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Doherty K, Dula D, Chirwa A, Nsomba E, Nkhoma VS, Toto N, Chikaonda T, Kamng'ona R, Phiri J, Reiné J, Ndaferankhande J, Makhaza L, Banda P, Jambo K, Ferreira DM, Gordon SB. Experimental pneumococcal carriage in people living with HIV in Malawi: the first controlled human infection model in a key at-risk population. Wellcome Open Res 2024; 9:2. [PMID: 38362541 PMCID: PMC10864820 DOI: 10.12688/wellcomeopenres.19949.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/03/2023] [Indexed: 02/17/2024] Open
Abstract
Background: As well as suffering a high burden of pneumococcal disease people living with HIV (PLHIV) may contribute to community transmission in sub-Saharan African (sSA) settings. Pneumococcal vaccination is not currently offered to PLHIV in sSA but may prevent disease and reduce transmission. More evidence of vaccine effectiveness against carriage in PLHIV is needed. An Experimental Human Pneumococcal Carriage model (EHPC) has been safely and acceptably used in healthy adults in Malawi to evaluate pneumococcal vaccines against carriage and to identify immune correlates of protection from carriage. This study will establish the same model in PLHIV and will be the first controlled human infection model (CHIM) in this key population. Methods: Healthy participants with and without HIV will be inoculated intranasally with Streptococcus pneumoniae serotype 6B. Sequential cohorts will be challenged with increasing doses to determine the optimal safe challenge dose to establish experimental carriage. Nasal fluid, nasal mucosal, and blood samples will be taken before inoculation and on days 2, 7, 14, and 21 following inoculation to measure pneumococcal carriage density and identify immune correlates of protection from carriage. The vast majority of natural pneumococcal carriage events in PLHIV do not result in invasive disease and no invasive disease is expected in this study. However, robust participant safety monitoring is designed to identify signs of invasive disease early should they develop, and to implement treatment immediately. Participants will complete a Likert-style questionnaire at study-end to establish acceptability. Interpretations: We expect the EHPC model to be safely and acceptably implemented in PLHIV. The CHIM can then be used to accelerate pneumococcal vaccine evaluations in this population, and an evidence-based pneumococcal vaccination policy for PLHIV in sSA.
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Affiliation(s)
- Klara Doherty
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Southern Region, Malawi
- Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Dingase Dula
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Southern Region, Malawi
| | - Anthony Chirwa
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Southern Region, Malawi
| | - Edna Nsomba
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Southern Region, Malawi
| | - Vitumbiko S. Nkhoma
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Southern Region, Malawi
| | - Neema Toto
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Southern Region, Malawi
| | - Tarsizio Chikaonda
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Southern Region, Malawi
| | - Raphael Kamng'ona
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Southern Region, Malawi
| | - Joseph Phiri
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Southern Region, Malawi
| | - Jesús Reiné
- Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
- Oxford Vaccine Group, University of Oxford, Oxford, England, UK
| | - John Ndaferankhande
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Southern Region, Malawi
| | - Lumbani Makhaza
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Southern Region, Malawi
| | - Peter Banda
- Kamuzu University of Health Sciences, Blantyre, Malawi
| | - Kondwani Jambo
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Southern Region, Malawi
- Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
| | - Daniela M Ferreira
- Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
- Oxford Vaccine Group, University of Oxford, Oxford, England, UK
| | - Stephen B Gordon
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Southern Region, Malawi
- Liverpool School of Tropical Medicine, Liverpool, L3 5QA, UK
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2
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Tsirigotaki M, Galanakis E. Impact of vaccines on Staphylococcus aureus colonization: A systematic review and meta-analysis. Vaccine 2023; 41:6478-6487. [PMID: 37777451 DOI: 10.1016/j.vaccine.2023.09.034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Revised: 08/17/2023] [Accepted: 09/19/2023] [Indexed: 10/02/2023]
Abstract
BACKGROUND Concerns regarding vaccine effects on microbial ecology have led to interest in the non-targeted effects of vaccinations. OBJECTIVES To systematically review the literature related to the impact of vaccines on S. aureus carriage. METHODS We conducted a systematic search of MEDLINE, Scopus and clinical trials.gov for studies that assessed vaccine effects on S. aureus carriage in children and adults using predefined inclusion and exclusion criteria. Generic inverse variance meta-analysis was done using random-effects models. RESULTS Of 1,686 studies screened, 34 were eligible for inclusion, of which 22 were observational and 12 randomized controlled studies (RCTs). 88.2% (30/34) provided data on pneumococcal conjugate vaccines (PCV), 23.5% on influenza vaccines (8/34), 6% on other vaccines (2/34) and 20.6% on more than one vaccine (7/34). Most studies tested nasopharyngeal specimens (82.3%, 28/34). Among children aged more than 18-24 months, evidence suggested no effect of PCV on S. aureus colonization [2 RCTs, pooled OR 1.09 (95% CI 0.94-1.25), p 0.25; 7 observational studies, pooled OR: 1.02 (95% CI 0.83-1.25), p 0.86]. A transient increase in S. aureus carriage in PCV-vaccinated infants 9-15 months was shown [2 RCTs, pooled OR 1.11 (95% CI 1.00-1.23), p 0.06; 4 observational studies, pooled OR 1.64 (95% CI 1.00-2.68), p 0.05]. A reduction in S. aureus carriage was observed after influenza vaccination [4 observational studies; OR 0.85 (95% CI 0.78-0.94), p 0.0001]. Based on the Grading of Recommendations Assessment, Development and Evaluation, the quality of evidence was considered low for randomized and very low for non-randomized trials. CONCLUSION Evidence did not suggest long-term effects of pneumococcal vaccinations on S. aureus nasopharyngeal carriage in children, however transient niche changes may occur in infants. Influenza vaccination was related to decreased rates of S. aureus carriage. Data regarding other vaccines is scarce. Further research and ongoing surveillance are needed to monitor colonization changes.
