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1.
Vaccines ; 10(4):608, 2022.
Article in English | MDPI | ID: covidwho-1786113

ABSTRACT

Currently available vaccines against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) are highly effective but not able to keep the coronavirus disease 2019 (COVID-19) pandemic completely under control. Alternative R&D strategies are required to induce a long-lasting immunological response and to reduce adverse events as well as to favor rapid development and large-scale production. Several technological platforms have been used to develop COVID-19 vaccines, including inactivated viruses, recombinant proteins, DNA- and RNA-based vaccines, virus-vectored vaccines, and virus-like particles. In general, mRNA vaccines, protein-based vaccines, and vectored vaccines have shown a high level of protection against COVID-19. However, the mutation-prone nature of the spike (S) protein affects long-lasting vaccine protection and its effectiveness, and vaccinated people can become infected with new variants, also showing high virus levels. In addition, adverse effects may occur, some of them related to the interaction of the S protein with the angiotensin-converting enzyme 2 (ACE-2). Thus, there are some concerns that need to be addressed and challenges regarding logistic problems, such as strict storage at low temperatures for some vaccines. In this review, we discuss the limits of vaccines developed against COVID-19 and possible innovative approaches.

2.
Expert Rev Vaccines ; : 1-8, 2022 Apr 15.
Article in English | MEDLINE | ID: covidwho-1778823

ABSTRACT

BACKGROUND: Consolidated information on the effectiveness of COVID-19 booster vaccination in Europe are scarce. RESEARCH DESIGN AND METHODS: We assessed the effectiveness of a booster dose of an mRNA vaccine against any SARS-CoV-2 infection (symptomatic or asymptomatic) and severe COVID-19 (hospitalization or death) after over two months from administration among priority target groups (n = 18,524,568) during predominant circulation of the Delta variant in Italy (July-December 2021). RESULTS: Vaccine effectiveness (VE) against SARS-CoV-2 infection and, to a lesser extent, against severe COVID-19, among people ≥60 years and other high-risk groups (i.e. healthcare workers, residents in long-term-care facilities, and persons with comorbidities or immunocompromised), peaked in the time-interval 3-13 weeks (VE against infection = 67.2%, 95% confidence interval (CI): 62.5-71.3; VE against severe disease = 89.5%, 95% CI: 86.1-92.0) and then declined, waning 26 weeks after full primary vaccination (VE against infection = 12.2%, 95% CI: -4.7-26.4; VE against severe disease = 65.3%, 95% CI: 50.3-75.8). After 3-10 weeks from the administration of a booster dose, VE against infection and severe disease increased to 76.1% (95% CI: 70.4-80.7) and 93.0% (95% CI: 90.2-95.0), respectively. CONCLUSIONS: These results support the ongoing vaccination campaign in Italy, where the administration of a booster dose four months after completion of primary vaccination is recommended.

3.
BMJ ; 376: e069052, 2022 02 10.
Article in English | MEDLINE | ID: covidwho-1759321

ABSTRACT

OBJECTIVES: To estimate the effectiveness of mRNA vaccines against SARS-CoV-2 infection and severe covid-19 at different time after vaccination. DESIGN: Retrospective cohort study. SETTING: Italy, 27 December 2020 to 7 November 2021. PARTICIPANTS: 33 250 344 people aged ≥16 years who received a first dose of BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna) vaccine and did not have a previous diagnosis of SARS-CoV-2 infection. MAIN OUTCOME MEASURES: SARS-CoV-2 infection and severe covid-19 (admission to hospital or death). Data were divided by weekly time intervals after vaccination. Incidence rate ratios at different time intervals were estimated by multilevel negative binomial models with robust variance estimator. Sex, age group, brand of vaccine, priority risk category, and regional weekly incidence in the general population were included as covariates. Geographic region was included as a random effect. Adjusted vaccine effectiveness was calculated as (1-IRR)×100, where IRR=incidence rate ratio, with the time interval 0-14 days after the first dose of vaccine as the reference. RESULTS: During the epidemic phase when the delta variant was the predominant strain of the SARS-CoV-2 virus, vaccine effectiveness against SARS-CoV-2 infection significantly decreased (P<0.001) from 82% (95% confidence interval 80% to 84%) at 3-4 weeks after the second dose of vaccine to 33% (27% to 39%) at 27-30 weeks after the second dose. In the same time intervals, vaccine effectiveness against severe covid-19 also decreased (P<0.001), although to a lesser extent, from 96% (95% to 97%) to 80% (76% to 83%). High risk people (vaccine effectiveness -6%, -28% to 12%), those aged ≥80 years (11%, -15% to 31%), and those aged 60-79 years (2%, -11% to 14%) did not seem to be protected against infection at 27-30 weeks after the second dose of vaccine. CONCLUSIONS: The results support the vaccination campaigns targeting high risk people, those aged ≥60 years, and healthcare workers to receive a booster dose of vaccine six months after the primary vaccination cycle. The results also suggest that timing the booster dose earlier than six months after the primary vaccination cycle and extending the offer of the booster dose to the wider eligible population might be warranted.


