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Simonetta Viviani

Simonetta Viviani
Independent Scientific Advisor on vaccines, epidemiology and public health

Doctor of Medicine

About

72
Publications
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Introduction
Simonetta Viviani currently works as Independent Scientific Advisor on vaccines, epidemiology and public health. Simonetta does research in Clinical Trials, Epidemiology and Infectious Diseases.
Additional affiliations
January 2009 - December 2012
January 2005 - present

Publications

Publications (72)
Article
Full-text available
The SARS-CoV-2 Omicron variant has rapidly replaced the Delta variant of concern. This new variant harbors worrisome mutations on the spike protein, which are able to escape the immunity elicited by vaccination and/or natural infection. To evaluate the impact and susceptibility of different serum samples to the Omicron variant BA.1, samples from CO...
Article
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Background: The recently emerged SARS-CoV-2 Omicron variant exhibits several mutations on the spike protein, enabling it to escape the immunity elicited by natural infection or vaccines. Avidity is the strength of binding between an antibody and its specific epitope. The SARS-CoV-2 spike protein binds to its cellular receptor with high affinity an...
Article
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Italy was the second country affected by the SARS-CoV-2 pandemic; the virus spread mainly in Northern Italy with a subsequent diffusion to the center and southern part of the country. In this study, we aimed to assess the prevalence of antibodies against SARS-CoV-2 in the general population of the Siena province in the Tuscany region (Central Italy...
Article
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Influenza is a vaccine preventable disease and vaccination remains the most effective method of controlling the morbidity and mortality of seasonal influenza, especially with respect to risk groups. To date, three types of influenza vaccines have been licensed: inactivated, live-attenuated, and recombinant haemagglutinin vaccines. Effectiveness stu...
Article
For more than a century, epidemic meningococcal disease mainly caused by serogroup A Neisseria meningitidis has been an important public health problem in sub-Saharan Africa. To address this problem, an affordable meningococcal serogroup A conjugate vaccine, MenAfriVac®, was developed specifically for populations in the African meningitis belt coun...
Article
Full-text available
In March 2020, the first pandemic caused by a coronavirus was declared by the World Health Organization. Italy was one of the first and most severely affected countries, particularly the northern part of the country. The latest evidence suggests that the virus could have been circulating, at least in Italy, before the first autochthonous SARS-COV-2...
Article
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Background A phase 2 randomized-controlled safety and immunogenicity trial evaluating different doses of recombinant acellular pertussis vaccine containing genetically-inactivated pertussis toxin (PTgen) was conducted in women of childbearing age in Thailand to identify formulations to advance to a trial in pregnant women. Methods A total of 250 w...
Article
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Background OVX836 is a recombinant protein vaccine targeting the highly conserved influenza nucleoprotein (NP), which could confer broad-spectrum protection against this disease. Methods This was a randomized, placebo-controlled, double-blind, dose-escalating, single center first-in-human study, conducted in 36 healthy adults aged 18-49 years. Twe...
Article
In Italy, the inclusion of measles vaccine in children immunization schedule and the promotion of national mass vaccination campaigns increased measles vaccination coverage. However, measles outbreaks continue to occur increasingly involving adolescents and adults. The aim of this study was to evaluate the prevalence to measles antibody in a sample...
Article
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The recent spreading of new SARS-CoV-2 variants, carrying several mutations in the spike protein, could impact immune protection elicited by natural infection or conferred by vaccination. In this study, we evaluated the neutralizing activity against the viral variants that emerged in the United Kingdom (B.1.1.7), Brazil (P.1), and South Africa (B.1...
Article
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Although in humans West Nile virus is mainly the cause of mild or sub-clinical infections, in some cases a neuroinvasive disease may occur predominantly in the elderly. In Italy, several cases of West Nile virus infection are reported every year. Tuscany was the first Italian region where the virus was identified; however, to date only two cases of...
Article
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SARS-CoV-2 pandemic is causing high morbidity and mortality burden worldwide with unprecedented strain on health care systems. To investigate the time course of the antibody response in relation to the outcome we performed a study in hospitalized COVID-19 patients. As comparison we also investigated the time course of the antibody response in SARS-...
Article
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Background Recombinant pertussis vaccines inducing long-lasting immune responses could help to control the rise in pertussis. We here report on persisting antibody responses 2 and 3 years after booster vaccination with a new generation recombinant acellular pertussis vaccine. Methods Participants of a phase 2/3 randomised-controlled clinical trial...
