CGHR), Kisumu, Kenya
| | - Angela Karani
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | | | - Daisy Mugo
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - James Tuju
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Agnes Mutiso
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Hosea Maroko
- KEMRI Centre for Infectious and Parasitic Diseases Control Research, Busia, Kenya
| | - Lucy Okubi
- KEMRI Centre for Infectious and Parasitic Diseases Control Research, Busia, Kenya
| | | | | | | | | | | | | | - Rashid Aman
- Ministry of Health, Government of Kenya, Nairobi, Kenya
| | | | - Patrick Amoth
- Ministry of Health, Government of Kenya, Nairobi, Kenya
| | | | - Wangari Ng'ang'a
- Presidential Policy and Strategy Unit, The Presidency, Government of Kenya, Nairobi, Kenya
| | - Amek Nyaguara
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Shirine Voller
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya.,Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Mark Otiende
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Christian Bottomley
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | | | - Ifedayo M O Adetifa
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya.,Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | - Katherine E Gallagher
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya.,Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Sophie Uyoga
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Edwine Barasa
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Philip Bejon
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya.,Nuffield Department of Medicine, Oxford University, Oxford, United Kingdom
| | | | | | - George M Warimwe
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya.,Nuffield Department of Medicine, Oxford University, Oxford, United Kingdom
| | - J Anthony G Scott
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya.,Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom.,Nuffield Department of Medicine, Oxford University, Oxford, United Kingdom
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11
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Muriuki JM, Mentzer AJ, Mitchell R, Webb EL, Etyang AO, Kyobutungi C, Morovat A, Kimita W, Ndungu FM, Macharia AW, Ngetsa CJ, Makale J, Lule SA, Musani SK, Raffield LM, Cutland CL, Sirima SB, Diarra A, Tiono AB, Fried M, Gwamaka M, Adu-Afarwuah S, Wirth JP, Wegmüller R, Madhi SA, Snow RW, Hill AVS, Rockett KA, Sandhu MS, Kwiatkowski DP, Prentice AM, Byrd KA, Ndjebayi A, Stewart CP, Engle-Stone R, Green TJ, Karakochuk CD, Suchdev PS, Bejon P, Duffy PE, Davey Smith G, Elliott AM, Williams TN, Atkinson SH. Malaria is a cause of iron deficiency in African children. Nat Med 2021; 27:653-658. [PMID: 33619371 PMCID: PMC7610676 DOI: 10.1038/s41591-021-01238-4] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 01/12/2021] [Indexed: 12/12/2022]
Abstract
Malaria and iron deficiency (ID) are common and interrelated public health problems in African children. Observational data suggest that interrupting malaria transmission reduces the prevalence of ID1. To test the hypothesis that malaria might cause ID, we used sickle cell trait (HbAS, rs334 ), a genetic variant that confers specific protection against malaria2, as an instrumental variable in Mendelian randomization analyses. HbAS was associated with a 30% reduction in ID among children living in malaria-endemic countries in Africa (n = 7,453), but not among individuals living in malaria-free areas (n = 3,818). Genetically predicted malaria risk was associated with an odds ratio of 2.65 for ID per unit increase in the log incidence rate of malaria. This suggests that an intervention that halves the risk of malaria episodes would reduce the prevalence of ID in African children by 49%.
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Affiliation(s)
- John Muthii Muriuki
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya.
- Open University, KEMRI-Wellcome Trust Research Programme, Accredited Research Centre, Kilifi, Kenya.
| | - Alexander J Mentzer
- Wellcome Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, UK
| | - Ruth Mitchell
- Medical Research Council (MRC) Integrative Epidemiology Unit, Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Emily L Webb
- MRC Tropical Epidemiology Group, Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
| | - Anthony O Etyang
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Alireza Morovat
- Department of Clinical Biochemistry, Oxford University Hospitals, Oxford, UK
| | - Wandia Kimita
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Francis M Ndungu
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Alex W Macharia
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Caroline J Ngetsa
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Johnstone Makale
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Swaib A Lule
- MRC/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda
| | - Solomon K Musani
- Department of Medicine, University of Mississippi Medical Center, Jackson, MS, USA
| | - Laura M Raffield
- Department of Genetics, University of North Carolina, Chapel Hill, NC, USA
| | - Clare L Cutland
- South African Medical Research Council: Vaccines and Infectious Diseases Analytical Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Sodiomon B Sirima
- Groupe de Recherche Action en Sante (GRAS), 06 BP 10248, Ouagadougou, Burkina Faso
| | - Amidou Diarra
- Groupe de Recherche Action en Sante (GRAS), 06 BP 10248, Ouagadougou, Burkina Faso
| | - Alfred B Tiono
- Groupe de Recherche Action en Sante (GRAS), 06 BP 10248, Ouagadougou, Burkina Faso
| | - Michal Fried
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Moses Gwamaka
- Mother Offspring Malaria Studies (MOMS) Project, Seattle Biomedical Research Institute, Seattle, WA, USA
- Muheza Designated District Hospital, Muheza, Tanzania
- University of Dar es Salaam, Mbeya College of Health and Allied Sciences, Mbeya, Tanzania
| | - Seth Adu-Afarwuah
- Department of Nutrition and Food Science, University of Ghana, Legon, Ghana
| | | | | | - Shabir A Madhi
- South African Medical Research Council: Vaccines and Infectious Diseases Analytical Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Robert W Snow
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Adrian V S Hill
- Wellcome Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Centre for Clinical Vaccinology and Tropical Medicine and the Jenner Institute Laboratories, University of Oxford, Oxford, UK
| | - Kirk A Rockett
- Wellcome Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Wellcome Sanger Institute, Hinxton, UK
| | | | - Dominic P Kwiatkowski
- Wellcome Centre for Human Genetics, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Big Data Institute, Li Ka Shing Centre for Health Information and Discovery, University of Oxford, Oxford, UK
- Wellcome Sanger Institute, Hinxton, UK
| | - Andrew M Prentice
- MRC Unit The Gambia at London School of Hygiene and Tropical Medicine, Banjul, The Gambia
| | | | | | | | - Reina Engle-Stone
- Department of Nutrition, University of California, Davis, Davis, CA, USA
| | - Tim J Green
- SAHMRi Women and Kids, South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
- School of Medicine, The University of Adelaide, Adelaide, South Australia, Australia
| | - Crystal D Karakochuk
- Food, Nutrition, and Health, University of British Columbia, Vancouver, British Columbia, Canada
| | - Parminder S Suchdev
- Department of Pediatrics, Emory University and Emory Global Health Institute, Atlanta, GA, USA
| | - Philip Bejon
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Patrick E Duffy
- Laboratory of Malaria Immunology and Vaccinology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - George Davey Smith
- Medical Research Council (MRC) Integrative Epidemiology Unit, Population Health Sciences, Bristol Medical School, University of Bristol, Bristol, UK
| | - Alison M Elliott
- MRC/Uganda Virus Research Institute and London School of Hygiene and Tropical Medicine Uganda Research Unit, Entebbe, Uganda
- Department of Clinical Research, London School of Hygiene and Tropical Medicine, London, UK
| | - Thomas N Williams
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Department of Infectious Diseases and Institute of Global Health Innovation, Imperial College, London, UK
| | - Sarah H Atkinson
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine Research, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya.
