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Piamonte BLC, Easton A, Wood GK, Davies NWS, Granerod J, Michael BD, Solomon T, Thakur KT. Addressing vaccine-preventable encephalitis in vulnerable populations. Curr Opin Neurol 2023; 36:185-197. [PMID: 37078664 DOI: 10.1097/wco.0000000000001158] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/21/2023]
Abstract
PURPOSE OF REVIEW Vaccinations have been pivotal in lowering the global disease burden of vaccine-preventable encephalitides, including Japanese encephalitis, tick-borne encephalitis, measles encephalitis, and rabies encephalitis, among others. RECENT FINDINGS Populations vulnerable to vaccine-preventable infections that may lead to encephalitis include those living in endemic and rural areas, military members, migrants, refugees, international travelers, younger and older persons, pregnant women, the immunocompromised, outdoor, healthcare and laboratory workers, and the homeless. There is scope for improving the availability and distribution of vaccinations, vaccine equity, surveillance of vaccine-preventable encephalitides, and public education and information. SUMMARY Addressing these gaps in vaccination strategies will allow for improved vaccination coverage and lead to better health outcomes for those most at risk for vaccine-preventable encephalitis.
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Affiliation(s)
- Bernadeth Lyn C Piamonte
- Department of Neurosciences, College of Medicine and Philippine General Hospital, University of the Philippines Manila, Manila, Philippines
| | - Ava Easton
- The Encephalitis Society, Malton
- Department of Clinical Infection, Microbiology, and Immunology, Institute of Infection, Veterinary and Ecological Sciences
| | - Greta K Wood
- Department of Clinical Infection, Microbiology, and Immunology, Institute of Infection, Veterinary and Ecological Sciences
- National Institute for Health Research Health Protection Research Unit in Emerging and Zoonotic Infection, University of Liverpool, Liverpool
| | - Nicholas W S Davies
- The Encephalitis Society, Malton
- Department of Neurology, Chelsea and Westminster Hospital, NHS Trust
| | - Julia Granerod
- Department of Clinical Infection, Microbiology, and Immunology, Institute of Infection, Veterinary and Ecological Sciences
- Dr JGW Consulting Ltd., London
| | - Benedict D Michael
- The Encephalitis Society, Malton
- Department of Clinical Infection, Microbiology, and Immunology, Institute of Infection, Veterinary and Ecological Sciences
- National Institute for Health Research Health Protection Research Unit in Emerging and Zoonotic Infection, University of Liverpool, Liverpool
- Department of Neurology, The Walton Centre NHS Foundation Trust
| | - Tom Solomon
- The Encephalitis Society, Malton
- Department of Clinical Infection, Microbiology, and Immunology, Institute of Infection, Veterinary and Ecological Sciences
- National Institute for Health Research Health Protection Research Unit in Emerging and Zoonotic Infection, University of Liverpool, Liverpool
- Department of Neurology, The Walton Centre NHS Foundation Trust
- Department of Neurological Science, University of Liverpool, Liverpool, United Kingdom
| | - Kiran T Thakur
- The Encephalitis Society, Malton
- Department of Neurology, Columbia University Irving Medical Center/New York Presbyterian Hospital, New York, USA
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Donnelley E, Teutsch S, Zurynski Y, Nunez C, Khandaker G, Lester-Smith D, Festa M, Booy R, Elliott EJ, Britton PN, Phu A, Handel D. Severe Influenza-Associated Neurological Disease in Australian Children: Seasonal Population-Based Surveillance 2008-2018. J Pediatric Infect Dis Soc 2022; 11:533-540. [PMID: 36153667 DOI: 10.1093/jpids/piac069] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 06/29/2022] [Indexed: 12/30/2022]
Abstract
BACKGROUND Influenza-associated neurological disease (IAND) is uncommon but can result in death or neurological morbidity in children. We aimed to describe the incidence, risk factors, and outcome of children with IAND from seasonal influenza in Australia. METHODS We analyzed national, population-based, surveillance data for children aged ≤ 14 years with severe influenza and neurological involvement, over 11 Australian influenza seasons, 2008-2018, by the Australian Paediatric Surveillance Unit. RESULTS There were 633 laboratory-confirmed cases of severe influenza reported. Of these, 165 (26%) had IAND. The average annual incidence for IAND was 3.39 per million children aged ≤ 14 years. Compared to cases without neurological complications, those with IAND were more likely to have a pre-existing neurological disease (odds ratio [OR] 3.03, P < .001), but most children with IAND did not (n = 135, 82%). Children with IAND were more likely to receive antivirals (OR 1.80, P = .002), require intensive care (OR 1.79, P = .001), require ventilation (OR 1.99; P = .001), and die (OR 2.83, P = .004). CONCLUSIONS IAND is a preventable cause of mortality, predominantly in otherwise well children. Incidence estimates validate previous sentinel site estimates from Australia. IAND accounted for a quarter of all severe influenza, is associated with intensive care unit admission, and accounted for half of all influenza deaths.
