Role of endothelial PDGFB in arterio-venous malformations pathogenesis

Arterial-venous malformations (AVMs) are direct connections between arteries and veins without an intervening capillary bed. Either familial inherited or sporadically occurring, localized pericytes (PCs) drop is among the AVMs' hallmarks. Whether impaired PC coverage triggers AVMs or it is a secondary event is unclear. Here we evaluated the role of the master regulator of PC recruitment, Platelet derived growth factor B (PDGFB) in AVM pathogenesis. Using tamoxifen-inducible deletion of Pdgfb in endothelial cells (ECs), we show that disruption of EC Pdgfb-mediated PC recruitment and maintenance leads to capillary enlargement and organotypic AVM-like structures. These vascular lesions contain non-proliferative hyperplastic, hypertrophic and miss-oriented capillary ECs with an altered capillary EC fate identity. Mechanistically, we propose that PDGFB maintains capillary EC size and caliber to limit hemodynamic changes, thus restricting expression of Krüppel like factor 4 and activation of Bone morphogenic protein, Transforming growth factor β and NOTCH signaling in ECs. Furthermore, our study emphasizes that inducing or activating PDGFB signaling may be a viable therapeutic approach for treating vascular malformations.

Measurement of energy and directional distribution of neutron ambient dose equivalent for the 7Li(p,n)7Be reaction

Double differential neutron fluence distributions were measured in the 7Li(p,n)7Be reaction for proton beam energies 7, 9 and 12 MeV. Seven liquid scintillator based detectors were employed to measure neutron fluence distributions using the Time of Flight technique. Neutron ambient dose equivalents were determined from the measured fluence distribution using ICRP (International Commission on Radiological Protection) recommended fluence to dose equivalent conversion coefficients. Neutron dose equivalents were also measured using a conventional BF3 detector based REM counter. Ambient dose equivalent measured by the REM counter is found to be in agreement with that determined from the neutron fluence spectra within their uncertainties. Angular distributions of the ambient dose equivalents were also determined from the measured fluence distributions at different angles.

Tissue factor binds to and inhibits interferon-α receptor 1 signaling

Tissue factor (TF), which is a member of the cytokine receptor family, promotes coagulation and coagulation-dependent inflammation. TF also exerts protective effects through unknown mechanisms. Here, we showed that TF bound to interferon-α receptor 1 (IFNAR1) and antagonized its signaling, preventing spontaneous sterile inflammation and maintaining immune homeostasis. Structural modeling and direct binding studies revealed binding of the TF C-terminal fibronectin III domain to IFNAR1, which restricted the expression of interferon-stimulated genes (ISGs). Podocyte-specific loss of TF in mice (PodΔF3) resulted in sterile renal inflammation, characterized by JAK/STAT signaling, proinflammatory cytokine expression, disrupted immune homeostasis, and glomerulopathy. Inhibiting IFNAR1 signaling or loss of Ifnar1 expression in podocytes attenuated these effects in PodΔF3 mice. As a heteromer, TF and IFNAR1 were both inactive, while dissociation of the TF-IFNAR1 heteromer promoted TF activity and IFNAR1 signaling. These data suggest that the TF-IFNAR1 heteromer is a molecular switch that controls thrombo-inflammation.

SMAD4 maintains the fluid shear stress set point to protect against arterial-venous malformations

Vascular networks form, remodel, and mature under the influence of both fluid shear stress (FSS) and soluble factors. Physiological FSS promotes and maintains vascular stability via synergy with bone morphogenic proteins 9 and 10 (BMP9 and BMP10). Conversely, mutation of the BMP receptors activin-like kinase 1 (ALK1), endoglin (ENG), or the downstream effector, SMAD family member 4 (SMAD4) leads to hereditary hemorrhagic telangiectasia (HHT), characterized by fragile and leaky arterial-venous malformations (AVMs). How endothelial cells (ECs) integrate FSS and BMP signals in vascular development and homeostasis and how mutations give rise to vascular malformations is not well understood. Here, we aimed to elucidate the mechanism of synergy between FSS and SMAD signaling in vascular stability and how disruption of this synergy leads to AVMs. We found that loss of Smad4 increased the sensitivity of ECs to flow by lowering the FSS set point, with resulting AVMs exhibiting features of excessive flow-mediated morphological responses. Mechanistically, loss of SMAD4 disinhibits flow-mediated KLF4-TIE2-PI3K/Akt signaling, leading to cell cycle progression-mediated loss of arterial identity due to KLF4-mediated repression of cyclin dependent Kinase (CDK) inhibitors CDKN2A and CDKN2B. Thus, AVMs caused by Smad4 deletion are characterized by chronic high flow remodeling with excessive EC proliferation and loss of arterial identity as triggering events.