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
- Department of Paediatrics, University of Oxford, Oxford, UK.
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12
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Seeley A, Prynn J, Perera R, Street R, Davis D, Etyang AO. Pharmacotherapy for hypertension in Sub-Saharan Africa: a systematic review and network meta-analysis. BMC Med 2020; 18:75. [PMID: 32216794 PMCID: PMC7099775 DOI: 10.1186/s12916-020-01530-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Accepted: 02/13/2020] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND The highest burden of hypertension is found in Sub-Saharan Africa (SSA) with a threefold greater mortality from stroke and other associated diseases. Ethnicity is known to influence the response to antihypertensives, especially in black populations living in North America and Europe. We sought to outline the impact of all commonly used pharmacological agents on both blood pressure reduction and cardiovascular morbidity and mortality in SSA. METHODS We used similar criteria to previous large meta-analyses of blood pressure agents but restricted results to populations in SSA. Quality of evidence was assessed using a risk of bias tool. Network meta-analysis with random effects was used to compare the effects across interventions and meta-regression to explore participant heterogeneity. RESULTS Thirty-two studies of 2860 participants were identified. Most were small studies from single, urban centres. Compared with placebo, any pharmacotherapy lowered SBP/DBP by 8.51/8.04 mmHg, and calcium channel blockers (CCBs) were the most efficacious first-line agent with 18.46/11.6 mmHg reduction. Fewer studies assessing combination therapy were available, but there was a trend towards superiority for CCBs plus ACE inhibitors or diuretics compared to other combinations. No studies examined the effect of antihypertensive therapy on morbidity or mortality outcomes. CONCLUSION Evidence broadly supports current guidelines and provides a clear rationale for promoting CCBs as first-line agents and early initiation of combination therapy. However, there is a clear requirement for more evidence to provide a nuanced understanding of stroke and other cardiovascular disease prevention amongst diverse populations on the continent. TRIAL REGISTRATION PROSPERO, CRD42019122490. This review was registered in January 2019.
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Affiliation(s)
- Anna Seeley
- Medical Research Council Unit Lifelong Health and Ageing at UCL, Department of Population Science and Experimental Medicine, University College London, London, UK.
- Nuffiend Department of Primary Health Care Sciences, Woodstock Road, Oxford, OX2 6GG, UK.
| | | | - Rachel Perera
- Medical Research Council Unit Lifelong Health and Ageing at UCL, Department of Population Science and Experimental Medicine, University College London, London, UK
| | - Rebecca Street
- Medical Research Council Unit Lifelong Health and Ageing at UCL, Department of Population Science and Experimental Medicine, University College London, London, UK
| | - Daniel Davis
- Medical Research Council Unit Lifelong Health and Ageing at UCL, Department of Population Science and Experimental Medicine, University College London, London, UK
| | - Anthony O Etyang
- Department of Epidemiology and Demography, KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
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13
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Muthumbi EM, Gordon NC, Mochamah G, Nyongesa S, Odipo E, Mwarumba S, Mturi N, Etyang AO, Dance DAB, Scott JAG, Morpeth SC. Population-Based Estimate of Melioidosis, Kenya. Emerg Infect Dis 2019; 25:984-987. [PMID: 31002067 PMCID: PMC6478202 DOI: 10.3201/eid2505.180545] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Melioidosis is thought to be endemic, although underdiagnosed, in Africa. We identified 5 autochthonous cases of Burkholderia pseudomallei infection in a case series in Kenya. Incidence of B. pseudomallei bacteremia in Kenya’s Kilifi County is low, at 1.5 cases per million person-years, but this result might be an underestimate.
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14
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Etyang AO, Sigilai A, Odipo E, Oyando R, Ong'ayo G, Muthami L, Munge K, Kirui F, Mbui J, Bukania Z, Mwai J, Obala A, Barasa E. Diagnostic Accuracy of Unattended Automated Office Blood Pressure Measurement in Screening for Hypertension in Kenya. Hypertension 2019; 74:1490-1498. [PMID: 31587589 PMCID: PMC7069390 DOI: 10.1161/hypertensionaha.119.13574] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Supplemental Digital Content is available in the text. Despite increasing adoption of unattended automated office blood pressure (uAOBP) measurement for determining clinic blood pressure (BP), its diagnostic performance in screening for hypertension in low-income settings has not been determined. We determined the validity of uAOBP in screening for hypertension, using 24-hour ambulatory BP monitoring as the reference standard. We studied a random population sample of 982 Kenyan adults; mean age, 42 years; 60% women; 2% with diabetes mellitus; none taking antihypertensive medications. We calculated sensitivity using 3 different screen positivity cutoffs (≥130/80, ≥135/85, and ≥140/90 mm Hg) and other measures of validity/agreement. Mean 24-hour ambulatory BP monitoring systolic BP was similar to mean uAOBP systolic BP (mean difference, 0.6 mm Hg; 95% CI, −0.6 to 1.9), but the 95% limits of agreement were wide (−39 to 40 mm Hg). Overall discriminatory accuracy of uAOBP was the same (area under receiver operating characteristic curves, 0.66–0.68; 95% CI range, 0.64–0.71) irrespective of uAOBP cutoffs used. Sensitivity of uAOBP displayed an inverse association (P<0.001) with the cutoff selected, progressively decreasing from 67% (95% CI, 62–72) when using a cutoff of ≥130/80 mm Hg to 55% (95% CI, 49–60) at ≥135/85 mm Hg to 44% (95% CI, 39–49) at ≥140/90 mm Hg. Diagnostic performance was significantly better (P<0.001) in overweight and obese individuals (body mass index, >25 kg/m2). No differences in results were present in other subanalyses. uAOBP misclassifies significant proportions of individuals undergoing screening for hypertension in Kenya. Additional studies on how to improve screening strategies in this setting are needed.
