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Influenza is a vaccine-preventable disease. Due to the evolving nature of influenza viruses, the composition of vaccines has to be updated annually. Most of the current influenza vaccines are still produced in embryonated chicken eggs, a well-established process with some limitations.This review focuses on the recombinant DNA technology using baculovirus expression vector system a modern method of manufacturing licensed influenza vaccines. The speed, scalability, biosafety and flexibility of the process, together with the reliability of the hemagglutinin in the vaccine, represent a significant advance toward new platforms for vaccine production.The scenario of vaccine production in the next years seems to be particularly interesting, involving a transition from the current egg-based production to new technologies, such as the cell culture platform, the RNA technology, the plant-based system, and the DNA vaccine. This latter offers great advantages over egg- and cell-based influenza vaccine production. The universal vaccine remains the goal of researchers and ideally would avoid the need for annual reformulation and re-administration of seasonal vaccines. The lesson learned from the COVID-19 pandemic highlights the importance of having different technologies available and able to promptly respond to a great demand of vaccines worldwide.

IntroductionExternal Quality Assessment (EQA) schemes are designed to provide a snapshot of laboratory proficiency, identifying issues and providing feedback to improve laboratory performance and inter-laboratory agreement in testing. Currently there are no international EQA schemes for seasonal influenza serology testing. Here we present a feasibility study for conducting an EQA scheme for influenza serology methods.MethodsWe invited participant laboratories from industry, contract research organizations (CROs), academia and public health institutions who regularly conduct hemagglutination inhibition (HAI) and microneutralization (MN) assays and have an interest in serology standardization. In total 16 laboratories returned data including 19 data sets for HAI assays and 9 data sets for MN assays.ResultsWithin run analysis demonstrated good laboratory performance for HAI, with intrinsically higher levels of intra-assay variation for MN assays. Between run analysis showed laboratory and strain specific issues, particularly with B strains for HAI, whilst MN testing was consistently good across labs and strains. Inter-laboratory variability was higher for MN assays than HAI, however both assays showed a significant reduction in inter-laboratory variation when a human sera pool is used as a standard for normalization.DiscussionThis study has received positive feedback from participants, highlighting the benefit such an EQA scheme would have on improving laboratory performance, reducing inter laboratory variation and raising awareness of both harmonized protocol use and the benefit of biological standards for seasonal influenza serology testing.

The rapid replacement of Omicron BA.1 by BA.2 sublineage is very alarming, raising the question of whether BA.2 can escape the immunity acquired after BA.1 infection. We compared the neutralizing activity toward the Omicron BA.1 and BA.2 sub-lineages in five groups: COVID-19 patients; subjects who had received two doses of mRNA vaccine; subjects naturally infected with SARS-CoV-2 who had received two doses of mRNA; and subjects who had received three doses of homologous or heterologous vaccine. The results obtained highlight the importance of vaccine boosters in eliciting neutralizing antibody responses against Omicron sub-lineages, and suggest that the adenovirus vectored vaccine elicits a lower response against BA.1 than against BA.2 sub-lineage.

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 and is the primary target of neutralizing antibodies. Therefore, protective antibodies should show high avidity. This study aimed at investigating the avidity of receptor-binding domain (RBD) binding antibodies and their neutralizing activity against the Omicron variant in SARS-CoV-2 infected patients and vaccinees. Methods. Samples were collected from 42 SARS-CoV-2 infected patients during the first pandemic wave, 50 subjects who received 2 doses of mRNA vaccine before the Omicron wave, 44 subjects who received 3 doses of mRNA vaccine, and 35 subjects who received heterologous vaccination (2 doses of adenovirus-based vaccine plus mRNA vaccine) during the Omicron wave. Samples were tested for the avidity of RBD-binding IgG and neutralizing antibodies against the wild-type SARS-CoV-2 virus and the Omicron variant. Results. In patients, RBD-binding IgG titers against the wild-type virus increased with time, but remained low. High neutralizing titers against the wild-type virus were not matched by high avidity or neutralizing activity against the Omicron variant. Vaccinees showed higher avidity than patients. Two vaccine doses elicited the production of neutralizing antibodies, but low avidity for the wild-type virus; antibody levels against the Omicron variant were even lower. Conversely, 3 doses of vaccine elicited high avidity and high neutralizing antibodies against both the wild-type virus and the Omicron variant. Conclusions. Repeated vaccination increases antibody avidity against the spike protein of the Omicron variant, suggesting that antibodies with high avidity and high neutralizing potential increase cross-protection against variants that carry several mutations on the RBD.

