1
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Ben-Shimol S, Dagan R, Givon-Lavi N, Avital D, Bar-Ziv J, Greenberg D. Use of Chest Radiography Examination as a Probe for Pneumococcal Conjugate Vaccine Impact on Lower Respiratory Tract Infections in Young Children. Clin Infect Dis 2021; 71:177-187. [PMID: 31414125 DOI: 10.1093/cid/ciz768] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 08/08/2019] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Community-acquired alveolar pneumonia (CAAP) is considered a bacterial disease, mainly pneumococcal. CAAP rates markedly declined following 7- and 13-valent pneumococcal conjugate vaccine (PCV) introductions worldwide. In contrast, non-CAAP lower respiratory tract infections (NA-LRIs) are generally not considered pneumococcal diseases. We assessed CAAP, NA-LRIs, and overall visits with chest radiograph (CXR) examination rates in the pediatric emergency room in southern Israel before and after PCV implementation. METHODS This was an ongoing, prospective observational study. Our hospital serves a captive population of approximately 75 000 children aged <5 years, enabling incidence calculation. PCV7 and PCV13 were implemented in Israel in July 2009 and November 2010, respectively. All CXRs were analyzed according to the World Health Organization Standardization of Interpretation. We calculated CAAP, NA-LRI, and CXR examinations annual incidences from 2004 to 2017 and incidence rate ratios comparing the PCV13 (2014-2017) with the pre-PCV (2004-2008) periods. RESULTS Overall, 72 746 CXR examinations were recorded: 14% CAAP and 86% NA-LRI. CAAP, NA-LRI, and CXR examination visit rates declined by 49%, 34%, and 37%, respectively. This pattern was seen in Jewish and Bedouin children (the 2 ethnically distinct populations), with steeper declines observed among Jewish children and children aged >12 months. CONCLUSIONS PCV7/PCV13 implementation resulted in a marked decline in CAAP and overall visits with CXR examination rates in young children. Overall, approximately 14 750 hospital visits with CXR were prevented annually per 100 000 population aged <5 years. These findings suggest that although NA-LRIs are usually not considered pneumococcal, many can be prevented by PCVs.Pneumococcal conjugate vaccine (PCV7/PCV13) implementation resulted in significant declines in community-acquired alveolar pneumonia (CAAP) and overall chest radiography examination rates in young children. Although non-CAAP lower respiratory tract infections are usually not considered pneumococcal, many can be prevented by PCVs.
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Affiliation(s)
- Shalom Ben-Shimol
- Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer-Sheva, Israel
| | - Ron Dagan
- Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer-Sheva, Israel
| | - Noga Givon-Lavi
- Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer-Sheva, Israel
| | - Dekel Avital
- Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer-Sheva, Israel
| | - Jacob Bar-Ziv
- Department of Radiology, Hadassah Medical Center, Jerusalem, Israel
| | - David Greenberg
- Faculty of Health Sciences, Ben-Gurion University of the Negev, Beer-Sheva, Israel.,Pediatric Infectious Disease Unit, Soroka University Medical Center, Beer-Sheva, Israel
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2
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Monto AS, Fukuda K. Lessons From Influenza Pandemics of the Last 100 Years. Clin Infect Dis 2021; 70:951-957. [PMID: 31420670 PMCID: PMC7314237 DOI: 10.1093/cid/ciz803] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 08/14/2019] [Indexed: 01/15/2023] Open
Abstract
Seasonal influenza is an annual occurrence, but it is the threat of pandemics that produces universal concern. Recurring reports of avian influenza viruses severely affecting humans have served as constant reminders of the potential for another pandemic. Review of features of the 1918 influenza pandemic and subsequent ones helps in identifying areas where attention in planning is critical. Key among such issues are likely risk groups and which interventions to employ. Past pandemics have repeatedly underscored, for example, the vulnerability of groups such as pregnant women and taught other lessons valuable for future preparedness. While a fundamental difficulty in planning for the next pandemic remains their unpredictability and infrequency, this uncertainty can be mitigated, in part, by optimizing the handling of the much more predictable occurrence of seasonal influenza. Improvements in antivirals and novel vaccine formulations are critical in lessening the impact of both pandemic and seasonal influenza.
