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The Journal of Infectious Diseases Aug 2022A systematic literature review was conducted to summarize the mortality (overall and by disease severity factors) of US infants and children aged <5 years with...
BACKGROUND
A systematic literature review was conducted to summarize the mortality (overall and by disease severity factors) of US infants and children aged <5 years with respiratory syncytial virus (RSV) or all-cause bronchiolitis (ACB).
METHODS
Comprehensive, systematic literature searches were conducted; articles were screened using prespecified eligibility criteria. A standard risk of bias tool was used to evaluate studies. Mortality was extracted as the rate per 100 000 or the case fatality ratio (CFR; proportion of deaths among RSV/ACB cases).
RESULTS
Among 42 included studies, 36 evaluated inpatient deaths; 10 used nationally representative populations updated through 2013, and only 2 included late-preterm/full-term otherwise healthy infants and children. The RSV/ACB definition varied across studies (multiple International Classification of Diseases [ICD] codes; laboratory confirmation); no study reported systematic testing for RSV. No studies reported RSV mortality rates, while 3 studies provided ACB mortality rates (0.57-9.4 per 100 000). CFRs ranged from 0% to 1.7% for RSV (n = 15) and from 0% to 0.17% for ACB (n = 6); higher CFRs were reported among premature, intensive care unit-admitted, and publicly insured infants and children.
CONCLUSIONS
RSV mortality reported among US infants and children is variable. Current, nationally representative estimates are needed for otherwise healthy, late-preterm to full-term infants and children.
Topics: Bronchiolitis; Child; Child, Preschool; Data Collection; Hospitalization; Humans; Infant; Infant, Newborn; Respiratory Syncytial Virus Infections; Respiratory Syncytial Virus, Human
PubMed: 35968871
DOI: 10.1093/infdis/jiac226 -
The Lancet. Infectious Diseases Nov 2019Measles is an important cause of death in children, despite the availability of safe and cost-saving measles-containing vaccines (MCVs). The first MCV dose (MCV1) is... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Measles is an important cause of death in children, despite the availability of safe and cost-saving measles-containing vaccines (MCVs). The first MCV dose (MCV1) is recommended at 9 months of age in countries with ongoing measles transmission, and at 12 months in countries with low risk of measles. To assess whether bringing forward the age of MCV1 is beneficial, we did a systematic review and meta-analysis of the benefits and risks of MCV1 in infants younger than 9 months.
METHODS
For this systematic review and meta-analysis, we searched MEDLINE, EMBASE, Scopus, Proquest, Global Health, the WHO library database, and the WHO Institutional Repository for Information Sharing database, and consulted experts. We included randomised and quasi-randomised controlled trials, outbreak investigations, and cohort and case-control studies without restriction on publication dates, in which MCV1 was administered to infants younger than 9 months. We did the literature search on June 2, 2015, and updated it on Jan 14, 2019. We assessed: proportion of infants seroconverted, geometric mean antibody titre, avidity, cellular immunity, duration of immunity, vaccine efficacy, vaccine effectiveness, and safety. We used random-effects models to derive pooled estimates of the endpoints, where appropriate. We assessed methodological quality using the Grading of Recommendations, Assessment, Development, and Evaluation guidelines.
FINDINGS
Our search identified 1156 studies, of which 1071 were screened for eligibility. 351 were eligible for full-text screening, and data from 56 studies that met all inclusion criteria were used for analysis. The proportion of infants who seroconverted increased from 50% (95% CI 29-71) for those vaccinated with MCV1 at 4 months of age to 85% (69-97) for those were vaccinated at 8 months. The pooled geometric mean titre ratio for infants aged 4-8 months vaccinated with MCV1 compared with infants vaccinated with MCV1 at age 9 months or older was 0·46 (95% CI 0·33-0·66; I=99·9%, p<0·0001). Only one study reported on avidity and suggested that there was lower avidity and a shorter duration of immunity following MCV1 administration at 6 months of age than at 9 months of age (p=0·0016) or 12 months of age (p<0·001). No effect of age at MCV1 administration on cellular immunity was found. One study reported that vaccine efficacy against laboratory-confirmed measles virus infection was 94% (95% CI 74-98) in infants vaccinated with MCV1 at 4·5 months of age. The pooled vaccine effectiveness of MCV1 in infants younger than 9 months against measles was 58% (95% CI 9-80; I=84·9%, p<0·0001). The pooled vaccine effectiveness estimate from within-study comparisons of infants younger than 9 months vaccinated with MCV1 were 51% (95% CI -44 to 83; I=92·3%, p<0·0001), and for those aged 9 months and older at vaccination it was 83% (76-88; I=93·8%, p<0·0001). No differences in the risk of adverse events after MCV1 administration were found between infants younger than 9 months and those aged 9 months of older. Overall, the quality of evidence ranged from moderate to very low.