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Wolf AS, Mitsi E, Jones S, Jochems SP, Roalfe L, Thindwa D, Meiring JE, Msefula J, Bonomali F, Makhaza Jere T, Mbewe M, Collins AM, Gordon SB, Gordon MA, Ferreira DM, French N, Goldblatt D, Heyderman RS, Swarthout TD. Quality of antibody responses by adults and young children to 13-valent pneumococcal conjugate vaccination and Streptococcus pneumoniae colonisation. Vaccine 2022; 40:7201-7210. [PMID: 36210249 PMCID: PMC10615833 DOI: 10.1016/j.vaccine.2022.09.069] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 09/15/2022] [Accepted: 09/22/2022] [Indexed: 11/18/2022]
Abstract
Childhood pneumococcal conjugate vaccine (PCV) protects against invasive pneumococcal disease caused by vaccine-serotype (VT) Streptococcus pneumoniae by generating opsonophagocytic anti-capsular antibodies, but how vaccination protects against and reduces VT carriage is less well understood. Using serological samples from PCV-vaccinated Malawian individuals and a UK human challenge model, we explored whether antibody quality (IgG subclass, opsonophagocytic killing, and avidity) is associated with protection from carriage. Following experimental challenge of adults with S. pneumoniae serotype 6B, 3/21 PCV13-vaccinees were colonised with pneumococcus compared to 12/24 hepatitis A-vaccinated controls; PCV13-vaccination induced serotype-specific IgG, IgG1, and IgG2, and strong opsonophagocytic responses. However, there was no clear relationship between antibody quality and protection from carriage or carriage intensity after vaccination. Similarly, among PCV13-vaccinated Malawian infants there was no relationship between serotype-specific antibody titre or quality and carriage through exposure to circulating serotypes. Although opsonophagocytic responses were low in infants, antibody titre and avidity to circulating serotypes 19F and 6A were maintained or increased with age. These data suggest a complex relationship between antibody-mediated immunity and pneumococcal carriage, and that PCV13-driven antibody quality may mature with age and exposure.
