The use of antibiotics in the treatment of pediatric varicella patients: real-world evidence from the multi-country MARVEL study in Latin America & Europe.

BACKGROUND: Varicella is a highly contagious childhood disease. Generally benign, serious complications necessitating antibiotic use may occur. The objective of this study was to characterize the rate, appropriateness and patterns of real-world antibiotic prescribing for management of varicella-associated complications, prior to universal varicella vaccination (UVV) implementation. METHODS: Pooled, post-hoc analysis of 5 international, multicenter, retrospective chart reviews studies (Argentina, Hungary, Mexico, Peru, Poland). Inpatient and outpatient primary pediatric (1-14 years) varicella cases, diagnosed between 2009 and 2016, were eligible. Outcomes, assessed descriptively, included varicella-associated complications and antibiotic use. Three antibiotic prescribing scenarios were defined based on complication profile in chart: evidence of microbiologically confirmed bacterial infection (Scenario A); insufficient evidence confirming microbiological confirmation (Scenario B); no evidence of microbiological confirmation (Scenario C). Stratification was performed by patient status (inpatient vs. outpatient) and country. RESULTS: Four hundred one outpatients and 386 inpatients were included. Mean (SD) outpatient age was 3.6 (2.8) years; inpatient age was 3.1 (2.8) years. Male gender was predominant. Overall, 12.2% outpatients reported ≥1 infectious complication, 3.7% ≥1 bacterial infection, and 0.5% ≥1 microbiologically confirmed infection; inpatient complication rates were 78.8, 33.2 and 16.6%, respectively. Antibiotics were prescribed to 12.7% of outpatients and 68.9% of inpatients. Among users, ß-lactamases (class), and clindamycin (agent), dominated prescriptions. Scenario A was assigned to 3.9% (outpatients) vs 13.2% (inpatients); Scenario B: 2.0% vs. 6.0%; Scenario C: 94.1% vs. 80.8%. CONCLUSIONS: High rates of infectious complications and antibiotic use are reported, with low rates of microbiological confirmation suggesting possible antibiotic misuse for management of varicella complications.

Impact and effectiveness of meningococcal vaccines: a review.

OBJECTIVES: To summarize and critically evaluate the evidence on the impact and effectiveness of meningococcal vaccination programs around the world in order to inform decisionmaking in Latin America and the Caribbean. METHODS: A review of the literature was conducted following several components of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed Central® was searched for papers published in any language from January 1999 - March 2017. RESULTS: In all, 32 studies were included, most of which evaluated the meningococcal C conjugate vaccine. Fourteen studies measured effectiveness and 30 measured impact. The effectiveness of polysaccharide vaccines was 65% - 83.7% (different age groups), while the effectiveness of the conjugate vaccines was 66% - 100%. Incidence decline of laboratory-confirmed meningococcal disease for the conjugate vaccine ranged from 77% - 100% among different ages groups. The only study that evaluated the protein subunit vaccine reported a vaccine effectiveness of 82.9%. CONCLUSIONS: The studies reviewed show impact and effectiveness of both polysaccharide vaccines and conjugate vaccines on vaccine-serogroup meningococcal disease. The conjugate vaccines, however, show higher impact and effectiveness with longer-lasting protection over the polysaccharide vaccines. Given the variance in potential use of a meningococcal vaccine, epidemiological surveillance systems should be strengthened to inform national decisions.

The economic rationale for cell-based influenza vaccines in children and adults: A review of cost-effectiveness analyses.

Seasonal influenza significantly affects both health and economic costs in children and adults. This narrative review summarizes published cost-effectiveness analyses (CEAs) of cell-based influenza vaccines in children and adults <65 years of age, critically assesses the assumptions and approaches used in these analyses, and considers the role of cell-based influenza vaccines for children and adults. CEAs from multiple countries demonstrated the cost-effectiveness of cell-based quadrivalent influenza vaccines (QIVc) compared with egg-based trivalent/quadrivalent influenza vaccines (TIVe/QIVe). CEA findings were consistent across models relying on different relative vaccine effectiveness (rVE) estimate inputs, with the rVE of QIVc versus QIVe ranging from 8.1% to 36.2% in favor of QIVc. Across multiple scenarios and types of analyses, QIVc was consistently cost-effective compared with QIVe, including in children and adults across different regions of the world.

Estimating the health economic impact of the universal varicella vaccination in Argentina from 2015 to 2019.

