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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 -
Treatment interventions for diarrhoea in HIV-infected and HIV-exposed children: a systematic review.The Pan African Medical Journal 2018Seventy percent of an estimated 10 million children less than five years of age in developing countries die each year of acute respiratory infections, diarrhoea,... (Review)
Review
INTRODUCTION
Seventy percent of an estimated 10 million children less than five years of age in developing countries die each year of acute respiratory infections, diarrhoea, measles, malaria, malnutrition or a combination of these conditions. Children living with Human immunodeficiency virus (HIV) are at risk of diarrhoea because of drug interactions with antiretroviral therapy and bottle feeding. This may be aggravated by malnutrition and other infectious diseases which are frequent in children living with HIV. Objective: to evaluate treatment interventions for diarrhoea in HIV infected and exposed children.
METHODS
A comprehensive search was conducted on 02 June 2016 to identify relevant studies for inclusion. We included randomised controlled trials of HIV infected or exposed children under 15 years of age with diarrhoea. Two authors independently selected studies for inclusion, assessed risk of bias (RoB) and extracted data using a pre-designed data extraction form.
RESULTS
We included two studies (Amadi 2002 and Mda 2010) that each enrolled 50 participants. The RoB was assessed as low-risk for both included studies. There was no difference in clinical cure and all-cause mortality between nitazoxanide and placebo for cryptosporidial diarrhoea in Amadi 2002. In Mda 2010, there was a reduction in duration of hospitalisation in the micronutrient supplement group (P < 0.005) although there was no difference in all-cause mortality.
CONCLUSION
There is low certainty evidence on the effectiveness of nitazoxanide for treating cryptosporidial diarrhoea and micronutrient supplementation in children with diarrhoea. Adequately powered trials are needed to assess micronutrients and nitazoxanide, as well as other interventions, for diarrhoea in HIV-infected and-exposed children.
Topics: Adolescent; Anti-HIV Agents; Antiparasitic Agents; Child; Child, Preschool; Cryptosporidiosis; Diarrhea; Dietary Supplements; Drug Interactions; HIV Infections; Humans; Micronutrients; Nitro Compounds; Randomized Controlled Trials as Topic; Thiazoles
PubMed: 30100962
DOI: 10.11604/pamj.2018.29.208.15240 -
BMC Infectious Diseases May 2018Information on the incubation period and period of infectiousness or shedding of infectious pathogens is critical for management and control of communicable diseases in...
BACKGROUND
Information on the incubation period and period of infectiousness or shedding of infectious pathogens is critical for management and control of communicable diseases in schools and other childcare settings.
METHODS
We performed a systematic literature review (Pubmed and Embase) to identify and critically appraise all relevant published articles using incubation, infectiousness or shedding, and exclusion period as parameters for the search. No language, time, geographical or study design restrictions were applied.
RESULTS
A total of 112 articles met the eligibility criteria. A relatively large number were retrieved for gastrointestinal diseases and influenza or respiratory syncytial virus, but there were few or no studies for other diseases. Although a considerable number of publications reported the incubation and shedding periods, there was less evidence concerning the period of infectiousness. On average, five days of exclusion is considered for measles, mumps, rubella, varicella and pertussis. For other diseases, such as most cases of meningococcal disease, hepatitis A and influenza exclusion is considered as long as severe symptoms persist. However, these results are based on a diverse range of study characteristics, including age, treatment, vaccination, underlying diseases, diagnostic tools, viral load, study design and definitions, making statistical analysis difficult.
CONCLUSIONS
Despite inconsistent definitions for key variables and the diversity of studies reviewed, published data provide sufficient quantitative estimates to inform decision making in schools and other childcare settings. The results can be used as a reference when deciding about the exclusion of a child with a communicable disease that both prevents exposure and avoids unnecessary absenteeism.