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Affiliation(s)
- Erin Donnelley
- Department of General Medicine, The Children's Hospital at Westmead, Westmead, New South Wales, Australia
| | - Suzy Teutsch
- Australian Paediatric Surveillance Unit, Kids Research, Sydney Children's Hospitals Network, Westmead, New South Wales, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Yvonne Zurynski
- Australian Paediatric Surveillance Unit, Kids Research, Sydney Children's Hospitals Network, Westmead, New South Wales, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.,Australian Institute of Health Innovation, National Health and Medical Research Council Partnership Centre for Health System Sustainability, Macquarie University, Sydney, New South Wales, Australia
| | - Carlos Nunez
- Australian Paediatric Surveillance Unit, Kids Research, Sydney Children's Hospitals Network, Westmead, New South Wales, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Gulam Khandaker
- Central Queensland Hospital and Health Service, Rockhampton, Queensland, Australia.,Research Division, Central Queensland University, Queensland, Australia
| | - David Lester-Smith
- Department of General Medicine, The Children's Hospital at Westmead, Westmead, New South Wales, Australia.,Australian Paediatric Surveillance Unit, Kids Research, Sydney Children's Hospitals Network, Westmead, New South Wales, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Marino Festa
- Department of Intensive Care Medicine, The Children's Hospital at Westmead, Westmead, New South Wales, Australia.,Kids Critical Care Research, The Children's Hospital at Westmead, Westmead, New South Wales, Australia
| | - Robert Booy
- Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.,National Centre for Immunisation Research and Surveillance, The Children's Hospital at Westmead, Westmead, New South Wales, Australia
| | - Elizabeth J Elliott
- Australian Paediatric Surveillance Unit, Kids Research, Sydney Children's Hospitals Network, Westmead, New South Wales, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Philip N Britton
- Australian Paediatric Surveillance Unit, Kids Research, Sydney Children's Hospitals Network, Westmead, New South Wales, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia.,Department of Infectious Diseases and Microbiology, The Children's Hospital at Westmead, Westmead, New South Wales, Australia
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Influenza-associated Neurologic Complications in Hospitalized Pediatric Patients: A Multicenter Retrospective Study in Republic of Korea. Pediatr Infect Dis J 2021; 40:e466-e471. [PMID: 34609108 DOI: 10.1097/inf.0000000000003332] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND The rates of influenza-associated neurologic complications are variable among studies, and a difference has been observed between the Western and Asian countries. The study aims to evaluate the frequency and characteristics of influenza-associated neurologic complications. METHODS We performed a retrospective review of hospitalized cases of influenza infection from October 2010 to April 2017 from 3 referral hospitals. RESULTS A total of 1988 influenza cases were identified. Influenza-associated neurologic complications were 161 cases (8.1%); influenza virus A was detected in 113 (70.2%) cases, B in 47 (29.2%) cases and both A and B in 1 case (0.6%). Twenty-four patients (15%) had underlying neurologic diseases. The most common diagnosis was a simple febrile convulsion (44%), followed by complex febrile convulsion (29%), fever-provoked seizure under pre-existing neurologic disease or afebrile seizure (14%), encephalopathy/encephalitis (8%) and meningitis (5%). Most of the patients fully recovered (96%). Three patients (1.9%) died of myocarditis (n = 1), encephalopathy (n = 1), and simultaneous encephalitis and myocarditis (n = 1). Pre-existing neurologic disease, age groups of 6 months to 6 years and 6-12 years were a risk factor of influenza-associated neurologic complications with an adjusted odds ratio of 5.41 (95% confidence interval [CI] 3.23-9.06, P < 0.001), 12.99 (95% CI 1.77-95.19, P = 0.01) and 8.54 (95% CI 1.14-64.79, P = 0.04), respectively. There was no association between neuropsychiatric adverse events and oseltamivir prescription (P = 0.17). CONCLUSIONS Influenza-associated neurologic complications are not uncommon, and most patients fully recovered. The frequency of influenza-associated neurologic complications in Korean children was not significantly different from that of children in Western countries.
