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BMJ (Clinical Research Ed.) Oct 2016To evaluate the effects on non-specific and all cause mortality, in children under 5, of Bacillus Calmette-Guérin (BCG), diphtheria-tetanus-pertussis (DTP), and... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
To evaluate the effects on non-specific and all cause mortality, in children under 5, of Bacillus Calmette-Guérin (BCG), diphtheria-tetanus-pertussis (DTP), and standard titre measles containing vaccines (MCV); to examine internal validity of the studies; and to examine any modifying effects of sex, age, vaccine sequence, and co-administration of vitamin A.
DESIGN
Systematic review, including assessment of risk of bias, and meta-analyses of similar studies.
STUDY ELIGIBILITY CRITERIA
Clinical trials, cohort studies, and case-control studies of the effects on mortality of BCG, whole cell DTP, and standard titre MCV in children under 5.
DATA SOURCES
Searches of Medline, Embase, Global Index Medicus, and the WHO International Clinical Trials Registry Platform, supplemented by contact with experts in the field. To avoid overlap in children studied across the included articles, findings from non-overlapping birth cohorts were identified.
RESULTS
Results from 34 birth cohorts were identified. Most evidence was from observational studies, with some from short term clinical trials. Most studies reported on all cause (rather than non-specific) mortality. Receipt of BCG vaccine was associated with a reduction in all cause mortality: the average relative risks were 0.70 (95% confidence interval 0.49 to 1.01) from five clinical trials and 0.47 (0.32 to 0.69) from nine observational studies at high risk of bias. Receipt of DTP (almost always with oral polio vaccine) was associated with a possible increase in all cause mortality on average (relative risk 1.38, 0.92 to 2.08) from 10 studies at high risk of bias; this effect seemed stronger in girls than in boys. Receipt of standard titre MCV was associated with a reduction in all cause mortality (relative risks 0.74 (0.51 to 1.07) from four clinical trials and 0.51 (0.42 to 0.63) from 18 observational studies at high risk of bias); this effect seemed stronger in girls than in boys. Seven observational studies, assessed as being at high risk of bias, have compared sequences of vaccines; results of a subset of these suggest that administering DTP with or after MCV may be associated with higher mortality than administering it before MCV.
CONCLUSIONS
Evidence suggests that receipt of BCG and MCV reduce overall mortality by more than would be expected through their effects on the diseases they prevent, and receipt of DTP may be associated with an increase in all cause mortality. Although efforts should be made to ensure that all children are immunised on schedule with BCG, DTP, and MCV, randomised trials are needed to compare the effects of different sequences.
Topics: BCG Vaccine; Child; Child, Preschool; Diphtheria; Diphtheria-Tetanus-Pertussis Vaccine; Evidence-Based Medicine; Female; Humans; Immunization Schedule; Infant; Male; Measles; Measles Vaccine; Mortality; Tetanus; Tuberculosis; United Kingdom; Vaccination; Whooping Cough
PubMed: 27737834
DOI: 10.1136/bmj.i5170 -
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 -
Vaccine Oct 2016Important investments were made in countries for the polio eradication initiative. On 25 September 2015, a major milestone was achieved when Nigeria was removed from the... (Review)
Review
BACKGROUND
Important investments were made in countries for the polio eradication initiative. On 25 September 2015, a major milestone was achieved when Nigeria was removed from the list of polio-endemic countries. Routine Immunization, being a key pillar of polio eradication initiative needs to be strengthened to sustain the gains made in countries. For this, there is a huge potential on building on the use of polio infrastructure to contribute to RI strengthening.
METHODS
We reviewed estimates of immunization coverage as reported by the countries to WHO and UNICEF for three vaccines: BCG, DTP3 (third dose of diphtheria-tetanus toxoid- pertussis), and the first dose of measles-containing vaccine (MCV1).We conducted a systematic review of best practices documents from eight countries which had significant polio eradication activities.
RESULTS
Immunization programmes have improved significantly in the African Region. Regional coverage for DTP3 vaccine increased from 51% in 1996 to 77% in 2014. DTP3 coverage increased >3 folds in DRC (18-80%) and Nigeria from 21% to 66%; and >2 folds in Angola (41-87%), Chad (24-46%), and Togo (42-87%). Coverage for BCG and MCV1 increased in all countries. Of the 47 countries in the region, 18 (38%) achieved a national coverage for DTP3 ⩾90% for 2years meeting the Global Vaccine Action (GVAP) target. A decrease was noted in the Ebola-affected countries i.e., Guinea, Liberia and Sierra Leone.