Topics: Adolescent; Chickenpox; Child; Child Care; Child, Preschool; Communicable Disease Control; Communicable Diseases; Hepatitis A; Humans; Infant; Infectious Disease Incubation Period; Influenza, Human; Measles; Mumps; Rubella; Schools; Vaccination; Whooping Cough
PubMed: 29716545
DOI: 10.1186/s12879-018-3095-8 -
Human Vaccines & Immunotherapeutics Feb 2017Asplenic or hyposplenic (AH) individuals are particularly vulnerable to invasive infections caused by encapsulated bacteria. Such infections have often a sudden onset... (Review)
Review
Asplenic or hyposplenic (AH) individuals are particularly vulnerable to invasive infections caused by encapsulated bacteria. Such infections have often a sudden onset and a fulminant course. Infectious diseases (IDs) incidence in AH subjects can be reduced by preventive measures such as vaccination. The aim of our work is to provide updated recommendations on prevention of infectious diseases in AH adult patients, and to supply a useful and practical tool to healthcare workers for the management of these subjects, in hospital setting and in outpatients consultation. A systematic literature review on evidence based measures for the prevention of IDs in adult AH patients was performed in 2015. Updated recommendations on available vaccines were consequently provided. Vaccinations against S. pneumoniae, N. meningitidis, H. influenzae type b and influenza virus are strongly recommended and should be administered at least 2 weeks before surgery in elective cases or at least 2 weeks after the surgical intervention in emergency cases. In subjects without evidence of immunity, 2 doses of live attenuated vaccines against measles-mumps-rubella and varicella should be administered 4-8 weeks apart from each other; a booster dose of tetanus, diphtheria and pertussis vaccine should be administered also to subjects fully vaccinated, and a 3-dose primary vaccination series is recommended in AH subjects with unknown or incomplete vaccination series (as in healthy people). Evidence based prevention data support the above recommendations to reduce the risk of infection in AH individuals.
Topics: Adult; Disease Transmission, Infectious; Humans; Immunologic Deficiency Syndromes; Orthomyxoviridae; Splenic Diseases; Vaccination; Vaccines
PubMed: 27929751
DOI: 10.1080/21645515.2017.1264797 -
Human Vaccines & Immunotherapeutics Feb 2017Healthcare Workers (HCWs) have an increased risk both to acquire and to spread vaccine preventable diseases (VPDs) both to their colleagues and, especially, to... (Review)
Review
Susceptibility to vaccine-preventable diseases and vaccination adherence among healthcare workers in Italy: A cross-sectional survey at a regional acute-care university hospital and a systematic review.
Healthcare Workers (HCWs) have an increased risk both to acquire and to spread vaccine preventable diseases (VPDs) both to their colleagues and, especially, to vulnerable patients. The prevention of occupational hazards among HCWs is based on proper adoption of the standard and additional precautions, immunizations, and secondary preventive measures, such as post-exposure prophylaxis. Moreover, HCWs are often referred to as the most trusted source of vaccine-related information for their patients. In the present article, we report the findings of a cross-sectional study investigating the compliance to vaccinations among HCWs employed at the Obstetric Unit of a regional acute-care University Hospital in Northern Italy. Furthermore, a systematic review of the literature for some VPDs (i.e., HBV, measles, rubella, varicella and influenza) was performed, over a 17-year period, in order to update the socio-demographic and professional characteristics, the susceptibility status and the vaccination rates among HCWs in Italy.
Topics: Adult; Aged; Communicable Diseases; Cross-Sectional Studies; Disease Susceptibility; Female; Guideline Adherence; Health Personnel; Hospitals, University; Humans; Italy; Male; Middle Aged; Vaccination
PubMed: 27924688
DOI: 10.1080/21645515.2017.1264746 -
BMJ (Clinical Research Ed.) Oct 2016To identify and characterise non-specific immunological effects after routine childhood vaccines against BCG, measles, diphtheria, pertussis, and tetanus. (Review)
Review
OBJECTIVE
To identify and characterise non-specific immunological effects after routine childhood vaccines against BCG, measles, diphtheria, pertussis, and tetanus.
DESIGN
Systematic review of randomised controlled trials, cohort studies, and case-control studies.
DATA SOURCES
Embase, PubMed, Cochrane library, and Trip searched between 1947 and January 2014. Publications submitted by a panel of experts in the specialty were also included.
ELIGIBILITY CRITERIA FOR SELECTING STUDIES
All human studies reporting non-specific immunological effects after vaccination with standard childhood immunisations. Studies using recombinant vaccines, no vaccine at all, or reporting only vaccine specific outcomes were excluded. The primary aim was to systematically identify, assemble, and review all available studies and data on the possible non-specific or heterologous immunological effects of BCG; measles; mumps, measles, and rubella (MMR); diphtheria; tetanus; and pertussis vaccines.