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Dumm RE, Wellford SA, Moseman EA, Heaton NS. Heterogeneity of Antiviral Responses in the Upper Respiratory Tract Mediates Differential Non-lytic Clearance of Influenza Viruses. Cell Rep 2020; 32:108103. [PMID: 32877682 PMCID: PMC7462569 DOI: 10.1016/j.celrep.2020.108103] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2020] [Revised: 06/01/2020] [Accepted: 08/11/2020] [Indexed: 01/06/2023] Open
Abstract
Influenza viruses initiate infection in the upper respiratory tract (URT), but early viral tropism and the importance of cell-type-specific antiviral responses in this tissue remain incompletely understood. By infecting transgenic lox-stop-lox reporter mice with a Cre-recombinase-expressing influenza B virus, we identify olfactory sensory neurons (OSNs) as a major viral cell target in the URT. These cells become infected, then eliminate the virus and survive in the host post-resolution of infection. OSN responses to infection are characterized by a strong induction of interferon-stimulated genes and more rapid clearance of viral protein relative to other cells in the epithelium. We speculate that this cell-type-specific response likely serves to protect the central nervous system from infection. More broadly, these results highlight the importance of evaluating antiviral responses across different cell types, even those within the same tissue, to more fully understand the mechanisms of viral disease.
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Affiliation(s)
- Rebekah E Dumm
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA
| | - Sebastian A Wellford
- Department of Immunology, Duke University School of Medicine, Durham, NC 27710, USA
| | - E Ashley Moseman
- Department of Immunology, Duke University School of Medicine, Durham, NC 27710, USA.
| | - Nicholas S Heaton
- Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC 27710, USA; Duke Human Vaccine Institute, Duke University School of Medicine, Durham, NC 27710, USA.
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Mastrolia MV, Rubino C, Resti M, Trapani S, Galli L. Characteristics and outcome of influenza-associated encephalopathy/encephalitis among children in a tertiary pediatric hospital in Italy, 2017-2019. BMC Infect Dis 2019; 19:1012. [PMID: 31783806 PMCID: PMC6884834 DOI: 10.1186/s12879-019-4636-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 11/18/2019] [Indexed: 12/20/2022] Open
Abstract
Background Influenza is the most frequent cause of acute upper respiratory tract infections during winter season. Although rare, neurological manifestations are known to occur during influenza infection and approximatively three-quarters of cases are in children. In this study, we aimed to characterize the burden and clinical spectrum of influenza-associated encephalopathy and encephalitis in children admitted at a tertiary pediatric hospital in Italy over two influenza seasons (2017–2019). Methods We retrospectively analyzed clinical, laboratory, instrumental data and outcome of patients discharged with ICD9-CM 487.0 code. Results Fifteen children (13.1% of those discharged with a diagnosis of influenza infection in the study period), had influenza-associated central nervous system (CNS) manifestations. Eight patients (53.3%) were diagnosed as influenza encephalitis, 7 (46.7%) as influenza encephalopathy. Median age was 27 months. In children under 2 years of age (40% of all cases) altered consciousness was the most frequent neurological manifestation while respiratory symptoms were present at admission in all cases. Younger children also required intensive care support more frequently. Five subjects (33.3%) presented comorbidity. None of the patients had received seasonal influenza vaccination. The median time from onset of respiratory signs to onset of neurological manifestations was 24 h. Cerebrospinal fluid (CSF) analysis was normal in most patients and polymerase chain reaction for influenza virus RNA on CSF, when performed, was negative in all samples. Neuroradiological investigations, performed in 5 children, reported cortical and subcortical white matter signal alterations. Oseltamivir was administered only in 2 cases. Fourteen patients recovered without sequelae, and only a 2-year-old girl had minimal impairment in fine motor skills at discharge. Conclusions All children presenting acute neurological features during influenza season should be evaluated for influenza-associated CNS complications even if the respiratory involvement is mild. Absence of underlying diseases or other risk factors are not protective factors against CNS influenza-associated complications. The lack of CSF pleocytosis does not exclude CNS involvement. Children under 2 years of age are at higher risk of requiring intensive care support.