Early arrivals: association of maternal obstetric factors with preterm births and their survival in India

OBJECTIVES

Preterm birth (PTB) increases the risk of various acute and chronic morbidities and premature mortality in children under 5 years of age. The present study examines the association between different maternal obstetric factors and PTB. In addition, this study estimates the risk of neonatal mortality among children born preterm.

STUDY DESIGN

Retrospective two-stage stratified sample design.

METHODS

The weighted prevalence of PTB was estimated using data on 148,746 most recent institutional births from the National Family Health Survey (NFHS)-4, 2015-16. The Poisson regression model was used to investigate the association between maternal obstetric factors and PTB. Using Cox's proportional hazard model, the risk of neonatal mortality among PTBs was estimated.

RESULTS

Maternal obstetric factors, such as minimal antenatal care, delivery complications, history of previous caesarean delivery and delivery at private health facilities, were significantly associated with an increased risk of PTB. The survival probability of preterm babies sharply declined in the first week of life and thereafter was found to stabilise. The risk of mortality in the first 28 days of life increased 2.5-fold if the baby was born preterm. Optimising antenatal care was found to lower the likelihood of PTB and improve their chances of survival.

CONCLUSION

Antenatal care services and delivery care practices in private facilities were strongly associated with the incidence and survival of PTB. Evaluating associations of history of caesarean births on future pregnancies can help understand their deleterious effects on PTB. Affordable, accessible and available antenatal care services, in both public and private facilities, can increase the survival rates of PTBs.

P–391 Role of subcutaneous granulocyte colony-stimulating factor infusion in thin endometrium

Study question

To assess the role of subcutaneous granulocyte colony-stimulating factor (G-CSF) in thin endometrium cases.

Summary answer

G CSF has beneficial role to improve the endometrium thickness in thin endometrium.

What is known already

Endometrium is very important for embryo implantation and the endometrial thickness is the marker of receptivity of the endometrium.

Study design, size, duration

Study design - Retrospective analysis

Size - 88 infertile females with thin endometrium (< 7 mm) in the age group of 23 to 40 years Duration - one year.

Participants/materials, setting, methods

In the group 1 of 44 females, subcutaneous infusion of G CSF (300 mcg/ml) was added along with other supplements and if lining was not more than 7 mm in 72 hours, then second infusion was given. In the group 2 of 44 females, only estradiol valerate and sildenafil were given.The efficacy of G CSF was evaluated by assessing the endometrium thickness before embryo transfer, pregnancy rates and clinical pregnancy rates.

Main results and the role of chance

There was no difference between the two groups regarding demographic variables, egg reserve, sperm parameters, number of embryos transferred and embryo quality. . The pregnancy rate was 60% (24 out of 40 cases) in the group 1 that was significantly higher than in-group 2 that was 31% (9 out of 29 cases) with p value < 0.0001. The clinical pregnancy rate was also significantly higher in-group 1 (55%) as compared to group 2 (24%) with p value < 0.0001.

Limitations, reasons for caution

Further larger cohort studies are required to explore the subcutaneous role of G CSF in thin endometrium.

Wider implications of the findings: Granulocyte colony-stimulating factor has beneficial role to improve the endometrium thickness in thin endometrium. In most of previous studies, the intrauterine infusion of G CSF was given to improve the uterine lining. This is one of the few studies done that showed subcutaneous role of G CSF in thin endometrium.

Trial registration number

Not applicable

Pro-poor policies and improvements in maternal health outcomes in India

BACKGROUND

Since 2005, India has experienced an impressive 77% reduction in maternal mortality compared to the global average of 43%. What explains this impressive performance in terms of reduction in maternal mortality and improvement in maternal health outcomes? This paper evaluates the effect of household wealth status on maternal mortality in India, and also separates out the performance of the Empowered Action Group (EAG) states and the Southern states of India. The results are discussed in the light of various pro-poor programmes and policies designed to reduce maternal mortality and the existing supply side gaps in the healthcare system of India. Using multiple sources of data, this study aims to understand the trends in maternal mortality (1997-2017) between EAG and non EAG states in India and explore various household, economic and policy factors that may explain reduction in maternal mortality and improvement in maternal health outcomes in India.