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Affiliation(s)
- Arnold S Monto
- Department of Epidemiology, University of Michigan School of Public Health, Ann Arbor
| | - Keiji Fukuda
- School of Public Health, Li Ka Shing Faculty of Medicine, University of Hong Kong, Pokfulam
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3
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Islam MT, Im J, Ahmmed F, Kim DR, Khan AI, Zaman K, Ali M, Marks F, Qadri F, Kim JH, Clemens JD. Use of Typhoid Vi-Polysaccharide Vaccine as a Vaccine Probe to Delineate Clinical Criteria for Typhoid Fever. Am J Trop Med Hyg 2020; 103:665-671. [PMID: 32588803 PMCID: PMC7410438 DOI: 10.4269/ajtmh.19-0968] [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] [Indexed: 11/23/2022] Open
Abstract
Blood cultures (BCs) detect an estimated 50% of typhoid fever cases. There is need for validated clinical criteria to define cases that are BC negative, both to help direct empiric antibiotic treatment and to better evaluate the magnitude of protection conferred by typhoid vaccines. To derive and validate a clinical rule for defining BC-negative typhoid fever, we assessed, in a cluster-randomized effectiveness trial of Vi-polysaccharide (ViPS) typhoid vaccine in Kolkata, India, 14,797 episodes of fever lasting at least 3 days during 4 years of comprehensive, BC-based surveillance of 70,865 persons. A recursive partitioning algorithm was used to develop a decision rule to predict BC-proven typhoid cases with a diagnostic specificity of 97–98%. To validate this rule as a definition for BC-negative typhoid fever, we assessed whether the rule defined culture-negative syndromes prevented by ViPS vaccine. In a training subset of individuals, we identified the following two rules: rule 1: patients aged < 15 years with prolonged fever accompanied by a measured body temperature ≥ 100°F, headache, and nausea; rule 2: patients aged ≥ 15 years with prolonged fever accompanied by nausea and palpable liver but without constipation. The adjusted protective efficacy of ViPS against clinical typhoid defined by these rules in persons aged ≥ 2 years in a separate validation subset was 33% (95% CI: 4–53%). We have defined and validated a clinical rule for predicting BC-negative typhoid fever using a novel vaccine probe approach. If validated in other settings, this rule may be useful to guide clinical care and to enhance typhoid vaccine evaluations.
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Affiliation(s)
- Md Taufiqul Islam
- International Centre for Diarrheal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Justin Im
- International Vaccine Institute, Seoul, Republic of Korea
| | - Faisal Ahmmed
- International Centre for Diarrheal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Deok Ryun Kim
- International Vaccine Institute, Seoul, Republic of Korea
| | - Ashraful Islam Khan
- International Centre for Diarrheal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Khalequ Zaman
- International Centre for Diarrheal Disease Research, Bangladesh, Dhaka, Bangladesh
| | | | - Florian Marks
- Department of Medicine, University of Cambridge, Cambridge, United Kingdom.,International Vaccine Institute, Seoul, Republic of Korea
| | - Firdausi Qadri
- International Centre for Diarrheal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Jerome H Kim
- International Vaccine Institute, Seoul, Republic of Korea
| | - John D Clemens
- Korea University College of Medicine, Seoul, South Korea.,UCLA Fielding School of Public Health, Los Angeles, California.,International Centre for Diarrheal Disease Research, Bangladesh, Dhaka, Bangladesh
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4
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Ortiz JR, Neuzil KM. Influenza Immunization in Low- and Middle-Income Countries: Preparing for Next-Generation Influenza Vaccines. J Infect Dis 2019; 219:S97-S106. [DOI: 10.1093/infdis/jiz024] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Justin R Ortiz
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore
| | - Kathleen M Neuzil
- Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore
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5
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Bresee J, Fitzner J, Campbell H, Cohen C, Cozza V, Jara J, Krishnan A, Lee V. Progress and Remaining Gaps in Estimating the Global Disease Burden of Influenza. Emerg Infect Dis 2019; 24:1173-1177. [PMID: 29912681 PMCID: PMC6038739 DOI: 10.3201/eid2407.171270] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Influenza has long been a global public health priority because of the threat of another global pandemic. Although data are available for the annual burden of seasonal influenza in many developed countries, fewer disease burden data are available for low-income and tropical countries. In recent years, however, the surveillance systems created as part of national pandemic preparedness efforts have produced substantial data on the epidemiology and impact of influenza in countries where data were sparse. These data are leading to greater interest in seasonal influenza, including implementation of vaccination programs. However, a lack of quality data on severe influenza, nonrespiratory outcomes, and high-risk groups, as well as a need for better mathematical models and economic evaluations, are some of the major gaps that remain. These gaps are the focus of multilateral research and surveillance efforts that will strengthen global efforts in influenza control in the future.
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6
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Monto AS. Reflections on The Global Influenza Surveillance and Response System (GISRS) at 65 Years: An Expanding Framework for Influenza Detection, Prevention and Control. Influenza Other Respir Viruses 2019; 12:10-12. [PMID: 29460424 PMCID: PMC5818347 DOI: 10.1111/irv.12511] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/12/2017] [Indexed: 12/02/2022] Open
Affiliation(s)
- Arnold S Monto
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI, USA
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7
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Mortality, morbidity, and hospitalisations due to influenza lower respiratory tract infections, 2017: an analysis for the Global Burden of Disease Study 2017. THE LANCET. RESPIRATORY MEDICINE 2019; 7:69-89. [PMID: 30553848 PMCID: PMC6302221 DOI: 10.1016/s2213-2600(18)30496-x] [Citation(s) in RCA: 293] [Impact Index Per Article: 58.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 11/07/2018] [Accepted: 11/08/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND Although the burden of influenza is often discussed in the context of historical pandemics and the threat of future pandemics, every year a substantial burden of lower respiratory tract infections (LRTIs) and other respiratory conditions (like chronic obstructive pulmonary disease) are attributable to seasonal influenza. The Global Burden of Disease Study (GBD) 2017 is a systematic scientific effort to quantify the health loss associated with a comprehensive set of diseases and disabilities. In this Article, we focus on LRTIs that can be attributed to influenza. METHODS We modelled the LRTI incidence, hospitalisations, and mortality attributable to influenza for every country and selected subnational locations by age and year from 1990 to 2017 as part of GBD 2017. We used a counterfactual approach that first estimated the LRTI incidence, hospitalisations, and mortality and then attributed a fraction of those outcomes to influenza. FINDINGS Influenza LRTI was responsible for an estimated 145 000 (95% uncertainty interval [UI] 99 000-200 000) deaths among all ages in 2017. The influenza LRTI mortality rate was highest among adults older than 70 years (16·4 deaths per 100 000 [95% UI 11·6-21·9]), and the highest rate among all ages was in eastern Europe (5·2 per 100 000 population [95% UI 3·5-7·2]). We estimated that influenza LRTIs accounted for 9 459 000 (95% UI 3 709 000-22 935 000) hospitalisations due to LRTIs and 81 536 000 hospital days (24 330 000-259 851 000). We estimated that 11·5% (95% UI 10·0-12·9) of LRTI episodes were attributable to influenza, corresponding to 54 481 000 (38 465 000-73 864 000) episodes and 8 172 000 severe episodes (5 000 000-13 296 000). INTERPRETATION This comprehensive assessment of the burden of influenza LRTIs shows the substantial annual effect of influenza on global health. Although preparedness planning will be important for potential pandemics, health loss due to seasonal influenza LRTIs should not be overlooked, and vaccine use should be considered. Efforts to improve influenza prevention measures are needed. FUNDING Bill & Melinda Gates Foundation.