Since the introduction of Universal Varicella Vaccination (UVV) in the Argentinean National Immunization Program in 2015, a significant decline in the incidence of varicella has been reported. This study aimed to estimate the economic impact of single-dose UVV in Argentina from 2015 to 2019. The economic impact was assessed based on the observed incidence of varicella in the post-UVV period and the number of cases avoided, obtained from a previously published study that used an Autoregressive Integrated Moving Average (ARIMA) model. The weighted average cost per case was calculated using local studies. The post-UVV cost reductions were calculated by multiplying the number of cases avoided from 2015 -2019 by the weighted average cost per case. Data were summarized yearly and by peak (September-November) periods for the target (1-4 years) and overall populations. We estimated avoided costs of United States dollars (USD) $65 million in the target population and $112 million in the overall population over 4 years following UVV introduction. We observed a trend toward greater reductions in costs over time, with substantial differences observed in peak periods. We estimated that the single-dose UVV program considerably reduced the economic burden of varicella in Argentina by avoiding direct and indirect costs associated with varicella management.

Meningococcal burden of disease in Argentina: 10 years epidemiologic review.

Invasive meningococcal disease (IMD) is an uncommon but serious and potentially fatal condition, mainly affecting infants. In 2017, Argentina introduced a vaccination program against serogroups A, C, W and Y (MenACWY) for infants aged 3, 5 and 15 months and adolescents aged 11 years. The objective of this study was to review the burden of IMD in Argentina in 2010-2019. Data were obtained from national surveillance databases, and the study estimated IMD incidence, mortality, case-fatality rates, and serogroup distributions across age groups. A total of 1,972 IMD cases were reported in the study period, with the highest incidence in infants aged < 1 year. Incidence peaked in 2013 and subsequently declined. Mortality rates were 18 times higher in infants than in other age groups, reflecting the high impact of IMD in this age group. The case-fatality rate was 8.5% on average and increased with age. The proportion of notified cases with serogroup identification increased over the period, reaching 91% in 2019. The most common serogroups over the study period were serogroup B (48%) and serogroup W (42%), with an increase in B relative to W since 2015. In infants aged < 1 year, the proportion of serogroup B increased in recent years, reaching around 70% of characterized cases in 2018-2019. These results show the dynamism of IMD and indicate the importance of vaccination at an early age and offering protection against predominant serogroups. These data are valuable to support evidence-based decision-making in healthcare.

Real-World Evidence in Cost-Effectiveness Analysis of Enhanced Influenza Vaccines in Adults ≥ 65 Years of Age: Literature Review and Expert Opinion.

Influenza vaccination can benefit most populations, including adults ≥ 65 years of age, who are at greater risk of influenza-related complications. In many countries, enhanced vaccines, such as adjuvanted, high-dose, and recombinant trivalent/quadrivalent influenza vaccines (aTIV/aQIV, HD-TIV/HD-QIV, and QIVr, respectively), are recommended in older populations to provide higher immunogenicity and increased relative vaccine efficacy/effectiveness (rVE) than standard-dose vaccines. This review explores how efficacy and effectiveness data from randomized controlled trials and real-world evidence (RWE) are used in economic evaluations. Findings from published cost-effectiveness analyses (CEA) on enhanced influenza vaccines for older adults are summarized, and the assumptions and approaches used in these CEA are assessed alongside discussion of the importance of RWE in CEA. Results from many CEA showed that adjuvanted and high-dose enhanced vaccines were cost-effective compared with standard vaccines, and that differences in rVE estimates and acquisition price may drive differences in cost-effectiveness estimates between enhanced vaccines. Overall, RWE and CEA provide clinical and economic rationale for enhanced vaccine use in people ≥ 65 years of age, an at-risk population with substantial burden of disease. Countries that consider RWE when making vaccine recommendations have preferentially recommended aTIV/aQIV, as well as HD-TIV/HD-QIV and QIVr, to protect older individuals.

Efficacy of an extensively hydrolyzed formula with the addition of synbiotics in infants with cow's milk protein allergy: a real-world evidence study.

