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Vaccine Oct 2017The risk of post-vaccination adverse events (AEs) is a primary public health concern. Among the AEs, pain is a significant source of anxiety for both children and their... (Review)
Review
PURPOSE
The risk of post-vaccination adverse events (AEs) is a primary public health concern. Among the AEs, pain is a significant source of anxiety for both children and their parents. This review describes and assesses the intensity of pain experienced by children post-vaccination with widely used Measles-Mumps-Rubella (MMR) vaccines.
METHODS
A systematic literature search was conducted in Pubmed, Embase and Cochrane to identify publications describing immediate pain at injection site (primary objective) or pain within days (secondary objective) after 2 specific MMR vaccines. Immediate pain ('acute pain' according to the Brighton Collaboration case definition) was defined as pain occurring at the time or within 5min of injection.
RESULTS
Four studies, which compared the intensity of immediate injection site pain experienced by children after MMR vaccination, were identified. Various pain assessment tools and methods were used to quantify the intensity of pain, including the median difference in Visual Analog Scale scores between vaccine groups. All four studies showed significantly less immediate pain caused by Priorix (GSK Vaccines) compared with M-M-R II (Merck & Co., Inc.).
CONCLUSIONS
To our knowledge, this review summarizes for the first time the available scientific evidence on the intensity of pain following different MMR vaccines. It highlights that MMR vaccines can differ in terms of immediate pain. Further research may be needed to better understand the underlying reason for this observation. In this context, it is very important to understand which physicochemical properties are most relevant for the immediate pain profile of a vaccine to thereby support the development of vaccines with the best possible immediate pain profile.
Topics: Humans; Measles-Mumps-Rubella Vaccine; Pain; Vaccination; Vaccines, Combined
PubMed: 28893478
DOI: 10.1016/j.vaccine.2017.08.068 -
BMC Infectious Diseases Sep 2017Individual-based models (IBMs) are useful to simulate events subject to stochasticity and/or heterogeneity, and have become well established to model the potential... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Individual-based models (IBMs) are useful to simulate events subject to stochasticity and/or heterogeneity, and have become well established to model the potential (re)emergence of pathogens (e.g., pandemic influenza, bioterrorism). Individual heterogeneity at the host and pathogen level is increasingly documented to influence transmission of endemic diseases and it is well understood that the final stages of elimination strategies for vaccine-preventable childhood diseases (e.g., polio, measles) are subject to stochasticity. Even so it appears IBMs for both these phenomena are not well established. We review a decade of IBM publications aiming to obtain insights in their advantages, pitfalls and rationale for use and to make recommendations facilitating knowledge transfer within and across disciplines.
METHODS
We systematically identified publications in Web of Science and PubMed from 2006-2015 based on title/abstract/keywords screening (and full-text if necessary) to retrieve topics, modeling purposes and general specifications. We extracted detailed modeling features from papers on established vaccine-preventable childhood diseases based on full-text screening.
RESULTS
We identified 698 papers, which applied an IBM for infectious disease transmission, and listed these in a reference database, describing their general characteristics. The diversity of disease-topics and overall publication frequency have increased over time (38 to 115 annual publications from 2006 to 2015). The inclusion of intervention strategies (8 to 52) and economic consequences (1 to 20) are increasing, to the detriment of purely theoretical explorations. Unfortunately, terminology used to describe IBMs is inconsistent and ambiguous. We retrieved 24 studies on a vaccine-preventable childhood disease (covering 7 different diseases), with publication frequency increasing from the first such study published in 2008. IBMs have been useful to explore heterogeneous between- and within-host interactions, but combined applications are still sparse. The amount of missing information on model characteristics and study design is remarkable.
CONCLUSIONS
IBMs are suited to combine heterogeneous within- and between-host interactions, which offers many opportunities, especially to analyze targeted interventions for endemic infections. We advocate the exchange of (open-source) platforms and stress the need for consistent "branding". Using (existing) conventions and reporting protocols would stimulate cross-fertilization between research groups and fields, and ultimately policy making in decades to come.
Topics: Disease Transmission, Infectious; Epidemics; Humans; Models, Theoretical; Terminology as Topic; Vaccines
PubMed: 28893198
DOI: 10.1186/s12879-017-2699-8 -
The Cochrane Database of Systematic... Jun 2017Measles is an important cause of childhood morbidity and mortality globally, despite increasing vaccine coverage. Zinc plays a significant role in the maintenance of... (Review)
Review
BACKGROUND
Measles is an important cause of childhood morbidity and mortality globally, despite increasing vaccine coverage. Zinc plays a significant role in the maintenance of normal immunological functions, therefore supplements given to zinc-deficient children will increase the availability of zinc and could reduce measles-related morbidity and mortality. This is an update of a review first published in 2015.
OBJECTIVES
To assess the effects of zinc supplementation in reducing morbidity and mortality in children with measles.