Subject(s)
/immunology , COVID-19/epidemiology , Immunization, Secondary/statistics & numerical data , SARS-CoV-2/pathogenicity , /administration & dosage , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19/diagnosis , COVID-19/immunology , COVID-19/prevention & control , Female , Follow-Up Studies , Humans , Immunogenicity, Vaccine , Incidence , Italy/epidemiology , Male , Middle Aged , SARS-CoV-2/isolation & purification , Severity of Illness Index , Time Factors , Treatment Outcome , Vaccination/statistics & numerical data , Young Adult
4.
J Community Health ; 2022 Mar 25.
Article in English | MEDLINE | ID: covidwho-1756842

ABSTRACT

This study describes a SARS-CoV-2 outbreak caused by the Delta (B.1.617.2) variant in a nursing home in Central Italy during October-November 2021. Trained interviewers collected data from residents, staff, and administration officers with an agreed informed consent procedure. Thirty-two (44.5%) out of 72 residents (median age 89 years) and six (26.1%) of 23 healthcare workers were found to be infected with SARS-CoV-2. Infections occurred more often among residents with a higher index of independence in daily living activities, suggesting an increased risk for those with more interactions. Twenty-five infected residents (78.1%) received the booster dose of mRNA anti-COVID-19 vaccine > 7 days before SARS-CoV-2 onset. Half of the infected residents had mild symptoms, and only three required hospitalisation, one of whom died from COVID-19 complications. The study underlines the effectiveness of a booster dose in providing a high protection against severe disease and hospitalisation even among vulnerable individuals infected with the Delta variant of concern.

5.
Annali dell'Istituto Superiore di Sanita ; 58(1):1-5, 2022.
Article in English | ProQuest Central | ID: covidwho-1738008

ABSTRACT

Introduction. Multiple variants of SARS-CoV-2, since the end of 2020 have emerged in many geographical areas and are currently under surveillance worldwide highlighting the continuing need for genomic monitoring to detect variants previously not yet identified. Methods. In this study, we used whole-genome sequencing (WGS) and phylogenetic analysis to investigate A.27 lineage SARS-CoV-2 from Sardinia, Italy. Results. The Italian A.27 lineage genomes from Sardinia appeared related in a clade with genomes from France. Among the key mutations identified in the spike protein, the N501Y and the L452R deserve attention as considered likely vaccine escape mutations. Additional mutations were also here reported. Conclusion. A combination of features could explain our data such as SARS-CoV-2 genetic variability, viral dynamics, the human genetic diversity of Sardinian populations, the island context probably subjected to different selective pressures. Molecular and genomic investigation is essential to promptly identify variants with specific mutations with potential impact on public health and vaccine formulation.

6.
Viruses ; 14(3)2022 02 25.
Article in English | MEDLINE | ID: covidwho-1737036

ABSTRACT

We performed next-generation sequencing (NGS), phylogenetic analysis, gene flows, and N- and O-glycosylation prediction on SARS-CoV-2 genomes collected from lab-confirmed cases from different Italian regions. To this end, a total of 111 SARS-CoV-2 genomes collected in Italy between 29 January and 27 March 2020 were investigated. The majority of the genomes belonged to lineage B.1, with some descendant lineages. The gene flow analysis showed that the spread occurred mainly from the north to the center and to the south of Italy, as confirmed by epidemiological data. The mean evolutionary rate estimated here was 8.731 × 10-4 (95% highest posterior density, HPD intervals 5.809 × 10-4 to 1.19 × 10-3), in line with values reported by other authors. The dated phylogeny suggested that SARS-CoV-2 lineage B.1 probably entered Italy between the end of January and early February 2020. Continuous molecular surveillance is needed to trace virus circulation and evolution.