INTERPRETATION
MCV1 administered to infants younger than 9 months induces a good immune response, whereby the proportion of infants seroconverted increases with increased age at vaccination. A large proportion of infants receiving MCV1 before 9 months of age are protected and the vaccine is safe, although higher antibody titres and vaccine effectiveness are found when MCV1 is administered at older ages. Recommending MCV1 administration to infants younger than 9 months for those at high risk of measles is an important step towards reducing measles-related mortality and morbidity.
FUNDING
WHO.
Topics: Age Factors; Antibodies, Viral; Drug-Related Side Effects and Adverse Reactions; Female; Humans; Immunity, Cellular; Immunization Schedule; Infant; Male; Measles; Measles Vaccine; Measles virus; Risk Assessment; Treatment Outcome
PubMed: 31548079
DOI: 10.1016/S1473-3099(19)30395-0 -
Nutrients Oct 2022Vitamin A (VA) deficiency is associated with increased host susceptibility to infections, but evidence on its role in the prevention and management of viral infections... (Review)
Review
Vitamin A (VA) deficiency is associated with increased host susceptibility to infections, but evidence on its role in the prevention and management of viral infections is still lacking. This review aimed at summarizing the effects of VA supplementation against viral infections to support clinicians in evaluating supplemental treatments. PubMed, Scopus, and Web of Science were searched. Randomized clinical trials comparing the direct effects of VA oral supplementation in any form vs. placebo or standard of care in the prevention and/or management of confirmed viral infections in people of any age were included. A narrative synthesis of the results was performed. The revised Cochrane Risk-Of-Bias tool was used to assess quality. Overall, 40 articles of heterogeneous quality were included. We found data on infections sustained by ( = 17), ( = 2), ( = 1), ( = 3), ( = 4), and ( = 13). Studies were published between 1987 and 2017 and mostly conducted in Africa. The findings were heterogeneous across and within viral families regarding virological, immunological, and biological response, and no meaningful results were found in the prevention of viral infections. For a few diseases, VA-supplemented individuals had a better prognosis and improved outcomes, including clearance of HPV lesions or reduction in some measles-related complications. The effects of VA oral supplementation seem encouraging in relation to the management of a few viral infections. Difference in populations considered, variety in recruitment and treatment protocols might explain the heterogeneity of the results. Further investigations are needed to better identify the benefits of VA administration.
Topics: Dietary Supplements; Humans; Randomized Controlled Trials as Topic; Virus Diseases; Vitamin A; Vitamin D
PubMed: 36235733
DOI: 10.3390/nu14194081 -
Virulence Dec 2024Newcastle disease virus (NDV) typically induces severe illness in poultry and results in significant economic losses for the worldwide poultry sector. NDV, an RNA virus...
Newcastle disease virus (NDV) typically induces severe illness in poultry and results in significant economic losses for the worldwide poultry sector. NDV, an RNA virus with a single-stranded negative-sense genome, is susceptible to mutation and immune evasion during viral transmission, thus imposing enormous challenges to avian health and poultry production. NDV is composed of six structural proteins and two nonstructural proteins that exert pivotal roles in viral infection and antiviral responses by interacting with host proteins. Nowadays, there is a particular focus on the mechanisms of virus-host protein interactions in NDV research, yet a comprehensive overview of such research is still lacking. Herein, we briefly summarize the mechanisms regarding the effects of virus-host protein interaction on viral infection, pathogenesis, and host immune responses. This review can not only enhance the present comprehension of the mechanism underlying NDV and host interplay, but also furnish a point of reference for the advancement of antiviral measures.
Topics: Animals; Antiviral Agents; Host Microbial Interactions; Immune Evasion; Newcastle disease virus; Virus Diseases
PubMed: 38193514
DOI: 10.1080/21505594.2023.2299182 -
Nutrients Jan 2021Vitamin D is an essential component of immune function and childhood deficiency is associated with an increased risk of acute lower respiratory infections (ALRIs)....