The micro‐neutralization assay is a fundamental test in virology, immunology, vaccine assessment, and epidemiology studies. Since the SARS‐CoV‐2 outbreak at the end of December 2019 in China, it has become extremely important to have well‐established and validated diagnostic and serological assays for this new emerging virus. Here, we present a micro‐neutralization assay with the use of SARS‐CoV‐2 wild type virus with two different methods of read‐out. We evaluated the performance of this assay using human serum samples taken from an Italian seroepidemiological study being performed at the University of Siena, along with the human monoclonal antibody CR3022 and some iper‐immune animal serum samples against Influenza and Adenovirus strains. The same panel of human samples have been previously tested in enzyme‐linked immunosorbent assay (ELISA) as a pre‐screening. Positive, borderline, and negative ELISA samples were evaluated in neutralization assay using two different methods of read‐out: subjective (by means of an inverted optical microscope) and objective (by means of a spectrophotometer). Our findings suggest that at least 50% of positive ELISA samples are positive in neutralization as well, and that method is able to quantify different antibody concentrations in a specific manner. Taken together, our results confirm that the colorimetric cytopathic effect‐based microneutralization assay could be used as a valid clinical test method for epidemiological and vaccine studies., Highlights High sensitivity of the Micro‐Neutralization assay for anti‐SARS‐CoV‐2 neutralizing antibodies detection in serum samples.CPE‐based (Subjective) and Colorimetric‐based (Objective) Micro‐Neutralization read out are comparable in terms of results provided.50% of S1 ELISA positive serum samples present neutralizing antibodies against wild type SARS‐CoV‐2 virus.

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 COVID-19 patients and vaccinated individuals were tested for their ability to bind and neutralize the original SARS-CoV-2 virus and the Omicron variant BA.1. COVID-19 patients show the most drastic reduction in Omicron-specific antibody response in comparison with the response to the wild-type virus. Antibodies elicited by a triple homologous/heterologous vaccination regimen or following natural SARS-CoV-2 infection combined with a two-dose vaccine course, result in highest neutralization capacity against the Omicron variant BA.1. Overall, these findings confirm that vaccination of COVID-19 survivors and booster dose to vaccinees with mRNA vaccines is the correct strategy to enhance the antibody cross-protection against Omicron variant BA.1.

Genetic and phylogenetic studies indicated that Zika virus (ZIKV) has evolved into 2 major lineages, the African and Asian. However, ZIKV has been described as a single serotype. This study aimed at assessing the cross-neutralization between ZIKV African and Asian lineages strains. Sixthy-five samples collected in 2007 and 30 samples collected from the same subjects in 2011/2012 in West Africa and positive to neutralizing antibody against ZIKV MR-766 strain (African lineage) were tested against ZIKV H/PF/2013 strain (Asian lineage) by microneutralization assay. All samples showing neutralizing antibodies against MR-766 strain showed also neutralizing activity against H/PF/2013 strain, although with lower titers. This is consistent with about 120 amino acid differences between the two strains. Despite differences in the magnitude of neutralizing activity against different ZIKV strains, all samples showed neutralizing antibody titers considered to be protective.