CONCLUSIONS
PEI has been associated with increased spending on immunization and the related improvements, especially in the areas of micro planning, service delivery, program management and capacity building. Continued efforts are needed to mobilize international and domestic support to strengthen and sustain high-quality immunization services in African countries. Strengthening RI will in turn sustain the gains made to eradicate poliovirus in the region.
Topics: Africa; BCG Vaccine; Diphtheria-Tetanus-Pertussis Vaccine; Disease Eradication; Global Health; Humans; Immunization Programs; Measles Vaccine; Nigeria; Poliomyelitis; Poliovirus Vaccine, Oral; Practice Guidelines as Topic; Togo; United Nations; Vaccination Coverage; World Health Organization
PubMed: 27396492
DOI: 10.1016/j.vaccine.2016.05.062 -
The Cochrane Database of Systematic... Jul 2016Immunisation is a powerful public health strategy for improving child survival, not only by directly combating key diseases that kill children but also by providing a... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Immunisation is a powerful public health strategy for improving child survival, not only by directly combating key diseases that kill children but also by providing a platform for other health services. However, each year millions of children worldwide, mostly from low- and middle-income countries (LMICs), do not receive the full series of vaccines on their national routine immunisation schedule. This is an update of the Cochrane review published in 2011 and focuses on interventions for improving childhood immunisation coverage in LMICs.
OBJECTIVES
To evaluate the effectiveness of intervention strategies to boost and sustain high childhood immunisation coverage in LMICs.
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) 2016, Issue 4, part of The Cochrane Library. www.cochranelibrary.com, including the Cochrane Effective Practice and Organisation of Care (EPOC) Group Specialised Register (searched 12 May 2016); MEDLINE In-Process and Other Non-Indexed Citations, MEDLINE Daily and MEDLINE 1946 to Present, OvidSP (searched 12 May 2016); CINAHL 1981 to present, EbscoHost (searched 12 May 2016); Embase 1980 to 2014 Week 34, OvidSP (searched 2 September 2014); LILACS, VHL (searched 2 September 2014); Sociological Abstracts 1952 - current, ProQuest (searched 2 September 2014). We did a citation search for all included studies in Science Citation Index and Social Sciences Citation Index, 1975 to present; Emerging Sources Citation Index 2015 to present, ISI Web of Science (searched 2 July 2016). We also searched the two Trials Registries: ICTRP and ClinicalTrials.gov (searched 5 July 2016) SELECTION CRITERIA: Eligible studies were randomised controlled trials (RCT), non-RCTs, controlled before-after studies, and interrupted time series conducted in LMICs involving children aged from birth to four years, caregivers, and healthcare providers.
DATA COLLECTION AND ANALYSIS
We independently screened the search output, reviewed full texts of potentially eligible articles, assessed risk of bias, and extracted data in duplicate; resolving discrepancies by consensus. We then conducted random-effects meta-analyses and used GRADE to assess the certainty of evidence.
MAIN RESULTS
Fourteen studies (10 cluster RCTs and four individual RCTs) met our inclusion criteria. These were conducted in Georgia (one study), Ghana (one study), Honduras (one study), India (two studies), Mali (one study), Mexico (one study), Nicaragua (one study), Nepal (one study), Pakistan (four studies), and Zimbabwe (one study). One study had an unclear risk of bias, and 13 had high risk of bias. The interventions evaluated in the studies included community-based health education (three studies), facility-based health education (three studies), household incentives (three studies), regular immunisation outreach sessions (one study), home visits (one study), supportive supervision (one study), information campaigns (one study), and integration of immunisation services with intermittent preventive treatment of malaria (one study).We found moderate-certainty evidence that health education at village meetings or at home probably improves coverage with three doses of diphtheria-tetanus-pertussis vaccines (DTP3: risk ratio (RR) 1.68, 95% confidence interval (CI) 1.09 to 2.59). We also found low-certainty evidence that facility-based health education plus redesigned vaccination reminder cards may improve DTP3 coverage (RR 1.50, 95% CI 1.21 to 1.87). Household monetary incentives may have little or no effect on full immunisation coverage (RR 1.05, 95% CI 0.90 to 1.23, low-certainty evidence). Regular immunisation outreach may improve full immunisation coverage (RR 3.09, 95% CI 1.69 to 5.67, low-certainty evidence) which may substantially improve if combined with household incentives (RR 6.66, 95% CI 3.93 to 11.28, low-certainty evidence). Home visits to identify non-vaccinated children and refer them to health clinics may improve uptake of three doses of oral polio vaccine (RR 1.22, 95% CI 1.07 to 1.39, low-certainty evidence). There was low-certainty evidence that integration of immunisation with other services may improve DTP3 coverage (RR 1.92, 95% CI 1.42 to 2.59).