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Affiliation(s)
- Anthony O Etyang
- From the Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme (A.O.E., A.S., E.O., G.O.)
| | - Antipa Sigilai
- From the Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme (A.O.E., A.S., E.O., G.O.)
| | - Emily Odipo
- From the Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme (A.O.E., A.S., E.O., G.O.)
| | - Robinson Oyando
- Health Economics Research Unit, KEMRI Wellcome Trust Research Programme, Nairobi, Kenya (R.O., K.M., E.B.)
| | - Gerald Ong'ayo
- From the Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme (A.O.E., A.S., E.O., G.O.)
| | - Lawrence Muthami
- Centre for Public Health Research (L.M., Z.B., J.M.), Kenya Medical Research Institute, Nairobi
| | - Kenneth Munge
- Health Economics Research Unit, KEMRI Wellcome Trust Research Programme, Nairobi, Kenya (R.O., K.M., E.B.)
| | - Fredrick Kirui
- Centre for Clinical Research (F.K., J.M.), Kenya Medical Research Institute, Nairobi
| | - Jane Mbui
- Centre for Clinical Research (F.K., J.M.), Kenya Medical Research Institute, Nairobi
| | - Zipporah Bukania
- Centre for Public Health Research (L.M., Z.B., J.M.), Kenya Medical Research Institute, Nairobi
| | - Judy Mwai
- Centre for Public Health Research (L.M., Z.B., J.M.), Kenya Medical Research Institute, Nairobi
| | | | - Edwine Barasa
- Health Economics Research Unit, KEMRI Wellcome Trust Research Programme, Nairobi, Kenya (R.O., K.M., E.B.)
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Ong'ayo G, Ooko M, Wang'ondu R, Bottomley C, Nyaguara A, Tsofa BK, Williams TN, Bejon P, Scott JAG, Etyang AO. Effect of strikes by health workers on mortality between 2010 and 2016 in Kilifi, Kenya: a population-based cohort analysis. Lancet Glob Health 2019; 7:e961-e967. [PMID: 31129126 PMCID: PMC6560003 DOI: 10.1016/s2214-109x(19)30188-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 03/15/2019] [Accepted: 03/29/2019] [Indexed: 12/30/2022]
Abstract
BACKGROUND Health workers' strikes are a global occurrence. Kenya has had several strikes by health workers in recent years but their effect on mortality is unknown. We assessed the effect on mortality of six strikes by health workers that occurred from 2010 to 2016 in Kilifi, Kenya. METHODS Using daily mortality data obtained from the Kilifi Health and Demographic Surveillance System, we fitted a negative binomial regression model to estimate the change in mortality during strike periods and in the 2 weeks immediately after strikes. We did subgroup analyses by age, cause of death, and strike week. FINDINGS Between Jan 1, 2010, and Nov 30, 2016, we recorded 1 829 929 person-years of observation, 6396 deaths, and 128 strike days (median duration of strikes, 18·5 days [range 9-42]). In the primary analysis, no change in all-cause mortality was noted during strike periods (adjusted rate ratio [RR] 0·93, 95% CI 0·81-1·08; p=0·34). Weak evidence was recorded of variation in mortality rates by age group, with an apparent decrease among infants aged 1-11 months (adjusted RR 0·58, 95% CI 0·33-1·03; p=0·064) and an increase among children aged 12-59 months (1·75, 1·11-2·76; p=0·016). No change was noted in mortality rates in post-strike periods and for any category of cause of death. INTERPRETATION The brief strikes by health workers during the period 2010-16 were not associated with obvious changes in overall mortality in Kilifi. The combined effects of private (and some public) health care during strike periods, a high proportion of out-of-hospital deaths, and a low number of events might have led us to underestimate the effect. FUNDING Wellcome Trust and MRC Tropical Epidemiology Group.