Introduction: Cow's milk protein allergy (CMPA) is the most frequent food allergy in early childhood. For those infants requiring breastmilk substitutes, formulas with extensively hydrolyzed proteins (EHF), should be the treatment of choice. As there are limited data showing the progression of initial symptoms in infants newly diagnosed with CMPA who are treated with EHF with added synbiotics, the main objective of this study was to evaluate the resolution of symptoms in said infants after 4 weeks of treatment. As a secondary objective this study aimed to assess the impact of the treatment on the family's quality of life. Materials and Methods: observational, longitudinal, prospective, and multicentric real-world evidence study. The intervention phase (EHF with synbiotics) lasted 28 days and was completed by 65 patients. Treating physicians registered child´s anthropometry, Infant Gastrointestinal Symptoms Questionnaire (IGSQ-13) and CoMiSS (Cow´s Milk Allergy Symptoms Score) both at baseline and after 28 days of treatment. During treatment, caregivers reported child´s regurgitation and stools, PO-SCORAD (Patient Oriented Scoring of Atopic Dermatitis) and FAQL-PB (Family Quality of Life-Parental Burden). Data were collected using Google Forms and analyzed through the STATA program. Results: 95.4% of the patients showed an improvement or disappearance of the overall initial symptoms after 4 weeks of treatment. Gastrointestinal symptoms improved or disappeared in 92% of patients (p < 0.05) while dermatological symptoms improved or disappeared in 87.5% of patients (p < 0.05). The median CoMiSS at baseline was 9, with 21 patients exceeding the cut-off point of 12. After 4 weeks of treatment, the median dropped to 3, and no patient exceeded the 12-cut-off point (p = 0.000). At baseline, patients had a PO-SCORAD of 11.5 (interquartile range 1-23) that went to 1.0 (interquartile range 1-6) at day 28 (p = 0.000). The treatment diminished stool frequency (p < 0.05), improved stool consistency (p = 0.004) and decreased the frequency of regurgitation in infants with CMPA (p = 0.01). The percentage of patients who no longer had any episode of regurgitation increased from 11% to 31% on day 28 (p = 0.003). At baseline, 13% of patients cried more than 3 h per day, while at day 28 that percentage dropped to 3% (p = 0.03). An improvement in the infants' sleep pattern was also appreciated with the treatment. At study onset, 56% of the families reported feeling very overwhelmed, a percentage that dropped to 17% after 28 days of treatment (p < 0.05). The small percentage of families who did not feel overwhelmed at study onset (17%), grew to 43% on day 28 (p < 0.05). Conclusions: The use of an EHF with synbiotics for the management of infants diagnosed with or suspected to have CMPA suggested a good safety profile, an adequate infant growth, and improvement of overall, gastrointestinal, and dermatological symptoms. It also suggested a lower daily frequency of regurgitations and stools, and an improvement in stool consistency, sleeping pattern, and quality of life of the infant and his family.

Cost-Effectiveness of Pneumococcal Vaccines for Adults Aged 65 Years and Older in Argentina.

OBJECTIVES: In 2017, the Argentine Ministry of Health incorporated a sequential 13-valent pneumococcal conjugate vaccine (PCV13)-23-valent pneumococcal polysaccharide vaccine (PPSV23) regimen for adults aged ≥65 years to reduce pneumococcal disease burden. Cost-effectiveness analysis of PCV13-PPSV23 schedule for adults aged ≥65 years in Argentina was performed compared with PPSV23 only. METHODS: Markov model was developed. Local data were incorporated for costs and disease burden analysis. Vaccine efficacy or effectiveness was obtained from a systematic review adjusted to current local vaccine serotype circulation and vaccines coverage. A total of 3 scenarios were evaluated: main scenario according to published literature of pneumonia incidence, epidemiologic surveillance scenario based on Argentine Ministry of Health data, and an alternative scenario assuming a 50% hypothetical pneumonia incidence reduction resulting from herd immunity induced by childhood vaccination. Sensitivity analyses were done. RESULTS: Sequential PCV13-PPSV23 schedule showed cost-savings results in the main scenario with -$1 667 742.23 saved and 716 life-years gained (LYG). The epidemiologic surveillance scenario showed an incremental cost-effectiveness ratio of $2141.92 per LYG and an alternative scenario with $3740.30 per LYG. Tornado diagram shows widest bars related to adjustment for vaccine-type pneumococcal pneumonia (urine analysis) pneumonia at risk cost and pneumonia incidence rate. Monte Carlo simulation shows that >98% of simulations were cost-saving for the main scenario. CONCLUSIONS: In the main scenario, cost-saving results were obtained considering only reduction of vaccine serotype coverage after the introduction of childhood PCV13 vaccination. In the epidemiologic surveillance and alternative scenarios, assuming a hypothetical incidence reduction, highly cost-effective results were observed.

Outpatient management of childhood acute diarrhea: survey among pediatricians from a children's hospital in the Autonomous City of Buenos Aires. / Manejo ambulatorio de la diarrea aguda infantil: encuesta a pediatras de un hospital pediátrico de la Ciudad de Buenos Aires.