Subject(s)
COVID-19 , Genome, Viral , COVID-19/epidemiology , Genomics , Humans , Phylogeny , SARS-CoV-2/genetics
7.
Euro Surveill ; 27(5)2022 02.
Article in English | MEDLINE | ID: covidwho-1700766

ABSTRACT

BackgroundSeveral SARS-CoV-2 variants of concern (VOC) have emerged through 2020 and 2021. There is need for tools to estimate the relative transmissibility of emerging variants of SARS-CoV-2 with respect to circulating strains.AimWe aimed to assess the prevalence of co-circulating VOC in Italy and estimate their relative transmissibility.MethodsWe conducted two genomic surveillance surveys on 18 February and 18 March 2021 across the whole Italian territory covering 3,243 clinical samples and developed a mathematical model that describes the dynamics of co-circulating strains.ResultsThe Alpha variant was already dominant on 18 February in a majority of regions/autonomous provinces (national prevalence: 54%) and almost completely replaced historical lineages by 18 March (dominant across Italy, national prevalence: 86%). We found a substantial proportion of the Gamma variant on 18 February, almost exclusively in central Italy (prevalence: 19%), which remained similar on 18 March. Nationally, the mean relative transmissibility of Alpha ranged at 1.55-1.57 times the level of historical lineages (95% CrI: 1.45-1.66). The relative transmissibility of Gamma varied according to the assumed degree of cross-protection from infection with other lineages and ranged from 1.12 (95% CrI: 1.03-1.23) with complete immune evasion to 1.39 (95% CrI: 1.26-1.56) for complete cross-protection.ConclusionWe assessed the relative advantage of competing viral strains, using a mathematical model assuming different degrees of cross-protection. We found substantial co-circulation of Alpha and Gamma in Italy. Gamma was not able to outcompete Alpha, probably because of its lower transmissibility.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Italy/epidemiology , Models, Theoretical
8.
Bulletin of the World Health Organization ; 100(2):161-167, 2022.
Article in English | CINAHL | ID: covidwho-1690495