Background. The recent spread of the highly mutated SARS-CoV-2 Omicron variant (B.1.1.529) has raised concerns about protection against COVID-19 in congregate settings such as prisons, characterized by a high risk of transmission and possible difficulties in obtaining adequate vaccination coverage. The present study aims to investigate the spread of an outbreak of COVID-19 in an Italian correctional facility during the dominant circulation of the Omicron BA.1 variant, and also considers BNT162b2 mRNA vaccination coverage among inmates. A COVID-19 screening campaign by RT-PCR was performed on 515 detainees from 4–30 January 2022, in response to an outbreak that began in the correctional facility. Furthermore, 101 serum samples collected from healthy inmates 21 days after having received the second dose of the BNT162b2 vaccine were tested for neutralizing antibodies against both the wild-type SARS-CoV-2 strain and the Omicron BA.1 variant. The global attack rate during the study period was 43.6% (RR 0.8), progressively reducing from unvaccinated inmates (62.7%, RR 1.8) to those who had one dose (52.3%, RR 1.5), two doses (full cycle) (45.0%, RR 1.3), and the third dose (booster) vaccinated group (31.4%, RR 0.7). The percentage of SARS-CoV-2 positive subjects among unvaccinated inmates was significantly higher than in the other groups (p < 0.001), while no significant difference was observed between inmates with one or two vaccine doses. Only two of the positive inmates were hospitalized for COVID-19. The geometric mean titer of neutralizing antibodies in the tested sub-group after two doses of vaccine was lower than in previous studies against the wild-type virus, and showed a complete lack of neutralization against the Omicron variant in 92.1% of individuals. The findings support the need to prioritize vaccination in correctional facilities, as a public health measure to increase the protection of inmates and consequently of prison workers and the community against COVID-19, in coordination with the other prevention strategies.

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 infection have been reported in humans. This study aimed at evaluating the prevalence of antibodies against West Nile virus in the area of Siena Province to estimate the recent circulation of the virus. Human serum samples collected in Siena between 2016 and 2019 were tested for the presence of antibodies against West Nile virus by ELISA. ELISA positive samples were further evaluated using immunofluorescence, micro neutralization, and plaque reduction neutralization assays. In total, 1.9% (95% CI 1.2–3.1) and 1.4% (95% CI 0.8–2.4) of samples collected in 2016–2017 were positive by ELISA and immunofluorescence assay, respectively. Neutralizing antibodies were found in 0.7% (95% CI 0.3–1.5) of samples. Additionally, 0.9% (95% CI 0.4–1.7) and 0.65% (95% CI 0.3–1.45) of samples collected in 2018–2019 were positive by ELISA and immunofluorescence assay, respectively. The prevalence of neutralizing antibodies was 0.5% (95% CI 0.2–1.3). Although no human cases of West Nile infection were reported in the area between 2016 and 2019 and virus prevalence in the area of Siena Province was as low as less than 1%, the active asymptomatic circulation confirms the potential concern of this emergent virus for human health.

In Italy, the influenza season lasts from October until April of the following year. Influenza A and B viruses are the two viral types that cocirculate during seasonal epidemics and are the main causes of respiratory infections. We analyzed influenza A and B viruses in samples from hospitalized patients at Le Scotte University Hospital in Siena (Central Italy). From 2015 to 2020, 182 patients with Severe Acute Respiratory Infections were enrolled. Oropharyngeal swabs were collected from patients and tested by means of reverse transcriptase-polymerase chain reaction to identify influenza A(H3N2), A(H1N1)pdm09 and B. Epidemiological and virological surveillance remain an essential tool for monitoring circulating viruses and possible mismatches with seasonal vaccine strains, and provide information that can be used to improve the composition of influenza vaccines.

