The role of viral diagnostic tests in respiratory tract infections: moving forward.

The increased knowledge on virology and the increased potential of their diagnostic has risen several relevant question about the role of an early viral diagnosis and potential early treatment on the management of respiratory tract infections (RTI). In order to further understand the role of viral diagnostic tests in the management of RTI, a panel of experts was convened to discuss about their potential role, beyond what had been agreed in Influenza. The objective of this panel was to define the plausible role of aetiologic viral diagnostic into clinical management; make recommendations on the potential expanded use of such tests in the future and define some gaps in the management of RTI. Molecular Infection Viral Diagnostic (mIVD) tests should be used in all adult patients admitted to Hospital with RTI, and in paediatric patients requiring admission or who would be referred to another hospital for more specialised care. The increased use of mIVD will not only reduce the inappropriate use of antibiotics so reducing the antibiotic microbe resistance, but also will improve the outcome of the patient if an aetiologic viral therapy can be warranted, saving resource requirements and improving patient flows. Implementing IVD testing in RTI has various organizational benefits as well, but expanding its use into clinical settings would need a cost-effectiveness strategy and budget impact assessment.

[High-dose trivalent influenza vaccine: safety and immunogenicity]. / Vacuna antigripal trivalente de alta dosis: seguridad e inmunogenicidad.

Adults aged 65 years or older suffer the most severe health effects of seasonal flu. Although the influenza vaccine is effective in preventing influenza virus infection and its complications, it is not as effective in the elderly due to age-associated immunosenescence phenomenon. Since 2009, a high-dose trivalent influenza vaccine has been approved in the United States for the immunization of people ≥ 65 years with an antigen concentration four times higher than the standard vaccine. Multiple clinical trials carried out over different seasons, and using different methodologies, have shown that the high-dose trivalent influenza vaccine is not only more effective, but it also has a similar safety profile and is more immunogenic than the standard dose vaccine in the prevention of flu and its complications in the elderly. This document reviews the current scientific evidence on the safety and immunogenicity of high-dose influenza vaccine in people aged 65 years and over, and includes information from randomized clinical trials, observational studies with data from real clinical practice, and systematic reviews, and meta-analysis.

Genetic transformation of mosquitoes by microparticle bombardment.

Mosquitoes constitute the major living beings causing human deaths in the world. They are vectors of malaria, yellow fever, dengue, zika, filariases, chikungunya, among other diseases. New strategies to control/eradicate mosquito populations are based on newly developed genetic manipulation techniques. However, genetic transformation of mosquitoes is a major technical bottleneck due to low efficiency, the need of sophisticated equipment, and highly trained personnel. The present report shows the transgenerational genetic transformation of Aedes aegypti, using the particle inflow gun (PIG), by integrating the ecfp gene in the AAEL000582 mosquito gene with the CRISPR-Cas9 technique, achieving a mean efficiency of 44.5% of bombarded individuals (G0) that showed ECFP expression in their tissues, and a mean of 28.5% transformation efficiency measured on G1 individuals. The same transformation technique was used to integrate the egfp/scorpine genes cloned in the Minos transposon pMinHygeGFP into the Anopheles albimanus genome, achieving a mean efficiency of 43.25% of bombarded individuals (G0) that showed EGFP expression in their tissues. Once the technique was standardized, transformation of Ae. aegypti neonate larvae and An. albimanus eggs was achieved when exposed to gold microparticle bombardment. Integration of genes and heterologous protein expression were confirmed by PCR, sequencing, fluorescent microscopy, mass spectrometry, Western blot and dot blot analyses. Transgenerational inheritance of the transgenes was observed only on Ae. aegypti, as all transformed An. albimanus individuals died at the pupal stage of the G0 generation.

[High-dose trivalent influenza vaccine. Efficacy and effectiveness]. / Vacuna antigripal trivalente de alta dosis. Eficacia y efectividad.

Seasonal influenza is a major public health problem, particularly in older people. Influenza vaccine is the most effective way to prevent influenza virus infection and its complications, but due to immunosenescence, older people do not respond efficiently to immunization. In 2009, a high-dose trivalent influenza vaccine (IIV3-HD), containing four times more antigen than the standard-dose vaccine, was approved in the United States for the immunization of people aged 65 years and over. Numerous clinical trials, carried out at different seasons and using different methodologies, have shown that the IIV3-HD vaccine is, as well as safe, more immunogenic and more effective than the standard-dose vaccine in preventing influenza virus infection and its complications in older people. This paper reviews the available evidence on the efficacy and effectiveness of the IIV3-HD influenza vaccine in the elderly, with information from randomized clinical trials, as well as observational studies of real-world clinical practice and in systematic reviews/meta-analyses.