ABSTRACT

Problem After Italy's first national restriction measures in 2020, a robust approach was needed to monitor the emerging epidemic of coronavirus disease 2019 (COVID-19) at subnational level and provide data to inform the strengthening or easing of epidemic control measures. Approach We adapted the European Centre for Disease Prevention and Control rapid risk assessment tool by including quantitative and qualitative indicators from existing national surveillance systems. We defined COVID-19 risk as a combination of the probability of uncontrolled transmission of severe acute respiratory syndrome coronavirus 2 and of an unsustainable impact of COVID-19 cases on hospital services, adjusted in relation to the health system's resilience. The monitoring system was implemented with no additional cost in May 2020. Local setting The infectious diseases surveillance system in Italy uses consistent data collection methods across the country's decentralized regions and autonomous provinces. Relevant changes Weekly risk assessments using this approach were sustainable in monitoring the epidemic at regional level from 4 May 2020 to 24 September 2021. The tool provided reliable assessments of when and where a rapid increase in demand for health-care services would occur if control or mitigation measures were not increased in the following 3 weeks. Lessons learnt Although the system worked well, framing the risk assessment tool in a legal decree hampered its flexibility, as indicators could not be changed without changing the law. The relative complexity of the tool, the impossibility of real-time validation and its use for the definition of restrictions posed communication challenges. Situación Tras las primeras medidas nacionales de restricción en Italia en 2020, se necesitaba un enfoque sólido para supervisar la epidemia emergente de la coronavirosis de 2019 (COVID-19) a nivel subnacional y proporcionar datos que informaran sobre el refuerzo o la flexibilización de las medidas de contención de la epidemia. Enfoque Se adaptó la herramienta de valoración rápida de riesgos del Centro Europeo para la Prevención y el Control de las Enfermedades, al incluir indicadores cuantitativos y cualitativos de los sistemas nacionales de vigilancia existentes. Se definió el riesgo de la COVID-19 como una combinación de la probabilidad de transmisión descontrolada del coronavirus del síndrome respiratorio agudo grave de tipo 2 y de un efecto no sostenible de los casos de la COVID-19 en los servicios hospitalarios, y se ajustó en relación con la capacidad de recuperación del sistema sanitario. El sistema de supervisión se aplicó sin costes adicionales en mayo de 2020. Marco regional El sistema de vigilancia de las enfermedades infecciosas en Italia aplica métodos de recopilación de datos coherentes en todas las regiones y provincias autónomas descentralizadas del país. Cambios importantes Las valoraciones semanales de los riesgos mediante este enfoque fueron sostenibles en la supervisión de la epidemia a nivel regional entre el 4 de mayo de 2020 y el 24 de septiembre de 2021. La herramienta proporcionó valoraciones fiables de cuándo y dónde se produciría un rápido aumento de la demanda de servicios sanitarios si no se incrementaban las medidas de contención o mitigación en las tres semanas siguientes. Lecciones aprendidas Aunque el sistema funcionó bien, el hecho de enmarcar la herramienta de valoración de los riesgos en un decreto legal dificultó su flexibilidad, ya que los indicadores no se podían modificar sin cambiar la ley. La relativa complejidad de la herramienta, la imposibilidad de validación en tiempo real y su uso para la definición de las restricciones plantearon problemas de comunicación. Problème Après avoir pris ses premières mesures de restriction nationales en 2020, l'Italie avait besoin d'une approche solide pour surveiller l'épidémie naissante de maladie à coronavirus 2019 (COVID-19) au niveau régional, et fournir les données permettant de renforcer ou d'alléger les mesures destinées à l'endiguer. Approche Nous avons adapté l'outil d'évaluation rapide des risques du Centre européen de prévention et de contrôle des maladies en y intégrant des indicateurs quantitatifs et qualitatifs issus des systèmes de surveillance nationaux existants. Pour définir le risque lié à la COVID-19, nous avons associé la probabilité d'une transmission incontrôlée du coronavirus 2 du syndrome respiratoire aigu sévère, à l'impact immédiat des cas de COVID-19 sur les services hospitaliers, en procédant à des ajustements selon la résilience du système de soins de santé. Le dispositif de surveillance a été mis en oeuvre en mai 2020 sans entraîner de coûts supplémentaires. Environnement local En Italie, le système de surveillance des maladies infectieuses repose sur des méthodes uniformes de collecte de données dans les provinces autonomes et régions décentralisées à travers le pays. Changements significatifs Les évaluations des risques réalisées toutes les semaines avec cette approche ont permis de surveiller l'épidémie à l'échelle régionale du 4 mai 2020 au 24 septembre 2021. L'outil a identifié les dates et lieux susceptibles de connaître une augmentation rapide de la demande en services de soins de santé si aucune mesure supplémentaire de contrôle et de lutte n'était prise dans les trois semaines. Leçons tirées Bien que le système ait fonctionné, inscrire l'outil d'évaluation des risques dans un décret législatif a réduit sa flexibilité, car les indicateurs ne pouvaient être modifiés sans réformer la loi. La relative complexité de l'outil, l'impossibilité de procéder à une validation en temps réel et son usage pour imposer des restrictions ont posé des problèmes de communication. Проблема После первых национальных ограничительных мер в Италии в 2020 году потребовался активный подход для мониторинга зарождающейся эпидемии коронавирусной инфекции 2019 года (COVID-19) на субнациональном уровне и для предоставления данных для обоснования усиления или ослабления мер по борьбе с эпидемией. Подход Авторы адаптировали инструмент для оперативных оценок рисков Европейского центра по контролю и профилактике заболеваний, включив в него количественные и качественные показатели из существующих национальных систем эпиднадзора. Авторы определили риск COVID-19 как комбинацию вероятности неконтролируемой передачи тяжелого острого респираторного синдрома, вызванного коронавирусом-2, и разрушительного воздействия случаев COVID-19 на больничное обслуживание, которая скорректирована с учетом устойчивости системы здравоохранения. Система мониторинга была внедрена без каких-либо дополнительных затрат в мае 2020 года. Местные условия В системе эпиднадзора за инфекционными заболеваниями в Италии используются последовательные методы сбора данных по децентрализованным регионам и автономным провинциям страны. Осуществленные перемены Еженедельные оценки рисков с использованием данного подхода регулярно применялись при мониторинге эпидемии на региональном уровне с 4 мая 2020 года по 24 сентября 2021 года. Инструмент обеспечил надежную оценку того, когда и где может произойти быстрое увеличение спроса на медицинские услуги, если меры по борьбе или смягчению последствий не будут усилены в течение следующих 3 недель. Выводы Несмотря на то что система работала эффективно, включение инструмента для оценок рисков в юридические постановления ограничивало его гибкость, поскольку показатели не могли быть изменены без изменения закона. Относительная сложность инструмента, невозможность проверки в реальном времени и его использование для определения ограничений создают проблемы коммуникации. 问题 2020 年意大利首次实施全国性限制措施后,需要 采取可靠方法以监测新型冠状病毒肺炎 (新冠肺炎) 疫情在地方层面的蔓延情况,并提供数据以表明是否 需要加强或放松疫情控制措施。 方法 通过纳入现有国家监测系统的定量和定性指 标,我们调整了欧洲疾病预防和控制中心的快速风险 评估工具。我们将新型冠状病毒肺炎风险综合定义为 严重急性呼吸系统综合症冠状病毒 2 不受控制传播 的可能性以及新型冠状病毒肺炎病例对医院服务的非持续性影响,并根据卫生系统的顺应力进行了调整。 2020 年 5 月,在没有产生额外成本的前提下实施了监 测系统。 当地状况 意大利传染病监测系统在全国各个分散 的地区和自治省统一使用相同的数据收集方法。 相关变化 在 2020 年 5 月 4 日至 2021 年 9 月 24 日 期间,使用这种方法开展的每周风险评估在监测区域 层面疫情情况方面具有可持续性。该工具能够可靠地 评估,如果在接下来的 3 周内没有加强控制或缓解措 施,何时何地医疗保健服务需求会迅速增加。 经验教训 尽管该系统运作良好,但将风险评估工 具纳入法令范畴限制了其灵活性,因为若不更改法律, 则无法变更指标。该工具的相对复杂性、实时验证的 不可能性及其在法规限定方面的用途导致产生了沟通 挑战。