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Affiliation(s)
- Asia-Sophia Wolf
- NIHR Global Health Mucosal Pathogens Research Unit, Division of Infection and Immunity, University College London, London, UK
| | - Elena Mitsi
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Scott Jones
- Great Ormond Street Institute of Child Health, University College London, London, UK
| | - Simon P. Jochems
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Lucy Roalfe
- Great Ormond Street Institute of Child Health, University College London, London, UK
| | - Deus Thindwa
- Malawi-Liverpool-Wellcome Programme, Blantyre, Malawi
- Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK
| | - James E. Meiring
- Malawi-Liverpool-Wellcome Programme, Blantyre, Malawi
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, UK
| | | | | | | | - Maurice Mbewe
- Malawi-Liverpool-Wellcome Programme, Blantyre, Malawi
| | - Andrea M. Collins
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
- Liverpool University Hospitals Foundation Trust, Liverpool, UK
| | | | - Melita A. Gordon
- Malawi-Liverpool-Wellcome Programme, Blantyre, Malawi
- Kamuzu University of Health Sciences, Blantyre, Malawi
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
| | - Daniela M. Ferreira
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Neil French
- Malawi-Liverpool-Wellcome Programme, Blantyre, Malawi
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK
| | - David Goldblatt
- Great Ormond Street Institute of Child Health, University College London, London, UK
| | - Robert S. Heyderman
- NIHR Global Health Mucosal Pathogens Research Unit, Division of Infection and Immunity, University College London, London, UK
| | - Todd D. Swarthout
- NIHR Global Health Mucosal Pathogens Research Unit, Division of Infection and Immunity, University College London, London, UK
- Malawi-Liverpool-Wellcome Programme, Blantyre, Malawi
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4
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Nunes MC, Moreira M, Koen A, van Niekerk N, Jose L, Cutland CL, François N, Schoonbroodt S, Ruiz-Guiñazú J, Yarzabal JP, Borys D, Schuerman L, Madhi SA. Bacterial nasopharyngeal carriage following infant immunization with pneumococcal conjugate vaccines according to a 2+1 schedule in children in South Africa: an exploratory analysis of two clinical trials. Expert Rev Vaccines 2020; 19:1177-1189. [PMID: 33245004 DOI: 10.1080/14760584.2020.1853533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Background: We evaluated bacterial nasopharyngeal carriage (NPC) prevalence and cumulative acquisition following 7-valent pneumococcal conjugate vaccine (PCV7) or pneumococcal non-typeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV) administration. Methods: Participants were children from two clinical trials in a South African center who received PCV7 (n = 250) or PHiD-CV (n = 100) at ~6 weeks, ~14 weeks, and ~9-10 months of age, and were enrolled between Dec2009-Apr2010 and Mar2009-May2010 in the PCV7 and PHiD-CV studies, respectively. Sample collection, most microbiological assessments, and data re-analysis methods were identical. Results: NPC prevalence of any pneumococcal serotype was 18.5% and 17.0% at pre-vaccination, and 63.1% and 67.3% in 24-27 month-old children among PCV7 and PHiD-CV recipients, respectively. In 24-27 month-old children, 96.1% and 99.0% of PCV7 and PHiD-CV recipients had acquired ≥1 pneumococcal serotype, 53.7% and 62.9% ≥1 PCV7 serotype, 1.5%, and 3.1% ≥1 of serotypes 1, 5 or 7F, 23.2% and 19.6% serotype 6A, 23.2% and 21.7% serotype 19A, 88.7%, and 91.0% H. influenzae, and 50.3% and 62.9% Staphylococcus aureus, respectively. Conclusions: This analysis of two concurrent clinical trials did not reveal differences in bacterial NPC prevalence or acquisition in PCV7- and PHiD-CV-vaccinated children. Trial registration: South African National Clinical Trial Register (NHREC DOH-27-0511-299); ClinicalTrials.gov (NCT00829010).
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Affiliation(s)
- Marta C Nunes
- Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand , Johannesburg, South Africa.,Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Sciences, University of the Witwatersrand , Johannesburg, South Africa
| | | | - Anthonet Koen
- Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand , Johannesburg, South Africa.,Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Sciences, University of the Witwatersrand , Johannesburg, South Africa
| | - Nadia van Niekerk
- Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand , Johannesburg, South Africa.,Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Sciences, University of the Witwatersrand , Johannesburg, South Africa
| | - Lisa Jose
- Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand , Johannesburg, South Africa.,Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Sciences, University of the Witwatersrand , Johannesburg, South Africa
| | - Clare L Cutland
- Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand , Johannesburg, South Africa.,Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Sciences, University of the Witwatersrand , Johannesburg, South Africa
| | | | | | | | | | | | | | - Shabir A Madhi
- Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand , Johannesburg, South Africa.,Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, Faculty of Health Sciences, University of the Witwatersrand , Johannesburg, South Africa
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5
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Swarthout TD, Fronterre C, Lourenço J, Obolski U, Gori A, Bar-Zeev N, Everett D, Kamng'ona AW, Mwalukomo TS, Mataya AA, Mwansambo C, Banda M, Gupta S, Diggle P, French N, Heyderman RS. High residual carriage of vaccine-serotype Streptococcus pneumoniae after introduction of pneumococcal conjugate vaccine in Malawi. Nat Commun 2020; 11:2222. [PMID: 32376860 PMCID: PMC7203201 DOI: 10.1038/s41467-020-15786-9] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Accepted: 03/28/2020] [Indexed: 12/22/2022] Open
Abstract
There are concerns that pneumococcal conjugate vaccines (PCVs) in sub-Saharan Africa sub-optimally interrupt Streptococcus pneumoniae vaccine-serotype (VT) carriage and transmission. Here we assess PCV carriage using rolling, prospective nasopharyngeal carriage surveys between 2015 and 2018, 3.6–7.1 years after Malawi’s 2011 PCV13 introduction. Carriage decay rate is analysed using non-linear regression. Despite evidence of reduction in VT carriage over the study period, there is high persistent residual carriage. This includes among PCV-vaccinated children 3–5-year-old (16.1% relative reduction from 19.9% to 16.7%); PCV-unvaccinated children 6–8-year-old (40.5% reduction from 26.4% to 15.7%); HIV-infected adults 18-40-years-old on antiretroviral therapy (41.4% reduction from 15.2% to 8.9%). VT carriage prevalence half-life is similar among PCV-vaccinated and PCV-unvaccinated children (3.26 and 3.34 years, respectively). Compared with high-income settings, there is high residual VT carriage 3.6–7.1 years after PCV introduction. Rigorous evaluation of strategies to augment vaccine-induced control of carriage, including alternative schedules and catch-up campaigns, is required. Impact of pneumococcal conjugate vaccines (PCV) in controlling carriage needs to be evaluated to inform vaccine policy. Here, Swarthout et al. show in a prospective rolling cross-sectional study in Malawi a high residual prevalence of vaccine-serotype S. pneumoniae 7 years after PCV introduction.