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 of Italian population between 1993 and 2018. Human serum samples from subjects aged 3–40 years were collected between 1993 and 2018 and tested for measles IgG antibodies by commercial ELISA. During the study period, the 3–10-year-old age group showed the most important change, with a significant increase in 2003–2007 in both seroprevalence and IgG levels, followed by a slow decrease. The 11–18-year-old age group showed relatively stable seroprevalence rates and IgG levels over the years. The 19–30-year-old group showed stable seroprevalence rates, albeit with a decrease in IgG levels. After a significant increase in 1999–2002, the 31–40-year-old age group had high seroprevalence rates and IgG levels. Despite efforts at national level for implementing measles vaccination, a large proportion of the population is still susceptible to measles. Even if vaccination coverage increases enough to achieve the level of immunization required for herd immunity in new birth cohorts, outbreaks will continue to occur if there are immunity gaps in older age groups. Establishing policies for measles vaccination targeting adult population is needed to close immunity gaps and reach the elimination goal.

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) during 2020. A total of 2480 serum samples collected from January to December 2020 were tested for IgM and IgG antibodies against SARS-CoV-2 by a commercial ELISA. Positive and borderline samples were further tested for the presence of anti-receptor-binding domain (RBD) IgM and IgG antibodies by an in-house ELISA and by a micro-neutralization assay. Out of the 2480 samples tested by the commercial ELISA, 81 (3.3%) were found to be positive or borderline for IgG and 58 (2.3%) for IgM in a total of 133 samples (5.4%) found to be positive or borderline for at least one antibody class. When the commercial ELISA and in-house ELISA/micro-neutralization assay results were combined, 26 samples (1.0%) were positive for RBD IgG, 11 (0.4%) for RBD IgM, and 23 (0.9%) for a neutralizing antibody. An increase in seroprevalence was observed during the year 2020, especially from the end of summer, consistent with the routine epidemiological surveillance of COVID-19 cases.

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 studies allow an assessment of the positive effects of influenza vaccines in the field. The effectiveness of current influenza is suboptimal, being estimated as 40% to 60% when the vaccines strains are antigenically well-matched with the circulating viruses. This review focuses on influenza viruses and vaccines and the role of vaccine effectiveness studies for evaluating the benefits of influenza vaccines. Overall, influenza vaccines are effective against morbidity and mortality in all age and risk groups, especially in young children and older adults. However, the effectiveness is dependent on several factors such as the age of vaccinees, the match between the strain included in the vaccine composition and the circulating virus, egg-adaptations occurring during the production process, and the subject’s history of previous vaccination.

A newly identified coronavirus, named SARS-CoV-2, emerged in December 2019 in Hubei Province, China, and quickly spread throughout the world; so far, it has caused more than 18 million cases of disease and 700,000 deaths. The diagnosis of SARS-CoV-2 infection is currently based on the detection of viral RNA in nasopharyngeal swabs by means of molecular-based assays, such as real-time RT-PCR. Furthermore, serological assays aimed at detecting different classes of antibodies constitute the best surveillance strategy for gathering information on the humoral immune response to infection and the spread of the virus through the population, in order to evaluate the immunogenicity of novel future vaccines and medicines for the treatment and prevention of COVID-19 disease. The aim of this study was to determine SARS-CoV-2-specific antibodies in human serum samples by means of different commercial and in-house ELISA kits, in order to evaluate and compare their results first with one another and then with those yielded by functional assays using wild-type virus. It is important to know the level of SARS-CoV-2-specific IgM, IgG and IgA antibodies in order to predict population immunity and possible cross-reactivity with other coronaviruses and to identify potentially infectious subjects. In addition, in a small sub-group of samples, we performed a subtyping Immunoglobulin G ELISA. Our data showed an excellent statistical correlation between the neutralization titer and the IgG, IgM and IgA ELISA response against the receptor-binding domain of the spike protein, confirming that antibodies against this portion of the virus spike protein are highly neutralizing and that the ELISA Receptor-Binding Domain-based assay can be used as a valid surrogate for the neutralization assay in laboratories which do not have Biosecurity level-3 facilities.