Article
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Background: Despite efforts to increase coverage by two doses of measles vaccine in Italy, measles continues to circulate, with over 13 000 cases of disease since 2013. This study aimed to evaluate immunity to measles in Italian children and adolescents. Methods: A total of 378 serum samples from subjects aged 9 months-18 years were collected in...
Article
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Before its recent spread, serological investigations conducted between the 1960s and the 1990s showed the wide presence of Zika virus in Africa. According to the World Health Organization, the entire Africa continent is at risk of Zika outbreak due to the presence of the virus, competent vectors, and the low capacity for surveillance and containmen...
Article
According to the World Health Organization, the entire African continent is at risk of a Zika outbreak. To increase data availability on the epidemiology of Zika virus circulation in Africa, we evaluated the immunity to Zika virus in a selected cohort of subjects from West Africa between 2007 and 2012. Human serum samples were collected in 2007 and...
Article
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Varicella is a highly contagious, infectious disease caused by the varicella-zoster virus. Those at higher risk of severe complications are immunocompromised individuals, adults, non-immune pregnant women, and newborns. According to the gestational time, when varicella-zoster virus infection is acquired during pregnancy, serious complications can p...
Article
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Prevention of congenital rubella is achieved by vaccination of susceptible women of childbearing age. In Italy, the National Plan for Measles and Congenital Rubella Elimination 2010-2015 implemented catch-up vaccination activities targeting susceptible adolescents and young adults, including women of childbearing age. The aim of this study was to a...
Article
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Objectives To evaluate seroprevalence against Bordetella pertussis in Tuscany, a large Italian region, from 1992 to 2005 and from 2013 to 2016. Design Seroepidemiological study. Participants 1812 serum samples collected in Tuscany from subjects older than 12 years from 1992 to 2005 and from 2013 to 2016. Outcome measures Specific antibody levels...
Article
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Measles in pregnancy may lead to serious sequelae for newborns and mothers. In Italy assessment of immunity against measles is not recommended as pregnancy screening. This study aimed to assess the immunity against measles in pregnant women from Apulia Region in Southern Italy between 2016 and 2017. Overall, 96.9% of pregnant women were positive fo...
Article
Background: Protection induced by acellular pertussis (aP) vaccines is partial and short-lived, especially in teenagers, calling for novel immunization strategies. Methods: We conducted an investigator-driven proof-of-concept randomized controlled trial in aP-primed adolescents in Geneva to assess the immunogenicity and reactogenicity of a novel...
Article
Background: The immunogenicity of acellular pertussis vaccines and persistence of immunity after vaccination might be improved by using genetically inactivated pertussis toxin (PTgen) instead of chemically inactivated pertussis toxin (PTchem) because of the preservation of conformational epitopes. We assessed the safety and immunogenicity of two v...
Article
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From 2001 to 2017 the Meningitis Vaccine Project (MVP), a Gates Foundation funded partnership between PATH and the World Health Organization (WHO), successfully developed, tested, licensed, and introduced an affordable new Group A meningococcal conjugate vaccine, MenAfriVac(®), in sub-Saharan Africa. The vaccine was well received, and from 2010 to...
Article
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The introduction of a new Group A meningococcal conjugate vaccine, MenAfriVacR, has been a important public health success. Group A meningococcal meningitis has disappeared in all countries where the new Men A conjugate vaccine has been used at public health scale. However, continued control of Group A disease in sub-Saharan Africa will require tha...
Article
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Background: Increasing evidence shows that protection induced by acellular pertussis vaccines is short-lived, requiring repeated booster vaccination to control pertussis disease. We aimed to assess the safety and immunogenicity of a recombinant acellular pertussis vaccine containing genetically inactivated pertussis toxin and filamentous haemagglu...
Article
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Background: An acellular Pertussis (aP) vaccine containing recombinant genetically detoxified Pertussis Toxin (rPT), Filamentous Hemagglutinin (FHA) and Pertactin (PRN) has been developed by BioNet-Asia (BioNet). We present here the results of the first clinical study of this recombinant aP vaccine formulated alone or in combination with tetanus a...
Article
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Background. The rollout of the group A meningococcal vaccine, PsA-TT, in Africa's meningitis belt countries represented the first introduction of a vaccine specifically designed for this part of the world. During the first year alone, the number of people who received the vaccine through mass vaccination campaigns was several hundredfold higher tha...
Article
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Background. The group A meningococcal vaccine (PsA-TT) clinical development plan included clinical trials in India and in the West African region between 2005 and 2013. During this period, the Meningitis Vaccine Project (MVP) accumulated substantial experience in the ethical conduct of research to the highest standards. Methods. Because of the publ...