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8
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Madhi SA, Nunes MC. Experience and challenges on influenza and pertussis vaccination in pregnant women. Hum Vaccin Immunother 2018; 14:2183-2188. [PMID: 30024822 PMCID: PMC6183140 DOI: 10.1080/21645515.2018.1483810] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Young infants contribute to relatively high burden of vaccine-preventable diseases, including infections by influenza virus and Bordetella pertussis. Vaccination of pregnant women can enhance transplacental transfer of protective antibody to the fetus and protect the infant against disease during the first few months of life. Pregnant women are a priority group for seasonal influenza vaccination, due to third-trimester pregnancy being a risk-factor for severe influenza illness. Furthermore, randomized controlled trials confirmed that influenza vaccination during pregnancy confers protection against influenza-confirmed illness in the women, and their infants up to 3 months of age; and is also associated with 20% reduction in all-cause pneumonia among young-infants. Maternal influenza vaccination might also reduce the risk of low-birth weight, preterm births, and stillbirths however, data on this is conflicting. Vaccination of pregnant women with acellular pertussis vaccines reduces pertussis in their young infants by up to 93%. The increase in specific pertussis antibody among the infants born to vaccinated women might, however, interfere with the active pertussis vaccination of the infant following the primary series of vaccines. The clinical implication of this is yet to be ascertained, particularly since immune responses following the booster vaccine are unaffected. Vaccination of pregnant women with inactivated influenza vaccine and acellular pertussis vaccine have been demonstrated to confer protection to their young infants, and warrants consideration for inclusion into public health immunization programs, including in low and middle income countries.
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Affiliation(s)
- Shabir A Madhi
- a Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, Faculty Health Sciences , University of the Witwatersrand , Johannesburg , South Africa.,b Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty Health Sciences , University of the Witwatersrand , Johannesburg , South Africa
| | - Marta C Nunes
- a Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, Faculty Health Sciences , University of the Witwatersrand , Johannesburg , South Africa.,b Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty Health Sciences , University of the Witwatersrand , Johannesburg , South Africa
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9
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Commentary: Quantifying the Impact of Maternal Influenza Vaccination-Beyond Laboratory-Confirmed Efficacy. Pediatr Infect Dis J 2018; 37:441-442. [PMID: 29485522 DOI: 10.1097/inf.0000000000001967] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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10
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Nunes MC, Madhi SA. Prevention of influenza-related illness in young infants by maternal vaccination during pregnancy. F1000Res 2018; 7:122. [PMID: 29445450 PMCID: PMC5791002 DOI: 10.12688/f1000research.12473.1] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/23/2018] [Indexed: 12/15/2022] Open
Abstract
The influenza virus circulates yearly and causes global epidemics. Influenza infection affects all age groups and causes mild to severe illness, and young infants are at particular risk for serious disease. The most effective measure to prevent influenza disease is vaccination; however, no vaccine is licensed for use in infants younger than 6 months old. Thus, there is a crucial need for other preventive strategies in this high-risk age group. Influenza vaccination during pregnancy protects both the mothers and the young infants against influenza infection. Vaccination during pregnancy boosts the maternal antibodies and increases the transfer of immunoglobulin G from the mother to the fetus through the placenta, which confers protection against infection in infants too young to be vaccinated. Data from clinical trials and observational studies did not demonstrate adverse effects to the mother, the fetus, or the infant after maternal influenza vaccination. We present the current data on the effectiveness and safety of influenza vaccination during pregnancy in preventing disease in the young infant.