Vitamin D is an essential component of immune function and childhood deficiency is associated with an increased risk of acute lower respiratory infections (ALRIs). Globally, the leading childhood respiratory pathogens are , respiratory syncytial virus and the influenza virus. There is a growing body of evidence describing the innate immunomodulatory properties of vitamin D during challenge with respiratory pathogens, but recent systematic and unbiased synthesis of data is lacking, and future research directions are unclear. We therefore conducted a systematic PubMed literature search using the terms "vitamin D" and "" or "Respiratory Syncytial Virus" or "Influenza". A priori inclusion criteria restricted the review to in vitro studies investigating the effect of vitamin D metabolites on human innate immune cells (primary, differentiated or immortalised) in response to stimulation with the specified respiratory pathogens. Eleven studies met our criteria. Despite some heterogeneity across pathogens and innate cell types, vitamin D modulated pathogen recognition receptor (PRRs: Toll-like receptor 2 (TLR2), TLR4, TLR7 and nucleotide-binding oligomerisation domain-containing protein 2 (NOD2)) expression; increased antimicrobial peptide expression (LL-37, human neutrophil peptide (HNP) 1-3 and β-defensin); modulated autophagosome production reducing apoptosis; and modulated production of inflammatory cytokines (Interleukin (IL) -1β, tumour necrosis factor-α (TNF-α), interferon-ɣ (IFN-ɣ), IL-12p70, IFN-β, Regulated on Activation, Normal T cell Expressed (RANTES), IL-10) and chemokines (IL-8 and C-X-C motif chemokine ligand 10 (CXCL10)). Differential modulation of PRRs and IL-1β was reported across immune cell types; however, this may be due to the experimental design. None of the studies specifically focused on immune responses in cells derived from children. In summary, vitamin D promotes a balanced immune response, potentially enhancing pathogen sensing and clearance and restricting pathogen induced inflammatory dysregulation. This is likely to be important in controlling both ALRIs and the immunopathology associated with poorer outcomes and progression to chronic lung diseases. Many unknowns remain and further investigation is required to clarify the nuances in vitamin D mediated immune responses by pathogen and immune cell type and to determine whether these in vitro findings translate into enhanced immunity and reduced ALRI in the paediatric clinical setting.
Topics: Child; Child, Preschool; Cytokines; Humans; Immunity, Innate; Immunomodulation; Infant; Influenza A virus; Influenza, Human; Pneumonia, Pneumococcal; Respiratory Syncytial Virus Infections; Respiratory Syncytial Viruses; Respiratory Tract Infections; Streptococcus pneumoniae; Vitamin D
PubMed: 33478006
DOI: 10.3390/nu13010276 -
Microbiology and Immunology Jan 2021Human parainfluenza virus (HPIV) infection is associated with every kind of respiratory tract illnesses, including the common cold, laryngotracheobronchitis (i.e.... (Review)
Review
Human parainfluenza virus (HPIV) infection is associated with every kind of respiratory tract illnesses, including the common cold, laryngotracheobronchitis (i.e. croup), tracheobronchitis, bronchiolitis, and pneumonia, in both children and adults. Although HPIVs are common respiratory pathogens, there are increasing reports about extrapulmonary manifestations of HPIVs infection. Each of the HPIVs could produce infection of other organs (central nervous system, heart, myocardium, etc.) in all age groups who are either immunocompetent or immunocompromised. This review aimed at summarizing the available data on clinical manifestations of HPIV infection outside the respiratory tract from 1961 to 2020. The findings support the possibility of extrapulmonary infections that were thought to be due to rare host genetic or immunologic defects in infected patients. These findings highlight the fact that extrapulmonary dissemination of HPIV can occur, but the association is not clearly demonstrated. Our data support the hypothesis that HPIV infection is one of the possible causes of these alterations and may even be the direct cause in some cases.
Topics: Adult; Central Nervous System; Child; Heart; Humans; Parainfluenza Virus 1, Human; Parainfluenza Virus 2, Human; Parainfluenza Virus 3, Human; Paramyxoviridae Infections; Pneumonia; Respiratory Tract Infections
PubMed: 33270253
DOI: 10.1111/1348-0421.12865 -
European Journal of Pediatrics Jan 2023Infections with respiratory syncytial virus (RSV) can cause severe disease. In young children, RSV is the most common cause of lower respiratory tract illness and...