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Affiliation(s)
- Maria Vincenza Mastrolia
- Post-graduate School of Pediatrics, University of Florence, Viale Gaetano Pieraccini, 24, 50139, Florence, Italy.
| | - Chiara Rubino
- Post-graduate School of Pediatrics, University of Florence, Viale Gaetano Pieraccini, 24, 50139, Florence, Italy
| | - Massimo Resti
- Pediatric Department, Anna Meyer Children's University Hospital, Florence, Italy
| | - Sandra Trapani
- Pediatric Department, Anna Meyer Children's University Hospital, Florence, Italy
| | - Luisa Galli
- Department of Health Sciences University of Florence, Paediatric Infectious Diseases Division, Anna Meyer Children's University Hospital, Florence, Italy
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Britton PN, Blyth CC, Macartney K, Dale RC, Li-Kim-Moy J, Khandaker G, Crawford NW, Marshall H, Clark JE, Elliott EJ, Booy R, Cheng AC, Jones CA. The Spectrum and Burden of Influenza-Associated Neurological Disease in Children: Combined Encephalitis and Influenza Sentinel Site Surveillance From Australia, 2013-2015. Clin Infect Dis 2018; 65:653-660. [PMID: 29017268 DOI: 10.1093/cid/cix412] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 04/27/2017] [Indexed: 11/14/2022] Open
Abstract
Background There are few longitudinal studies of seasonal influenza-associated neurological disease (IAND) and none from the Southern Hemisphere. Methods We extracted prospectively acquired Australian surveillance data from 2 studies nested within the Paediatric Active Enhanced Disease Surveillance (PAEDS) network: the Influenza Complications Alert Network (FluCAN) study and the Australian Childhood Encephalitis (ACE) study between 2013 and 2015. We described the clinical features and severity of IAND in children, including influenza-associated encephalitis/encephalopathy (IAE). We calculated the proportion of hospitalized influenza that is associated with IAND and IAE, and incidence of IAE. Results Over 3 influenza seasons, we identified 54 cases of IAND at 2 tertiary children's hospitals from Australia that accounted for 7.6% of hospitalized influenza. These included 10 cases of IAE (1.4% hospitalized influenza). The mean annual incidence of IAE among Australian children (aged ≤14 years) was 2.8 per 1000000. The spectrum of IAND was broad and included IAE (n = 10) including distinct acute encephalopathy syndromes, simple febrile seizures (n = 14), other seizures (n = 16), acute ataxia (n = 4), and other subacute syndromes (transverse myelitis [n = 1], opsoclonus myoclonus [n = 1]). Two-thirds of children with IAND were aged ≤4 years; less than half had preexisting neurological disease or other risk factors for severe influenza. IAE caused death or neurological morbidity in half of cases. Conclusions Seasonal influenza is an important cause of acute neurological disease in Australian children. The spectrum of seasonal IAND appears similar to that described during the 2009 H1N1 pandemic. IAE is associated with high morbidity and mortality.