METHODS

This study triangulates data from different rounds of Sample Registration Systems to assess the trend in maternal mortality in India. It further analysed the National Family Health Surveys (NFHS). NFHS-4, 2015-16 has gathered information on maternal mortality and pregnancy-related deaths from 601,509 households. Using logistic regression, we estimate the association of various socio-economic variables on maternal deaths in the various states of India.

RESULTS

On an average, wealth status of the households did not have a statistically significant association with maternal mortality in India. However, our disaggregate analysis reveals, the gains in terms of maternal mortality have been unevenly distributed. Although the rich-poor gap in maternal mortality has reduced in EAG states such as Bihar, Odisha, Assam, Rajasthan, the maternal mortality has remained above the national average for many of these states. The EAG states also experience supply side shortfalls in terms of availability of PHC and PHC doctors; and availability of specialist doctors.

CONCLUSIONS

The novel contribution of the present paper is that the association of household wealth status and place of residence with maternal mortality is statistically not significant implying financial barriers to access maternal health services have been minimised. This result, and India's impressive performance with respect to maternal health outcomes, can be attributed to the various pro-poor policies and cash incentive schemes successfully launched in recent years. Community-level involvement with pivotal role played by community health workers has been one of the major reasons for the success of many ongoing policies. Policy makers need to prioritise the underperforming states and socio-economic groups within the states by addressing both demand-side and supply-side measures simultaneously mediated by contextual factors.

Aberrant CREB1 activation in prostate cancer disrupts normal prostate luminal cell differentiation

The molecular mechanisms of luminal cell differentiation are not understood well enough to determine how differentiation goes awry during oncogenesis. Using RNA-Seq analysis, we discovered that CREB1 plays a central role in maintaining new luminal cell survival and that oncogenesis dramatically changes the CREB1-induced transcriptome. CREB1 is active in luminal cells, but not basal cells. We identified ING4 and its E3 ligase, JFK, as CREB1 transcriptional targets in luminal cells. During luminal cell differentiation, transient induction of ING4 expression is followed by a peak in CREB1 activity, while JFK increases concomitantly with CREB1 activation. Transient expression of ING4 is required for luminal cell induction; however, failure to properly down-regulate ING4 leads to luminal cell death. Consequently, blocking CREB1 increased ING4 expression, suppressed JFK, and led to luminal cell death. Thus, CREB1 is responsible for the suppression of ING4 required for luminal cell survival and maintenance. Oncogenic transformation by suppressing PTEN resulted in constitutive activation of CREB1. However, the tumor cells could no longer fully differentiate into luminal cells, failed to express ING4, and displayed a unique CREB1 transcriptome. Blocking CREB1 in tumorigenic cells suppressed tumor growth in vivo, rescued ING4 expression, and restored luminal cell formation, but ultimately induced luminal cell death. IHC of primary prostate tumors demonstrated a strong correlation between loss of ING4 and loss of PTEN. This is the first study to define a molecular mechanism whereby oncogenic loss of PTEN, leading to aberrant CREB1 activation, suppresses ING4 expression causing disruption of luminal cell differentiation.

An epidemic of avoidable caesarean deliveries in the private sector in India: Is physician-induced demand at play?

PURPOSE AND SETTING OF RESEARCH

Caesarean section (C-section) rates of over 15% suggest overuse of the surgery which may be difficult to justify on medical grounds. One important contributor to the rise in Csection rates is the rapid expansion of unregulated private-sector providers in number of settings. This study analyses the contribution of private sector in the rapid rise in Csection deliveries in India and the extent to which these can be justified on medical grounds.

METHODS

This is a cross sectional study design using National Family Health Surveys. Logistic regression and propensity score matching (PSM) analyses are performed. The main outcome measured is avoidable C-sections in the private sector.

PRINCIPAL FINDINGS

Our findings suggest that the rising trend in C-section rates in the private sector cannot be explained by medical reasons alone. The odds of C-section among women who chose to deliver in private was over 4 times higher than women who chose to delivery in public facilities. Despite, controlling for medical complications, women's characteristics and preferences, our PSM analysis suggest that the public-private gap has doubled over the years and that the difference cannot be explained by known determinants of C-section. Over supply of avoidable C-section to the extent of 21%, as a result of physician induced demand and perverse financial incentives was observed in the private sector.