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Affiliation(s)
- Marta C Nunes
- Medical Research Council, Respiratory and Meningeal Pathogens Research Unit, University of the Witwatersrand, Johannesburg, South Africa.,Department of Science and Technology/National Research Foundation, Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa
| | - Shabir A Madhi
- Medical Research Council, Respiratory and Meningeal Pathogens Research Unit, University of the Witwatersrand, Johannesburg, South Africa.,Department of Science and Technology/National Research Foundation, Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa
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11
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Influenza immunization of pregnant women in resource-constrained countries: an update for funding and implementation decisions. Curr Opin Infect Dis 2018; 30:455-462. [PMID: 28777109 DOI: 10.1097/qco.0000000000000392] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
PURPOSE OF REVIEW In 2018, Gavi, the Vaccine Alliance, is expected to review the strategy of maternal influenza immunization for potential investment in low-income countries. RECENT FINDINGS Clinical trial data confirm the efficacy of maternal influenza immunization to prevent influenza disease in both mothers and their infants during the first months of life. Trial and observational data indicate no significant adverse events in mothers or newborns. High-quality disease burden data, particularly for seasonal influenza in low-income and middle-income countries, are limited. Thus, the anticipated impact of maternal influenza immunization programs on severe illness is unclear. However, assessments of the public health value of investment in maternal influenza immunization should extend beyond calculations of disease prevention and include broader effects such as improving health systems for antenatal care delivery, preventing inappropriate antibacterial prescribing, building a platform for other vaccines to be used during pregnancy, and strengthening systems to regulate, procure, and distribute influenza vaccines in response to a future pandemic. SUMMARY A global investment in a maternal influenza immunization strategy would prevent influenza disease in pregnant women and their infants. It would also provide additional public health value by strengthening antenatal care systems and improving country pandemic preparedness.
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12
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Ortiz JR, Hickling J, Jones R, Donabedian A, Engelhardt OG, Katz JM, Madhi SA, Neuzil KM, Rimmelzwaan GF, Southern J, Spiro DJ, Hombach J. Report on eighth WHO meeting on development of influenza vaccines that induce broadly protective and long-lasting immune responses: Chicago, USA, 23-24 August 2016. Vaccine 2017; 36:932-938. [PMID: 29221895 DOI: 10.1016/j.vaccine.2017.11.061] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 11/17/2017] [Indexed: 12/26/2022]
Abstract
In August 2016, the World Health Organization (WHO) convened the "Eighth meeting on development of influenza vaccines that induce broadly protective and long-lasting immune responses" to discuss the regulatory requirements and pathways for licensure of next-generation influenza vaccines, and to identify areas where WHO can promote the development of such vaccines. Participants included approximately 120 representatives of academia, the vaccine industry, research and development funders, and regulatory and public health agencies. They reviewed the draft WHO preferred product characteristics (PPCs) of vaccines that could address prioritized unmet public health needs and discussed the challenges facing the development of such vaccines, especially for low- and middle-income countries (LMIC). They defined the data desired by public-health decision makers globally and explored how to support the progression of promising candidates into late-stage clinical trials and for all countries. This report highlights the major discussions of the meeting.
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Affiliation(s)
- Justin R Ortiz
- Initiative for Vaccine Research, World Health Organization (WHO), Geneva, Switzerland.
| | - Julian Hickling
- Working in Tandem Ltd, Cambridge, Northern Ireland, United Kingdom.
| | - Rebecca Jones
- Working in Tandem Ltd, Cambridge, Northern Ireland, United Kingdom.
| | - Armen Donabedian
- Biomedical Advanced Research and Development Authority, United States Department of Health and Human Services, Washington DC, United States.
| | - Othmar G Engelhardt
- Division of Virology, National Institute for Biological Standards and Control, A Centre of the Medicines and Healthcare products Regulatory Agency, Potters Bar, Hertfordshire, United Kingdom.
| | - Jacqueline M Katz
- Influenza Division, Centers for Disease Control and Prevention (CDC), Atlanta, United States.
| | - Shabir A Madhi
- Medical Research Council: Respiratory and Meningeal Pathogens Research Unit, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
| | - Kathleen M Neuzil
- Center for Vaccine Development, University of Maryland School of Medicine, Baltimore, United States.
| | - Guus F Rimmelzwaan
- Erasmus Medical Center, Department of Viroscience, Rotterdam, The Netherlands.
| | - James Southern
- Advisor to Medicines Control Council, Simon's Town, South Africa.
| | - David J Spiro
- National Institutes of Health, Bethesda, United States.
| | - Joachim Hombach
- Initiative for Vaccine Research, World Health Organization (WHO), Geneva, Switzerland.
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13
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Malosh RE, Martin ET, Ortiz JR, Monto AS. The risk of lower respiratory tract infection following influenza virus infection: A systematic and narrative review. Vaccine 2017; 36:141-147. [PMID: 29157959 PMCID: PMC5736984 DOI: 10.1016/j.vaccine.2017.11.018] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 11/07/2017] [Indexed: 01/18/2023]
Abstract
Background Lower respiratory tract infections (LRTI) are a major cause of morbidity and mortality worldwide, particularly in young children and older adults. Influenza is known to cause severe disease but the risk of developing LRTI following influenza virus infection in various populations has not been systematically reviewed. Such data are important for estimating the impact specific influenza vaccine programs would have on LRTI outcomes in a community. We sought to review the published literature to determine the risk of developing LRTI following an influenza virus infection in individuals of any age. Methods and findings We conducted a systematic review to identify prospective studies that estimated the incidence of LRTI following laboratory-confirmed influenza virus infection. We searched PubMed, Medline, and Embase databases for relevant literature. We supplemented this search with a narrative review of influenza and LRTI. The systematic review identified two prospective studies that both followed children less than 5 years. We also identified one additional pediatric study from our narrative review meeting the study inclusion criteria. Finally, we summarized recent case-control studies on the etiology of pneumonia in both adults and children. Conclusions There is a dearth of prospective studies evaluating the risk of developing LRTI following influenza virus infection. Determining the burden of severe LRTI that is attributable to influenza is necessary to estimate the benefits of influenza vaccine on this important public health outcome. Vaccine probe studies are an efficient way to evaluate these questions and should be encouraged going forward.