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Affiliation(s)
- Philip N Britton
- Sydney Medical School, University of Sydney, NSW.,Marie Bashir Institute of Infectious Diseases and Biosecurity, University of Sydney.,Children's Hospital at Westmead, New South Wales
| | - Christopher C Blyth
- Department of Infectious Diseases and Department of Microbiology, Princess Margaret Hospital, Subiaco.,Department of Microbiology, PathWest Laboratory, Nedlands, Western Australia.,School of Medicine, University of Western Australia.,Wesfarmers Centre for Vaccines and Infectious Diseases, Telethon Kids Institute
| | - Kristine Macartney
- Sydney Medical School, University of Sydney, NSW.,Marie Bashir Institute of Infectious Diseases and Biosecurity, University of Sydney.,Children's Hospital at Westmead, New South Wales.,National Centre for Immunisation Research and Surveillance, Westmead, New South Wales
| | - Russell C Dale
- Sydney Medical School, University of Sydney, NSW.,Children's Hospital at Westmead, New South Wales
| | - Jean Li-Kim-Moy
- Sydney Medical School, University of Sydney, NSW.,Children's Hospital at Westmead, New South Wales.,National Centre for Immunisation Research and Surveillance, Westmead, New South Wales
| | - Gulam Khandaker
- Sydney Medical School, University of Sydney, NSW.,National Centre for Immunisation Research and Surveillance, Westmead, New South Wales
| | - Nigel W Crawford
- Royal Children's Hospital, Melbourne, Victoria.,Murdoch Children's Research Institute and University of Melbourne, Victoria
| | - Helen Marshall
- Women's and Children's Hospital, Adelaide Medical School, University of Adelaide, South Australia
| | - Julia E Clark
- Lady Cilento Children's Hospital, Queensland.,School of Medicine, University of Queensland, Brisbane
| | - Elizabeth J Elliott
- Sydney Medical School, University of Sydney, NSW.,Australian Paediatric Surveillance Unit, Westmead, New South Wales
| | - Robert Booy
- Sydney Medical School, University of Sydney, NSW.,Marie Bashir Institute of Infectious Diseases and Biosecurity, University of Sydney.,Children's Hospital at Westmead, New South Wales.,National Centre for Immunisation Research and Surveillance, Westmead, New South Wales
| | - Allen C Cheng
- School of Public Health and Preventive Medicine, Monash University.,Infection Prevention and Healthcare Epidemiology Unit, Alfred Health, Melbourne, Victoria, Australia
| | - Cheryl A Jones
- Sydney Medical School, University of Sydney, NSW.,Marie Bashir Institute of Infectious Diseases and Biosecurity, University of Sydney.,Royal Children's Hospital, Melbourne, Victoria.,Murdoch Children's Research Institute and University of Melbourne, Victoria
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Vision Loss Caused by Retinal and Lateral Geniculate Nucleus Infarction in H1N1 Influenza. J Neuroophthalmol 2016; 35:265-9. [PMID: 25887303 DOI: 10.1097/wno.0000000000000247] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
A 13-year-old girl developed encephalopathy and severe bilateral vision loss to the level of light perception within 24 hours of having fever and myalgias heralding H1N1 influenza A. Ophthalmoscopy demonstrated findings of confluent ischemic retinopathy. Brain MRI disclosed lateral geniculate body signal abnormalities indicative of hemorrhagic infarction. Despite aggressive treatment with intravenous corticosteroids, intravenous immunoglobulin, and plasmapheresis, vision did not substantially improve. This case demonstrates that H1N1 can cause simultaneous retinal and lateral geniculate body infarctions, a combination of findings not previously described in any condition. We postulate an immunologic response to the virus marked by occlusive damage to arteriolar endothelium.