Article
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Background. Following mass vaccination campaigns in the African meningitis belt with group A meningococcal conjugate vaccine, MenAfriVac (PsA-TT), disease due to group A meningococci has nearly disappeared. Antibody persistence in healthy African toddlers was investigated. Methods. African children vaccinated at 12–23 months of age with PsA-TT were...
Article
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Background. Mass vaccination campaigns of the population aged 1–29 years with 1 dose of group A meningococcal (MenA) conjugate vaccine (PsA-TT, MenAfriVac) in African meningitis belt countries has resulted in the near-disappearance of MenA. The vaccine was tested in clinical trials in Africa and in India and found to be safe and highly immunogenic...
Article
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Background. The determination of the safety profile of any vaccine is critical to its widespread use in any population. In addition, the application of international guidelines to fit local context could be a challenging but important step toward obtaining quality safety data. Methods. In clinical studies of PsA-TT (MenAfriVac), safety was monitore...
Article
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Dengue fever is globally considered underestimated. This study provides Expansion Factors (Efs) for dengue endemic selected countries and highlights critical issues in the use of EFs. We identified dengue epidemiological cohort studies from 2000 to July 2013 through a literature search using PubMed, Web of Science and Lilacs (Latin American and Car...
Article
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Major epidemics of serogroup A meningococcal meningitis continue to affect the African meningitis belt. The development of an affordable conjugate vaccine against the disease became a priority for World Health Organization (WHO) in the late 1990s. Licensing of meningococcal vaccines has been based on serological correlates of protection alone, but...
Article
Group A Neisseria meningitidis epidemics have been an important and unresolved public health problem in sub-Saharan Africa for over a century. The Meningitis Vaccine Project (MVP) was established in 2001 with the goal of developing, testing, licensing, and introducing an affordable group A meningococcal conjugate vaccine for Africa. A monovalent gr...
Article
Background: Roughly half the world's population live in dengue-endemic countries, but no vaccine is licensed. We investigated the efficacy of a recombinant, live, attenuated tetravalent dengue vaccine. Methods: In this observer-masked, randomised, controlled, monocentre, phase 2b, proof-of-concept trial, healthy Thai schoolchildren aged 4-11 yea...
Article
This study compares the immunogenicity and safety of a single dose of a new meningococcal A conjugate vaccine (PsA-TT, MenAfriVac™, Serum Institute of India Ltd., Pune) against the meningococcal group A component of a licensed quadrivalent meningococcal polysaccharide vaccine (PsACWY, Mencevax ACWY(®), GSK, Belgium) 28 days after vaccination in Ind...
Article
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A phase II clinical study was conducted in African toddlers (aged 12 to 23 months), with subjects receiving either investigational meningococcal group A conjugate (PsA-TT), meningococcal ACWY polysaccharide (PsACWY), or Haemophilus influenzae type b (Hib-TT) vaccine. Ten months following vaccination, the 3 study groups were further randomized to re...
Article
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Group A meningococci are the source of major epidemics of meningitis in Africa. An affordable, highly immunogenic meningococcal A conjugate vaccine is needed. We conducted two studies in Africa to evaluate a new MenA conjugate vaccine (PsA-TT). In study A, 601 children, 12 to 23 months of age, were randomly assigned to receive PsA-TT, a quadrivalen...
Article
There are approximately 360 millions chronic carriers of Hepatitis B virus worldwide. Patterns of HB carriage are variable from one region to the other. Regions with rates of carriage over 8% are commonly considered as "high endemicity" regions. HB carriers have a very significant lifetime risk of developing chronic liver diseases such as cirrhosis...
Article
Full-text available
Epidemic meningitis in Africa remains an important and unresolved public health problem. Bacteriologic and epidemiologic data collected over the past 30 years have consistently established the importance of Group A Neisseria meningitidis as the dominant etiologic agent. The meningococcal Group A capsule is the major virulence factor; it is a polysa...
Article
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A double-blind, randomized, controlled phase I study to assess the safety, immunogenicity, and antibody persistence of a new group A conjugate vaccine (PsA-TT) in volunteers aged 18 to 35 years was previously performed. Subjects received one dose of either the PsA-TT conjugate vaccine, meningococcal A/C polysaccharide vaccine (PsA/C), or tetanus to...