AUTHORS' CONCLUSIONS
Providing parents and other community members with information on immunisation, health education at facilities in combination with redesigned immunisation reminder cards, regular immunisation outreach with and without household incentives, home visits, and integration of immunisation with other services may improve childhood immunisation coverage in LMIC. Most of the evidence was of low certainty, which implies a high likelihood that the true effect of the interventions will be substantially different. There is thus a need for further well-conducted RCTs to assess the effects of interventions for improving childhood immunisation coverage in LMICs.
Topics: Developing Countries; Health Education; Humans; Immunization; Infant; Infant, Newborn; Motivation; Randomized Controlled Trials as Topic; Reward
PubMed: 27394698
DOI: 10.1002/14651858.CD008145.pub3 -
The Cochrane Database of Systematic... Jun 2016More than 7.5 million children younger than age five living in low- and middle-income countries die every year. The World Health Organization (WHO) developed the... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
More than 7.5 million children younger than age five living in low- and middle-income countries die every year. The World Health Organization (WHO) developed the integrated management of childhood illness (IMCI) strategy to reduce mortality and morbidity and to improve quality of care by improving the delivery of a variety of curative and preventive medical and behavioral interventions at health facilities, at home, and in the community.
OBJECTIVES
To evaluate the effects of programs that implement the IMCI strategy in terms of death, nutritional status, quality of care, coverage with IMCI deliverables, and satisfaction of beneficiaries.
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 3), including the Cochrane Effective Practice and Organisation of Care (EPOC) Group Specialised Register; MEDLINE; EMBASE, Ovid; the Cumulative Index to Nursing and Allied Health Literature (CINAHL), EbscoHost; the Latin American Caribbean Health Sciences Literature (LILACS), Virtual Health Library (VHL); the WHO Library & Information Networks for Knowledge Database (WHOLIS); the Science Citation Index and Social Sciences Citation Index, Institute for Scientific Information (ISI) Web of Science; Population Information Online (POPLINE); the WHO International Clinical Trials Registry Platform (WHO ICTRP); and the Global Health, Ovid and Health Management, ProQuest database. We performed searches until 30 June 2015 and supplemented these by searching revised bibliographies and by contacting experts to identify ongoing and unpublished studies.
SELECTION CRITERIA
We sought to include randomised controlled trials (RCTs) and controlled before-after (CBA) studies with at least two intervention and two control sites evaluating the generic IMCI strategy or its adaptation in children younger than age five, and including at minimum efforts to improve health care worker skills for case management. We excluded studies in which IMCI was accompanied by other interventions including conditional cash transfers, food supplementation, and employment. The comparison group received usual health services without provision of IMCI.
DATA COLLECTION AND ANALYSIS
Two review authors independently screened searches, selected trials, and extracted, analysed and tabulated data. We used inverse variance for cluster trials and an intracluster co-efficient of 0.01 when adjustment had not been made in the primary study. We used the GRADE (Grades of Recommendation, Assessment, Development and Evaluation Working Group) approach to assess the certainty of evidence.