The situation of vaccines for the prevention of infections in adults: An opinion paper on the situation in Spain.

The childhood immunization schedule is well known and generally well implemented in developed countries. For various reasons, the same is not true of vaccines aimed at preventing infections in adults, in which vaccination coverage is incomplete and generally very deficient. In order to assess the situation of adult vaccination in Spain, the Fundación de Ciencias de la Salud has brought together a series of experts in different fields, including doctors, nurses, representatives of patient associations, health managers and economists, health authorities and journalists to deal with this issue. The format was that of a round table in which a series of questions previously formulated by the coordinators were to be answered and debated. The document presented is not an exhaustive review of the topic, nor is it intended to make recommendations, but only to give a multidisciplinary opinion on topics that could be particularly debatable or controversial. The paper reviews the main vaccine-preventable adult diseases, their clinical and economic impact, the possibilities of reducing them with vaccination programmes and the difficulties in carrying them out. The role of nursing, pharmacy services, patient associations and the health administration itself in changing the current situation was discussed. Prospects for new vaccines were discussed and we speculated on the future in this field. Finally, particularly relevant ethical aspects in decision-making regarding vaccination were discussed, which must be faced by both individuals and states. We have tried to summarize, at the end of the presentation of each question, the environment of opinion that was agreed with all the members of the table.

[Description of Influenza B in seasonal epidemics in Spain]. / Descripción de la gripe B en las epidemias estacionales de España.

OBJECTIVE: Seasonal influenza epidemics are a major public health concern. They are caused by the influenza A and B viruses; although the A virus is more prominent, influenza B virus infection causes a disease with similar characteristics. There are two phylogenetically distinct influenza B lineages (B/Victoria and B/Yamagata), only one of which is present in the trivalent vaccine formulated each season. METHODS: Epidemiological data from the Spanish Influenza Surveillance System for 2007 to 2017 were reviewed to establish the relative proportion of each type of virus and the characterization of the B lineages in relation to the composition of the trivalent vaccine. RESULTS: The median proportion of B (2007-2017) was 27.2% (0.7%-74.8%) vs. 16.3% (0.4%-98.6%) for A-H3 and 44.2% (0.1%-98.0%) for pandemic A-H1N1 (20092017). The B lineages co-circulated in 8/10 seasons and there was mismatch with the B vaccine strain in 4/10 seasons. The B virus was dominant in 2007/08 and 2012/13 throughout Spain. There was a combination of dominance/codominance of influenza B and mismatch with the vaccine lineage in at least one third of epidemic seasons reviewed. CONCLUSIONS: Epidemiological information on influenza B has been less compiled in comparison with data on the A virus. Influenza virus type B is responsible for a significant number of cases in almost all seasons. The predominant B lineage in each season is unpredictable, affecting the protection conferred by the seasonal vaccine. Spanish epidemiological data support the rationale for a quadrivalent vaccine with both B virus lineages similarly to data from other settings.

[Prevalence of human papillomavirus in Spanish women from a population screening program]. / Prevalencia de virus del papiloma humano en mujeres españolas de un programa de cribado poblacionales de riesgo.

OBJECTIVE: The human papillomavirus (HPV), is necessary to cause a woman developing cervical cancer. The aim of the study was to estimate the prevalence of women with HPV infection, covered by the program of prevention and early detection of cervical cancer of Castile and León (Spain). METHODS: Samples of women included in the screening program were analyzed. Including a total of 120,326 cervical swab samples, collected in the period from January 2012 to December 2014. RESULTS: 12,183 HPV positive samples were detected, representing a prevalence of 9.6 ‰, (IC 95% 9.5%-9.8%) in the female population. High-risk HPV were found in higher proportion that HPV low-risk genotypes. HPV prevalence correlates inversely with women age. Coinfections of multiple genotypes were found in one third of screened women population. CONCLUSIONS: Data showed in this study are the first and wider Spanish results from a cervical cancer screening program population non opportunistic based on HPV detection. These results would serve as a reference for future prevalence studies and to evaluate the future impact of HPV vaccination campaigns.