9.
Vaccine ; 40(13): 1987-1995, 2022 03 18.
Article in English | MEDLINE | ID: covidwho-1689017

ABSTRACT

National immunisation programmes require an adequate supply of vaccines to function properly but many countries, globally and in Europe, have reported vaccine shortages. A comprehensive view of vaccine shortages and stockouts in the EU/EEA is missing in the published literature. This study was conducted in the framework of the European Joint Action on Vaccination (EU-JAV). Twenty-eight countries, including 20 EU-JAV consortium member states and an additional 8 EU/EEA countries, were invited to participate in a survey aimed at collecting information on vaccine shortages and stock-outs experienced from 2016 to 2019, their main causes, actions taken, and other aspects of vaccine supply. Twenty-one countries completed the survey (response rate 75%), of which 19 reported at least one shortage/stock-out event. Overall, 115 events were reported, 28 of which led to a change in the national immunisation programme. The most frequently involved vaccines were DT- and dT-containing combination vaccines, hepatitis B, hepatitis A, and BCG vaccines. The median duration of shortages/stock-outs was five months (range <1 month-39 months). Interruption in supply and global shortage were the most frequently indicated causes. Only about half of countries reported having an immunization supply chain improvement plan. Similarly, only about half of countries had recommendations or procedures in place to address shortages/stockouts. The survey also identified the occurrence of shortages/stockouts of other biological products (e.g. diphtheria antitoxin in 12 countries). Public health strategies to assure a stable and adequate vaccine supply for immunization programmes require coordinated actions from all stakeholders, harmonized definitions, strengthening of reporting and monitoring systems, the presence of an immunization supply chain improvement plan in all countries, and procedures or recommendations in place regarding the use of alternative vaccines or vaccination schedules in case of shortages/stockouts.

10.
EuropePMC;
Preprint in English | EuropePMC | ID: ppcovidwho-327217

ABSTRACT

The SARS-CoV-2 variant of concern Omicron was first detected in Italy in November 2021. Data from three genomic surveys conducted in Italy between December 2021 and January 2022 suggest that Omicron became dominant in less than one month (prevalence on January 3: 78.6%-83.8%) with a doubling time of 2.7-3.1 days. The mean net reproduction number rose from about 1.15 in absence of Omicron to a peak of 1.83 for symptomatic cases and 1.33 for hospitalized cases, while it remained stable for critical cases.

11.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-311797

ABSTRACT

On March 10, 2020, Italy imposed a national lockdown to curtail the spread of COVID-19. Here we estimate that, fourteen days after the implementation of the strategy, the net reproduction number has dropped below the epidemic threshold - estimated range 0.4-0.7. Our findings provide a timeline of the effectiveness of the implemented lockdown, which is relevant for a large number of countries that followed Italy in enforcing similar measures.