INTRODUCTION: The management of acute diarrhea is based on preventing dehydration and reducing disease duration and severity. , Ángela Gentilea INTRODUCTION The study objective was to establish the patterns for the outpatient management of acute diarrhea in children younger than 5 years. METHODS: Observational, analytical study using a self-administered survey among pediatricians from a children's hospital in the Autonomous City of Buenos Aires.Age, sex, place of work, bibliographic sources, indication of drug and non-drug therapies, and preventive and hygiene measures were recorded. The association between drug prescription and the characteristics of surveyed pediatricians was assessed. RESULTS: In total, 182/216 pediatricians completed the survey. Their mean age was 42.4 ± 10.24 years; 78.6% were females; 59.2% worked in the public sector; 22.4% worked in the emergency department; and 91.2% consulted guidelines and/or consensuses. Also, 92.9% prescribed oral rehydration solutions; 46.2%, antiemetics; 43.4%, antacids and/or gastric protectors; 35.7%, probiotics; and 30.7%, zinc. Early food reintroduction was indicated by 91.7%; breastfeeding, by 96.7%; and preventive and hygiene measures, by 96-100%. The multivariate analysis showed an association between age > 40 years and prescribing antacids/ gastric protectors (odds ratio [OR]: 2.6; 1.22-5.61), probiotics (OR: 3.03; 1.34-6.83), and zinc (OR: 0.39; 0.17-0.87); between working in the private sector and prescribing probiotics (OR: 3.05; 1.565.94); and between working in the emergency department and prescribing antacids/gastric protectors (OR: 2.60; 1.22-5.54). CONCLUSIONS: Treatment was mainly based on hydration, early food reintroduction, and breastfeeding. Age and work sector affected the prescription pattern.

Introducción. El tratamiento de la diarrea aguda se basa en prevenir la deshidratación, reducir la duración y gravedad de la enfermedad. El objetivo fue conocer los patrones de tratamiento ambulatorio de la diarrea aguda en<5 años. , Anabella C. Pacchiottia,b , Cómo citar: Castelllano VE, Giglio ND, Pacchiotti AC, Gentile Á. Manejo ambulatorio de la diarrea aguda infantil: encuesta a pediatras de un hospital pediátrico de la Ciudad de Buenos Aires. Arch Argent Pediatr 2022;120(1):46-53. a. División Promoción y Protección de la Salud, Área Epidemiología. b. Departamento de Urgencia. Hospital de Niños Dr. Ricardo Gutiérrez, Ciudad Autónoma de Buenos Aires, Argentina. Correspondencia: Vanesa E. Castellano: vane0108@hotmail.com Financiamiento: Este estudio recibió colaboración irrestricta del laboratorio Sanofi Aventis, utilizada para el material de las encuestas, equipamiento informático y una beca educacional para la Dra. Anabella Pacchiotti. Conflicto de intereses: V. Castellano, N. Giglio y Á. Gentile han participado como disertantes de conferencias auspiciadas por el laboratorio Sanofi Aventis en congresos y jornadas. Recibido: 11-5-2021 Aceptado: 15-9-2021 Métodos. Estudio observacional, analítico, mediante encuestas autoadministradas a pediatras de un hospital de niños de la Ciudad Autónoma de Buenos Aires. Se indagó: edad, sexo, lugar de trabajo, fuentes bibliográficas, indicación de tratamientos farmacológicos, no farmacológicos y medidas de prevención e higiene. Se evaluó la asociación entre prescripciones farmacológicas y características de los encuestados. Resultados. Respondieron 182/216 pediatras; la edad media fue 42,4 ± 10,24 años (el 78,6 %, mujeres); el 59,2 %, del sector público; el 22,4 %, de servicios de guardia. El 91,2 % consultaba guías/consensos. El 92,9 % prescribió fórmulas de rehidratación oral; el 46,2 %, antieméticos; el 43,4 %, antiácidos y/o protectores gástricos; el 35,7 %, probióticos, y el 30,7 %, cinc. El 91,7 % indicó realimentación precoz; el 96,7 %, lactancia materna y el 96-100 %, medidas de prevención e higiene. En el análisis multivariado, tener >40 años se asoció con prescribir antiácidos/protectores gástricos (odds ratio [OR] 2,6; 1,22-5,61), probióticos (OR 3,03; 1,34-6,83) y cinc (OR 0,39; 0,17-0,87); trabajar en el sector privado con prescribir probióticos (OR 3,05; 1,56-5,94) y en servicios de guardia, con prescribir antiácidos/ protectores gástricos (OR 2,60; 1,22-5,54). Conclusiones. El tratamiento se basó principalmente en hidratación, alimentación precoz y lactancia. La edad y el lugar de desempeño de los pediatras modifican el patrón de prescripción.

Impact of varicella vaccination in Argentina: Seroprevalence in children and adults in a pediatric hospital.