Influenza D virus (IDV) is a novel influenza virus first isolated from swine in 2011 in Oklahoma. Several studies have isolated IDV in cattle from multiple geographic areas, suggesting that cattle could be a possible primary natural reservoir for the virus. To date, few studies have been performed on human samples and there is no conclusive evidence that IDV has the ability to infect humans. This serological study aimed to assess the prevalence of antibodies against IDV in the human population. The IDV used in the serological analysis was influenza D/bovine/Oklahoma/660/2013. The human serum samples, collected in Italy between 2005 and 2017, were randomly selected from the laboratory serum bank and tested by the haemagglutination inhibition (HI) assay. HI positivity has been confirmed using the virus neutralization (VN) assay. Based on HI positivity (HI titers ≥ 10), a low prevalence (5%–10%) was observed between 2005 and 2007. There has been a sharp increase since 2008, resulting in two main peaks in 2009–2010 and 2013–2014, a finding confirmed by the statistical trend analysis. The same pattern and trends can be seen with higher HI titers of >20 and ≥40. The prevalence of antibodies against IDV has increased in the human population in Italy from 2005 to 2017. Low prevalence values between 2005 and 2007 suggest that IDV most probably circulated before its detection in 2011, and perhaps even before 2005. In Italy, IDV has been shown to circulate among swine and bovine herds. It is, therefore, possible that prevalence peaks in humans follow the infection epidemics in animals and do not to persist in the population, resembling a spillover event from the animal reservoir and showing that the virus may not circulate consistently in the human population. However, IDV seemed to have the ability to elicit an immune response in humans.

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 potentially occur for both the woman and the fetus. The present study was conducted to assess the profile of varicella susceptibility in pregnant women in Apulia, a large region in Southern Italy, from 2016 to 2019. The data showed that pregnant women between the age of 15–24 and 40–49 years, the youngest and the oldest, respectively, are the most protected against varicella-zoster virus infection, exceeding the prevalence rate of 90%. Conversely, pregnant women between the age of 25 and 34 years seem to be the most vulnerable and the most at risk for acquiring varicella-zoster virus infection during pregnancy. Analysis of the immunity status against varicella should be introduced as a screening test before pregnancy, together with a strategic vaccination campaign targeting non-immune women of childbearing age, in order to reduce the risk of congenital and perinatal varicella.

Background: Before its recent spread, serological studies conducted between the 1960s and the 1990s showed the wide presence of Zika virus in Africa, but in recent years, limited data are available on its circulation in the African population. The aim of this study was to evaluate the immunity to Zika virus in a selected cohort of healthy subjects from West Africa between 2007 and 2012. Methods: Human serum samples were collected in 2007 and in 2011/2012 from a cohort of 2-29-year-old subjects from Mali, Senegal, and The Gambia. A sample that tested positive by Zika virus IgG ELISA and by Zika virus microneutralization test was defined as positive. Findings: In 2007, the highest seroprevalence to Zika was 21·9% (95%CI 14·08-31·47), found in Senegal among 18-29-year-old subjects. In 2011/2012, the highest seroprevalence, 22·7% (95%CI 13·79-33·79), was found still in Senegal, but in 11-17-year-old subjects. During the two study periods the lowest prevalence was found in Mali, where few positive cases were found and only in 18-29-year-old subjects. The Gambia showed an intermediate seroprevalence. In the three countries, seroprevalence to Zika virus was strongly associated with increasing age. Interpretation: This study contributes to understanding Zika virus circulation within three different ecological and demographic contexts with scarce or no data currently available. Results showed that Zika virus circulated actively in West Africa between 2007 and 2011/2012, but with some geographic specificity. As seropositivity to Zika virus increases with age, women are at high risk to be infected during their reproductive age. Funding Statement: None. Declaration of Interests: The authors declare no conflict of interests. Ethics Approval Statement: The present study was approved by Ethic Committees in Mali, Senegal and The Gambia.