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Affiliation(s)
- Todd D Swarthout
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi. .,NIHR Global Health Research Unit on Mucosal Pathogens, Division of Infection and Immunity, University College London, London, UK. .,Clinical Sciences Department, Liverpool School of Tropical Medicine, Liverpool, UK.
| | - Claudio Fronterre
- CHICAS, Lancaster Medical School, Lancaster University, Lancaster, UK
| | - José Lourenço
- Department of Zoology, University of Oxford, Oxford, UK
| | - Uri Obolski
- School of Public Health, Tel Aviv University, Tel Aviv, Israel.,Porter School of the Environment and Earth Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Andrea Gori
- NIHR Global Health Research Unit on Mucosal Pathogens, Division of Infection and Immunity, University College London, London, UK
| | - Naor Bar-Zeev
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi.,International Vaccine Access Center, Department of International Health, Johns Hopkins University, Baltimore, USA
| | - Dean Everett
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi.,The Queens Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - Arox W Kamng'ona
- Department of Biomedical Sciences, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Thandie S Mwalukomo
- Department of Medicine, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Andrew A Mataya
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | | | | | - Sunetra Gupta
- Department of Zoology, University of Oxford, Oxford, UK
| | - Peter Diggle
- CHICAS, Lancaster Medical School, Lancaster University, Lancaster, UK
| | - Neil French
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi.,Centre for Global Vaccine Research, Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
| | - Robert S Heyderman
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi.,NIHR Global Health Research Unit on Mucosal Pathogens, Division of Infection and Immunity, University College London, London, UK
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6
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Impact of HIV status and vaccination schedule on bacterial nasopharyngeal carriage following infant immunisation with the pneumococcal non-typeable Haemophilus influenzae protein D conjugate vaccine in South Africa. Vaccine 2020; 38:2350-2360. [PMID: 32035706 DOI: 10.1016/j.vaccine.2020.01.062] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Revised: 01/20/2020] [Accepted: 01/21/2020] [Indexed: 11/21/2022]
Abstract
BACKGROUND Nasopharyngeal carriage (NPC) of Streptococcus pneumoniae is a precondition for pneumococcal disease and a source of transmission. This trial evaluated NPC of S. pneumoniae and other pathogens post-vaccination with the pneumococcal non-typeable Haemophilus influenzae (NTHi) protein D conjugate vaccine (PHiD-CV) in human immunodeficiency virus (HIV)-infected (HIV+), HIV-exposed-uninfected (HEU), and HIV-unexposed-uninfected (HUU) South African children. METHODS In this phase III, open, single-centre, controlled study (ClinicalTrials.gov: NCT00829010), 484 children were stratified by HIV status: 83 HIV+, 101 HEU, and 300 HUU. HIV+ and HEU children received a 3 + 1 PHiD-CV vaccination schedule: primary vaccination, age 6/10/14 weeks, and booster dose, age 9-10 months. HUU infants were randomised (1:1:1) to 3-dose priming and booster (HUU/3+1); 3-dose priming without booster (HUU/3+0); or 2-dose priming and booster (HUU/2+1). Bacterial NPC was assessed 8 times up to 24-27 months of age. RESULTS Overall pneumococcal carriage rates were similar across 3+1 groups irrespective of HIV status; trends towards higher carriage rates in the HIV+ than HEU and HUU/3+1 groups were observed at 24-27 months of age. In HUU children, carriage of any pneumococcal serotype was similar for the three different dosing schedules at all timepoints; carriage of vaccine-type pneumococci tended to be lower at 16-19 months and 24-27 months of age in children who had received a booster dose (HUU/2+1 and HUU/3+1 groups) than in the HUU/3+0 group. Carriage rates of NTHi, Staphylococcus aureus and Moraxella catarrhalis were comparable between all groups. CONCLUSIONS HIV infection or exposure did not seem to alter the effect of PHiD-CV on pneumococcal NPC in children during their first 2 years of life. NPC prevalence of vaccine-type pneumococci following vaccination series tended to be lower in children who had received a booster dose in comparison to those who had not.