Article
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Primary hepatocellular carcinoma is the commonest cancer in The Gambia. The Gambia Hepatitis Intervention Study (GHIS) was established in 1986 to evaluate the protective effectiveness of infant hepatitis B immunization in the prevention of chronic liver disease, particularly, hepatocellular carcinoma and cirrhosis later in adult life. This program...
Conference Paper
Background: Group A meningococci (MenA) continue to cause devastating epidemics of meningococcal disease in sub-Saharan Africa. The Meningitis Vaccine Project (MVP), a Gates Foundation funded partnership between WHO and PATH to accelerate the development and introduction of affordable meningococcal conjugate vaccines for Africa, has coordinated the...
Article
Epidemic meningococcal meningitis is an important public health problem in sub-Saharan Africa. Current control measures rely on reactive immunizations with polysaccharide (PS) vaccines that do not induce herd immunity and are of limited effectiveness in those under 2 years of age. Conversely, polysaccharide conjugate vaccines are effective in infan...
Article
We performed a double-blind, randomized, controlled phase I study to assess safety, immunogenicity, and antibody persistence of the new meningococcal group A conjugate vaccine (PsA-TT) in healthy volunteers aged 18-35 years. Of the 74 male subjects enrolled, 24 received the PsA-TT vaccine (Group 1), 25 received the Meningococcal Polysaccharide Vacc...
Article
Full-text available
We assessed the safety and immunogenicity of a fully liquid, DTPw-HepB-Hib combination vaccine (Quinvaxem) in comparison with separately administered DTPw-Hib and hepatitis B vaccines. Infants participating in this open-label, randomized, phase II study received a primary vaccination course using a 2-3-4 month schedule. Blood samples were taken imm...
Article
We performed a double-blind clinical study to evaluate the safety and immunogenicity of four formulations of a DTwPHib full liquid vaccine, three of which contained fractional doses of the 10 microg-dose of CRM197-Hib conjugate vaccine. A total of 261 infants were enrolled and randomised to receive at 3, 4 and 5 months of age, in a double-blind fas...
Article
Objectives: We evaluated antibody prevalence to measles, polio 1 and 3, and tetanus toxoid antibodies in 8-9 year-old children in The Gambia within the framework of the Gambia Hepatitis Intervention Study (GHIS), a large vaccine trial aimed at evaluating vaccine efficacy against hepatitis B virus (HBV) infection, chronic carriage and primary liver...
Article
Full-text available
Haemophilus influenzae type b (Hib) infection remains a major public health problem in the developing world. We evaluated the safety and immunogenicity of a new PRP-CRM197 conjugate Hib vaccine (Vaxem Hib, Chiron Vaccines), compared with the HibTITER vaccine (Wyeth-Lederle Vaccines), following the World Health Organisation (WHO)'s accelerated sched...
Article
Full-text available
The present study was carried out to evaluate the safety and immunogenicity of the Haemophilus influenzae type b-CRM197 (Hib-CRM197) conjugate vaccine in relation to the change of adjuvant from aluminum hydroxide to aluminum phosphate (AlPO4). The present study was a clinical phase II, observer-blind, randomized, multicenter, controlled study. Subj...
Article
Combining paediatric vaccines is a rational solution to reduce the number of injections during a single clinical visit, to maintain parents' compliance and to extend vaccine coverage. Different diphtheria, tetanus and whole cell pertussis (DTwP)-containing combination vaccines are licensed and used world-wide. This study assessed the immunogenicity...
Article
The primary aim of this study was to assess the tolerability and immunogenicity of a new Haemophilus influenzae type b (Hib)/AlPO4 (CHIRON, SpA) vaccine, in two-month-old healthy infants. Twenty-three subjects were enrolled and administered the new Hib vaccine containing AlPO4 adjuvant at two, three and four months of age concomitantly with diphthe...
Article
To estimate the efficacy in The Gambia (West Africa) of infant hepatitis B vaccination against infection and carriage with the virus at the age of 9 years. The HBV status of 9-year old children vaccinated in infancy was compared to that of unvaccinated children of the same age. Eight percent of the vaccinated children had been infected by HBV compa...
Article
Full-text available
Communicable disease surveillance systems do not always provide accurate or timely data. Furthermore, in Italy, data entry and management are only performed centrally, making the completion of missing data and an improvement in the quality of data difficult to realize. To improve this system, the Istituto Superiore di Sanita conducted a pilot trial...
Article
Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide and a public health concern in many developing countries. The main risk factor is the chronic carriage state of the hepatitis B virus which is found in about 20% of the adult population in many African and Asian countries. Other important risk factors are HCV infection, afla...