SARS-CoV-2 pandemic is causing high morbidity and mortality burden worldwide with unprecedented strain on health care systems.To elucidate the mechanism of infection, protection, or rapid evolution until fatal outcome of the disease we performed a study in hospitalized COVID-19 patients to investigate the time course of the antibody response in relation to the outcome. In comparison we investigated the time course of the antibody response in SARS-CoV-2 asymptomatic subjects.Study results show that patients produce a strong antibody response to SARS-CoV-2 with high correlation between different viral antigens (spike protein and nucleoprotein) and among antibody classes (IgA, IgG, and IgM and neutralizing antibodies). The peak is reached by 3 weeks from hospital admission followed by a sharp decrease. No difference was observed in any parameter of the antibody classes, including neutralizing antibodies, between subjects who recovered or with fatal outcome. Only few asymptomatic subjects developed antibodies at detectable levels.

[Image: see text] In the absence of effective drugs or vaccines for the treatment of the five Dengue Virus serotypes, the search for novel antiviral drugs is of primary importance for the scientific community. In this context, drug repurposing represents the most used strategy; however, the study of host targets is now attracting attention since it allows identification of broad-spectrum drugs endowed with high genetic barrier. In the last ten years our research group identified several small molecules DDX3X inhibitors and proved their efficacy against different viruses including novel emerging ones. Herein, starting from a screening of our compounds, we designed and synthesized novel derivatives with potent activity and high selectivity. Finally, we synthesized a fluorescent inhibitor that allowed us to study DDX3X cellular localization during DENV infection in vitro. Immunofluorescence analysis showed that our inhibitor colocalized with DDX3X, promoting the reduction of infected cells and recovering the number of viable cells.

A newly identified coronavirus, named SARS-CoV-2, emerged in December 2019 in Hubei Province, China, and quickly spread throughout the world; so far, it has caused more than 49.7 million cases of disease and 1,2 million deaths. The diagnosis of SARS-CoV-2 infection is currently based on the detection of viral RNA in nasopharyngeal swabs by means of molecular-based assays, such as real-time RT-PCR. Furthermore, serological assays detecting different classes of antibodies constitute an excellent surveillance strategy for gathering information on the humoral immune response to infection and the spread of the virus through the population. In addition, it can contribute to evaluate the immunogenicity of novel future vaccines and medicines for the treatment and prevention of COVID-19 disease. The aim of this study was to determine SARS-CoV-2-specific antibodies in human serum samples by means of different commercial and in-house ELISA kits, in order to evaluate and compare their results first with one another and then with those yielded by functional assays using wild-type virus. It is important to identify the level of SARS-CoV-2-specific IgM, IgG and IgA antibodies in order to predict human population immunity, possible cross-reactivity with other coronaviruses and to identify potentially infectious subjects. In addition, in a small sub-group of samples, a subtyping IgG ELISA has been performed. Our findings showed a notable statistical correlation between the neutralization titers and the IgG, IgM and IgA ELISA responses against the receptor-binding domain of the spike protein. Thus confirming that antibodies against this portion of the virus spike protein are highly neutralizing and that the ELISA Receptor-Binding Domain-based assay can be used as a valid surrogate for the neutralization assay in laboratories that do not have biosecurity level-3 facilities.