CONCLUSIONS

This paper attempts to understand the reason for the high C-section rates in the private sector in India and the extent to which these are avoidable. Our analysis supports the assumption that physician induced demand as a result of perverse financial incentives in the private sector is at play.

Elastic Scattering and Reaction Cross-section of 8Li on 209Bi

Nuclear physics in the 21st century is driven by a quest to understand the properties of ever more exotic nuclear systems. Unusual structural phenom- ena are observed to arise in light weakly bound nuclei such as 8Li. 8Li has a cluster structure core of 7Li surrounded by a loosely bound neutron which is observed to influence reaction mechanisms near the fusion barrier. Elastic scat- tering provides a vital step towards understanding more complicated reaction mechanisms. In this work, elastic scattering was measured for 8Li + 2°9Bi at energies 2% to 34% above the barrier, allowing extraction of reaction cross- sections. The systematics of the reaction cross-sections of 8Li compared to neighbouring nuclei 6,7,9,11Li are discussed.

Mechanisms Suppressing Superheavy Element Yields in Cold Fusion Reactions

Superheavy elements are formed in fusion reactions which are hindered by fast nonequilibrium processes. To quantify these, mass-angle distributions and cross sections have been measured, at beam energies from below-barrier to 25% above, for the reactions of ^{48}Ca, ^{50}Ti, and ^{54}Cr with ^{208}Pb. Moving from ^{48}Ca to ^{54}Cr leads to a drastic fall in the symmetric fission yield, which is reflected in the measured mass-angle distribution by the presence of competing fast nonequilibrium deep inelastic and quasifission processes. These are responsible for reduction of the compound nucleus formation probablity P_{CN} (as measured by the symmetric-peaked fission cross section), by a factor of 2.5 for ^{50}Ti and 15 for ^{54}Cr in comparison to ^{48}Ca. The energy dependence of P_{CN} indicates that cold fusion reactions (involving ^{208}Pb) are not driven by a diffusion process.

Successful switch (tOPV to bOPV) in India: Tribute to a resilient health system

In accordance with the end game strategies for polio eradication a synchronized switch plan from tOPV to bOPV was implemented globally in 2016. The National Committee for Polio Eradication (NCCPE) validated the switch activities in India. An expert group of 104 academics conducted field visits in 25 states and 2 Union territories for independent verification (after an initial round of verification by the National Polio Surveillance Project [NPSP]). The objectives were to validate withdrawal and disposal of tOPV by screening cold chain points in public and private sector health facilities in both rural and urban areas; additionally, availability of bOPV and IPV was also documented. 34 filled tOPV and 5 empty vials were detected inside cold chain equipment and 17 outside. The disposal mechanism was found to be reasonably adequate. The key strategies -- 'throttling' of vaccine supplies well ahead of the switch date while preventing stock outs at various immunization points, simultaneously working with the regulators to delicense the tOPV on the switch date and helping manufacturers to calibrate vaccine production according to national timelines, and strong and persistent advocacy with professional associations to align with national bOPV and IPV policy facilitated successful accomplishment of the switch process. Effective implementation of the switch strategy in India also bears testimony to the resilience of the health system operating under diverse and heterogeneous governance.

Origins of Incomplete Fusion Products and the Suppression of Complete Fusion in Reactions of ^{7}Li

Above-barrier complete fusion involving nuclides with low binding energy is typically suppressed by 30%. The mechanism that causes this suppression, and produces the associated incomplete fusion products, is controversial. We have developed a new experimental approach to investigate the mechanisms that produce incomplete fusion products, combining singles and coincidence measurements of light fragments and heavy residues in ^{7}Li+^{209}Bi reactions. For polonium isotopes, the dominant incomplete fusion product, only a small fraction can be explained by projectile breakup followed by capture: the dominant mechanism is triton cluster transfer. Suppression of complete fusion is therefore primarily a consequence of clustering in weakly bound nuclei rather than their breakup prior to reaching the fusion barrier. This implies that suppression of complete fusion will occur in reactions of nuclides where strong clustering is present.