UNLABELLED
Infections with respiratory syncytial virus (RSV) can cause severe disease. In young children, RSV is the most common cause of lower respiratory tract illness and life-threatening infections most commonly occur in the first years of life. In adults, elderly and immunocompromised people are most vulnerable. Recently there has been an acceleration in the development of candidate RSV vaccines, monoclonal antibodies and therapeutics which are expected to become available in Europe within the next 2-10 years. Understanding the true burden of childhood RSV disease will become very important to support public health authorities and policy makers in the assessment of new therapeutic opportunities against RSV disease. A systematic literature search was performed to map local data on the burden of RSV disease and to evaluate available RSV surveillance systems. A group of 9 paediatric infectious diseases specialists participated in an expert panel. The purpose of this meeting was to evaluate and map the burden associated with RSV infection in children, including patient pathways and the epidemiological patterns of virus circulation in Belgium. Sources of information on the burden of RSV disease in Belgium are very limited. For the outpatient setting, it is estimated that 5-10% of young patients seen in primary care are referred to the hospital. Around 3500 children between 0 and 12 months of age are hospitalized for RSV-bronchiolitis every year and represent the majority of all hospitalizations. The current Belgian RSV surveillance system was evaluated and found to be insufficient. Knowledge gaps are highlighted and future perspectives and priorities offered.
CONCLUSION
The Belgian population-based RSV surveillance should be improved, and a hospital-led reporting system should be put in place to enable the evaluation of the true burden of RSV disease in Belgium and to improve disease management in the future.
WHAT IS KNOWN
• RSV bronchiolitis is a very important cause of infant hospitalization. • The burden of disease in the community is poorly studied and underestimated.
WHAT IS NEW
• This expert opinion summarizes knowledge gaps and offers insights that allow improvement of local surveillance systems in order to establish a future-proof RSV surveillance system.
Topics: Humans; Infant; Infant, Newborn; Belgium; Bronchiolitis; Hospitalization; Population Surveillance; Respiratory Syncytial Virus Infections; Respiratory Syncytial Virus, Human
PubMed: 36371521
DOI: 10.1007/s00431-022-04698-z -
Transboundary and Emerging Diseases Nov 2022Given the avian metapneumovirus (aMPV) disease burden in poultry worldwide and the evidence of a possible role played by wild birds in the virus epidemiology, the... (Meta-Analysis)
Meta-Analysis
Given the avian metapneumovirus (aMPV) disease burden in poultry worldwide and the evidence of a possible role played by wild birds in the virus epidemiology, the present study summarizes aMPV serological and molecular data on free-ranging avifauna available in the literature by conducting a systematic review and meta-analysis. A computerized literature research was performed on PubMed, Scopus, CAB Direct and Web of Science to identify relevant publications across the period 1990-2021, along with the screening of reference lists. A random-effect model was applied to calculate pooled prevalence estimates with 95% confidence intervals. The inconsistency index statistic (I ) was applied to assess between-study heterogeneity. Subgroup analyses for molecular studies only were performed according to geographical area of samplings, taxonomic order, genus and migration patterns of the birds surveyed. A total of 11 publications on molecular surveys and 6 on serological ones were retained for analysis. The pooled molecular prevalence was 6% (95% CI: 1-13%) and a high between-study heterogeneity was detected (I = 96%, p < .01). Moderator analyses showed statistically significant differences according to geographical area studied, taxonomic order and genus. Concerning serological prevalence, a pooled estimate of 14% (95% CI: 1-39%), along with a high between-study heterogeneity, was obtained (I = 98%, p < .01). Moderator analysis was not performed due to the scarcity of eligible serological studies included. Overall, molecular and serological evidence suggests that some wild bird taxa could play a role in aMPV epidemiology. Particularly, wild ducks, geese, gulls and pheasants, according to scientific contributions hereby considered, proved to be susceptible to aMPV, and due to host ecology, may act as a viral carrier or reservoir. Further surveys of wild birds are encouraged for a better comprehension of the poultry/wild bird interface in aMPV epidemiology and for better characterizing the virus host breadth.