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7
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Tin Tin Htar M, Sings HL, Syrochkina M, Taysi B, Hilton B, Schmitt HJ, Gessner BD, Jodar L. The impact of pneumococcal conjugate vaccines on serotype 19A nasopharyngeal carriage. Expert Rev Vaccines 2019; 18:1243-1270. [DOI: 10.1080/14760584.2019.1675521] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Affiliation(s)
| | - Heather L. Sings
- Vaccines Medical Development and Scientific and Clinical Affairs, Pfizer Inc, Collegeville, PA, USA
| | - Maria Syrochkina
- Vaccines Medical Development and Scientific and Clinical Affairs, Pfizer Inc, Moscow, Russia
| | - Bulent Taysi
- Vaccines Medical Development and Scientific and Clinical Affairs, Pfizer Inc, Istanbul, Turkey
| | - Betsy Hilton
- Vaccines Medical Development and Scientific and Clinical Affairs, Pfizer Inc, Collegeville, PA, USA
| | - Heinz-Josef Schmitt
- Vaccines Medical Development and Scientific and Clinical Affairs, Pfizer Inc, Collegeville, PA, USA
| | - Bradford D. Gessner
- Vaccines Medical Development and Scientific and Clinical Affairs, Pfizer Inc, Collegeville, PA, USA
| | - Luis Jodar
- Vaccines Medical Development and Scientific and Clinical Affairs, Pfizer Inc, Collegeville, PA, USA
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8
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Lourenço J, Obolski U, Swarthout TD, Gori A, Bar-Zeev N, Everett D, Kamng'ona AW, Mwalukomo TS, Mataya AA, Mwansambo C, Banda M, Gupta S, French N, Heyderman RS. Determinants of high residual post-PCV13 pneumococcal vaccine-type carriage in Blantyre, Malawi: a modelling study. BMC Med 2019; 17:219. [PMID: 31801542 PMCID: PMC6894346 DOI: 10.1186/s12916-019-1450-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 10/24/2019] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND In November 2011, Malawi introduced the 13-valent pneumococcal conjugate vaccine (PCV13) into the routine infant schedule. Four to 7 years after introduction (2015-2018), rolling prospective nasopharyngeal carriage surveys were performed in the city of Blantyre. Carriage of Streptococcus pneumoniae vaccine serotypes (VT) remained higher than reported in high-income countries, and impact was asymmetric across age groups. METHODS A dynamic transmission model was fit to survey data using a Bayesian Markov-chain Monte Carlo approach, to obtain insights into the determinants of post-PCV13 age-specific VT carriage. RESULTS Accumulation of naturally acquired immunity with age and age-specific transmission potential were both key to reproducing the observed data. VT carriage reduction peaked sequentially over time, earlier in younger and later in older age groups. Estimated vaccine efficacy (protection against carriage) was 66.87% (95% CI 50.49-82.26%), similar to previous estimates. Ten-year projected vaccine impact (VT carriage reduction) among 0-9 years old was lower than observed in other settings, at 76.23% (CI 95% 68.02-81.96%), with sensitivity analyses demonstrating this to be mainly driven by a high local force of infection. CONCLUSIONS There are both vaccine-related and host-related determinants of post-PCV13 pneumococcal VT transmission in Blantyre with vaccine impact determined by an age-specific, local force of infection. These findings are likely to be generalisable to other Sub-Saharan African countries in which PCV impact on carriage (and therefore herd protection) has been lower than desired, and have implications for the interpretation of post-PCV carriage studies and future vaccination programs.