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Affiliation(s)
- Gerald Ong'ayo
- Department of Epidemiology and Demography, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya. GOng'
| | - Michael Ooko
- Department of Epidemiology and Demography, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Christian Bottomley
- Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Amek Nyaguara
- Department of Epidemiology and Demography, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Benjamin K Tsofa
- Department of Epidemiology and Demography, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Thomas N Williams
- Department of Epidemiology and Demography, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya; Imperial College, London, UK
| | - Philip Bejon
- Department of Epidemiology and Demography, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya; Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - J Anthony G Scott
- Department of Epidemiology and Demography, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya; Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Anthony O Etyang
- Department of Epidemiology and Demography, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
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16
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Affiliation(s)
- Anthony O Etyang
- Department of Epidemiology and Demography, KEMRI Wellcome Trust Research Programme, Kilifi, Kenya.,Kilifi County Hospital, Kilifi, Kenya
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17
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Hammitt LL, Etyang AO, Morpeth SC, Ojal J, Mutuku A, Mturi N, Moisi JC, Adetifa IM, Karani A, Akech DO, Otiende M, Bwanaali T, Wafula J, Mataza C, Mumbo E, Tabu C, Knoll MD, Bauni E, Marsh K, Williams TN, Kamau T, Sharif SK, Levine OS, Scott JAG. Effect of ten-valent pneumococcal conjugate vaccine on invasive pneumococcal disease and nasopharyngeal carriage in Kenya: a longitudinal surveillance study. Lancet 2019; 393:2146-2154. [PMID: 31000194 PMCID: PMC6548991 DOI: 10.1016/s0140-6736(18)33005-8] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Revised: 10/19/2018] [Accepted: 11/15/2018] [Indexed: 01/20/2023]
Abstract
BACKGROUND Ten-valent pneumococcal conjugate vaccine (PCV10), delivered at 6, 10, and 14 weeks of age was introduced in Kenya in January, 2011, accompanied by a catch-up campaign in Kilifi County for children aged younger than 5 years. Coverage with at least two PCV10 doses in children aged 2-11 months was 80% in 2011 and 84% in 2016; coverage with at least one dose in children aged 12-59 months was 66% in 2011 and 87% in 2016. We aimed to assess PCV10 effect against nasopharyngeal carriage and invasive pneumococcal disease (IPD) in children and adults in Kilifi County. METHODS This study was done at the KEMRI-Wellcome Trust Research Programme among residents of the Kilifi Health and Demographic Surveillance System, a rural community on the Kenyan coast covering an area of 891 km2. We linked clinical and microbiological surveillance for IPD among admissions of all ages at Kilifi County Hospital, Kenya, which serves the community, to the Kilifi Health and Demographic Surveillance System from 1999 to 2016. We calculated the incidence rate ratio (IRR) comparing the prevaccine (Jan 1, 1999-Dec 31, 2010) and postvaccine (Jan 1, 2012-Dec 31, 2016) eras, adjusted for confounding, and reported percentage reduction in IPD as 1 minus IRR. Annual cross-sectional surveys of nasopharyngeal carriage were done from 2009 to 2016. FINDINGS Surveillance identified 667 cases of IPD in 3 211 403 person-years of observation. Yearly IPD incidence in children younger than 5 years reduced sharply in 2011 following vaccine introduction and remained low (PCV10-type IPD: 60·8 cases per 100 000 in the prevaccine era vs 3·2 per 100 000 in the postvaccine era [adjusted IRR 0·08, 95% CI 0·03-0·22]; IPD caused by any serotype: 81·6 per 100 000 vs 15·3 per 100 000 [0·32, 0·17-0·60]). PCV10-type IPD also declined in the post-vaccination era in unvaccinated age groups (<2 months [no cases in the postvaccine era], 5-14 years [adjusted IRR 0·26, 95% CI 0·11-0·59], and ≥15 years [0·19, 0·07-0·51]). Incidence of non-PCV10-type IPD did not differ between eras. In children younger than 5 years, PCV10-type carriage declined between eras (age-standardised adjusted prevalence ratio 0·26, 95% CI 0·19-0·35) and non-PCV10-type carriage increased (1·71, 1·47-1·99). INTERPRETATION Introduction of PCV10 in Kenya, accompanied by a catch-up campaign, resulted in a substantial reduction in PCV10-type IPD in children and adults without significant replacement disease. Although the catch-up campaign is likely to have brought forward the benefits by several years, the study suggests that routine infant PCV10 immunisation programmes will provide substantial direct and indirect protection in low-income settings in tropical Africa. FUNDING Gavi, The Vaccine Alliance and The Wellcome Trust of Great Britain.
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Affiliation(s)
- Laura L Hammitt
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya; Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK; Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
| | - Anthony O Etyang
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya; Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Susan C Morpeth
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya; Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK; Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - John Ojal
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya; Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Alex Mutuku
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya
| | - Neema Mturi
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya
| | - Jennifer C Moisi
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya; Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK; Pfizer Vaccines, Paris, France
| | - Ifedayo M Adetifa
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya; Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK
| | - Angela Karani
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya
| | - Donald O Akech
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya
| | - Mark Otiende
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya
| | - Tahreni Bwanaali
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya; Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Jackline Wafula
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya
| | | | | | - Collins Tabu
- National Vaccines and Immunization Programme, Ministry of Health, Kenya
| | - Maria Deloria Knoll
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Evasius Bauni
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya
| | - Kevin Marsh
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya; Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Thomas N Williams
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya; Imperial College, London, UK; INDEPTH Network, Accra, Ghana
| | - Tatu Kamau
- National Vaccines and Immunization Programme, Ministry of Health, Kenya
| | - Shahnaaz K Sharif
- National Vaccines and Immunization Programme, Ministry of Health, Kenya
| | - Orin S Levine
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA; Bill & Melinda Gates Foundation, Seattle, WA, USA
| | - J Anthony G Scott
- Epidemiology and Demography Department, KEMRI-Wellcome Trust Research Programme, Centre for Geographic Medicine-Coast, Kilifi, Kenya; Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK; Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, UK; INDEPTH Network, Accra, Ghana
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Etyang AO, Kapesa S, Odipo E, Bauni E, Kyobutungi C, Abdalla M, Muntner P, Musani SK, Macharia A, Williams TN, Cruickshank JK, Smeeth L, Scott JAG. Effect of Previous Exposure to Malaria on Blood Pressure in Kilifi, Kenya: A Mendelian Randomization Study. J Am Heart Assoc 2019; 8:e011771. [PMID: 30879408 PMCID: PMC6475058 DOI: 10.1161/jaha.118.011771] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 02/05/2019] [Indexed: 12/31/2022]
Abstract
Background Malaria exposure in childhood may contribute to high blood pressure ( BP ) in adults. We used sickle cell trait ( SCT ) and α+thalassemia, genetic variants conferring partial protection against malaria, as tools to test this hypothesis. Methods and Results Study sites were Kilifi, Kenya, which has malaria transmission, and Nairobi, Kenya, and Jackson, Mississippi, where there is no malaria transmission. The primary outcome was 24-hour systolic BP. Prevalent hypertension, diagnosed using European Society of Hypertension thresholds was a secondary outcome. We performed regression analyses adjusting for age, sex, and estimated glomerular filtration rate. We studied 1127 participants in Kilifi, 516 in Nairobi, and 651 in Jackson. SCT frequency was 21% in Kilifi, 16% in Nairobi, and 9% in Jackson. SCT was associated with -2.4 (95% CI , -4.7 to -0.2) mm Hg lower 24-hour systolic BP in Kilifi but had no effect in Nairobi/Jackson. The effect of SCT in Kilifi was limited to 30- to 59-year-old participants, among whom it was associated with -6.1 mm Hg ( CI , -10.5 to -1.8) lower 24-hour systolic BP. In pooled analysis allowing interaction by site, the effect of SCT on 24-hour systolic BP in Kilifi was -3.5 mm Hg ( CI , -6.9 to -0.1), increasing to -5.2 mm Hg ( CI , -9.5 to -0.9) when replacing estimated glomerular filtration rate with urine albumin to creatinine ratio as a covariate. In Kilifi, the prevalence ratio for hypertension was 0.86 ( CI , 0.76-0.98) for SCT and 0.89 ( CI , 0.80-0.99) for α+thalassemia. Conclusions Lifelong malaria protection is associated with lower BP in Kilifi. Confirmation of this finding at other sites and elucidating the mechanisms involved may yield new preventive and therapeutic targets.