Suppressor of hairy-wing, modifier of mdg4 and centrosomal protein of 190 gene orthologues of the gypsy insulator complex in the malaria mosquito, Anopheles stephensi.

DNA insulators organize independent gene regulatory domains and can regulate interactions amongst promoter and enhancer elements. They have the potential to be important in genome enhancing and editing technologies because they can mitigate chromosomal position effects on transgenes. The orthologous genes of the Anopheles stephensi putative gypsy-like insulator protein complex were identified and expression characteristics studied. These genes encode polypeptides with all the expected protein domains (Cysteine 2 Histidine 2 (C2H2) zinc fingers and/or a bric-a-brac/poxvirus and zinc finger). The mosquito gypsy transcripts are expressed constitutively and are upregulated in ovaries of blood-fed females. We have uncovered significant experimental evidence that the gypsy insulator protein complex is widespread in vector mosquitoes.

Tendencia y estacionalidad del virus respiratorio sincitial en Valladolid durante el periodo 1993-2010 / Trend and seasonality of respiratory syncytial virus in Valladolid (Spain) during 1993-2010

Objetivo: Describir la tendencia y la estacionalidad de las infecciones por el virus respiratorio sincitial (VRS) en el Área de Salud de Valladolid Este durante el periodo 1993-2010.Pacientes y métodos: Se incluyeron en el estudio las muestras analizadas entre enero de 1993 y diciembre de 2010 por el Servicio de Microbiología e Inmunología del Hospital Clínico Universitario de Valladolid. Las muestras se clasificaron en función de la edad del paciente y el método de diagnóstico. El análisis virológico se llevó a cabo mediante técnicas de diagnóstico rápido, cultivo celular o microarrays. Se calcularon las tasas anuales referidas al área cubierta por el hospital para identificar la tendencia desde 1993 hasta 2010. Los meses epidémicos se establecieron mediante el índice epidémico, y la periodicidad mediante el método cosinor. Resultados: De 4.103 muestras analizadas de pacientes con síntomas respiratorios, en 1.644 (40,1%) se confirmó la presencia de VRS. Casi el 90% de los casos confirmados se dieron en pacientes menores de 2 años, y el 59,5% en menores de 1 año. Las tasas fluctuaron cada 2-4 años, alcanzando valores máximos en 2002 y 2003, con 41,5 y 44,9 casos por 100.000 habitantes-año, respectivamente. Aunque se produjeron casos durante todo el año, los periodos epidémicos se dieron entre septiembre y marzo, detectándose la mayor incidencia en enero y la menor en julio. Conclusiones: Los datos epidemiológicos (prevalencia del virus en muestras respiratorias y distribución por edad) fueron similares a los descritos en otros estudios. Los periodos epidémicos se describieron entre septiembre y marzo, alcanzado el máximo de incidencia en enero y el mínimo en julio. A pesar de ello, a lo largo de los 18 años estudiados sólo en 5 años no hubo circulación de VRS durante 2-3 meses, y en 8 más el VRS estuvo ausente durante un mes. No hay ningún dato que permita anticipar la ausencia de circulación del virus, aspecto importante para la profilaxis de esta infección (AU)

Purpose: The aim of the study is to describe the trend and seasonality of respiratory syncytial virus (RSV) infections in the East Valladolid Health Administrative-Division during the period1993-2010.Patients and Methods: Samples processed in the area of Eastern Valladolid by the Department of Microbiology and Immunology at the Hospital Clínico Universitario of Valladolid between January 1993 and December 2010 were included in the analysis. Cases were classified by age and diagnostic method. Virological diagnosis of the cases was carried out through rapid assay methods, shell-vial cell culture assay or microarray techniques. Annual rates were calculated to identify the trend of the infection from 1993 to 2010. The epidemic index was used to establish epidemic months and cosinor method to evaluate periodicity. Results: From 4,103 samples processed, collected from patients with respiratory symptoms, 1,644 (40.1%) were confirmed to be RSV possitive. Almost 90% of the confirmed cases appeared in patients under 2 years old, 59.5% in younger than1 year old children. The infection trend seems to fluctuate every 2-4 years with higher rate in 2002 and 2003, accounting for 41.5 and 44.9 cases detected per 100,000 inhabitants-year, respectively. Although cases were detected throughout all the year, epidemic periods were detected from September to March with highest values in January and lowest values in July. Conclusions: Epidemiological data (VRS prevalence in respiratory samples and distribution of cases by age) was similar to those obtained in previous studies. Epidemic periods were described from September to March with the highest numbers of cases in January and lowest values in July. In spite of this, along the eighteen years studied there were eight years without RSV detection in one month and only five years without detection in 2-3 months. There is no data that allows to predict the lack of circulation for RSV, being an important factor for the prophylaxis of the infection (AU)