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Affiliation(s)
- J Lourenço
- Department of Zoology, University of Oxford, Oxford, UK.
| | - U Obolski
- School of Public Health, Tel Aviv University, Tel Aviv, Israel.,Porter School of the Environment and Earth Sciences, Tel Aviv University, Tel Aviv, Israel
| | - T D Swarthout
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi.,Clinical Sciences Department, Liverpool School of Tropical Medicine, Liverpool, UK
| | - A Gori
- NIHR Mucosal Pathogens Research Unit, Division of Infection & Immunity, University College London, London, UK
| | - N Bar-Zeev
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi.,Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA
| | - D Everett
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi.,The Queens Medical Research Institute, University of Edinburgh, Edinburgh, UK
| | - A W Kamng'ona
- Department of Biomedical Sciences, College of Medicine, University of Malawi, Blantyre, Malawi
| | - T S Mwalukomo
- Department of Medicine, College of Medicine, University of Malawi, Blantyre, Malawi
| | - A A Mataya
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | | | - M Banda
- Ministry of Education, Blantyre, Malawi
| | - S Gupta
- Department of Zoology, University of Oxford, Oxford, UK
| | - N French
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi.,Centre for Global Vaccine Research, Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
| | - R S Heyderman
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi.,NIHR Mucosal Pathogens Research Unit, Division of Infection & Immunity, University College London, London, UK
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9
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Newton C, Maake H, Maluleka C, Mda S. Pneumococcus nasopharyngeal carriage in children attending an academic hospital in Pretoria, South Africa, after the introduction of pneumococcal vaccine. S Afr J Infect Dis 2019; 34:112. [PMID: 34485453 PMCID: PMC8378010 DOI: 10.4102/sajid.v34i1.112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Accepted: 07/24/2019] [Indexed: 11/06/2022] Open
Abstract
Background In 2009, pneumococcal conjugate vaccine was introduced in South Africa. However, there are concerns that this could lead to an increase in colonisation of non-vaccine serotypes (serotype replacement). Methods In a cross-sectional study, 350 children aged 1 month to 14 years were enrolled at Dr George Mukhari Academic Hospital from December 2015 to April 2016. We assessed the prevalence of nasopharyngeal colonisation with pneumococcus and characterised the serotypes found. Results The median age of the cohort was 33.7 months (interquartile range 16.27–69.5 months), with 20% being < 1 year. A total of 21% of the children were diagnosed with pneumococcal-related conditions; among these, pneumonia was the most common condition. Less than half (43%) of the participants were fully immunised. Forty-six (13%) of the children were colonised with pneumococcus. Younger age was significantly associated with pneumococcal colonisation. Among those colonised with pneumococcus, 35% were fully immunised, 30% were partially immunised, 30% had an unknown immunisation status and 4% were unimmunised. Eight (17%) of the children who were colonised with pneumococcus had pneumococcal-related conditions. The commonest serotype identified was 6A/B. Overall, 2% of the cohort were colonised with vaccine-serotype pneumococcus. Conclusion As a minority of children had evidence of nasopharyngeal colonisation with vaccine-serotype pneumococci, serotype replacement may be emerging in our population.
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Affiliation(s)
- Charity Newton
- Department of Paediatrics and Child Health, Faculty of Health Sciences, Sefako Makgatho Health Sciences University, Pretoria, South Africa
| | - Harry Maake
- Department of Paediatrics and Child Health, Faculty of Health Sciences, Sefako Makgatho Health Sciences University, Pretoria, South Africa
| | - Caroline Maluleka
- Department of Microbiology, Faculty of Health Sciences, Sefako Makgatho Health Sciences University, Pretoria, South Africa
| | - Siyazi Mda
- Faculty of Health Sciences, Nelson Mandela University, Port Elizabeth, South Africa
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10
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Hasegawa J, Mori M, Ohnishi H, Tsugawa T, Hori T, Yoto Y, Tsutsumi H. Pneumococcal vaccination reduces the risk of community-acquired pneumonia in children. Pediatr Int 2017; 59:316-320. [PMID: 27588365 DOI: 10.1111/ped.13157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 05/27/2016] [Accepted: 08/26/2016] [Indexed: 11/29/2022]
Abstract
BACKGROUND The seven-valent pneumococcal conjugate vaccine (PCV7) was introduced to Japan in 2009, after which there was a rapid decline in invasive pneumococcal disease. There are few data, however, on the effectiveness of PCV7 against community-acquired pneumonia (CAP). We conducted an ambispective cohort study among children aged 0-6 years old who attended day-care centers. METHODS A total of 624 children at 10 day-care centers in Sapporo, Japan participated in the study. The parents reported whether their child had received PCV7 one or more times, as well as the exact dates of vaccination from records in maternal and child health handbooks marked by pediatricians. Each CAP event was reported by parents according to doctor diagnosis. A Cox proportional hazards regression model was used to calculate the hazard ratio (HR) and 95%CI of CAP incidence reduced by PCV7 inoculation. RESULTS During the observational period, 94 subjects contracted CAP. After adjusting for potentially confounding variables, inoculation with PCV7 was significantly associated with a reduced risk of CAP (HR, 0.22; 95%CI: 0.13-0.34). On stratified analysis by age, PCV7 was significantly associated with a reduced risk of CAP in both children aged <3 years (HR, 0.31; 95%CI: 0.14-0.71), and those ≥3 years (HR, 0.20; 95%CI: 0.09-0.43). CONCLUSION PCV7 is highly effective in reducing the risk of CAP in children attending day-care centers.