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Affiliation(s)
- Anthony O. Etyang
- KEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
- London School of Hygiene and Tropical MedicineLondonUnited Kingdom
| | | | - Emily Odipo
- KEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
| | | | | | | | | | | | | | - Thomas N. Williams
- KEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
- Imperial CollegeLondonUnited Kingdom
| | | | - Liam Smeeth
- London School of Hygiene and Tropical MedicineLondonUnited Kingdom
| | - J. Anthony G. Scott
- KEMRI‐Wellcome Trust Research ProgrammeKilifiKenya
- London School of Hygiene and Tropical MedicineLondonUnited Kingdom
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Etyang AO, Wandabwa CK, Kapesa S, Muthumbi E, Odipo E, Wamukoya M, Ngomi N, Haregu T, Kyobutungi C, Williams TN, Makale J, Macharia A, Cruickshank JK, Smeeth L, Scott JAG. Blood Pressure and Arterial Stiffness in Kenyan Adolescents With the Sickle Cell Trait. Am J Epidemiol 2018; 187:199-205. [PMID: 28992220 PMCID: PMC5860135 DOI: 10.1093/aje/kwx232] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Accepted: 05/22/2017] [Indexed: 01/28/2023] Open
Abstract
The potential association between sickle cell trait (SCT) and increased arterial stiffness/blood pressure (BP) has not been evaluated in detail despite its association with stroke, sudden death, and renal disease. We performed 24-hour ambulatory BP monitoring and arterial stiffness measurements in adolescents raised in a malaria-free environment in Kenya. Between December 2015 and June 2016, 938 randomly selected adolescents (ages 11–17 years) who had been continuous residents of Nairobi from birth were invited to participate in the study. Standard clinic BP measurement was performed, followed by 24-hour ambulatory BP monitoring and arterial stiffness measurement using an Arteriograph24 (TensioMed Ltd., Budapest, Hungary) device. SCT status was determined using DNA genotyping in contemporaneously collected blood samples. Of the 938 adolescents invited to participate, 609 (65%) provided complete data for analysis. SCT was present in 103 (15%). Mean 24-hour systolic and diastolic BPs were 116 (standard deviation (SD), 11.5) mm Hg and 64 (SD, 7) mm Hg, respectively, in children with SCT and 117 (SD, 11.4) mm Hg and 64 (SD, 6.8) mm Hg, respectively, in non-SCT children. Mean pulse wave velocity (PWV) was 7.1 (SD, 0.8) m/second and 7.0 (SD, 0.8) m/second in SCT and non-SCT children, respectively. We observed no differences in PWV or in any clinic or ambulatory BP-derived measures between adolescents with and without SCT. These data suggest that SCT does not independently influence BP or PWV.
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Affiliation(s)
- Anthony O Etyang
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | | | | | - Emily Odipo
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Nicholas Ngomi
- African Population and Health Research Center, Nairobi, Kenya
| | - Tilahun Haregu
- African Population and Health Research Center, Nairobi, Kenya
| | | | - Thomas N Williams
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
- Imperial College London, London, United Kingdom
| | | | - Alex Macharia
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Liam Smeeth
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - J Anthony G Scott
- KEMRI Wellcome Trust Research Programme, Kilifi, Kenya
- London School of Hygiene and Tropical Medicine, London, United Kingdom
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20
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Etyang AO, Khayeka-Wandabwa C, Kapesa S, Muthumbi E, Odipo E, Wamukoya M, Ngomi N, Haregu T, Kyobutungi C, Tendwa M, Makale J, Macharia A, Cruickshank JK, Smeeth L, Scott JAG, Williams TN. Blood Pressure and Arterial Stiffness in Kenyan Adolescents With α +Thalassemia. J Am Heart Assoc 2017; 6:JAHA.117.005613. [PMID: 28381468 PMCID: PMC5533038 DOI: 10.1161/jaha.117.005613] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Background Recent studies have discovered that α‐globin is expressed in blood vessel walls where it plays a role in regulating vascular tone. We tested the hypothesis that blood pressure (BP) might differ between normal individuals and those with α+thalassemia, in whom the production of α‐globin is reduced. Methods and Results The study was conducted in Nairobi, Kenya, among 938 adolescents aged 11 to 17 years. Twenty‐four‐hour ambulatory BP monitoring and arterial stiffness measurements were performed using an arteriograph device. We genotyped for α+thalassemia by polymerase chain reaction. Complete data for analysis were available for 623 subjects; 223 (36%) were heterozygous (−α/αα) and 47 (8%) were homozygous (−α/−α) for α+thalassemia whereas the remaining 353 (55%) were normal (αα/αα). Mean 24‐hour systolic BP ±SD was 118±12 mm Hg in αα/αα, 117±11 mm Hg in −α/αα, and 118±11 mm Hg in −α/−α subjects, respectively. Mean 24‐hour diastolic BP ±SD in these groups was 64±8, 63±7, and 65±8 mm Hg, respectively. Mean pulse wave velocity (PWV)±SD was 7±0.8, 7±0.8, and 7±0.7 ms−1, respectively. No differences were observed in PWV and any of the 24‐hour ambulatory BP monitoring‐derived measures between those with and without α+thalassemia. Conclusions These data suggest that the presence of α+thalassemia does not affect BP and/or arterial stiffness in Kenyan adolescents.