BACKGROUND: Varicella is the primary infection caused by varicella-zoster virus (VZV). In Argentina, the varicella vaccine was introduced in the National Immunization Programme in 2015 as a single dose scheduled at 15 months of age. OBJECTIVES: To estimate VZV seroprevalence in a healthy hospital based population before and after vaccine introduction to the NIP. MATERIAL Y METHODS: Cross-sectional, observational, analytic study. Healthy subjects 1-40 years of age were included between June and December 2019 and tested for VZV-antibodies. Results were compared to data from a similar prevaccination study. RESULTS: Out of 599 samples, 11 indeterminate results were excluded, 424 were positive; overall seroprevalence rate was 72.1% (95 %CI = 68,3-75,8%). No differences were observed between pre and post vaccination studies for overall prevalence or between age groups, except for vaccinated children aged 11-15 (p = 0,005). Rates increased in both periods in subjects aged 6 years or older. Primary vaccine failures were 21%; in subjects <5 years 83% seropositive cases had been vaccinated, in >5 year-olds >90% seropositive cases were associated with a history of infection (OR: 10,4; IC95%: 6,4-16,8; p < 0,001) or household contact (OR:4,8; IC95%: 3,1-7,6; p < 0,001). Vaccination protected against disease (OR: 0.25; 95 %CI: 0.09-0.68; p = 0.004). CONCLUSION: seroprevalence was high in all age groups except in unvaccinated 12 to 15-month infants. Seropositivity was due to vaccination in 15 months to 5 year-old children and to infection in older children.

Trends in Varicella Burden of Disease Following Introduction of Routine Childhood Varicella Vaccination in Argentina: A 12-Year Time Series Analysis.

One-dose universal varicella vaccination (UVV) was introduced in the Argentinian National Immunization Program in July 2015. This study examined the impact of one-dose UVV on varicella incidence and mortality in Argentina. Incidence and mortality data were obtained from official databases for pre-UVV (January 2008-June 2015) and post-UVV (July 2015-December 2019) periods. Time series analyses with autoregressive integrated moving average (ARIMA) modeling predicted varicella incidence and mortality in absence of UVV in the target (aged 1-4 years) and overall population. Predicted and observed values post-UVV were compared to estimate UVV impact. Mean annual incidence rates per 100,000 reduced from 1999 (pre-UVV) to 1122 (post-UVV) in the target population and from 178 to 154 in the overall population. Significant declines in incidence were observed, reaching reductions of 83.9% (95% prediction interval [PI]: 58.9, 90.0) and 69.1% (95% PI: 23.6, 80.7) in the target and overall populations, respectively, during peak months (September-November) post-UVV. Decreasing trends in mortality rate from 0.4 to 0.2 per 1,000,000 population were observed. Over the last four years, one-dose UVV has significantly reduced varicella burden of disease in Argentina. Continuous efforts to improve vaccination coverage rates and long-term follow-up are needed to better understand the benefits of the UVV program.

Vaccinating Children against SARS-CoV-2: A Literature Review and Survey of International Experts to Assess Safety, Efficacy and Perceptions of Vaccine Use in Children.

Introduction: The balance of risks and benefits of COVID-19 vaccination in children is more complex than in adults with limited paediatric data resulting in no global consensus on whether all healthy children should be vaccinated. We sought to assess the safety, efficacy, and effectiveness of childhood vaccination against SARS-CoV-2, as well as better understanding perceptions of vaccination in parents and vaccine experts. Methods: We performed a literature review for COVID-19 vaccine safety, efficacy, effectiveness, and perceptions. We searched international safety databases for safety data and developed an electronic survey to elicit country-specific COVID-19 immunisation data, including vaccine regulations, policies, rates, and public attitudes solicited from vaccine experts. Results: Nine studies were included in the final safety analysis. Local reactions were frequently reported across all studies and vaccine types. Adverse events reported to surveillance systems tended to be non-serious, and commonly included injection site reactions and dizziness. Twenty-three studies reported immunogenicity, efficacy, and effectiveness data. There were nine randomised control trials of six different vaccine types, which showed seroconversion of neutralising antibodies in vaccinated children ranging from 88% to 100%. The vaccine efficacy for Pfizer and Moderna vaccines ranged from 88% to 100%. There were 118 survey responses representing 55 different countries. Reported vaccination rates ranged from <1% to 98%. Most respondents described "mixed opinions" regarding paediatric vaccination policies in their country. By region, a more positive public attitude towards vaccination correlated with higher vaccination rates. Discussion: In this mixed-methods review, we have found evidence that vaccination against COVID-19 in children is safe, efficacious, and effective. Overall, the combined evidence from both the literature review and survey highlights the need for further data on both the safety and effectiveness of COVID-19 vaccinations in children.

Cost-Effectiveness Analysis of Cell Versus Egg-Based Seasonal Influenza Vaccination in Children and Adults in Argentina.