RESULTS
The initial search yielded 11 168 references; 77 manuscripts met the inclusion criteria for data analysis. In most included studies (48%) BCG was the vaccine intervention. The final time point of outcome measurement was primarily performed (70%) between one and 12 months after vaccination. There was a high risk of bias in the included studies, with no single study rated low risk across all assessment criteria. A total of 143 different immunological variables were reported, which, in conjunction with differences in measurement units and summary statistics, created a high number of combinations thus precluding any meta-analysis. Studies that compared BCG vaccinated with unvaccinated groups showed a trend towards increased IFN-γ production in vitro in the vaccinated groups. Increases were also observed for IFN-γ measured after BCG vaccination in response to in vitro stimulation with microbial antigens from Candida albicans, tetanus toxoid, Staphylococcus aureas, lipopolysaccharide, and hepatitis B. Cohort studies of measles vaccination showed an increase in lymphoproliferation to microbial antigens from tetanus toxoid and C albicans Increases in immunogenicity to heterologous antigens were noted after diphtheria-tetanus (herpes simplex virus and polio antibody titres) and diphtheria-tetanus-pertussis (pneumococcus serotype 14 and polio neutralising responses) vaccination.
CONCLUSIONS
The papers reporting non-specific immunological effects had heterogeneous study designs and could not be conventionally meta-analysed, providing a low level of evidence quality. Some studies, such as BCG vaccine studies examining in vitro IFN-γ responses and measles vaccine studies examining lymphoproliferation to microbial antigen stimulation, showed a consistent direction of effect suggestive of non-specific immunological effects. The quality of the evidence, however, does not provide confidence in the nature, magnitude, or timing of non-specific immunological effects after vaccination with BCG, diphtheria, pertussis, tetanus, or measles containing vaccines nor the clinical importance of the findings.
Topics: BCG Vaccine; Case-Control Studies; Child, Preschool; Communicable Disease Control; Diphtheria; Diphtheria-Tetanus-Pertussis Vaccine; Female; Humans; Immunization; Infant; Male; Measles; Measles Vaccine; Measles-Mumps-Rubella Vaccine; Randomized Controlled Trials as Topic; Tetanus; Tuberculosis; United Kingdom; Vaccination; Whooping Cough
PubMed: 27737830
DOI: 10.1136/bmj.i5225 -
The Cochrane Database of Systematic... Aug 2016Reduced vitamin A concentration increases the risk of blindness in children infected with the measles virus. Promoting vitamin A supplementation in children with measles... (Review)
Review
BACKGROUND
Reduced vitamin A concentration increases the risk of blindness in children infected with the measles virus. Promoting vitamin A supplementation in children with measles contributes to the control of blindness in children, which is a high priority within the World Health Organization (WHO) VISION 2020 The Right to Sight Program.
OBJECTIVES
To assess the efficacy of vitamin A in preventing blindness in children with measles without prior clinical features of vitamin A deficiency.
SEARCH METHODS
We searched CENTRAL 2015, Issue 11, MEDLINE (1950 to December week 3, 2015), Embase (1974 to December 2015) and LILACS (1985 to December 2015).
SELECTION CRITERIA
Randomised controlled trials (RCTs) assessing the efficacy of vitamin A in preventing blindness in well-nourished children diagnosed with measles but with no prior clinical features of vitamin A deficiency.
DATA COLLECTION AND ANALYSIS
For the original review, two review authors independently assessed studies for eligibility and extracted data on reported outcomes. We contacted trial authors of the included studies for additional information on unpublished data. We included two RCTs which were clinically heterogenous. We presented the continuous outcomes reported as the mean difference (MD) with 95% confidence interval (CI) and dichotomous outcomes as risk ratio (RR) with 95% CI. Due to marked clinical heterogeneity we considered it inappropriate to perform a meta-analysis.
MAIN RESULTS
For the first publication of this review, two RCTs involving 260 children with measles which compared vitamin A with placebo met the inclusion criteria. Neither study reported blindness or other ocular morbidities as end points. One trial of moderate quality suggested evidence of a significant increase in serum retinol levels in the vitamin A group one week after two doses of vitamin A (MD 9.45 µg/dL, 95% CI 2.19 to 16.71; 17 participants, moderate-quality evidence), but not six weeks after three doses of vitamin A (MD 2.56 µg/dL, 95% CI -5.28 to 10.40; 39 participants, moderate-quality evidence). There was no significant difference in weight gain six weeks (MD 0.39 kg, -0.04 to 0.82; 48 participants, moderate-quality evidence) and six months (MD 0.52 kg, 95% CI -0.08 to 1.12; 36 participants, moderate-quality evidence) after three doses of vitamin A.The second trial found no significant difference in serum retinol levels two weeks after a single dose of vitamin A (MD 2.67 µg/dL, 95% CI -0.29 to 5.63; 155 participants, moderate-quality evidence). Percentage of undernutrition between the two groups did not differ significantly at one week (RR 0.93, 95% CI 0.56 to 1.54, 145 participants) and two weeks (RR 0.82, 95% CI 0.52 to 1.29, 147 participants) after a single dose of vitamin A. No adverse event was reported in either study. We did not find any new RCTS for this second update.