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Affiliation(s)
- Anthony O Etyang
- KEMRI-Wellcome Trust Research Program, Kilifi, Kenya .,London School of Hygiene and Tropical Medicine, London, United Kingdom
| | | | | | | | - Emily Odipo
- KEMRI-Wellcome Trust Research Program, Kilifi, Kenya
| | | | - Nicholas Ngomi
- African Population and Health Research Centre, Nairobi, Kenya
| | - Tilahun Haregu
- African Population and Health Research Centre, Nairobi, Kenya
| | | | | | | | - Alex Macharia
- KEMRI-Wellcome Trust Research Program, Kilifi, Kenya
| | | | - Liam Smeeth
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - J Anthony G Scott
- KEMRI-Wellcome Trust Research Program, Kilifi, Kenya.,London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Thomas N Williams
- KEMRI-Wellcome Trust Research Program, Kilifi, Kenya.,Imperial College, London, United Kingdom
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Etyang AO, Warne B, Kapesa S, Munge K, Bauni E, Cruickshank JK, Smeeth L, Scott JAG. Clinical and Epidemiological Implications of 24-Hour Ambulatory Blood Pressure Monitoring for the Diagnosis of Hypertension in Kenyan Adults: A Population-Based Study. J Am Heart Assoc 2016; 5:e004797. [PMID: 27979807 PMCID: PMC5210452 DOI: 10.1161/jaha.116.004797] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2016] [Accepted: 11/22/2016] [Indexed: 01/22/2023]
Abstract
BACKGROUND The clinical and epidemiological implications of using ambulatory blood pressure monitoring (ABPM) for the diagnosis of hypertension have not been studied at a population level in sub-Saharan Africa. We examined the impact of ABPM use among Kenyan adults. METHODS AND RESULTS We performed a nested case-control study of diagnostic accuracy. We selected an age-stratified random sample of 1248 adults from the list of residents of the Kilifi Health and Demographic Surveillance System in Kenya. All participants underwent a screening blood pressure (BP) measurement. All those with screening BP ≥140/90 mm Hg and a random subset of those with screening BP <140/90 mm Hg were invited to undergo ABPM. Based on the 2 tests, participants were categorized as sustained hypertensive, masked hypertensive, "white coat" hypertensive, or normotensive. Analyses were weighted by the probability of undergoing ABPM. Screening BP ≥140/90 mm Hg was present in 359 of 986 participants, translating to a crude population prevalence of 23.1% (95% CI 16.5-31.5%). Age standardized prevalence of screening BP ≥140/90 mm Hg was 26.5% (95% CI 19.3-35.6%). On ABPM, 186 of 415 participants were confirmed to be hypertensive, with crude prevalence of 15.6% (95% CI 9.4-23.1%) and age-standardized prevalence of 17.1% (95% CI 11.0-24.4%). Age-standardized prevalence of masked and white coat hypertension were 7.6% (95% CI 2.8-13.7%) and 3.8% (95% CI 1.7-6.1%), respectively. The sensitivity and specificity of screening BP measurements were 80% (95% CI 73-86%) and 84% (95% CI 79-88%), respectively. BP indices and validity measures showed strong age-related trends. CONCLUSIONS Screening BP measurement significantly overestimated hypertension prevalence while failing to identify ≈50% of true hypertension diagnosed by ABPM. Our findings suggest significant clinical and epidemiological benefits of ABPM use for diagnosing hypertension in Kenyan adults.
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Affiliation(s)
- Anthony O Etyang
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Ben Warne
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Kenneth Munge
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Evasius Bauni
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | | | - Liam Smeeth
- London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - J Anthony G Scott
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- London School of Hygiene and Tropical Medicine, London, United Kingdom
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Abstract
Rationale: Several studies have demonstrated links between infectious diseases and cardiovascular conditions. Malaria and hypertension are widespread in many low- and middle-income countries, but the possible link between them has not been considered. Objective: In this article, we outline the basis for a possible link between malaria and hypertension and discuss how the hypothesis could be confirmed or refuted. Methods and Results: We reviewed published literature on factors associated with hypertension and checked whether any of these were also associated with malaria. We then considered various study designs that could be used to test the hypothesis. Malaria causes low birth weight, malnutrition, and inflammation, all of which are associated with hypertension in high-income countries. The hypothetical link between malaria and hypertension can be tested through the use of ecological, cohort, or Mendelian randomization studies, each of which poses specific challenges. Conclusions: Confirmation of the existence of a causative link with malaria would be a paradigm shift in efforts to prevent and control hypertension and would stimulate wider research on the links between infectious and noncommunicable disease.
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Affiliation(s)
- Anthony O Etyang
- From the Department of Epidemiology and Demography, KEMRI-Wellcome Trust Research Program, Kilifi, Kenya (A.O.E., J.A.G.S.); Department of Infectious Disease Epidemiology (A.O.E., J.A.G.S.), and Department of Non-Communicable Disease Epidemiology (L.S.), London School of Hygiene and Tropical Medicine, London, United Kingdom; and Cardiovascular Medicine Group, Division of Diabetes and Nutritional Sciences, King's College, London, United Kingdom (J.K.C.).
| | - Liam Smeeth
- From the Department of Epidemiology and Demography, KEMRI-Wellcome Trust Research Program, Kilifi, Kenya (A.O.E., J.A.G.S.); Department of Infectious Disease Epidemiology (A.O.E., J.A.G.S.), and Department of Non-Communicable Disease Epidemiology (L.S.), London School of Hygiene and Tropical Medicine, London, United Kingdom; and Cardiovascular Medicine Group, Division of Diabetes and Nutritional Sciences, King's College, London, United Kingdom (J.K.C.)
| | - J Kennedy Cruickshank
- From the Department of Epidemiology and Demography, KEMRI-Wellcome Trust Research Program, Kilifi, Kenya (A.O.E., J.A.G.S.); Department of Infectious Disease Epidemiology (A.O.E., J.A.G.S.), and Department of Non-Communicable Disease Epidemiology (L.S.), London School of Hygiene and Tropical Medicine, London, United Kingdom; and Cardiovascular Medicine Group, Division of Diabetes and Nutritional Sciences, King's College, London, United Kingdom (J.K.C.)
| | - J Anthony G Scott
- From the Department of Epidemiology and Demography, KEMRI-Wellcome Trust Research Program, Kilifi, Kenya (A.O.E., J.A.G.S.); Department of Infectious Disease Epidemiology (A.O.E., J.A.G.S.), and Department of Non-Communicable Disease Epidemiology (L.S.), London School of Hygiene and Tropical Medicine, London, United Kingdom; and Cardiovascular Medicine Group, Division of Diabetes and Nutritional Sciences, King's College, London, United Kingdom (J.K.C.)