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Affiliation(s)
- Ryan E Malosh
- University of Michigan School of Public Health, Ann Arbor, MI, United States
| | - Emily T Martin
- University of Michigan School of Public Health, Ann Arbor, MI, United States
| | | | - Arnold S Monto
- University of Michigan School of Public Health, Ann Arbor, MI, United States.
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14
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Neuzil KM, Bresee JS, de la Hoz F, Johansen K, Karron RA, Krishnan A, Madhi SA, Mangtani P, Spiro DJ, Ortiz JR. Data and product needs for influenza immunization programs in low- and middle-income countries: Rationale and main conclusions of the WHO preferred product characteristics for next-generation influenza vaccines. Vaccine 2017; 35:5734-5737. [DOI: 10.1016/j.vaccine.2017.08.088] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Accepted: 08/22/2017] [Indexed: 11/26/2022]
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15
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Influenza epidemiology and immunization during pregnancy: Final report of a World Health Organization working group. Vaccine 2017; 35:5738-5750. [PMID: 28867508 PMCID: PMC8274347 DOI: 10.1016/j.vaccine.2017.08.037] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 08/17/2017] [Indexed: 12/05/2022]
Abstract
From 2014 to 2017, the World Health Organization convened a working group to evaluate influenza disease burden and vaccine efficacy to inform estimates of maternal influenza immunization program impact. The group evaluated existing systematic reviews and relevant primary studies, and conducted four new systematic reviews. There was strong evidence that maternal influenza immunization prevented influenza illness in pregnant women and their infants, although data on severe illness prevention were lacking. The limited number of studies reporting influenza incidence in pregnant women and infants under six months had highly variable estimates and underrepresented low- and middle-income countries. The evidence that maternal influenza immunization reduces the risk of adverse birth outcomes was conflicting, and many observational studies were subject to substantial bias. The lack of scientific clarity regarding disease burden or magnitude of vaccine efficacy against severe illness poses challenges for robust estimation of the potential impact of maternal influenza immunization programs.
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16
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Abstract
Influenza is a common respiratory illness in children and accounts for substantial morbidity and mortality on an annual basis. Inactivated and live influenza vaccines are approved for children and are safe and efficacious. The absolute effectiveness of vaccines varies by year and is influenced by several factors. The reason for recent reduced performance of live-attenuated influenza vaccines is poorly understood, and active research is ongoing. Vaccination programs are less common in tropical and subtropical countries, where unique logistical and feasibility challenges exist. Antiviral medications for prevention and treatment of influenza in children are an important adjunct to vaccines.
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Affiliation(s)
- Elizabeth T Rotrosen
- Center for Vaccine Development, University of Maryland, School of Medicine, 685 West Baltimore Street, Room 480, Baltimore, MD 21201, USA
| | - Kathleen M Neuzil
- Center for Vaccine Development, University of Maryland, School of Medicine, 685 West Baltimore Street, Room 480, Baltimore, MD 21201, USA.
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17
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Fell DB, Savitz DA, Kramer MS, Gessner BD, Katz MA, Knight M, Luteijn JM, Marshall H, Bhat N, Gravett MG, Skidmore B, Ortiz JR. Maternal influenza and birth outcomes: systematic review of comparative studies. BJOG 2017; 124:48-59. [PMID: 27264387 PMCID: PMC5216449 DOI: 10.1111/1471-0528.14143] [Citation(s) in RCA: 104] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/15/2016] [Indexed: 01/12/2023]
Abstract
BACKGROUND Although pregnant women are considered at high risk for severe influenza disease, comparative studies of maternal influenza and birth outcomes have not been comprehensively summarised. OBJECTIVE To review comparative studies evaluating maternal influenza disease and birth outcomes. SEARCH STRATEGY We searched bibliographic databases from inception to December 2014. SELECTION CRITERIA Studies of preterm birth, small-for-gestational-age (SGA) birth or fetal death, comparing women with and without clinical influenza illness or laboratory-confirmed influenza infection during pregnancy. DATA COLLECTION AND ANALYSIS Two reviewers independently abstracted data and assessed study quality. MAIN RESULTS Heterogeneity across 16 studies reporting preterm birth precluded meta-analysis. In a subgroup of the highest-quality studies, two reported significantly increased preterm birth (risk ratios (RR) from 2.4 to 4.0) following severe 2009 pandemic H1N1 (pH1N1) influenza illness, whereas those assessing mild-to-moderate pH1N1 or seasonal influenza found no association. Five studies of SGA birth showed no discernible patterns with respect to influenza disease severity (pooled odds ratio 1.24; 95% CI 0.96-1.59). Two fetal death studies were of sufficient quality and size to permit meaningful interpretation. Both reported an increased risk of fetal death following maternal pH1N1 disease (RR 1.9 for mild-to-moderate disease and 4.2 for severe disease). CONCLUSIONS Comparative studies of preterm birth, SGA birth and fetal death following maternal influenza disease are limited in number and quality. An association between severe pH1N1 disease and preterm birth and fetal death was reported by several studies; however, these limited data do not permit firm conclusions on the magnitude of any association. TWEETABLE ABSTRACT Comparative studies are limited in quality but suggest severe pandemic H1N1 influenza increases preterm birth.