MAIN RESULTS
Two cluster-randomised trials (India and Bangladesh) and two controlled before-after studies (Tanzania and India) met our inclusion criteria. Strategies included training of health care staff, management strengthening of health care systems (all four studies), and home visiting (two studies). The two studies from India included care packages targeting the neonatal period.One trial in Bangladesh estimated that child mortality may be 13% lower with IMCI, but the confidence interval (CI) included no effect (risk ratio (RR) 0.87, 95% CI 0.68 to 1.10; 5090 participants; low-certainty evidence). One CBA study in Tanzania gave almost identical estimates (RR 0.87, 95% CI 0.72 to 1.05; 1932 participants).One trial in India examined infant and neonatal mortality by implementing the integrated management of neonatal and childhood illness (IMNCI) strategy including post-natal home visits. Neonatal and infant mortality may be lower in the IMNCI group compared with the control group (infant mortality hazard ratio (HR) 0.85, 95% CI 0.77 to 0.94; neonatal mortality HR 0.91, 95% CI 0.80 to 1.03; one trial, 60,480 participants; low-certainty evidence).We estimated the effect of IMCI on any mortality measured by combining infant and child mortality in the one IMCI and the one IMNCI trial. Mortality may be reduced by IMCI (RR 0.85, 95% CI 0.78 to 0.93; two trials, 65,570 participants; low-certainty evidence).Two trials (India, Bangladesh) evaluated nutritional status and noted that there may be little or no effect on stunting (RR 0.94, 95% CI 0.84 to 1.06; 5242 participants, two trials; low-certainty evidence) and there is probably little or no effect on wasting (RR 1.04, 95% CI 0.87 to 1.25; two trials, 4288 participants; moderate-certainty evidence).The Tanzania CBA study showed similar results.Investigators measured quality of care by observing prescribing for common illnesses at health facilities (727 observations, two studies; very low-certainty evidence) and by observing prescribing by lay health care workers (1051 observations, three studies; very low-certainty evidence). We could not confirm a consistent effect on prescribing at health facilities or by lay health care workers, as certainty of the evidence was very low.For coverage of IMCI deliverables, we examined vaccine and vitamin A coverage, appropriate care seeking, and exclusive breast feeding. Two trials (India, Bangladesh) estimated vaccine coverage for measles and reported that there is probably little or no effect on measles vaccine coverage (RR 0.92, 95% CI 0.80 to 1.05; two trials, 4895 participants; moderate-certainty evidence), with similar effects seen in the Tanzania CBA study. Two studies measured the third dose of diphtheria, pertussis, and tetanus vaccine; and two measured vitamin A coverage, all providing little or no evidence of increased coverage with IMCI.Four studies (2 from India, and 1 each from Tanzania and Bangladesh) reported appropriate care seeking and derived information from careful questioning of mothers about recent illness. Some studies on effects of IMCI may report better care seeking behavior, but others do not report this.All four studies recorded maternal responses on exclusive breast feeding. They provided mixed results and very low-certainty evidence. Therefore, we do not know whether IMCI impacts exclusive breast feeding.No studies reported on the satisfaction of mothers and service users.
AUTHORS' CONCLUSIONS
The mix of interventions examined in research studies evaluating the IMCI strategy varies, and some studies include specific inputs to improve neonatal health. Most studies were conducted in South Asia. Implementing the integrated management of childhood illness strategy may reduce child mortality, and packages that include interventions for the neonatal period may reduce infant mortality. IMCI may have little or no effect on nutritional status and probably has little or no effect on vaccine coverage. Maternal care seeking behavior may be more appropriate with IMCI, but study results have been mixed, providing evidence of very low certainty about whether IMCI has effects on adherence to exclusive breast feeding.
Topics: Bangladesh; Breast Feeding; Child Health Services; Child Mortality; Child, Preschool; Controlled Before-After Studies; Delivery of Health Care, Integrated; Developing Countries; Disease Management; Health Personnel; House Calls; Humans; India; Infant; Infant Mortality; Program Evaluation; Quality Improvement; Randomized Controlled Trials as Topic; Tanzania
PubMed: 27378094
DOI: 10.1002/14651858.CD010123.pub2 -
Value in Health : the Journal of the... 2016Cost-effectiveness analysis of pediatric vaccines for infectious diseases often requires quality-of-life (utility) weights. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Cost-effectiveness analysis of pediatric vaccines for infectious diseases often requires quality-of-life (utility) weights.
OBJECTIVE
To investigate how utility weights have been elicited and used in this context.
METHODS
A systematic review was conducted of studies published between January 1990 and July 2013 that elicited or used utility weights in cost-effectiveness analyses of vaccines for pediatric populations. The review focused on vaccines for 17 infectious diseases and is presented following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology.
RESULTS
A total of 6410 titles and abstracts and 225 full-text articles were reviewed. Of those selected for inclusion (n = 101), 15 articles described the elicitation of utility weights and 86 described economic modeling studies using utilities. Various methods were used to generate utilities, including time trade-off, contingent valuation, and willingness to pay, as well as a preference-based measure with associated value sets, such as the EuroQol five-dimensional questionnaire or the Health Utilities Index. In modeling studies, the source of utilities used was often unclear, poorly reported, or based on weak underlying evidence. We found no articles that reported on the elicitation or use of utilities in diphtheria, polio, or tetanus.