Background: Quadrivalent cell-based influenza vaccines (QIVc) avoid egg-adaptive mutations and can be more effective than traditional quadrivalent egg-based influenza vaccines (QIVe). This analysis compared the cost-effectiveness of QIVc and QIVe in Argentinian populations < 65 years old from the payer and societal perspectives. Methods: A static decision tree model compared the costs and health benefits of vaccination with QIVc vs. QIVe using a one-year time horizon. The relative vaccine effectiveness of QIVc vs. QIVe was assumed to be 8.1% for children and 11.4% for adults. An alternative high egg-adaptation scenario was also assessed. Model inputs were sourced from Argentina or the international literature. Deterministic and probabilistic sensitivity analyses were performed. Results: Compared to QIVe, QIVc would prevent 17,857 general practitioner visits, 2418 complications, 816 hospitalizations, and 12 deaths per year. From the payers' perspective, the incremental cost-effectiveness ratio per quality-adjusted life years gained was USD12,214 in the base case and USD2311 in the high egg-adaptation scenario. QIVc was cost-saving from the societal perspective in both scenarios. Conclusions: QIVc in Argentina would be cost-effective relative to QIVe. The potential health benefits and savings would be even higher in high egg-adaptation seasons.

Cost-Effectiveness Analysis of Switching from Trivalent to Quadrivalent Seasonal Influenza Vaccine in Argentina.

The burden of seasonal influenza disease in Argentina is considerable. The cost-effectiveness of trivalent (TIV) versus quadrivalent influenza vaccine (QIV) in Argentina was assessed. An age-stratified, static, decision-tree model compared the costs and benefits of vaccination for an average influenza season. Main outcomes included: numbers of influenza cases; general practitioner (GP) visits; complicated ambulatory cases; hospitalizations; deaths averted; and costs per quality-adjusted life years (QALYs) gained. Epidemiological data from Argentina for 2014-2019 were used to determine the proportion of A and B strain cases, and the frequency of mismatch between vaccine and circulating B strains. To manage uncertainty, one-way and probabilistic sensitivity analyses were performed. Switching from TIV to QIV would prevent 19,128 influenza cases, 16,164 GP visits, 2440 complicated ambulatory cases, 524 hospitalizations, and 82 deaths. Incremental cost-effectiveness ratios (ICERs) per QALY were 13,590 and 11,678 USD from the payer's and societal perspectives, respectively. The greatest health benefits and direct medical cost savings would occur in ≥ 65-year-olds. One-way sensitivity analyses demonstrated the principal drivers of ICER to be vaccine acquisition costs, environmental B strain predominance, and B strain mismatch. Introducing QIV in Argentina would be beneficial and cost-effective relative to TIV, particularly in older adults.

[Vaccination in children under 1 year with pertussis component in the context of the global initiative for the eradication of poliomyelitis in Argentina: economic analysis]. / Análisis económico de las vacunas del primer año de vida con componente pertussis en el contexto de la ini-ciativa mundial de erradicación de la poliomielitis en Argentina.

BACKGROUND: Global Polio Eradication Initiative promotes the introduction of inactivated polio vaccine (IPV) in its programs, with withdrawal of Sabin (bOPV). There is no an economic analysis of the investment related to the incorporation of IPV vaccines together with a whole cell Bordetella pertussis vaccine or combined with acellular hexavalent. AIM: An economic model that compares different vaccination schemes for the prevention of polio and pertussis in the first year of life was carried out. METHODS: Four vaccination scenarios for the primary scheme based on Argentina demographic and costs data were developed: - Scenario 1 (base case): two doses of IPV, one dose of bOPV and three doses of pentavalent (DTwP-HepB-Hib) vaccine; - Scenario 2: three doses of IPV plus three doses of pentavalent; - Scenario 3: three doses of hexavalent; - Scenario 4: two doses of hexavalent plus one dose of pentavalent plus IPV. RESULTS: The incremental cost based on scenario 1 was USD 3.716.671; 19.696.668 and 14.383.341 for scenarios 2, 3 and 4 respectively. In terms of reactogenicity savings was -14.178.240 compared base case with scenario 3. DISCUSSION: Full IPV introduction investment and costs associated were modified according to the type of vaccine and reactogenicity related with the B. pertussis component.

Vaccine hesitancy in Argentina: Validation of WHO scale for parents.