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Affiliation(s)
- DB Fell
- Department of Epidemiology, Biostatistics and Occupational HealthMcGill UniversityMontrealQCCanada
- Better Outcomes Registry & Network (BORN)CHEO Research InstituteOttawaONCanada
| | - DA Savitz
- Department of EpidemiologyBrown UniversityProvidenceRIUSA
- Department of Obstetrics and GynecologyBrown UniversityProvidenceRIUSA
| | - MS Kramer
- Department of Epidemiology, Biostatistics and Occupational HealthMcGill UniversityMontrealQCCanada
- Department of PediatricsMcGill University Faculty of MedicineMontrealQCCanada
| | - BD Gessner
- Agence de Médecine PréventiveParisFrance
| | - MA Katz
- Independent ConsultantTel AvivIsrael
| | - M Knight
- National Perinatal Epidemiology UnitUniversity of OxfordOxfordUK
| | | | - H Marshall
- Vaccinology and Immunology Research Trials UnitWomen's and Children's HospitalNorth AdelaideSAAustralia
- School of MedicineUniversity of AdelaideNorth AdelaideSAAustralia
- Robinson Research InstituteUniversity of AdelaideNorth AdelaideSAAustralia
| | | | - MG Gravett
- Department of Obstetrics and GynecologyUniversity of WashingtonSeattleWAUSA
- Global Alliance to Prevent Prematurity and StillbirthSeattle Children'sSeattleWAUSA
| | | | - JR Ortiz
- Initiative for Vaccine ResearchWorld Health OrganizationGenevaSwitzerland
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18
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Brooks WA, Zaman K, Lewis KDC, Ortiz JR, Goswami D, Feser J, Sharmeen AT, Nahar K, Rahman M, Rahman MZ, Barin B, Yunus M, Fry AM, Bresee J, Azim T, Neuzil KM. Efficacy of a Russian-backbone live attenuated influenza vaccine among young children in Bangladesh: a randomised, double-blind, placebo-controlled trial. LANCET GLOBAL HEALTH 2016; 4:e946-e954. [PMID: 27746226 PMCID: PMC5118223 DOI: 10.1016/s2214-109x(16)30200-5] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 07/18/2016] [Accepted: 07/29/2016] [Indexed: 11/06/2022]
Abstract
Background The rates of influenza illness and associated complications are high among children in Bangladesh. We assessed the clinical efficacy and safety of a Russian-backbone live attenuated influenza vaccine (LAIV) at two field sites in Bangladesh. Methods Between Feb 27 and April 9, 2013, children aged 2–4 years in urban Kamalapur and rural Matlab, Bangladesh, were randomly assigned in a 2:1 ratio, according to a computer-generated schedule, to receive one intranasal dose of LAIV or placebo. After vaccination, we monitored children in weekly home visits until Dec 31, 2013, with study clinic surveillance for influenza illness. The primary outcome was symptomatic, laboratory-confirmed influenza illness due to vaccine-matched strains. Analysis was per protocol. The trial is registered with ClinicalTrials.gov, number NCT01797029. Findings Of 1761 children enrolled, 1174 received LAIV and 587 received placebo. Laboratory-confirmed influenza illness due to vaccine-matched strains was seen in 93 (15·8%) children in the placebo group and 79 (6·7%) in the LAIV group. Vaccine efficacy of LAIV for vaccine-matched strains was 57·5% (95% CI 43·6–68·0). The vaccine was well tolerated, and adverse events were balanced between the groups. The most frequent adverse events were tachypnoea (n=86 in the LAIV group and n=54 in the placebo group), cough (n=73 and n=43), and runny nose (n=68 and n=39), most of which were mild. Interpretation This single-dose Russian-backbone LAIV was safe and efficacious at preventing symptomatic laboratory-confirmed influenza illness due to vaccine-matched strains. LAIV programmes might reduce the burden of influenza illness in Bangladesh. Funding The Bill & Melinda Gates Foundation.