Topics: Animals; Metapneumovirus; Paramyxoviridae Infections; Animals, Wild; Ducks; Geese; Poultry Diseases; Chickens
PubMed: 35960706
DOI: 10.1111/tbed.14680 -
Journal of Clinical Virology : the... Aug 2019A wide range of Nipah virus (NiV) encephalitis case fatality rates (CFR) have been reported. Data on the involvement of several potential risk factors in Nipah virus... (Meta-Analysis)
Meta-Analysis
BACKGROUND
A wide range of Nipah virus (NiV) encephalitis case fatality rates (CFR) have been reported. Data on the involvement of several potential risk factors in Nipah virus transmission remain controversial. We performed a systematic review and meta-analysis to estimate the pooled CFR of NiV encephalitis and to assess the risk factors for NiV infection.
METHODS
Articles published up to the 27of November 2018 in MedLine, Embase and Web of knowledge databases were considered for this study. We included cross-sectional, cohort, and case-control studies that have reported NiV CFR and/or risk factors. Data were pooled with random-effects model. This review was registered in the PROSPERO, CRD42018116242.
FINDINGS
This global review included 22 citations (25 studies) including 2156, 1682, and 474 suspected, probable, and confirmed cases of NiV encephalitis, respectively. We determined a pooled CFR for NiV encephalitis at 61.0% (95% CI, 45.7-75.4; I² = 96.8%). Climbing trees (OR = 1.4; 95% CI; 1.0-1.9), male gender (OR = 1.5; 95% CI; 1.1-2.0), travel outside their own sub-district (OR = 2.0; 95% CI; 1.4-2.9), and exposure to date palm sap (DPS) (OR = 5.7; 95% CI; 3.8-8.6) or pigs (OR = 7.6; 95% CI; 1.2-45.4) were significantly associated with NiV infection.
CONCLUSION
Findings from this study suggest that NiV Encephalitis is associated with a high CFR and that male gender, travel outside their sub-district, climbing trees, and exposure to pigs and DPS are associated with an increased risk of NiV encephalitis.
Topics: Animals; Encephalitis, Viral; Female; Henipavirus Infections; Humans; Male; Mortality; Nipah Virus; Risk Factors; Sex Characteristics; Zoonoses
PubMed: 31132674
DOI: 10.1016/j.jcv.2019.05.009 -
The Journal of Infectious Diseases Aug 2022Respiratory syncytial virus (RSV) can cause serious illness in those aged <5 years in the United States, but uncertainty remains around which populations receive RSV...
BACKGROUND
Respiratory syncytial virus (RSV) can cause serious illness in those aged <5 years in the United States, but uncertainty remains around which populations receive RSV testing. We conducted a systematic literature review of RSV testing patterns in studies published from 2000 to 2021.
METHODS
Studies of RSV, medically attended RSV lower respiratory tract infections (LRTIs), and bronchiolitis were identified using standard methodology. Outcomes were clinical decisions to test for RSV, testing frequency, and testing incidence proportions in inpatient (IP), emergency department (ED), outpatient (OP), and urgent care settings.
RESULTS
Eighty good-/fair-quality studies, which reported data from the period 1988-2020, were identified. Twenty-seven described the clinical decision to test, which varied across and within settings. Two studies reported RSV testing frequency for multiple settings, with higher testing proportions in IP (n = 2, range: 83%-85%, 1996-2009) compared with ED (n = 1, 25%, 2006-2009) and OP (n = 2, 15%-25%, 1996-2009). Higher RSV testing incidence proportions were observed among LRTI infant populations in the ED (n = 1, 74%, 2007-2008) and OP (n = 2, 54%-69%, 1995-2008). Incidence proportions in LRTI populations were not consistently higher in the IP setting (n = 13). Across studies and time, there was heterogeneity in RSV testing patterns, which may reflect varying detection methods, populations, locations, time periods, and healthcare settings.
CONCLUSIONS
Not all infants and children with LRTI are tested for RSV, highlighting underestimation of RSV burden across all settings.
Topics: Bronchiolitis; Child; Child, Preschool; Humans; Incidence; Infant; Respiratory Syncytial Virus Infections; Respiratory Syncytial Virus, Human; Respiratory Tract Infections; United States
PubMed: 35968874
DOI: 10.1093/infdis/jiac203