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23
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Muthumbi E, Morpeth SC, Ooko M, Mwanzu A, Mwarumba S, Mturi N, Etyang AO, Berkley JA, Williams TN, Kariuki S, Scott JAG. Invasive Salmonellosis in Kilifi, Kenya. Clin Infect Dis 2015; 61 Suppl 4:S290-301. [PMID: 26449944 PMCID: PMC4596936 DOI: 10.1093/cid/civ737] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Invasive salmonelloses are a major cause of morbidity and mortality in Africa, but the incidence and case fatality of each disease vary markedly by region. We aimed to describe the incidence, clinical characteristics, and antimicrobial susceptibility patterns of invasive salmonelloses among children and adults in Kilifi, Kenya. METHODS We analyzed integrated clinical and laboratory records for patients presenting to the Kilifi County Hospital between 1998 and 2014. We calculated incidence, and summarized clinical features and multidrug resistance. RESULTS Nontyphoidal Salmonella (NTS) accounted for 10.8% and 5.8% of bacteremia cases in children and adults, respectively, while Salmonella Typhi accounted for 0.5% and 2.1%, respectively. Among 351 NTS isolates serotyped, 160 (45.6%) were Salmonella Enteritidis and 152 (43.3%) were Salmonella Typhimurium. The incidence of NTS in children aged <5 years was 36.6 per 100 000 person-years, being highest in infants aged <7 days (174/100 000 person-years). The overall incidence of NTS in children varied markedly by location and declined significantly during the study period; the pattern of dominance of the NTS serotypes also shifted from Salmonella Enteritidis to Salmonella Typhimurium. Risk factors for invasive NTS disease were human immunodeficiency virus infection, malaria, and malnutrition; the case fatality ratio was 22.1% (71/321) in children aged <5 years and 36.7% (11/30) in adults. Multidrug resistance was present in 23.9% (84/351) of NTS isolates and 46.2% (12/26) of Salmonella Typhi isolates. CONCLUSIONS In Kilifi, the incidence of invasive NTS was high, especially among newborn infants, but typhoid fever was uncommon. NTS remains an important cause of bacteremia in children <5 years of age.
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Affiliation(s)
- Esther Muthumbi
- Kenya Medical Research Institute–Wellcome Trust Research Programme, Kilifi
| | - Susan C. Morpeth
- Kenya Medical Research Institute–Wellcome Trust Research Programme, Kilifi
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine
| | - Michael Ooko
- Kenya Medical Research Institute–Wellcome Trust Research Programme, Kilifi
| | - Alfred Mwanzu
- Kenya Medical Research Institute–Wellcome Trust Research Programme, Kilifi
| | - Salim Mwarumba
- Kenya Medical Research Institute–Wellcome Trust Research Programme, Kilifi
| | - Neema Mturi
- Kenya Medical Research Institute–Wellcome Trust Research Programme, Kilifi
| | - Anthony O. Etyang
- Kenya Medical Research Institute–Wellcome Trust Research Programme, Kilifi
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine
| | - James A. Berkley
- Kenya Medical Research Institute–Wellcome Trust Research Programme, Kilifi
- Nuffield Department of Clinical Medicine, Oxford University, United Kingdom
| | - Thomas N. Williams
- Kenya Medical Research Institute–Wellcome Trust Research Programme, Kilifi
- Nuffield Department of Clinical Medicine, Oxford University, United Kingdom
| | - Samuel Kariuki
- Centre for Microbiological Research, Kenya Medical Research Institute, Nairobi
| | - J. Anthony G. Scott
- Kenya Medical Research Institute–Wellcome Trust Research Programme, Kilifi
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine
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24
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Etyang AO, Munge K, Bunyasi EW, Matata L, Ndila C, Kapesa S, Owiti M, Khandwalla I, Brent AJ, Tsofa B, Kabibu P, Morpeth S, Bauni E, Otiende M, Ojal J, Ayieko P, Knoll MD, Smeeth L, Williams TN, Griffiths UK, Scott JAG. Burden of disease in adults admitted to hospital in a rural region of coastal Kenya: an analysis of data from linked clinical and demographic surveillance systems. Lancet Glob Health 2015; 2:e216-24. [PMID: 24782954 PMCID: PMC3986034 DOI: 10.1016/s2214-109x(14)70023-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Background Estimates of the burden of disease in adults in sub-Saharan Africa largely rely on models of sparse data. We aimed to measure the burden of disease in adults living in a rural area of coastal Kenya with use of linked clinical and demographic surveillance data. Methods We used data from 18 712 adults admitted to Kilifi District Hospital (Kilifi, Kenya) between Jan 1, 2007, and Dec 31, 2012, linked to 790 635 person-years of observation within the Kilifi Health and Demographic Surveillance System, to establish the rates and major causes of admission to hospital. These data were also used to model disease-specific disability-adjusted life-years lost in the population. We used geographical mapping software to calculate admission rates stratified by distance from the hospital. Findings The main causes of admission to hospital in women living within 5 km of the hospital were infectious and parasitic diseases (303 per 100 000 person-years of observation), pregnancy-related disorders (239 per 100 000 person-years of observation), and circulatory illnesses (105 per 100 000 person-years of observation). Leading causes of hospital admission in men living within 5 km of the hospital were infectious and parasitic diseases (169 per 100 000 person-years of observation), injuries (135 per 100 000 person-years of observation), and digestive system disorders (112 per 100 000 person-years of observation). HIV-related diseases were the leading cause of disability-adjusted life-years lost (2050 per 100 000 person-years of observation), followed by non-communicable diseases (741 per 100 000 person-years of observation). For every 5 km increase in distance from the hospital, all-cause admission rates decreased by 11% (95% CI 7–14) in men and 20% (17–23) in women. The magnitude of this decline was highest for endocrine disorders in women (35%; 95% CI 22–46) and neoplasms in men (30%; 9–45). Interpretation Adults in rural Kenya face a combined burden of infectious diseases, pregnancy-related disorders, cardiovascular illnesses, and injuries. Disease burden estimates based on hospital data are affected by distance from the hospital, and the amount of underestimation of disease burden differs by both disease and sex. Funding The Wellcome Trust, GAVI Alliance.