BACKGROUND: The WHO SAGE Working Group on Vaccine Hesitancy developed the Vaccine Hesitancy Scale (VHS) to identify and compare hesitancy in different global settings. The objectives of the study were to describe and analyze vaccine hesitancy and to validate the VHS in a group of parents in Buenos Aires city, Argentina. METHODS: A cross-sectional survey was conducted in parents of 1-3 and 12-15 year-old children at three health centres in Buenos Aires City, between June 2018 and May 2019. Sociodemographic data were collected together with history of refusal and/or delay in children's vaccination (defined as hesitancy). The 10-item VHS using 5-point Likert-scale (higher scores indicating lower hesitancy) was administered and children's immunization record cards were verified. Link between hesitancy and socio-demographic variables, and hesitancy and vaccination status was analyzed for five specific vaccines. Cronbach's α was used to determine internal consistency reliability and factor analysis to confirm survey subdomains. Simple and multiple regression analysis was used to examine associations between VHS scores and hesitancy, and VHS scores and vaccination status. RESULTS: Six hundred parents were surveyed and 469 immunization cards verified; 11.5% (n = 69) parents were hesitant. High maternal educational level showed significant association with hesitancy (OR 2.66 95% CI: 1.20-5.9) in the adjusted model. Hesitancy was significantly associated with incomplete MMR vaccination in children (OR 4.43 95% CI: 1.08-8.20) and HPV vaccination in adolescents (OR 3.75 95% CI: 1.54-9.12). Cronbach's α was 0.66 and factor analysis identified three underlying constructs: "Benefits", "Harms" and "Confidence in healthcare system". High scores in VHS were associated with lack of hesitancy (OR 1.2 95% CI: 1.13-1.27) and complete vaccination status (OR 1.07 95% CI: 1.02-1.12). CONCLUSIONS: Hesitancy was associated with high maternal educational level, and incomplete MMR and HPV immunization status in children and adolescents. VHS was a reliable and valid tool in this population.

Impact of varicella vaccine on nosocomial outbreaks and management of post exposure prophylaxis following in a paediatric hospital.

INTRODUCTION: In 2015, varicella vaccine was introduced to the National Immunization Programme in a one-dose regimen for infants aged 15 months. The aim of this study was to describe and compare the epidemiologic characteristics, management strategies and costs of varicella outbreaks in Ricardo Gutierrez Children's Hospital (HNRG) from 2000 to 2019, before (PreV period) and after (PostV period) the introduction of the varicella vaccine. METHODS: A retrospective, analytic study of the impact of nosocomial varicella outbreaks at the HNRG, based on active epidemiologic surveillance. We compared nosocomial varicella outbreaks rates (per 10,000 discharges) between PreV and PostV, excluding the intervention year (2015). RESULTS: During PreV, an average of 15.87 (13.91-18.02) outbreaks per year was observed and in PostV 5.5 per year (3.44-8.32). Outbreaks adjusted by all cause discharges showed a reduction of 59.13% (-36.68%, -73.62%) after vaccine introduction. Considering that in PreV the average of susceptible cases per outbreak was 5.0 and in PostV 7.8, with a cost per susceptible of AR$ $6,522 (80.27 USD) PreV and 6,708 PostV the economic impact on the reduction of outbreaks after the introduction of the vaccine, showed an estimated average savings per year of AR$ -252,128 AR$ (-3,103.11 USD). CONCLUSIONS: The number of annual varicella hospital outbreaks at the HNRG decreased significantly after varicella vaccine was introduced to NIP in Argentina with a relevant reduction in terms of costs.

[Cost-effectiveness of universal pneumococcal vaccination in Uruguay]. / Costo-efectividad de la vacunación universal antineumocócica en Uruguay.

OBJECTIVE: Evaluate the cost-effectiveness ratio of the program for universal vaccination with heptavalent pneumococcal conjugate vaccine (PCV7) in children under 5 years of age in Uruguay. METHODS: A Markov model was developed that simulated a cohort of 48 000 children born in 2007 and their progress to age 76. The baseline case used a regimen of three doses with estimated protection for five years. The presumption of vaccine efficacy and effectiveness was based on studies conducted in the United States with adjustment for serotype prevalence-incidence in Uruguay. The results were expressed as the incremental cost per life year gained (LYG) and quality-adjusted life year (QALY) [gained]. RESULTS: For the baseline case, the incremental cost was US $7334.60 for each LYG and US $4655.80 for each QALY. Eight deaths and 4 882 cases of otitis, 56 cases of bacteremia-sepsis, 429 cases of pneumonia, and 7 cases of meningitis were prevented. The model shows sensitivity to variations in vaccine cost, efficacy, and pneumonia-related mortality. CONCLUSIONS: The universal vaccination program with PCV7 in Uruguay is highly cost-effective. Therefore, it is recommended for other countries with burden of pneumococcal disease and serotype coverage similar to those of Uruguay.

Forecasting the effect of social distancing on COVID-19 autumn-winter outbreak in the metropolitan area of Buenos Aires.