12.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-310609

ABSTRACT

Background: On March 11 2020, the World Health Organization (WHO) declared COVID-19 outbreak a pandemic. As the mosquito season progressed, the understandable concern that such insects could transmit the virus began to spread. In response to this request, the vector competence for SARS-CoV-2 of Culex pipiens and Aedes albopictus , the two most common species of vector mosquitoes in Europe, was investigated. Due to the peculiar feeding behaviour, the role of Aedes albopictus in a potential mechanical transmission of the virus was also evaluated. MethodsFor the vector competence study, mosquitoes were allowed to take up an infectious blood meal. Mosquitoes were collected and analysed at 0, 3, 7 and 10 days post-feeding. For the mechanical transmission test Ae. albopictus females were allowed to feed for a short time on a feeder containing infectious blood and then on a feeder containing virus-free blood. Mosquitoes and blood were tested for viral presence.Results Cx. pipiens and Ae. albopictus tested resulted not competent for SARS-CoV-2 and Ae. albopictus was unable to mechanically transmit the virus. ConclusionsThis study shows that the most common species of vector mosquitoes in Europe don’t transmit SARS-CoV-2 and, for the first time, that Ae. albopictus is unable to mechanically transmit the virus by feeding from a positive host to a healthy host.

13.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-308578

ABSTRACT

In 2020, countries affected by the COVID-19 pandemic implemented various non-pharmaceutical interventions to contrast the spread of the virus and its impact on their healthcare systems and economies. Using Italian data at different geographic scales, we investigate the relationship between human mobility, which subsumes many facets of the population's response to the changing situation, and the spread of COVID-19. Leveraging mobile phone data from February through September 2020, we find a striking relationship between the decrease in mobility flows and the net reproduction number. We find that the time needed to switch off mobility and bring the net reproduction number below the critical threshold of 1 is about one week. Moreover, we observe a strong relationship between the number of days spent above such threshold before the lockdown-induced drop in mobility flows and the total number of infections per 100k inhabitants. Estimating the statistical effect of mobility flows on the net reproduction number over time, we document a 2-week lag positive association, strong in March and April, and weaker but still significant in June. Our study demonstrates the value of big mobility data to monitor the epidemic and inform control interventions during its unfolding.

14.
Children (Basel) ; 9(2)2022 Feb 12.
Article in English | MEDLINE | ID: covidwho-1686623

ABSTRACT

Data on the effective burden of the SARS-CoV-2 pandemic in the pediatric population are limited. We aimed at assessing the prevalence of SARS-CoV-2 IgG antibodies in children at three subsequent time-points. The study was conducted between January 2021 and July 2021 among children referring to the Research Institute for Maternal and Child Health "Burlo Garofolo" in Trieste, a referral regional hospital in Friuli Venezia Giulia, Italy. A multivariate analysis was conducted to assess factors independently associated with seroconversion. A total of 594 children were included. Anti-SARS-CoV-2 trimeric Spike protein IgG antibodies were found in 32 (15.4%) children tested in April-May and in 20 (11.8%) in June-July 2021, compared with 24 (11.1%) of those tested in January-February 2021 (p = 0.37, Armitage exact test for trend over time p = 0.76). A subgroup analysis and a multivariate logistic regression analysis were performed considering sociodemographic, clinical, and historical variables. Three categories of children showed statistically significant increased odds of positive anti-SARS-CoV-2 IgG antibodies: children previously positive to a nasopharyngeal swab (AdjOR 15.41, 95%CI 3.44-69.04, p < 0.001), cohabitant with a person with an history of a previous positive nasopharyngeal swab (AdjOR 9.95, 95%CI 5.35-18.52, p < 0.001), and children with a foreign citizenship (AdjOR 2.4, 95%CI 1.05-5.70, p = 0.002). The study suggests that seroprevalence studies may be of limited help in estimating the prevalence of the COVID-19 pandemic in children. Further studies are needed to identify other markers of previous SARS-CoV-2 infection in children, such as CD4+ T cells or memory B-cells.

15.
Bull World Health Organ ; 100(2): 161-167, 2022 Feb 01.
Article in English | MEDLINE | ID: covidwho-1674216

ABSTRACT

Problem: After Italy's first national restriction measures in 2020, a robust approach was needed to monitor the emerging epidemic of coronavirus disease 2019 (COVID-19) at subnational level and provide data to inform the strengthening or easing of epidemic control measures. Approach: We adapted the European Centre for Disease Prevention and Control rapid risk assessment tool by including quantitative and qualitative indicators from existing national surveillance systems. We defined COVID-19 risk as a combination of the probability of uncontrolled transmission of severe acute respiratory syndrome coronavirus 2 and of an unsustainable impact of COVID-19 cases on hospital services, adjusted in relation to the health system's resilience. The monitoring system was implemented with no additional cost in May 2020. Local setting: The infectious diseases surveillance system in Italy uses consistent data collection methods across the country's decentralized regions and autonomous provinces. Relevant changes: Weekly risk assessments using this approach were sustainable in monitoring the epidemic at regional level from 4 May 2020 to 24 September 2021. The tool provided reliable assessments of when and where a rapid increase in demand for health-care services would occur if control or mitigation measures were not increased in the following 3 weeks. Lessons learnt: Although the system worked well, framing the risk assessment tool in a legal decree hampered its flexibility, as indicators could not be changed without changing the law. The relative complexity of the tool, the impossibility of real-time validation and its use for the definition of restrictions posed communication challenges.