CONCLUSIONS
The scarcity of appropriate utility weights for vaccine-preventable infectious diseases in children and a lack of standardization in their use in economic assessments limit the ability to accurately assess the benefits associated with interventions to prevent infectious diseases. This is an issue that should be of concern to those making decisions regarding the prevention and treatment of infectious childhood illnesses.
Topics: Adolescent; Age Factors; Child; Child, Preschool; Cost-Benefit Analysis; Drug Costs; Female; Health Resources; Health Status; Health Status Indicators; Humans; Immunization Schedule; Infant; Infant, Newborn; Male; Models, Economic; Pediatrics; Quality of Life; Quality-Adjusted Life Years; Risk Assessment; Surveys and Questionnaires; Treatment Outcome; Vaccination; Vaccines
PubMed: 27021761
DOI: 10.1016/j.jval.2015.11.003 -
Vaccine Feb 2016Early onset of persistent otitis media is a priority issue for Australian Indigenous populations. The objective is to determine the direct and short-term impact of one,... (Meta-Analysis)
Meta-Analysis Review
The short-term impact of each primary dose of pneumococcal conjugate vaccine on nasopharyngeal carriage: Systematic review and meta-analyses of randomised controlled trials.
BACKGROUND
Early onset of persistent otitis media is a priority issue for Australian Indigenous populations. The objective is to determine the direct and short-term impact of one, two and three doses of any pneumococcal conjugate vaccine (PCV) formulation on nasopharyngeal (NP) carriage of Streptococcus pneumoniae (Spn) and non-typeable Haemophilus influenzae (NTHi), the otopathogens targeted by current PCVs.
METHODS
We searched MEDLINE (PubMed) and CENTRAL (Cochrane Library) to 29 September 2015. We also scanned reference lists of recent reviews and contacted authors. We included randomised controlled trials (RCTs) with a PCV schedule commencing ≤3 months of age that reported controlled non-cumulative group-specific prevalence data for carriage of Spn or NTHi at age<12 months. We performed a standard risk of bias assessment. We estimated the pooled relative risk (RR) and 95% confidence interval (95%CI) for each vaccine dose on NP carriage by meta-analysis.
RESULTS
We included 16 RCTs involving 14,776 participants. The PCVs were conjugated to diphtheria toxin CRM197, diphtheria toxoid, tetanus toxoid or NTHi protein D and varied in valency (4-13). Controls were non-PCVs, placebo or no vaccine. The earliest carriage outcome was from 2 to 9 months of age. Compared to controls, there were no significant differences between one or two doses of PCV on vaccine-type (VT) pneumococcal carriage at ∼4 and ∼6 months respectively. However, VT carriage was significantly lower at ∼7 months RR 0.67 95%CI 0.56-0.81 from 9 studies and 7613 infants and non-vaccine type (NVT) carriage was higher RR 1.23 95%CI 1.09-1.40 from 8 studies and 5861 infants. No impact on overall pneumococcal or NTHi carriage was found.
CONCLUSIONS
The primary PCV schedule had no significant short-term impact on overall pneumococcal or NTHi NP carriage and a limited impact on VT pneumococcal carriage before the third dose.
Topics: Carrier State; Humans; Infant; Nasopharynx; Pneumococcal Infections; Pneumococcal Vaccines; Randomized Controlled Trials as Topic; Streptococcus pneumoniae; Vaccines, Conjugate
PubMed: 26742947
DOI: 10.1016/j.vaccine.2015.12.048 -
The Cochrane Database of Systematic... Jul 2015Tetanus is an acute, often fatal, disease caused by an exotoxin produced by Clostridium tetani. It occurs in newborn infants born to mothers who do not have sufficient... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Tetanus is an acute, often fatal, disease caused by an exotoxin produced by Clostridium tetani. It occurs in newborn infants born to mothers who do not have sufficient circulating antibodies to protect the infant passively, by transplacental transfer. Prevention may be possible by the vaccination of pregnant or non-pregnant women, or both, with tetanus toxoid, and the provision of clean delivery services. Tetanus toxoid consists of a formaldehyde-treated toxin that stimulates the production of antitoxin.
OBJECTIVES
To assess the effectiveness of tetanus toxoid, administered to women of reproductive age or pregnant women, to prevent cases of, and deaths from, neonatal tetanus.