SEARCH METHODS
We searched CENTRAL (03 February 2017, Issue 2), MEDLINE (1946 to 03 February 2017), Embase (1974 to 03 February 2017), CINAHL (1981 to 03 February 2017), LILACS (1982 to 03 February 2017), Web of Science (1985 to 03 February 2017), and BIOSIS Previews (1985 to 27 June 2014). We also searched ClinicalTrials.gov, the Australian New Zealand Clinical Trials Registry and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) on 03 February 2017 to identify unpublished and ongoing studies.
SELECTION CRITERIA
Randomised controlled trials (RCTs) and quasi-RCTs evaluating the effects of zinc in reducing morbidity and mortality in children with measles.
DATA COLLECTION AND ANALYSIS
Two review authors independently assessed the studies for inclusion and extracted data on outcomes, details of the interventions, and other study characteristics using a standardised data extraction form. We used risk ratio (RR) and hazard ratio (HR) as measures of effect with 95% confidence intervals (CI). We included only one study, and did not conduct meta-analysis.
MAIN RESULTS
We did not identify any new studies for inclusion in this update. One RCT met our inclusion criteria. The study was conducted in India and included 85 children diagnosed with measles and pneumonia. The trial showed no significant difference in mortality between children with measles and pneumonia who received zinc supplements and those who received placebo (RR 0.34, 95% CI 0.01 to 8.14). There was no significant difference in time to absence of fever between children who received zinc supplements and those who did not (HR 1.08, 95% CI 0.67 to 1.74). No treatment-related side effects were reported in either group. We assessed the overall quality of the evidence as very low.
AUTHORS' CONCLUSIONS
We could not draw any definitive conclusions from this review about the effects of zinc supplementation on clinical outcomes of children with measles due to the very low quality of the evidence available. There is insufficient evidence to confirm or refute the effect of zinc supplementation in children with measles.
Topics: Child; Fever; Humans; Measles; Pneumonia; Randomized Controlled Trials as Topic; Zinc
PubMed: 28631310
DOI: 10.1002/14651858.CD011177.pub3 -
The Cochrane Database of Systematic... Feb 2017Childhood vaccination is an effective way to prevent serious childhood illnesses, but many children do not receive all the recommended vaccines. There are various... (Review)
Review
BACKGROUND
Childhood vaccination is an effective way to prevent serious childhood illnesses, but many children do not receive all the recommended vaccines. There are various reasons for this; some parents lack access because of poor quality health services, long distances or lack of money. Other parents may not trust vaccines or the healthcare workers who provide them, or they may not see the need for vaccination due to a lack of information or misinformation about how vaccinations work and the diseases they can prevent.Communication with parents about childhood vaccinations is one way of addressing these issues. Communication can take place at healthcare facilities, at home or in the community. Communication can be two-way, for example face-to-face discussions between parents and healthcare providers, or one-way, for instance via text messages, posters or radio programmes. Some types of communication enable parents to actively discuss vaccines and their benefits and harms, as well as diseases they can prevent. Other communication types simply give information about vaccination issues or when and where vaccines are available. People involved in vaccine programmes need to understand how parents experience different types of communication about vaccination and how this influences their decision to vaccinate.
OBJECTIVES
The specific objectives of the review were to identify, appraise and synthesise qualitative studies exploring: parents' and informal caregivers' views and experiences regarding communication about childhood vaccinations and the manner in which it is communicated; and the influence that vaccination communication has on parents' and informal caregivers' decisions regarding childhood vaccination.
SEARCH METHODS
We searched MEDLINE (OvidSP), MEDLINE In-process and Other Non-Index Citations (Ovid SP), Embase (Ovid), CINAHL (EbscoHOST), and Anthropology Plus (EbscoHost) databases for eligible studies from inception to 30 August 2016. We developed search strategies for each database, using guidelines developed by the Cochrane Qualitative Research Methods Group for searching for qualitative evidence as well as modified versions of the search developed for three related reviews of effectiveness. There were no date or geographic restrictions for the search.
SELECTION CRITERIA
We included studies that utilised qualitative methods for data collection and analysis; focused on the views and experiences of parents and informal caregivers regarding information about vaccination for children aged up to six years; and were from any setting globally where information about childhood vaccinations was communicated or distributed.
DATA COLLECTION AND ANALYSIS
We used maximum variation purposive sampling for data synthesis, using a three-step sampling frame. We conducted a thematic analysis using a constant comparison strategy for data extraction and synthesis. We assessed our confidence in the findings using the GRADE-CERQual approach. High confidence suggests that it is highly likely that the review finding is a reasonable representation of the phenomenon of interest, while very low confidence indicates that it is not clear whether the review finding is a reasonable representation of it. Using a matrix model, we then integrated our findings with those from other Cochrane reviews that assessed the effects of different communication strategies on parents' knowledge, attitudes and behaviour about childhood vaccination.