AUTHORS' CONCLUSIONS
We did not find any trials assessing whether or not vitamin A supplementation in children with measles prevents blindness, as neither study reported blindness or other ocular morbidities as end points.
Topics: Adolescent; Blindness; Child; Child, Preschool; Humans; Infant; Measles; Randomized Controlled Trials as Topic; Vitamin A; Vitamins
PubMed: 27580345
DOI: 10.1002/14651858.CD007719.pub4 -
International Journal of Public Health Sep 2016Despite the availability of vaccines and the existence of public vaccination recommendations, outbreaks of vaccine-preventable childhood diseases still cause public... (Review)
Review
OBJECTIVES
Despite the availability of vaccines and the existence of public vaccination recommendations, outbreaks of vaccine-preventable childhood diseases still cause public health debate. The objective of this systematic review was to provide an overview of the current epidemiology and economic burden of measles, mumps, pertussis, and varicella in Germany.
METHODS
We systematically reviewed studies published since 2000. The literature search was conducted using PubMed and EMBASE. Also, we used German notification data to give an up-to-date overview of the epidemiology of the four diseases under consideration.
RESULTS
Thirty-six studies were included in our review. Results suggest that there is still considerable morbidity due to childhood diseases in Germany. Studies providing cost estimates are scarce. Comparative analyses of different data sources (notification data vs. claims data) revealed a potential underestimation of incidence estimates when using notification data. Furthermore, several studies showed regional differences in incidence of some of the diseases under consideration.
CONCLUSIONS
Our findings underline the need for improved vaccination and communication strategies targeting all susceptible age and risk groups on a national and local level.
Topics: Chickenpox; Chickenpox Vaccine; Germany; Humans; Incidence; Measles; Measles-Mumps-Rubella Vaccine; Mumps; Vaccines, Combined; Virus Diseases; Whooping Cough
PubMed: 27488917
DOI: 10.1007/s00038-016-0842-8 -
BMC Veterinary Research May 2016Canine distemper virus (CDV) is the etiological agent of one of the most infectious diseases of domestic dogs, also known as a highly prevalent viral infectious disease... (Review)
Review
BACKGROUND
Canine distemper virus (CDV) is the etiological agent of one of the most infectious diseases of domestic dogs, also known as a highly prevalent viral infectious disease of carnivores and posing a conservation threat to endangered species around the world. To get a better panorama of CDV infection in different Orders, a retrospective and documental systematic review of the role of CDV in different non-dog hosts was conducted. The bibliographical data were collected from MedLine/PubMed and Scopus databases. Data related to Order, Family, Genus and Species of the infected animals, the presence or absence of clinical signs, mortality, serological, molecular or antigenic confirmation of CDV infection, geographic location, were collected and summarized.
RESULTS
Two hundred seventeen scientific articles were considered eligible which includes reports of serological evaluation, and antigenic or genomic confirmation of CDV infection in non-dog hosts. CDV infects naturally and experimentally different members of the Orders Carnivora (in 12 Families), Rodentia (four Families), Primates (two Families), Artiodactyla (three Families) and Proboscidea (one Family). The Order Carnivora (excluding domestic dogs) accounts for the vast majority (87.5%) of the records. Clinical disease associated with CDV infection was reported in 51.8% of the records and serological evidence of CDV infection in apparently healthy animals was found in 49.5% of the records. High mortality rate was showed in some of the recorded infections in Orders different to Carnivora. In non-dog hosts, CDV has been reported all continents with the exception of Australasia and in 43 different countries.
CONCLUSIONS
The results of this systematic review demonstrate that CDV is able to infect a very wide range of host species from many different Orders and emphasizes the potential threat of infection for endangered wild species as well as raising concerns about potential zoonotic threats following the cessation of large-scale measles vaccination campaigns in the human population.
Topics: Animals; Animals, Domestic; Distemper; Distemper Virus, Canine; Endangered Species; Humans; Morbillivirus Infections; Zoonoses
PubMed: 27170307
DOI: 10.1186/s12917-016-0702-z