SEARCH METHODS
We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 January 2015), CENTRAL (The Cochrane Library 2015, Issue 1), PubMed (1966 to 28 January 2015), EMBASE (1974 to 28 January 2015) and reference lists of retrieved studies.
SELECTION CRITERIA
Randomised or quasi-randomised trials evaluating the effects of tetanus toxoid in pregnant women or women of reproductive age on numbers of neonatal tetanus cases and deaths.
DATA COLLECTION AND ANALYSIS
Two review authors independently assessed trials for inclusion and risk of bias, extracted data and checked them for accuracy.
MAIN RESULTS
Two effectiveness trials (9823 infants) and one safety trial (48 mothers) were included. The main outcomes were measured on infants born to a subset of those randomised women who became pregnant during the course of the studies. For our primary outcomes, there was no high-quality evidence according to GRADE assessments.One study (1182 infants) assessed the effectiveness of tetanus toxoid in comparison with influenza vaccine in preventing neonatal tetanus deaths. A single dose did not provide significant protection against neonatal tetanus deaths, (risk ratio (RR) 0.57, 95% confidence interval (CI) 0.26 to 1.24; 494 infants; GRADE: low-quality evidence). However, a two- or three-dose course did provide protection against neonatal deaths, (RR 0.02, 95% CI 0.00 to 0.30; 688 infants; GRADE: moderate-quality evidence). Administration of a two- or three-dose course resulted in significant protection when all causes of death are considered as an outcome (RR 0.31, 95% CI 0.17 to 0.55; 688 infants; GRADE: moderate-quality evidence). No effect was detected on causes of death other than tetanus. Cases of neonatal tetanus after at least one dose of tetanus toxoid were reduced in the tetanus toxoid group, (RR 0.20, 95% CI 0.10 to 0.40; 1182 infants; GRADE: moderate-quality evidence).Another study, involving 8641 children, assessed the effectiveness of tetanus-diphtheria toxoid in comparison with cholera toxoid in preventing neonatal mortality after one or two doses. Neonatal mortality was reduced in the tetanus-diphtheria toxoid group (RR 0.68, 95% CI 0.56 to 0.82). In preventing deaths at four to 14 days, neonatal mortality was reduced again in the tetanus-diphtheria toxoid group (RR 0.38, 95% CI 0.27 to 0.55). The quality of evidence as assessed using GRADE was found to be low.The third small trial assessed that pain at injection site was reported more frequently among pregnant women who received tetanus diphtheria acellular pertussis than placebo (RR 5.68, 95% CI 1.54 to 20.94; GRADE: moderate-quality evidence).
AUTHORS' CONCLUSIONS
Available evidence supports the implementation of immunisation practices on women of reproductive age or pregnant women in communities with similar, or higher, levels of risk of neonatal tetanus, to the two study sites.
Topics: Adult; Cause of Death; Diphtheria-Tetanus Vaccine; Female; Humans; Infant, Newborn; Influenza Vaccines; Pregnancy; Randomized Controlled Trials as Topic; Tetanus; Tetanus Toxoid
PubMed: 26144877
DOI: 10.1002/14651858.CD002959.pub4 -
Vaccine Aug 2015The purpose of this systematic review is to identify, describe and assess the potential effectiveness of strategies to respond to issues of vaccine hesitancy that have... (Review)
Review
UNLABELLED
The purpose of this systematic review is to identify, describe and assess the potential effectiveness of strategies to respond to issues of vaccine hesitancy that have been implemented and evaluated across diverse global contexts.
METHODS
A systematic review of peer reviewed (January 2007-October 2013) and grey literature (up to October 2013) was conducted using a broad search strategy, built to capture multiple dimensions of public trust, confidence and hesitancy concerning vaccines. This search strategy was applied and adapted across several databases and organizational websites. Descriptive analyses were undertaken for 166 (peer reviewed) and 15 (grey literature) evaluation studies. In addition, the quality of evidence relating to a series of PICO (population, intervention, comparison/control, outcomes) questions defined by the SAGE Working Group on Vaccine Hesitancy (WG) was assessed using Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria; data were analyzed using Review Manager.