Respuesta inmune respiratoria al año de vida en el niño prematuro / Respiratory immune response in first year of a preterm infant

Introducción: Existe un gran desconocimiento acerca de la evolución del sistema inmune en la mucosa respiratoria del niño prematuro a largo plazo. La inmadurez y las infecciones respiratorias pueden influir sobre la respuesta inmune de las mucosas. El propósito de este estudio era evaluar la secreción respiratoria de los mediadores inmunológicos al año de vida en niños prematuros. Pacientes y métodos: Desde octubre de 2008 hasta abril de2009 se reclutaron 77 prematuros nacidos en 6 servicios de pediatría de Castilla y León, así como 14 controles sanos a término. Los prematuros fueron citados al año de edad gestacional corregida y los niños a término al año de vida, momento en el cual se les realizó un lavado nasal para determinar los niveles de 27 mediadores inmunológicos mediante un ensayo de Biorad®. Resultados: Los niños prematuros tenían niveles más elevados de quimiocinas (eotaxina, IP-10), citocinas Th-1 (IFN-epsilon), Th-2 (IL-13), Th-17 (IL-17) y factores de crecimiento celular (PDGF-bb, VEGF, FGF-b, G-CSF y GM-CSF) que los niños a término. Cuando se compararon los niveles de mediadores entre los niños que habían recibido profilaxis para el virus respiratorios incitial con palivizumab y los que no, los segundos tenían niveles significativamente más altos de MCP-1, IL-1RA, IL-10,IL-12p70 y VEGF (p <0,05) que los primeros. Conclusiones: Este trabajo demuestra por vez primera la influencia de la prematuridad sobre los perfiles de secreción respiratoria de las citocinas y quimiocinas a largo plazo. Por otra parte, nuestros resultados indican que la evaluación del impacto de la profilaxis de la infección respiratoria es un camino interesante para comprender la maduración de la respuesta inmune de la mucosa respiratoria del prematuro(AU)

Introduction: There is a big unawareness about a long term respiratory mucous immune system evolution in the preterm infant. Immaturity and respiratory infections can have a big influence on the mucous immune responses. This investigation’s purpose is the evaluation of respiratory secretion of inflammatory immunological mediators in the first year of a preterm infant. Patients and methods: Between October 2008 and April 2009, 77 preterm infants were born in 6 pediatric services of Castilla y Leon, plus to another 14 healthy controls results. Children were invited on their first corrected gestational age and the ones of healthy controls results. Nasal washing were applied to determine 27 immunological mediators’ levels by applying a Biorad test. Results: The preterm infants has higher chemokine (eotaxin,IP-10), cytokines Th-1 (IFN-epsilon), Th-2 (IL-13), Th-17 (IL-17) and cell growing factors (PDGF-bb, VEGF, FGF-b, G-CSF and GM-CSF)levels than a healthy control results children. When a comparison was made between children that received prophylaxis for their respiratory syncytial virus with palivizumab and the ones that did not receive it, the second group showed higher MCP-1, IL-1RA, IL-10, IL-12p70 and VEGF (p <0,05) levels. Conclusions: This work proves, for the first time, the influence of the premature birth on chemokine and cytokines respiratory secretion levels in a long term concepts. On other hand, our results indicate that prophylaxis impact in the respiratory infection is an interesting way to understand respiratory mucous immune response maturation in the preterm infant(AU)

[Variability in the sensitivity to tigecycline against Acinetobacter baumannii in different culture media]. / Variabilidad en la sensibilidad de tigeciclina frente a Acinetobacter baumannii en diferentes medios de cultivo.