MAIN RESULTS
We included 38 studies, mostly from high-income countries, many of which explored mothers' perceptions of vaccine communication. Some focused on the MMR (measles, mumps, rubella) vaccine.In general, parents wanted more information than they were getting (high confidence in the evidence). Lack of information led to worry and regret about vaccination decisions among some parents (moderate confidence).Parents wanted balanced information about vaccination benefits and harms (high confidence), presented clearly and simply (moderate confidence) and tailored to their situation (low confidence in the evidence). Parents wanted vaccination information to be available at a wider variety of locations, including outside health services (low confidence) and in good time before each vaccination appointment (moderate confidence).Parents viewed health workers as an important source of information and had specific expectations of their interactions with them (high confidence). Poor communication and negative relationships with health workers sometimes impacted on vaccination decisions (moderate confidence).Parents generally found it difficult to know which vaccination information source to trust and challenging to find information they felt was unbiased and balanced (high confidence).The amount of information parents wanted and the sources they felt could be trusted appeared to be linked to acceptance of vaccination, with parents who were more hesitant wanting more information (low to moderate confidence).Our synthesis and comparison of the qualitative evidence shows that most of the trial interventions addressed at least one or two key aspects of communication, including the provision of information prior to the vaccination appointment and tailoring information to parents' needs. None of the interventions appeared to respond to negative media stories or address parental perceptions of health worker motives.
AUTHORS' CONCLUSIONS
We have high or moderate confidence in the evidence contributing to several review findings. Further research, especially in rural and low- to middle-income country settings, could strengthen evidence for the findings where we had low or very low confidence. Planners should consider the timing for making vaccination information available to parents, the settings where information is available, the provision of impartial and clear information tailored to parental needs, and parents' perceptions of health workers and the information provided.
Topics: Caregivers; Child; Communication; Decision Making; Health Knowledge, Attitudes, Practice; Humans; Parents; Qualitative Research; Trust; Vaccination
PubMed: 28169420
DOI: 10.1002/14651858.CD011787.pub2 -
Pathogens and Global Health Mar 2017The decline of immunization rates in countries of origin of migrants and refugees, along with risky conditions during the journey to Europe, may threaten migrants'... (Review)
Review
The decline of immunization rates in countries of origin of migrants and refugees, along with risky conditions during the journey to Europe, may threaten migrants' health. We performed a systematic review of the scientific literature in order to assess the frequency of vaccine preventable diseases, and vaccination coverage among migrants and refugees in Europe. To this end, Medline and Cochrane databases were considered. After the screening and the selection process, 58 papers were included in the review. We focused on the following vaccine-preventable diseases: hepatitis B, measles, rubella, mumps, tetanus, poliomyelitis, pertussis, diphtheria, meningitis, and varicella. The results were presented as a qualitative synthesis. In summary, several studies highlighted that migrants and refugees have lower immunization rates compared to European-born individuals. Firstly, this is due to low vaccination coverage in the country of origin. Then, several problems may limit migrants' access to vaccination in Europe: (i) migrants are used to move around the continent, and many vaccines require multiple doses at regular times; (ii) information on the immunization status of migrants is often lacking; (iii) hosting countries face severe economic crises; (iv) migrants often refuse registration with medical authorities for fear of legal consequences and (v) the lack of coordination among public health authorities of neighboring countries may determine either duplications or lack of vaccine administration. Possible strategies to overcome these problems include tailoring immunization services on the specific needs of the target population, developing strong communication campaigns, developing vaccination registers, and promoting collaboration among public health authorities of European Countries.
Topics: Communicable Disease Control; Communicable Diseases; Europe; Evidence-Based Medicine; Humans; Refugees; Transients and Migrants; Vaccination
PubMed: 28165878
DOI: 10.1080/20477724.2017.1281374 -
Vaccine Mar 2017Live vaccines are generally contraindicated on immunosuppressive therapy due to safety concerns. However, data are limited to corroborate this practice. (Review)
Review
Safety of live vaccinations on immunosuppressive therapy in patients with immune-mediated inflammatory diseases, solid organ transplantation or after bone-marrow transplantation - A systematic review of randomized trials, observational studies and case reports.
BACKGROUND
Live vaccines are generally contraindicated on immunosuppressive therapy due to safety concerns. However, data are limited to corroborate this practice.
OBJECTIVES
To estimate the safety of live vaccinations in patients with immune-mediated inflammatory diseases (IMID) or solid organ transplantation (SOT) on immunosuppressive treatment and in patients after bone-marrow transplantation (BMT).
DATA SOURCES
A search was conducted in electronic databases (Cochrane, Pubmed, Embase) and additional literature was identified by targeted searches.
ELIGIBILITY CRITERIA
Randomized trials, observational studies and case reports.