Subject(s)
COVID-19 , Epidemics , Humans , Italy/epidemiology , Risk Assessment , SARS-CoV-2
16.
Vaccines (Basel) ; 10(2)2022 Jan 21.
Article in English | MEDLINE | ID: covidwho-1649112

ABSTRACT

(1) Background: The objective of this study was to assess the effectiveness of SARS-CoV-2 vaccines in terms of prevention of disease and transmission in the pre-Delta era. The evaluation was narrowed to two mRNA vaccines and two modified adenovirus-vectored vaccines. (2) Methods: The overall risk of any SARS-CoV-2 infection confirmed by positive real-time Polymerase Chain Reaction (PCR) test was estimated in partially and fully vaccinated individuals. The evidence synthesis was pursued through a random-effects meta-analysis. The effect size was expressed as relative risk (RR) and RRR (RR reduction) of SARS-CoV-2 infection following vaccination. Heterogeneity was investigated through a between-study heterogeneity analysis and a subgroup meta-analysis. (3) Results: The systematic review identified 27 studies eligible for the quantitative synthesis. Partially vaccinated individuals presented a RRR = 73% (95%CI = 59-83%) for positive SARS-CoV-2 PCR (RR = 0.27) and a RRR=79% (95%CI = 30-93%) for symptomatic SARS-CoV-2 PCR (RR = 0.21). Fully vaccinated individuals showed a RRR = 94% (95%CI = 88-98%) for SARS-CoV-2 positive PCR (RR = 0.06) compared to unvaccinated individuals. The full BNT162b2 vaccination protocol achieved a RRR = 84-94% against any SARS-CoV-2-positive PCR and a RRR = 68-84% against symptomatic positive PCR. (4) Conclusions: The meta-analysis results suggest that full vaccination might block transmission. In particular, the risk of SARS-CoV-2 infection appeared higher for non-B.1.1.7 variants and individuals aged ≥69 years. Considering the high level of heterogeneity, these findings must be taken with caution. Further research on SARS-CoV-2 vaccine effectiveness against emerging SARS-CoV-2 variants is encouraged.

17.
Vaccines (Basel) ; 10(1)2022 Jan 14.
Article in English | MEDLINE | ID: covidwho-1625697

ABSTRACT

The COVID-19 pandemic has affected national healthcare systems worldwide, with around 282 million cumulative confirmed cases reported in over 220 countries and territories as of the end of 2021. The Italian National Health System was heavily affected, with detrimental impacts on preventive service delivery. Routine vaccination services were disrupted across the country during the first months of the pandemic, and both access to and demand for vaccines have decreased during the pandemic. In many cases, parents preferred to postpone scheduled appointments for routine paediatric vaccinations because of stay-at-home orders or fear of COVID-19 infection when accessing care. The objective of the current study was to assess the routine childhood vaccine coverage (VC) rates during the COVID-19 epidemic in Italy. We compared 2020 and 2019 VC by age group and vaccine type. The Italian Ministry of Health collected anonymised and aggregated immunisation national data through the local health authorities (LHAs). Results were considered statistically significant at a two-tailed p-value ≤ 0.05. VC rates for mandatory vaccinations decreased in 2020 compared to 2019 (range of VC rate decrease: -1% to -2.7%), while chicken pox increased (+2.2%) in 7-year-old children. Recommended vaccinations were moderately affected (range of VC rate decrease in 2020 vs. 2019: -1.4% to -8.5%), with the exception of anti-HPV in males, Men ACWY, and anti-rotavirus vaccination (VC increase 2020 vs. 2019: +1.8%, +4.7% and +9.4%, respectively). In the COVID-19 era, the implementation of coherent, transparent, and effective communication campaigns and educational programs on safe childhood vaccinations, together with the increase in the number of healthcare staff employed, is essential to support strategies to reinforce vaccination confidence and behaviour, thus avoiding health threats due to VPD during and beyond COVID-19 times.