INTRODUCTION: The tigecycline may represent a therapeutic alternative for the control of multiresistant A. baumannii, although there is no consensus regarding the cutoff points for sensitivity or variability of MIC as a function of culture medium used for the antibiogram against this microorganism. Therefore, our objective was to verify this variability, and propose the culture medium that comes closest to the standard method. METHODS: We selected 41 strains of carbapenem-resistant A. baumannii. We analyzed the sensitivity to tigecycline in different culture media: Mueller Hinton agar Oxoid commercial (C-MH), Mueller Hinton fresh agar BD and Co., USA (F-MH) and ISO-sensitest fresh agar Oxoid, using the E-test and disk. The MICs were compared against those obtained using the technique standard of macrodilution. RESULTS: The mean MIC and inhibition diameters obtained in the different culture media corresponded to 9.26 mg/L and 15.1 mm in diameter for MH-C, 1.71 mg/L and 22.7 mm for MH-F; 2.68 mg/L and 20.8 mm for ISO-sensitest. Half the MIC obtained by the standard method of dilution was 0.47 mg/L (SD =0.21), with values between 0.25 and 1 mg/L. CONCLUSION: In the three growth media studied, MICs superior to the standard are observed, which is false to interpret resistance in many cases. However, the medium that comes closer more that of reference is the MH-F.

Influence of testing methodology on the tigecycline activity profile against presumably tigecycline-non-susceptible Acinetobacter spp.

OBJECTIVES: To compare the tigecycline activity profile against Acinetobacter spp. by Etest versus broth microdilution in isolates with high Etest MIC. METHODS: Acinetobacter spp. isolates with tigecycline MICs of >or=0.5 mg/L determined by commercially developed Etests strips (January 2006 to July 2007) in five Spanish hospitals were considered. Values were rounded to the nearest upper double-dilution. Susceptibility by broth microdilution following CLSI (formerly NCCLS) recommendations, as the reference method, was determined in a central laboratory. BSAC breakpoints were used: susceptible 2 mg/L. RESULTS: One hundred and forty-eight isolates were collected: 12 isolates with a tigecycline Etest MIC of 0.5 mg/L, 14 with 1 mg/L, 86 with 2 mg/L, 31 with 4 mg/L and 5 with 8 mg/L. Isolates with Etest MICs of 0.5-1 mg/L showed the same values by broth microdilution. Among isolates with Etest MICs of 2 mg/L, only 5.8% of strains showed the same value by both methods (88.4% showed values that were one or two dilutions lower by microdilution). None of the 36 isolates with Etest MICs of 4-8 mg/L showed the same value by both methods, with values at least two dilutions lower by microdilution. Weak correlation (R = 0.238; P or=2 mg/L for Acinetobacter spp. since strains with Etest MICs of 2-4 mg/L are susceptible when tested by microdilution. False non-susceptibility by Etest may exclude tigecycline as a therapeutic option in a field where multiresistance is the rule.

Viral Load in Spanish HIV patients: trends since the introduction of HAART.

The aim of this study is to describe trends in the percentage of samples with undetectable HIV viral load in Spain after the implementation of HAART. A descriptive observational study of HIV-VL measurements carried out in the microbiology department of the Hospital Clínico Universitario de Valladolid (HCUV) was conducted over a 9-year period (1996-2004). Regarding the trend over the study period, the 30-39 years age group accounted for most of the samples, although the percentage decreased from 65.5% to 59.6% over the study period. In contrast, the 40-49 years group increased from 9.1% to 14.5%. The preponderance of men, with percentages above 70%, was observed during the whole period. Although the purpose of this treatment is to maintain undetectable viral loads, since 1999 more than 60% of nonfirst samples had detectable levels. Based on the results of the VL trend among HIV/AIDS patients observed in this study, a large number of patients maintain elevated detectable VL years after HAART was implemented. Although different factors may be the cause of this and should be delimited in future studies, the phenomenon observed demonstrates the usefulness of monitoring VL and analyzing its time trend to gain further knowledge about the therapeutic results and care of HIV patients as a whole, also serving as the basis for corrective measures.

Viral Load in Spanish HIV patients: trends since the introduction of HAART

The aim of this study is to describe trends in the percentageof samples with undetectable HIV viral load in Spain afterthe implementation of HAART. A descriptive observationalstudy of HIV-VL measurements carried out in themicrobiology department of the Hospital Clínico Universitariode Valladolid (HCUV) was conducted over a 9-year period(1996-2004).Regarding the trend over the study period, the 30-39years age group accounted for most of the samples, althoughthe percentage decreased from 65.5 % to 59.6%over the study period. In contrast, the 40-49 years group increasedfrom 9.1 % to 14.5 %. The preponderance of men,with percentages above 70 %, was observed during thewhole period.Although the purpose of this treatment is to maintainundetectable viral loads, since 1999 more than 60% of nonfirstsamples had detectable levels.Based on the results of the VL trend among HIV/AIDSpatients observed in this study, a large number of patientsmaintain elevated detectable VL years after HAART was implemented.Although different factors may be the cause ofthis and should be delimited in future studies, the phenomenonobserved demonstrates the usefulness of monitoringVL and analyzing its time trend to gain furtherknowledge about the therapeutic results and care of HIVpatients as a whole, also serving as the basis for correctivemeasures (AU)