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Affiliation(s)
- Junko Hasegawa
- Department of Public Health, Sapporo Medical University School of Medicine, Sapporo, Japan.,Department of Pediatrics, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Mitsuru Mori
- Department of Public Health, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Hirofumi Ohnishi
- Department of Public Health, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Takeshi Tsugawa
- Department of Pediatrics, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Tsukasa Hori
- Department of Pediatrics, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Yuko Yoto
- Department of Pediatrics, Sapporo Medical University School of Medicine, Sapporo, Japan
| | - Hiroyuki Tsutsumi
- Department of Pediatrics, Sapporo Medical University School of Medicine, Sapporo, Japan
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11
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Cui YA, Patel H, O'Neil WM, Li S, Saddier P. Pneumococcal serotype distribution: A snapshot of recent data in pediatric and adult populations around the world. Hum Vaccin Immunother 2017; 13:1-13. [PMID: 28125317 DOI: 10.1080/21645515.2016.1277300] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
S. pneumoniae infection remains a serious public health concern despite the availability of vaccines covering up to 23 of more than 94 known serotypes. The purpose of the present study was to monitor recent serotype distribution data. PubMed, EMBASE, Cochrane Reviews and Ingenta databases were searched. Serotype data covering invasive pneumococcal disease (IPD) and non-IPD were extracted from articles published from March 2014 to March 2015. Fifty-nine studies presented pneumococcal serotype prevalence by specific age categories. Most prevalent serotypes not covered by pneumococcal conjugate vaccines (PCV) were as follows: 15B, 22F, 15A, 23A among children under the age of 7 y with IPD; among adults with IPD: 22F, 11A, 10A, 38 in the 65 y and older age group; 12F, 9N, 8 in the 50-64 year-old age group and 12F, 8, 6C, 16F in the 15-59 age group. Geographic variations in serotype distribution highlight the importance of monitoring evolving pneumococcal serotype prevalence after pneumococcal vaccine implementation.
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Affiliation(s)
| | | | | | - Se Li
- a Merck & Co Inc. , Kenilworth , NJ , USA
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12
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Dube FS, van Mens SP, Robberts L, Wolter N, Nicol P, Mafofo J, Africa S, Zar HJ, Nicol MP. Comparison of a Real-Time Multiplex PCR and Sequetyping Assay for Pneumococcal Serotyping. PLoS One 2015; 10:e0137349. [PMID: 26335454 PMCID: PMC4559314 DOI: 10.1371/journal.pone.0137349] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2015] [Accepted: 08/14/2015] [Indexed: 02/06/2023] Open
Abstract
BACKGROUND Pneumococcal serotype identification is essential to monitor pneumococcal vaccine effectiveness and serotype replacement. Serotyping by conventional serological methods are costly, labour-intensive, and require significant technical expertise. We compared two different molecular methods to serotype pneumococci isolated from the nasopharynx of South African infants participating in a birth cohort study, the Drakenstein Child Health Study, in an area with high 13-valent pneumococcal conjugate vaccine (PCV13) coverage. METHODS A real-time multiplex PCR (rmPCR) assay detecting 21 different serotypes/-groups and a sequetyping assay, based on the sequence of the wzh gene within the pneumococcal capsular locus, were compared. Forty pneumococcal control isolates, with serotypes determined by the Quellung reaction, were tested. In addition, 135 pneumococcal isolates obtained from the nasopharynx of healthy children were tested by both serotyping assays and confirmed by Quellung testing. Discordant results were further investigated by whole genome sequencing of four isolates. RESULTS Of the 40 control isolates tested, 25 had a serotype covered by the rmPCR assay. These were all correctly serotyped/-grouped. Sequetyping PCR failed in 7/40 (18%) isolates. For the remaining isolates, sequetyping assigned the correct serotype/-group to 29/33 (88%) control isolates. Of the 132/135 (98%) nasopharyngeal pneumococcal isolates that could be typed, 69/132 (52%) and 112/132 (85%) were assigned the correct serotype/-group by rmPCR and sequetyping respectively. The serotypes of 63/132 (48%) isolates were not included in the rmPCR panel. All except three isolates (serotype 25A and 38) were theoretically amplified and differentiated into the correct serotype/-group with some strains giving ambigous results (serotype 13/20, 17F/33C, and 11A/D/1818F). Of the pneumococcal serotypes detected in this study, 69/91 (76%) were not included in the current PCV13. The most frequently identified serotypes were 11A, 13, 15B/15C, 16F and 10A. CONCLUSION The rmPCR assay performed well for the 21 serotypes/-groups included in the assay. However, in our study setting, a large proportion of serotypes were not detected by rmPCR. The sequetyping assay performed well, but did misassign specific serotypes. It may be useful for regions where vaccine serotypes are less common, however confirmatory testing is advisable.