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Affiliation(s)
- W Abdullah Brooks
- International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh; International Health, Johns Hopkins University, Baltimore, MD, USA
| | - K Zaman
- International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | | | - Justin R Ortiz
- PATH, Seattle, WA, USA; Departments of Global Health and Medicine, University of Washington, Seattle, WA, USA
| | - Doli Goswami
- International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | | | - Amina Tahia Sharmeen
- International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Kamrun Nahar
- International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Mustafizur Rahman
- International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | | | - Burc Barin
- The EMMES Corporation, Rockville, MD, USA
| | - Muhammad Yunus
- International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
| | - Alicia M Fry
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Joseph Bresee
- Influenza Division, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Tasnim Azim
- International Centre for Diarrhoeal Disease Research, Bangladesh, Dhaka, Bangladesh
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19
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Lafond KE, Nair H, Rasooly MH, Valente F, Booy R, Rahman M, Kitsutani P, Yu H, Guzman G, Coulibaly D, Armero J, Jima D, Howie SRC, Ampofo W, Mena R, Chadha M, Sampurno OD, Emukule GO, Nurmatov Z, Corwin A, Heraud JM, Noyola DE, Cojocaru R, Nymadawa P, Barakat A, Adedeji A, von Horoch M, Olveda R, Nyatanyi T, Venter M, Mmbaga V, Chittaganpitch M, Nguyen TH, Theo A, Whaley M, Azziz-Baumgartner E, Bresee J, Campbell H, Widdowson MA. Global Role and Burden of Influenza in Pediatric Respiratory Hospitalizations, 1982-2012: A Systematic Analysis. PLoS Med 2016; 13:e1001977. [PMID: 27011229 PMCID: PMC4807087 DOI: 10.1371/journal.pmed.1001977] [Citation(s) in RCA: 253] [Impact Index Per Article: 31.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 02/05/2016] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND The global burden of pediatric severe respiratory illness is substantial, and influenza viruses contribute to this burden. Systematic surveillance and testing for influenza among hospitalized children has expanded globally over the past decade. However, only a fraction of the data has been used to estimate influenza burden. In this analysis, we use surveillance data to provide an estimate of influenza-associated hospitalizations among children worldwide. METHODS AND FINDINGS We aggregated data from a systematic review (n = 108) and surveillance platforms (n = 37) to calculate a pooled estimate of the proportion of samples collected from children hospitalized with respiratory illnesses and positive for influenza by age group (<6 mo, <1 y, <2 y, <5 y, 5-17 y, and <18 y). We applied this proportion to global estimates of acute lower respiratory infection hospitalizations among children aged <1 y and <5 y, to obtain the number and per capita rate of influenza-associated hospitalizations by geographic region and socio-economic status. Influenza was associated with 10% (95% CI 8%-11%) of respiratory hospitalizations in children <18 y worldwide, ranging from 5% (95% CI 3%-7%) among children <6 mo to 16% (95% CI 14%-20%) among children 5-17 y. On average, we estimated that influenza results in approximately 374,000 (95% CI 264,000 to 539,000) hospitalizations in children <1 y-of which 228,000 (95% CI 150,000 to 344,000) occur in children <6 mo-and 870,000 (95% CI 610,000 to 1,237,000) hospitalizations in children <5 y annually. Influenza-associated hospitalization rates were more than three times higher in developing countries than in industrialized countries (150/100,000 children/year versus 48/100,000). However, differences in hospitalization practices between settings are an important limitation in interpreting these findings. CONCLUSIONS Influenza is an important contributor to respiratory hospitalizations among young children worldwide. Increasing influenza vaccination coverage among young children and pregnant women could reduce this burden and protect infants <6 mo.
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Affiliation(s)
- Kathryn E. Lafond
- Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
- School of Health Sciences, University of Tampere, Tampere, Finland
- * E-mail: (KEL); (MAW)
| | - Harish Nair
- Centre for Global Health Research, University of Edinburgh, Edinburgh, United Kingdom
- Public Health Foundation of India, New Delhi, India
| | - Mohammad Hafiz Rasooly
- Afghanistan National Public Health Institute, Ministry of Public Health, Kabul, Afghanistan
| | - Fátima Valente
- National Directorate of Public Health, Ministry of Health, Luanda, Angola
| | - Robert Booy
- National Centre for Immunisation Research and Surveillance, The Children’s Hospital at Westmead, Westmead, New South Wales, Australia
| | - Mahmudur Rahman
- Institute of Epidemiology, Disease Control and Research, Dhaka, Bangladesh
| | - Paul Kitsutani
- Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Hongjie Yu
- Division of Infectious Disease, Key Laboratory of Surveillance and Early-warning on Infectious Disease, Chinese Centre for Disease Control and Prevention, Beijing, China
| | | | | | - Julio Armero
- Ministerio de Salud de El Salvador, San Salvador, El Salvador
| | - Daddi Jima
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Stephen R. C. Howie
- Medical Research Council Unit, Fajara, The Gambia
- Department of Paediatrics, University of Auckland, Auckland, New Zealand
- Centre for International Health, University of Otago, Dunedin, New Zealand
| | - William Ampofo
- Noguchi Memorial Institute for Medical Research, University of Ghana, Accra, Ghana
| | - Ricardo Mena
- Ministerio de Salud Publica y Asistencia Social, Guatemala City, Guatemala
| | | | - Ondri Dwi Sampurno
- National Institute of Health Research and Development, Jakarta, Indonesia
| | | | | | - Andrew Corwin
- Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Jean Michel Heraud
- National Influenza Centre, Virology Unit, Institut Pasteur of Madagascar, Antananarivo, Madagascar
| | - Daniel E. Noyola
- Universidad Autónoma de San Luis Potosí, San Luis Potosí, Mexico
| | - Radu Cojocaru
- National Centre for Public Health, Chisinau, Republic of Moldova
| | | | - Amal Barakat
- Institut National d’Hygiène, Ministère de la Santé, Rabat, Morocco