en el porcentaje de muestras con carga viral(CV) de VIH indetectable en una serie española, despuésde la introducción de la terapia antirretroviral de altaeficacia (HAART). Se ha llevado a cabo un estudio descriptivoobservacional de las determinaciones de CV deVIH realizadas en el departamento de microbiología delHospital Clínico Universitario de Valladolid (HCUV) duranteun período de 9 años (1996-2004). Las muestrasprocedentes de individuos cuya categoría de edad se encontrabaen el intervalo de 30-39 años fueron las masnumerosas, y la proporción de CV indetectables en estegrupo disminuyó del 65,5% al 59,6% durante el períodode estudio. Al contrario en el grupo de 40-49 años aumentódel 9,1% al 14,5%. Los varones, con porcentajesencima del 70%, fueron el grupo preponderante duranteel período entero.De acuerdo con nuestros hallazgos un porcentaje importantede pacientes (más del 60%) mantiene niveles deCV detectable en las muestras de seguimiento, a pesarde la introducción de las terapias «HAART» desde 1999.La presente aportación demuestra la utilidad de monitorizarla CV y su tendencia en el tiempo, como indicadorde la eficiencia terapéutica; aunque sean necesariosestudios futuros que pueden matizar los factores involucradosen este hecho de cara a optimizar los cuidados yla terapia de los pacientes con infección VIH (AU)

Situación actual de la nueva gripe H1N1 / Current situation of the new H1N1 flu

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Recombinant scorpine: a multifunctional antimicrobial peptide with activity against different pathogens.

Scorpine is an antimicrobial peptide whose structure resembles a hybrid between a defensin and a cecropin. It exhibits antibacterial activity and inhibits the sporogonic development of parasites responsible for murine malaria. In this communication we report the production of scorpine in a heterelogous system, using a specific vector containing its cloned gene. The recombinantly expressed scorpine (RScp) in (Anopheles gambie) cells showed antibacterial activity against (Bacillus subtilis) and (Klebsiella pneumoniae), at 5 and 10 microM, respectively. It also produced 98% mortality in sexual stages of (Plasmodium berghei) at 15 microM and 100% reduction in (Plasmodium falciparum) parasitemia at 5 microM. RScp also inhibited virus dengue-2 replication in C6/36 mosquito cells. In addition, we generated viable and fertile transgenic (Drosophila) that overexpresses and correctly secretes RScp into the insect hemolymph, suggesting that the generation of transgenic mosquitoes resistant to different pathogens may be viable.

[Social and economic impact of chicken pox vaccine at 15 months of age. Castile and Leon, Spain, 2004]. / Impacto social y económico de la vacunación frente a la varicela a los 15 meses de edad en Castilla y León en 2004.

BACKGROUND: Chicken pox is a mainly childhood contagious disease caused by the Varicella Zoster Virus which gives rise to major healthcare and social costs. In 2005, Castile and Leon added chicken pox vaccine injections to its childhood vaccination schedule for eleven year-olds subject to coming down with this disease. This strategy does not modify the major mobility generated thereby at younger ages. This study is aimed at evaluating the profitability of systematic vaccination for chicken pox in infants 15 months of age in Castile and Leon. METHODS: An economic cost-benefit evaluation has been set out by jeans of a decision-making tree. A fictitious cohort of 100,000 children in Castile and Leon having reached 15 months of age in 2004 is studied, to whom the chicken pox vaccine would be administered in conjunction with the mumps, measles, rubella vaccines. This study is approached from the social standpoint. The time horizon selected was that of up until the study cohort was to reach 15 years of age, applying a 3% discount rate. A sensitivity analysis was made for evaluating the uncertainty of some variables... RESULTS: The cost-benefit ratio of adding this vaccine to the childhood vaccination schedule amounts to 1.23. CONCLUSIONS: From the social standpoint, administering chicken pox vaccine in conjunction with the mumps, measles, rubella vaccines show itself to be profitable. The profitability is modified both if a second dose of vaccine is added as well as if only the direct healthcare costs are analyzed.