Optimization of beam dump shielding for K-130 cyclotron at VECC

A compact and efficient beam dump shield has been designed using Monte Carlo simulation code FLUKA to facilitate low background measurement of neutron and gamma rays using K130 cyclotron at Variable Energy Cyclotron Centre, Kolkata (VECC). Iron, lead and high density Polyethylene (HDPE) were considered in the design of the beam dump shield. Representative FLUKA simulation results have been validated using in-beam experiment performed on the same beam dump constituents. Experimental neutron and gamma-rays energy spectra have been found to be in fair agreement with the simulation results. Activation of various beam dump shield components were also carried out.

Studies of protein-protein interactions in Fanconi anemia pathway to unravel the DNA interstrand crosslink repair mechanism

Fanconi anemia (FA), a cancer predisposition syndrome exhibits hallmark feature of radial chromosome formation, and hypersensitivity to DNA crosslinking agents. A set of FA pathway proteins mainly FANCI, FANCD2 and BRCA2 are expressed to repair the covalent crosslink between the dsDNA. However, FA, BRCA pathways play an important role in DNA ICL repair as well as in homologous recombination repair, but the presumptive role of FA-BRCA proteins has not clearly explored particularly in context to function associated protein-protein interactions (PPIs). Here, in-vivo, in-vitro and in-silico studies have been performed for functionally relevant domains of FANCI, FANCD2 and BRCA2. To our conclusion, FANCI ARM repeat interacts with FANCD2 CUE domain and BRCA2 C-terminal region. Interestingly, FANCD2 CUE domain also interacts strongly with BRCA2 C-terminal region. Interactions between BRCA2 CTR and functionally relevant mutations Ser222Ala (cell cycle checkpoint mutant) and Leu231Arg (DNA ICL repair mutant) present in FANCD2 CUE domain have been analysed. To our finding, these mutations abrogate the binding between FANCD2 CUE domain and BRCA2 CTR. Furthermore, (1) different domain of FANCI, FANCD2 and BRCA2 are playing important role in PPIs, (2) mutations cause the impairment in the PPIs which in turn may disrupt the DNA ICL repair mechanism.

Experimental Determination of η/s for Finite Nuclear Matter

We present, for the first time, simultaneous determination of shear viscosity (η) and entropy density (s) and thus, η/s for equilibrated nuclear systems from A∼30 to A∼208 at different temperatures. At finite temperature, η is estimated by utilizing the γ decay of the isovector giant dipole resonance populated via fusion evaporation reaction, while s is evaluated from the nuclear level density parameter (a) and nuclear temperature (T), determined precisely by the simultaneous measurements of the evaporated neutron energy spectra and the compound nuclear angular momenta. The transport parameter η and the thermodynamic parameter s both increase with temperature, resulting in a mild decrease of η/s with temperature. The extracted η/s is also found to be independent of the neutron-proton asymmetry at a given temperature. Interestingly, the measured η/s values are comparable to that of the high-temperature quark-gluon plasma, pointing towards the fact that strong fluidity may be the universal feature of the strong interaction of many-body quantum systems.

Synthesis and Biological Studies of a Novel CB1 Antagonist

This paper describes the synthesis, early process development, salt selection strategies and pre clinical evaluation of novel, potent and selective CB1 antagonist, 8-Chloro-1-(2,4-dichloro-phenyl)-4,5-dihydro-1H-6-oxa-1,2-diaza-benzo[e]azulene-3-carboxylic acid piperidin-1-ylamide 1. The CB1 antagonism of compound 1 is also confirmed by reversal of CB1 agonist-induced hypothermia in Swiss albino mice. The process for the preparation of the compound 1 as a crystalline solid is also described. The crystalline form of the compound is found to be low bioavailable, therefore attempts have been made to improve its bioavailability through polymorphic transformation and salt formation. None of the salts prepared were found to be suitable for further development. The amorphous form of the compound 1 is found to be better suited. In vivo efficacy study of the amorphous form of compound 1 in 5% sucrose solution intake model in female Zucker fa/fa rats at single oral dose of 10 mg/kg demonstrates better reduction in the sucrose solution consumption than the corresponding crystalline form. The plasma concentration Cmax at AUC exposure of the amorphous form of the compound 1 is significantly improved and better than the Cmax of the corresponding crystalline form of the compound 1. On the basis of the efficacy, pharmacokinetic and toxicological evaluations, the compound 1 in the amorphous form is selected as a pre-clinical lead candidate.

Islet autoantibody status in a multi-ethnic UK clinic cohort of children presenting with diabetes

OBJECTIVE

We prospectively determined islet autoantibody status in children presenting with diabetes to a single UK region in relation to ethnicity.