POPULATION
Patients with IMID or SOT on immunosuppressive treatment and BMT patients <2years after transplantation.
INTERVENTION/VACCINATIONS LOOKED AT
Live vaccinations: mumps, measles, rubella (MMR), yellow fever (YF), varicella vaccine (VV), herpes zoster (HZ), oral typhoid, oral polio, rotavirus, Bacillus Calmette-Guérin (BCG), smallpox.
DATA EXTRACTION
One author performed the data extraction using predefined data fields. It was cross-checked by two other authors.
RESULTS
7305 articles were identified and 64 articles were included: 40 on IMID, 16 on SOT and 8 on BMT patients. In most studies, the administration of live vaccines was safe. However, some serious vaccine-related adverse events occurred. 32 participants developed an infection with the vaccine strain; in most cases the infection was mild. However, in two patients fatal infections were reported: a patient with RA/SLE overlap who started MTX/dexamethasone treatment four days after the YFV developed a yellow fever vaccine-associated viscerotropic disease (YEL-AVD) and died. The particular vaccine lot was found to be associated with a more than 20 times risk of YEL-AVD. One infant whose mother was under infliximab treatment during pregnancy received the BCG vaccine at the age of three months and developed disseminated BCG infection and died. An immunogenicity assessment was performed in 43 studies. In most cases the patients developed satisfactory seroprotection rates. In the IMID group, YFV and VV demonstrated high seroconversion rates. MTX and tumor necrosis factor inhibitory therapy appeared to reduce immune responses to VV and HZ vaccine, but not to MMR and YF-revaccination. Seroconversion in SOT and BMT patients showed mostly higher rates for rubella than for measles, mumps and varicella.
LIMITATIONS
Risk of bias was high in the majority of studies since 39 of them were observational and 17 were case series/case reports. Only eight studies were randomized trials. BMT patient numbers included in this review were low.
CONCLUSIONS
Although live vaccinations were safe and sufficiently immunogenic in most studies, some serious reactions and vaccine-related infections were reported in immunosuppressed IMID and SOT patients. Apart from mild vaccine-related infections MMR and VV vaccines were safe when administered less than two years after BMT.
IMPLICATIONS OF KEY FINDINGS
Until further data are available, live vaccinations under most immunosuppressive treatments should only be administered after a careful risk benefit assessment of medications and dosages.
FUNDING
None.
Topics: Bone Marrow Transplantation; Chickenpox; Chickenpox Vaccine; Female; Humans; Immune System Diseases; Immunosuppressive Agents; Infant; Inflammation; Male; Measles; Measles-Mumps-Rubella Vaccine; Mumps; Observational Studies as Topic; Organ Transplantation; Pregnancy; Randomized Controlled Trials as Topic; Rubella; Vaccination; Vaccines, Attenuated; Vaccines, Combined; Yellow Fever; Yellow Fever Vaccine
PubMed: 28162821
DOI: 10.1016/j.vaccine.2017.01.048 -
Annali Di Igiene : Medicina Preventiva... 2017Despite substantial progress towards measles and rubella control, outbreaks continue to threaten elimination goals worldwide. (Review)
Review
BACKGROUND
Despite substantial progress towards measles and rubella control, outbreaks continue to threaten elimination goals worldwide.
STUDY DESIGN
This paper aims to document progress towards the global eradication of measles and rubella. In particular, it investigates the major challenges faced by Italy in reaching the elimination goals.
METHODS
A review of the most important literature was carried out. Furthermore, a systematic review of the scientific literature on measles and rubella in the Italian setting was performed for the period 2000-2016.
RESULTS
In the National Plan 2010-2015, Italy renewed its commitment to eliminate measles and rubella by 2015. However, Italy recently experienced a high measles burden (2,205 cases in 2013, 1,694 in 2014). Between June 2015 and May 2016, 515 cases were reported, accounting for 28% all cases in Europe. Immunization coverage decreased in recent years, with no Region reaching the 95% target. The systematic review included a total of 175 papers, with an upward trend in the number of published articles, which demonstrates an increasing interest in the field of measles and rubella. The review highlights the need to improve the commitment of the Italian Regions to the elimination goals; to promote Supplementary Immunization Activities (SIAs); to improve the communication skills of health care workers; to improve the health literacy of citizens; and to enhance integrated measles and rubella surveillance.
CONCLUSION
Elimination of measles and rubella in Italy will require a substantial improvement in both commitment of the 21 Regions and activity of the whole country towards the WHO goals.
Topics: Disease Eradication; Disease Outbreaks; Europe; Female; Health Policy; Humans; Italy; Measles; Measles Vaccine; Rubella; Rubella Syndrome, Congenital; Rubella Vaccine; Vaccination; World Health Organization
PubMed: 28067934
DOI: 10.7416/ai.2017.2128 -
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 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