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A review of the evidence to support influenza vaccine introduction in countries and areas of WHO's Western Pacific Region. PLoS One 2013; 8:e70003. [PMID: 23875015 PMCID: PMC3713047 DOI: 10.1371/journal.pone.0070003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2013] [Accepted: 06/17/2013] [Indexed: 11/24/2022] Open
Abstract
Background Immunization against influenza is considered an essential public health intervention to control both seasonal epidemics and pandemic influenza. According to the World Health Organization (WHO), there are five key policy and three key programmatic issues that decision-makers should consider before introducing a vaccine. These are (a) public health priority, (b) disease burden, (c) efficacy, quality and safety of the vaccine, (d) other inventions, (e) economic and financial issues, (f) vaccine presentation, (g) supply availability and (h) programmatic strength. We analyzed the body of evidence currently available on these eight issues in the WHO Western Pacific Region. Methodology/Principal Findings Studies indexed in PubMed and published in English between 1 January 2000 and 31 December 2010 from the 37 countries and areas of the Western Pacific Region were screened for keywords pertaining to the five policy and three programmatic issues. Studies were grouped according to country income level and vaccine target group. There were 133 articles that met the selection criteria, with most (90%) coming from high-income countries. Disease burden (n = 34), vaccine efficacy, quality and safety (n = 27) and public health priority (n = 27) were most frequently addressed by studies conducted in the Region. Many studies assessed influenza vaccine policy and programmatic issues in the general population (42%), in the elderly (24%) and in children (17%). Few studies (2%) addressed the eight issues relating to pregnant women. Conclusions/Significance The evidence for vaccine introduction in countries and areas in this Region remains limited, particularly in low- and middle-income countries that do not currently have influenza vaccination programmes. Surveillance activities and specialized studies can be used to assess the eight issues including disease burden among vaccine target groups and the cost-effectiveness of influenza vaccine. Multi-country studies should be considered to maximize resource utilization for cross-cutting issues such as vaccine presentation and other inventions.
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Sugaya N, Takeuchi Y. Mass Vaccination of Schoolchildren against Influenza and Its Impact on the Influenza-Associated Mortality Rate among Children in Japan. Clin Infect Dis 2005; 41:939-47. [PMID: 16142657 DOI: 10.1086/432938] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2005] [Accepted: 06/01/2005] [Indexed: 11/03/2022] Open
Abstract
BACKGROUND Influenza control based on mass vaccination of schoolchildren was implemented in Japan in the 1960s and was associated with a decrease in the overall mortality rate. The program was discontinued in 1994. The discontinuation was followed by a seasonal increase in the mortality rate. Lately, young children and elderly persons have been receiving influenza vaccines. The purpose of this study was to investigate changes in influenza-related mortality among young children before and after discontinuation of mass vaccination of schoolchildren. METHODS We calculated the monthly all-cause mortality rates during 1972-2003 and the pneumonia and influenza (P&I) mortality rates during 1972-1999 for young children (age, 1-4 years). We estimated the excess mortality rates attributable to influenza by computing the baseline annual mortality rate as a centered, 3-year moving average of the number of deaths reported during the 2 preceding and the following Decembers. RESULTS Prominent winter peaks in monthly all-cause mortality rates among young children occurred in the 1990s. They coincided with the winter peaks in monthly P&I mortality rates among young children and were very similar to the winter peaks observed among elderly persons. The number of excess deaths of young children was estimated to be 783 in the 11 winter seasons from 1990 to 2000, whereas no winter peaks in the number of deaths were seen after 2000. CONCLUSIONS It is likely that discontinuation of mass vaccination of schoolchildren was responsible for the increase in influenza-associated deaths among young children in the 1990s. The recent increase in influenza vaccinations among young children, together with the routine therapeutic use of neuraminidase inhibitors, has led to a decrease in the influenza-associated mortality rate.
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Affiliation(s)
- Norio Sugaya
- Department of Pediatrics, Keiyu Hospital, Yokohama, Kanagawa, Japan.
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Okamoto S, Kamiya I, Kishida K, Shimakawa T, Fukui T, Morimoto T. Experience with oseltamivir for infants younger than 1 year old in Japan. Pediatr Infect Dis J 2005; 24:575-6. [PMID: 15933579 DOI: 10.1097/01.inf.0000164799.33635.fe] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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