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Affiliation(s)
- Anthony O Etyang
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Kilifi District Hospital, Kilifi, Kenya
- Correspondence to: Dr Anthony O Etyang, KEMRI-Wellcome Trust Research Programme, PO Box 230-80108, Kilifi, Kenya
| | - Kenneth Munge
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Kilifi District Hospital, Kilifi, Kenya
| | - Erick W Bunyasi
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Kilifi District Hospital, Kilifi, Kenya
| | - Lena Matata
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Kilifi District Hospital, Kilifi, Kenya
| | | | - Sailoki Kapesa
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Kilifi District Hospital, Kilifi, Kenya
| | | | | | - Andrew J Brent
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Kilifi District Hospital, Kilifi, Kenya
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
- Imperial College, London, UK
| | - Benjamin Tsofa
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Kilifi District Hospital, Kilifi, Kenya
| | | | - Susan Morpeth
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Kilifi District Hospital, Kilifi, Kenya
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - Evasius Bauni
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- INDEPTH Network, Accra, Ghana
| | - Mark Otiende
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - John Ojal
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Philip Ayieko
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
| | - Maria D Knoll
- Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Liam Smeeth
- London School of Hygiene & Tropical Medicine, London, UK
| | - Thomas N Williams
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Kilifi District Hospital, Kilifi, Kenya
- INDEPTH Network, Accra, Ghana
- Imperial College, London, UK
| | | | - J Anthony G Scott
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Kilifi District Hospital, Kilifi, Kenya
- London School of Hygiene & Tropical Medicine, London, UK
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
- INDEPTH Network, Accra, Ghana
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25
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Etyang AO, Scott JAG. Medical causes of admissions to hospital among adults in Africa: a systematic review. Glob Health Action 2013; 6:1-14. [PMID: 23336616 PMCID: PMC3541514 DOI: 10.3402/gha.v6i0.19090] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2012] [Revised: 12/10/2012] [Accepted: 12/11/2012] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Despite the publication of several studies on the subject, there is significant uncertainty regarding the burden of disease among adults in sub-Saharan Africa (sSA). OBJECTIVES To describe the breadth of available data regarding causes of admission to hospital, to systematically analyze the methodological quality of these studies, and to provide recommendations for future research. DESIGN We performed a systematic online and hand-based search for articles describing patterns of medical illnesses in patients admitted to hospitals in sSA between 1950 and 2010. Diseases were grouped into bodily systems using International Classification of Disease (ICD) guidelines. We compared the proportions of admissions and deaths by diagnostic category using χ2. RESULTS Thirty articles, describing 86,307 admissions and 9,695 deaths, met the inclusion criteria. The leading causes of admission were infectious and parasitic diseases (19.8%, 95% confidence interval [CI] 19.6-20.1), respiratory (16.2%, 95% CI 16.0-16.5) and circulatory (11.3%, 95% CI 11.1-11.5) illnesses. The leading causes of death were infectious and parasitic (17.1%, 95% CI 16.4-17.9), circulatory (16%, 95% CI 15.3-16.8) and digestive (16.2%, 95% CI 15.4-16.9). Circulatory diseases increased from 3.9% of all admissions in 1950-59 to 19.9% in 2000-2010 (RR 5.1, 95% CI 4.5-5.8, test for trend p<0.00005). The most prevalent methodological deficiencies, present in two-thirds of studies, were failures to use standardized case definitions and ICD guidelines for classifying illnesses. CONCLUSIONS Cardiovascular and infectious diseases are currently the leading causes of admissions and in-hospital deaths in sSA. Methodological deficiencies have limited the usefulness of previous studies in defining national patterns of disease in adults. As African countries pass through demographic and health transition, they need to significantly invest in clinical research capacity to provide an accurate description of the disease burden among adults for public health policy.
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Affiliation(s)
- Anthony O Etyang
- Department of Epidemiology and Demography, Kenya Medical Research Institute/Wellcome Trust Research Programme, Kilifi, Kenya.
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Etyang AO, Amayo EO, Bhatt SM, Wamola IA, Maritim MC. Comparison of bedside inoculation of culture media with conventional cerebrospinal fluid culture method in patients with bacterial meningitis. ACTA ACUST UNITED AC 2011; 86:476-9. [PMID: 21650071 DOI: 10.4314/eamj.v86i10.54970] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND The yield of bacterial cultures from cerebrospinal fluid (CSF) at Kenyatta National Hospital (KNH) is very low. Bedside inoculation of culture media with CSF may improve yields. OBJECTIVE To compare the culture yield of CSF inoculated onto culture medium at the bedside to that of CSF inoculated onto culture medium in the microbiology laboratory. DESIGN Cross-sectional comparative study. SETTING Accident and Emergency Department and medical wards at Kenyatta National Hospital. SUBJECTS Cerebrospinal fluid from patients at KNH with a clinical diagnosis of acute meningitis. RESULTS Two hundred and twenty CSF specimens were obtained during a four month period. S. pneumaniae was isolated from 24 CSF samples and H. influenzae from one. Bacterial cultures were positive in 25 (11.4%, 95% CI 7.0-15.6%) samples inoculated at the bedside and 23 (10.5%, 95% CI 6.5-14.5%) samples inoculated at the laboratory. Bacteria were isolated 5 hours earlier in samples inoculated at the bedside (95% CI 4.34-6.86 hrs, p < 0.05). Four per cent of S. pneumaniae isolates were resistant to crystalline penicillin. CONCLUSION There was no significant difference in culture yield after bedside inoculation of culture media with CSF compared to traditional CSF culture method. Bedside inoculation of culture media with CSF resulted in faster time to positive culture.
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Affiliation(s)
- A O Etyang
- Kenyatta National Hospital, P.O. Box 20723-00202, Nairobi, Kenya
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