18.
Ann Ist Super Sanita ; 57(4): 265-271, 2021.
Article in English | MEDLINE | ID: covidwho-1614145

ABSTRACT

INTRODUCTION: To evaluate the decline of antibodies induced by SARS-CoV-2 infection, the individuals resident in 5 municipalities of the Autonomous Province of Trento, Northern Italy, who resulted IgG positive for anti-SARS-CoV-2 nucleocapsid (NC) in May 2020, were tested four months later. METHODS: Anti-SARS-CoV-2 NC antibodies were detected using the Abbott SARS-CoV-2 IgG assay. Samples that gave a negative result were re-tested using the Liaison SARS-CoV-2 IgG assay to assess anti-spike (S) S1/S2 antibodies. The fifty-percent tissue culture infective dose (TCID50) neutralizing assay was performed on a subgroup of formerly positive sera. Statistical analysis was performed by STATA version 16.1 (STATA Corp., College Station, Texas, USA). RESULTS: Overall, 480 out of 1159 participants became seronegative for anti-NC IgG antibodies. Age above 70 years and cough were associated with persistent anti-NC IgG levels. Most anti-NC IgG negative sera were positive for anti-S IgG (77.9%). The neutralization assay showed high concordance with anti-S antibodies positivity. CONCLUSION: In conclusion, a decline of anti-NC IgG values was recorded four months after the first evaluation. A high proportion of anti-NC seronegative individuals were positive for anti-spike IgG antibodies, which appear to persist longer and to better correlate with neutralization activity.


Subject(s)
Antibodies, Neutralizing , COVID-19 , Aged , Antibodies, Viral , COVID-19 Serological Testing , Humans , SARS-CoV-2
19.
Nat Commun ; 12(1): 7272, 2021 12 14.
Article in English | MEDLINE | ID: covidwho-1574987

ABSTRACT

COVID-19 vaccination is allowing a progressive release of restrictions worldwide. Using a mathematical model, we assess the impact of vaccination in Italy since December 27, 2020 and evaluate prospects for societal reopening after emergence of the Delta variant. We estimate that by June 30, 2021, COVID-19 vaccination allowed the resumption of about half of pre-pandemic social contacts. In absence of vaccination, the same number of cases is obtained by resuming only about one third of pre-pandemic contacts, with about 12,100 (95% CI: 6,600-21,000) extra deaths (+27%; 95% CI: 15-47%). Vaccination offset the effect of the Delta variant in summer 2021. The future epidemic trend is surrounded by substantial uncertainty. Should a pediatric vaccine (for ages 5 and older) be licensed and a coverage >90% be achieved in all age classes, a return to pre-pandemic society could be envisioned. Increasing vaccination coverage will allow further reopening even in absence of a pediatric vaccine.


Subject(s)
COVID-19 Vaccines , COVID-19/prevention & control , Vaccination , Adolescent , Child , Child, Preschool , Humans , Italy , Models, Theoretical , Pandemics , SARS-CoV-2 , Vaccination Coverage
20.
2021.
Preprint in English | Other preprints | ID: ppcovidwho-295429

ABSTRACT

Vaccination campaigns against COVID-19 are allowing the progressive release of physical distancing restrictions in many countries. However, the global spread of the highly transmissible Delta variant has likely suppressed the residual chances of SARS-CoV-2 elimination through herd immunity alone. Here we assess the impact of the vaccination program in Italy since its start on December 27, 2020 and evaluate possible prospects for reopening the society while at the same time keeping COVID-19 under control. To this aim, we propose a mathematical modeling framework where levels of social activity are adjusted to match the time-series of the net reproduction number as estimated from surveillance data. We compared the estimated level of social contacts, number of deaths, and transmission potential with those of a counterfactual scenario where the same epidemic trajectory is obtained in absence of vaccination. We then evaluate the prospective impact of different scenarios of vaccination coverage and different social activity levels on SARS-CoV-2 reproduction number. We estimate that by June 30, 2021, the COVID-19 vaccination program allowed the resumption of about half the social contacts that were recorded in pre-pandemic times;in absence of vaccination, only about one third could have been resumed to obtain the same number of cases, with the added cost of about 12,100 (95%CI: 6,600-21,000) extra deaths (+27%;95%CI: 15-47%) between December 27, 2020 and June 30, 2021. We show that the negative effect of the Delta variant diffusion in July was entirely offset by vaccination in the month of July and August 2021. Finally, we estimate that a complete return to the pre-pandemic life could be safely attained only if >90%, including children from 5 years on, will be vaccinated using mRNA vaccines developed in 2020. In any case, increasing the vaccination coverage will allow further margins for societal reopening even in absence of a pediatric vaccine. These results may support the definition of vaccination targets for countries that have already achieved a broad population coverage.

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