Forecasting the extent of the domestic health risk of epidemics by mathematical modeling is a useful tool for evaluating the feasibility of policies for controlling outbreaks. The objective of this study was to develop a time-dependent dynamic simulation model to forecast the COVID-19 autumn-winter outbreak in the metropolitan area of Buenos Aires, and to assess the effect of social distancing on epidemic spread. The model used was the "Susceptible-Exposed-Infectious-Recovered" framework which incorporated appropriate compartments relevant to interventions such as quarantine, isolation and treatment. In a low-intervention scenario including only 2-week isolation for international travelers and their contacts, the model estimated a maximum peak of nearly 90 000 symptomatic cases for early May. For an intervention scenario with mandatory quarantine during a 5-month period, the curve of cases flattened and receded as the proportion of quarantined individuals increased. The maximum peak was expected to appear between May 8 and Jul 8 depending on the quarantine strategy, and the average number of infectious symptomatic cases were 46 840, 30 494, 23 164, 16 179, and 13 196 when 10%, 20%, 30%, 40%, and 50% of the population remained in a 5-month-term continuous quarantine, respectively. Only mandatory quarantine was able to delay the maximum peak of infection and significantly reduce the total number of infected individuals and deaths at a 150-day term. The interruption of the quarantine before 120 days of its beginning could generate an even more serious outbreak 30 days later, and surpass the scarce medical resources available for the intensive care of critically-ill patients.

La estimación mediante modelos matemáticos del efecto de una epidemia sobre la salud pública constituye una herramienta útil para evaluar la viabilidad de las políticas tendientes a controlar el brote. El objetivo de este estudio fue desarrollar un modelo de simulación dinámica dependiente del tiempo para pronosticar el brote de otoño-invierno de COVID-19 en el área metropolitana de Buenos Aires y evaluar el efecto del distanciamiento social en la propagación de la epidemia. El modelo utilizado fue el de "Susceptible-Expuesto-Infeccioso-Recuperado" que incorporó compartimentos para evaluar posibles intervenciones tales como cuarentena, aislamiento y tratamiento. En un escenario de baja intervención que incluye solo 2 semanas de aislamiento para viajeros internacionales y sus contactos, el modelo estimó un pico máximo de casi 90 000 casos sintomáticos para principios de mayo. Para un escenario de intervención con cuarentena obligatoria durante un período de 5 meses, la curva de casos se aplanó y se alejó a medida que aumentaba la proporción de individuos en cuarentena. Se constató que el pico máximo aparecía entre el 8 de mayo y el 8 de julio, según la estrategia de cuarentena, y el número promedio de casos sintomáticos infecciosos fue 46 840, 30 494, 23 164, 16 179 y 13 196 cuando el 10%, 20%, 30%, 40% y 50% de la población permaneció en una cuarentena continua de 5 meses, respectivamente. Solo la cuarentena obligatoria fue capaz de retrasar el pico máximo de infección y reducir significativamente el número total de individuos infectados y muertes en un plazo de 150 días. La interrupción de la cuarentena antes de los 120 días de su inicio podría generar un brote aún más grave 30 días después y sobrepasar los escasos recursos médicos disponibles para el cuidado intensivo de pacientes críticos.

Cost-effectiveness of introducing an MF59-adjuvanted trivalent influenza vaccine for older adults in Argentina.

INTRODUCTION: Influenza surveillance in Argentina reported influenza-like illness at a rate of 3500/100,000, a hospitalization rate of 15.5/100,000, and a death rate of 0.32/100,000 annually in adults aged over 65 years. The high burden of disease may be due to a combination of immunosenescence and the suboptimal clinical effectiveness of conventional, non-adjuvanted influenza vaccines in this age group. There is a clinical need for more effective influenza vaccines in this population. This study evaluated the cost-effectiveness of an MF59®-adjuvanted trivalent influenza vaccine (aTIV) in adults aged over 65 years in Argentina compared with the non-adjuvanted trivalent influenza vaccine (TIV) used under the current national vaccination policy. METHODS: A decision tree cost-effectiveness model was developed to estimate the cost-effectiveness of switching from TIV to aTIV in Argentinian older adults. The model compared cost and health benefits of vaccination in one influenza season from the payer perspective. The main predictions included survival, quality-adjusted survival, and costs. Model inputs were sourced from Argentina or internationally where local data was considered inaccurate. Vaccine efficacy assumptions were extracted from recently published, peer-reviewed scientific literature. RESULTS: Switching from TIV to aTIV would result in 170 deaths averted and 1310 incremental quality-adjusted life years (QALYs) gained. The incremental cost-effectiveness ratio per QALY was US $2660.59 from the payer perspective. In all sensitivity analyses, aTIV remained highly cost-effective. The probabilistic sensitivity analyses showed a 95% CI per QALY of US $113.74-7721.67. CONCLUSION: Introducing an adjuvanted influenza vaccine in Argentina is potentially beneficial and cost-effective relative to the currently-used TIV through the reduction of disease burden and utilization of healthcare resources.