| | | | - Marta von Horoch
- Ministerio de Salud Publica y Bienestar Social, Asunción, Paraguay
| | - Remigio Olveda
- Research Institute for Tropical Medicine, Manila, Philippines
| | | | - Marietjie Venter
- National Institute for Communicable Diseases, Johannesburg, South Africa
- Zoonoses Research Unit, Department Medical Virology, University of Pretoria, Pretoria, South Africa
- Division of Global Health Protection, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | | | | | | | - Andros Theo
- Virology Laboratory, University Teaching Hospital, Lusaka, Zambia
| | - Melissa Whaley
- Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Eduardo Azziz-Baumgartner
- Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Joseph Bresee
- Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Harry Campbell
- Centre for Global Health Research, University of Edinburgh, Edinburgh, United Kingdom
| | - Marc-Alain Widdowson
- Influenza Division, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
- * E-mail: (KEL); (MAW)
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20
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Gessner BD. Severe Acute Respiratory Illness in Sub-Saharan Africa. J Infect Dis 2015; 212:843-4. [PMID: 25712971 DOI: 10.1093/infdis/jiv104] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 02/17/2015] [Indexed: 11/13/2022] Open
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21
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Abstract
Vaccine probe studies have emerged in the past 15 years as a useful way to characterise disease. By contrast, traditional studies of vaccines focus on defining the vaccine effectiveness or efficacy. The underlying basis for the vaccine probe approach is that the difference in disease burden between vaccinated and unvaccinated individuals can be ascribed to the vaccine-specific pathogen. Vaccine probe studies can increase understanding of a vaccine's public health value. For instance, even when a vaccine has a seemingly low efficacy, a high baseline disease incidence can lead to a large vaccine-preventable disease burden and thus that population-based vaccine introduction would be justified. So far, vaccines have been used as probes to characterise disease syndromes caused by Haemophilus influenzae type b, pneumococcus, rotavirus, and early infant influenza. However, vaccine probe studies have enormous potential and could be used more widely in epidemiology, for example, to define the vaccine-preventable burden of malaria, typhoid, paediatric influenza, and dengue, and to identify causal interactions between different pathogens.
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Affiliation(s)
- Daniel R Feikin
- International Vaccine Access Center, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA; Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
| | - J Anthony G Scott
- KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya; London School of Hygiene and Tropical Medicine, London, UK
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22
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Gessner BD, Feikin DR. Vaccine preventable disease incidence as a complement to vaccine efficacy for setting vaccine policy. Vaccine 2014; 32:3133-8. [PMID: 24731817 DOI: 10.1016/j.vaccine.2014.04.019] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2014] [Revised: 03/28/2014] [Accepted: 04/02/2014] [Indexed: 01/09/2023]
Abstract
Traditionally, vaccines have been evaluated in clinical trials that establish vaccine efficacy (VE) against etiology-confirmed disease outcomes, a measure important for licensure. Yet, VE does not reflect a vaccine's public health impact because it does not account for relative disease incidence. An additional measure that more directly establishes a vaccine's public health value is the vaccine preventable disease incidence (VPDI), which is the incidence of disease preventable by vaccine in a given context. We describe how VE and VPDI can vary, sometimes in inverse directions, across disease outcomes and vaccinated populations. We provide examples of how VPDI can be used to reveal the relative public health impact of vaccines in developing countries, which can be masked by focus on VE alone. We recommend that VPDI be incorporated along with VE into the analytic plans of vaccine trials, as well as decisions by funders, ministries of health, and regulatory authorities.
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Affiliation(s)
- Bradford D Gessner
- Agence de Médecine Preventive, 164 Rue de Vaugirard, 75015 Paris, France.
| | - Daniel R Feikin
- International Vaccine Access Center, Department of International Health, Johns Hopkins School of Public Health, Baltimore, MD, USA; Division of Preparedness and Emerging Infections, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA.
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23
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Deen J, Ali M, Sack D. Methods to assess the impact of mass oral cholera vaccination campaigns under real field conditions. PLoS One 2014; 9:e88139. [PMID: 24516595 PMCID: PMC3917865 DOI: 10.1371/journal.pone.0088139] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
There is increasing interest to use oral cholera vaccination as an additional strategy to water and sanitation interventions against endemic and epidemic cholera. There are two internationally-available and WHO-prequalified oral cholera vaccines: an inactivated vaccine containing killed whole-cells of V. cholerae O1 with recombinant cholera toxin B-subunit (WC/rBS) and a bivalent inactivated vaccine containing killed whole cells of V. cholerae O1 and V. cholerae O139 (BivWC). The efficacy, effectiveness, direct and indirect (herd) protection conferred by WC/rBS and BivWC are well established. Yet governments may need local evidence of vaccine impact to justify and scale-up mass oral cholera vaccination campaigns. We discuss various approaches to assess oral cholera vaccine protection, which may be useful to policymakers and public health workers considering deployment and evaluation of the vaccine.
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Affiliation(s)
- Jacqueline Deen
- Menzies School of Health Research, Casuarina, Northern Territory, Australia
| | - Mohammad Ali
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - David Sack
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
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