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Affiliation(s)
- Felix S. Dube
- Division of Medical Microbiology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Suzan P. van Mens
- Division of Medical Microbiology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- Department of Medical Microbiology and Immunology, St Antonius Hospital, Nieuwegein, the Netherlands
| | - Lourens Robberts
- Division of Medical Microbiology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Nicole Wolter
- Centre for Respiratory Diseases and Meningitis (CRDM), National Institute for Communicable Diseases of the National Health Laboratory Service, Johannesburg, South Africa
- School of Pathology, Faculty of Health Sciences, University of the Witswatersrand, Johannesburg, South Africa
| | - Paul Nicol
- The State Agricultural Biotechnology Centre, Murdoch University, Murdoch, Australia
| | - Joseph Mafofo
- Centre for Proteomic and Genomic Research (CPGR), Cape Town, South Africa
| | - Samantha Africa
- Division of Medical Microbiology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
| | - Heather J. Zar
- Department of Paediatrics and Child Health, Red Cross War Memorial Children’s Hospital, Cape Town, South Africa
- MRC Unit on Child and Adolesscent Health, University of Cape Town, Cape Town, South Africa
| | - Mark P. Nicol
- Division of Medical Microbiology, Faculty of Health Sciences, University of Cape Town, Cape Town, South Africa
- National Health Laboratory Service, Groote Schuur Hospital, Cape Town, South Africa
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13
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Domenech M, Damián D, Ardanuy C, Liñares J, Fenoll A, García E. Emerging, Non-PCV13 Serotypes 11A and 35B of Streptococcus pneumoniae Show High Potential for Biofilm Formation In Vitro. PLoS One 2015; 10:e0125636. [PMID: 25927917 PMCID: PMC4415931 DOI: 10.1371/journal.pone.0125636] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 03/20/2015] [Indexed: 01/20/2023] Open
Abstract
Background Since the use of pneumococcal conjugate vaccines PCV7 and PCV13 in children became widespread, invasive pneumococcal disease (IPD) has dramatically decreased. Nevertheless, there has been a rise in incidence of Streptococcus pneumoniae non-vaccine serotypes (NVT) colonising the human nasopharynx. Nasopharyngeal colonisation, an essential step in the development of S. pneumoniae-induced IPD, is associated with biofilm formation. Although the capsule is the main pneumococcal virulence factor, the formation of pneumococcal biofilms might, in fact, be limited by the presence of capsular polysaccharide (CPS). Methodology/Principal Findings We used clinical isolates of 16 emerging, non-PCV13 serotypes as well as isogenic transformants of the same serotypes. The biofilm formation capacity of isogenic transformants expressing CPSs from NVT was evaluated in vitro to ascertain whether this trait can be used to predict the emergence of NVT. Fourteen out of 16 NVT analysed were not good biofilm formers, presumably because of the presence of CPS. In contrast, serotypes 11A and 35B formed ≥45% of the biofilm produced by the non-encapsulated M11 strain. Conclusions/Significance This study suggest that emerging, NVT serotypes 11A and 35B deserve a close surveillance.
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Affiliation(s)
- Mirian Domenech
- Centro de Investigaciones Biológicas, CSIC, Madrid, Spain; CIBER de Enfermedades Respiratorias (CIBERES), Madrid, Spain
| | - Diana Damián
- Centro de Investigaciones Biológicas, CSIC, Madrid, Spain
| | - Carmen Ardanuy
- CIBER de Enfermedades Respiratorias (CIBERES), Madrid, Spain; Hospital Universitari de Bellvitge-Universitat de Barcelona-Fundació Privada Institut d'Investigació Biomèdica de Bellvitge, Barcelona, Spain
| | - Josefina Liñares
- CIBER de Enfermedades Respiratorias (CIBERES), Madrid, Spain; Hospital Universitari de Bellvitge-Universitat de Barcelona-Fundació Privada Institut d'Investigació Biomèdica de Bellvitge, Barcelona, Spain
| | - Asunción Fenoll
- Centro Nacional de Microbiología, Instituto de Salud Carlos III, Madrid, Spain
| | - Ernesto García
- Centro de Investigaciones Biológicas, CSIC, Madrid, Spain; CIBER de Enfermedades Respiratorias (CIBERES), Madrid, Spain
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