RESULTS
Across the literature, few strategies to address vaccine hesitancy were found to have been evaluated for impact on either vaccination uptake and/or changes in knowledge, awareness or attitude (only 14% of peer reviewed and 25% of grey literature). The majority of evaluation studies were based in the Americas and primarily focused on influenza, human papillomavirus (HPV) and childhood vaccines. In low- and middle-income regions, the focus was on diphtheria, tetanus and pertussis, and polio. Across all regions, most interventions were multi-component and the majority of strategies focused on raising knowledge and awareness. Thirteen relevant studies were used for the GRADE assessment that indicated evidence of moderate quality for the use of social mobilization, mass media, communication tool-based training for health-care workers, non-financial incentives and reminder/recall-based interventions. Overall, our results showed that multicomponent and dialogue-based interventions were most effective. However, given the complexity of vaccine hesitancy and the limited evidence available on how it can be addressed, identified strategies should be carefully tailored according to the target population, their reasons for hesitancy, and the specific context.
Topics: Communication; Health Knowledge, Attitudes, Practice; Health Personnel; Humans; Patient Acceptance of Health Care; Patient Compliance; Treatment Refusal; Vaccination; Vaccines; World Health Organization
PubMed: 25896377
DOI: 10.1016/j.vaccine.2015.04.040 -
The Cochrane Database of Systematic... Sep 2014Routine use of whole-cell pertussis (wP) vaccines was suspended in some countries in the 1970s and 1980s because of concerns about adverse effects. Following this... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Routine use of whole-cell pertussis (wP) vaccines was suspended in some countries in the 1970s and 1980s because of concerns about adverse effects. Following this action, there was a resurgence of whooping cough. Acellular pertussis (aP) vaccines, containing purified or recombinant Bordetella pertussis (B. pertussis) antigens, were developed in the hope that they would be as effective, but less reactogenic than the whole-cell vaccines. This is an update of a Cochrane review first published in 1999, and previously updated in 2012. In this update, we included no new studies.
OBJECTIVES
To assess the efficacy and safety of acellular pertussis vaccines in children and to compare them with the whole-cell vaccines.
SEARCH METHODS
We searched CENTRAL (2013, Issue 12), MEDLINE (1950 to January week 2, 2014), EMBASE (1974 to January 2014), Biosis Previews (2009 to January 2014) and CINAHL (2009 to January 2014).
SELECTION CRITERIA
We selected double-blind randomised efficacy and safety trials of aP vaccines in children up to six years old, with active follow-up of participants and laboratory verification of pertussis cases.
DATA COLLECTION AND ANALYSIS
Two review authors independently extracted data and assessed the risk of bias in the studies. Differences in trial design precluded a meta-analysis of the efficacy data. We pooled the safety data from individual trials using a random-effects meta-analysis model.
MAIN RESULTS
We included six efficacy trials with a total of 46,283 participants and 52 safety trials with a total of 136,541 participants. Most of the safety trials did not report the methods for random sequence generation, allocation concealment and blinding, which made it difficult to assess the risk of bias in the studies. The efficacy of multi-component (≥ three) vaccines varied from 84% to 85% in preventing typical whooping cough (characterised by 21 or more consecutive days of paroxysmal cough with confirmation of B. pertussis infection by culture, appropriate serology or contact with a household member who has culture-confirmed pertussis), and from 71% to 78% in preventing mild pertussis disease (characterised by seven or more consecutive days of cough with confirmation of B. pertussis infection by culture or appropriate serology). In contrast, the efficacy of one- and two-component vaccines varied from 59% to 78% against typical whooping cough and from 41% to 58% against mild pertussis disease. Multi-component acellular vaccines are more effective than low-efficacy whole-cell vaccines, but may be less effective than the highest-efficacy whole-cell vaccines. Most systemic and local adverse events were significantly less common with aP vaccines than with wP vaccines for the primary series as well as for the booster dose.
AUTHORS' CONCLUSIONS
Multi-component (≥ three) aP vaccines are effective in preventing whooping cough in children. Multi-component aP vaccines have higher efficacy than low-efficacy wP vaccines, but they may be less efficacious than the highest-efficacy wP vaccines. Acellular vaccines have fewer adverse effects than whole-cell vaccines for the primary series as well as for booster doses.
Topics: Age Factors; Child; Child, Preschool; Diphtheria-Tetanus-Pertussis Vaccine; Diphtheria-Tetanus-acellular Pertussis Vaccines; Humans; Infant; Pertussis Vaccine; Randomized Controlled Trials as Topic; Whooping Cough
PubMed: 25228233
DOI: 10.1002/14651858.CD001478.pub6