DESIGN

316 (68.0% non-white) children presenting with diabetes between 2006 and 2013 were tested centrally for islet cell autoantibodies (ICA) and glutamic acid decarboxylase autoantibodies (GAD-65) at diagnosis, and if negative for both, tested for insulin autoantibodies (IAA). The assay used to measure GAD-65 autoantibodies changed from an in-house to a standardised ELISA method during the study.

RESULTS

Even with use of the standardised ELISA method, 25.8% of children assigned a diagnosis of type 1 diabetes still tested negative for all three autoantibodies. 30% of children assigned a diagnosis of type 2 diabetes were autoantibody positive, and these had the highest glycated haemoglobin (HbA1c) levels at 12 months follow-up compared with other groups (p value for analysis of variance <0.001), although the sample size was small. Autoantibody positivity was similar between non-white and white children regardless of assay used (60.0% (n=129) vs 56.4% (n=57), χ(2)=0.9, p=0.35), as was mean GAD-65 autoantibody levels, but fewer non-white children had two or more autoantibodies detectable (13% (n=28) vs 27.7% (n=28), χ(2)=12.1, p=0.001).

CONCLUSIONS

Islet autoantibody positivity was associated with a more severe phenotype, as demonstrated by poorer glycaemic control, regardless of assigned diabetes subtype. Positivity did not differ by ethnic group.

Screening of efficient arbuscular mycorrhizal fungi for Azadirachta indica under nursery condition: a step towards afforestation of semi-arid region of western India

To optimize nursery practices for efficient plant production procedures and to keep up to the ever growing demand of seedlings, identification of the most suitable species of arbuscular mycorrhizal fungi (AMF), specific for a given tree species, is clearly a necessary task. Sixty days old seedlings of Neem (Azadirachta indica A. Juss) raised in root trainers were inoculated with six species of AMF and a mixed inoculum (consortia) and kept in green house. Performances of the treatments on this tree species were evaluated in terms of growth parameters like plant height shoot collar diameter, biomass and phosphorous uptake capabilities. Significant and varied increase in the growth parameters and phosphorous uptake was observed for most of the AMF species against control. Consortia culture was found to be the best suited AMF treatment for A. indica, while Glomus intraradices and Glomus mosseae were the best performing single species cultures. It is the first time in the state of Gujarat that a wide variety of AMF species, isolated from the typical semi-arid region of western India, were tested for the best growth performance with one of the most important tree species for the concerned region.

Unvaccinated children in years of increasing coverage: how many and who are they? Evidence from 96 low- and middle-income countries

OBJECTIVE

While childhood immunisation coverage levels have increased since the 70s, inequities in coverage between and within countries have been widely reported. Unvaccinated children remain undetected by routine monitoring systems and strikingly unreported. The objective of this study was to provide evidence on the magnitude of the problem and to describe predictors associated with non-vaccination.

METHODS

Two hundred and forty-one nationally representative household surveys in 96 countries were analysed. Proportions and changes in time of 'unvaccinated' (children having not received a single dose of vaccine), 'partially vaccinated' and 'fully vaccinated' children were estimated. Predictors of non-vaccination were explored.

RESULTS

The percentage of unvaccinated children was 9.9% across all surveys. 66 countries had more than one survey: 38 showed statistically significant reductions in the proportion of unvaccinated children between the first and last survey, 10 countries showed increases and the rest showed no significant changes. However, while 18 of the 38 countries also improved in terms of partially and fully vaccinated, in the other 20 the proportion of fully vaccinated decreased. The predictors more strongly associated with being unvaccinated were education of the caregiver, education of caregiver's partner, caregiver's tetanus toxoid (TT) status, wealth index and type of family member participation in decision-making when the child is ill. Multivariable logistic regression identified the TT status of the caregiver as the strongest predictors of unvaccinated children. Country-specific summaries were produced and sent to countries.

CONCLUSION

The number of unvaccinated children is not negligible and their proportion and the predictors of non-vaccination have to be drawn from specific surveys. Specific vaccine indicators cannot properly describe the performance of immunisation programmes in certain situations. National immunisation programmes and national and international immunisation stakeholders should also consider monitoring the proportion of unvaccinated children (i.e. those who have received no vaccines at all) and draw specific plans on the determinants of non-vaccination.