Toxoplasmosis is a worldwide health problem. Infection in pregnant women can result in severe fetal morbidity or in subclinical neonatal infection; most subclinical cases develop ocular and neurological sequelae. The purpose of this serological study was to assess the prevalence of Toxoplasma gondii in two populations of women of childbearing age in Siena (Tuscany, Central Italy) and Bari (Apulia, Southern Italy) between 2013 and 2017 and in a group of pregnant women in Bari in 2016-2017. Serum samples were tested for the presence of specific anti-Toxoplasma gondii IgG antibodies by a commercially available ELISA test. The percentage of seropositive subjects in Bari was significantly higher than in Siena (22.4% vs. 12.4%) and an age-related trend was observed. A low prevalence of T. gondii infection (13.8%) was observed among the pregnant women tested. In addition to showing a significant difference between Central and Southern Italy, this study provides updated data on T. gondii seroprevalence in women during childbearing age and pregnancy. The results confirm a trend toward a decrease, especially in younger people and pregnant women.Toxoplasma gondii chez les femmes en âge de procréer et pendant la grossesse : étude de la séroprévalence dans le centre et le sud de l’Italie de 2013 à 2017.La toxoplasmose est un problème de santé mondial. L’infection d’une femme enceinte peut entraîner une morbidité fœtale grave ou une infection néonatale subclinique, et la plupart des cas subcliniques développeront des séquelles oculaires et neurologiques. Le but de cette étude sérologique était d’évaluer la prévalence de Toxoplasma gondii dans deux populations de femmes en âge de procréer à Sienne (Toscane, Italie centrale) et Bari (Pouilles, Italie du Sud) entre 2013 et 2017 et dans un groupe de femmes enceintes à Bari en 2016-2017. Des échantillons de sérum ont été testés pour la présence d’anticorps IgG anti-Toxoplasma gondii spécifiques par un test ELISA commercial. Le pourcentage de sujets séropositifs à Bari était significativement plus élevé qu’à Sienne (22,4 % vs 12,4 %) et une tendance liée à l’âge a été observée. Une faible prévalence de l’infection à T. gondii (13,8 %) a été observée chez les femmes enceintes testées. En plus de montrer une différence significative entre le centre et le sud de l’Italie, cette étude fournit des données actualisées sur la séroprévalence de T. gondii chez les femmes en âge de procréer et pendant la grossesse. Les résultats confirment une tendance à la baisse, notamment chez les jeunes et les femmes enceintes.

Summary Herpes simplex viruses (HSV) are among the most widespread causative agents of human viral infections. HSV-2 is one of the commonest causes of genital disease, while HSV-1 is associated primarily with orolabial ulceration; however, recent changes in HSV epidemiology showed an increase in genital and neonatal herpes particularly caused by HSV-1. The main purpose of this study was to assess the seroprevalence of HSV-1 and HSV-2 in a random population in Siena (central Italy) in 2000, 2005 and 2013-2014 and in Bari (southern Italy) in 2005. Moreover, a preliminary study was conducted to investigate the spread of HSV infection in a population of pregnant women and infants in Bari in 2003, 2004 and 2005. Human serum samples were tested for the presence of specific anti-HSV-1 and anti-HSV-2 IgG antibodies using a commercially available ELISA test. For the primary purpose, seroprevalence rates observed in Siena were compared over the years sampled and with the seroprevalence rate found in Bari. Results of seroprevalence in Siena show a decreased trend for both viruses, especially in adolescents and young adults; moreover, HSV-2 seroprevalence rates found in the two cities suggest geographical differences. For the secondary purpose, prevalence rates among pregnant women were compared with the seroprevalence found in women of the general population. No significant difference in prevalence rates were found among pregnant women, while results indicate both viruses are a source of infection in infants.

Sandfly fever viruses are transmitted by the bite of phlebotomine sandflies; serotypes sandfly fever Naples virus, sandfly fever Sicilian virus and sandfly fever Cyprus virus cause febrile illness, whereas Toscana virus (TOSV) may cause neuroinvasive infections. Although TOSV is an important cause of aseptic meningitis in central and southern Italy, in many cases the infection is asymptomatic, leading to underestimation of the actual spread of the virus. This serosurvey aimed to assess the seroprevalence of TOSV in a random population in Siena (Tuscany, central Italy) in 2003–2004 and 2013–2014 and Bari (Apulia, southern Italy) in 2004 and 2015. 2132 serum samples were tested for the presence of anti-TOSV/SFNV IgG by means of ELISA and IFA commercial tests. Seroprevalence rates were compared in the two cities and over a ten-year period in the same city. Seroprevalence results in the Siena population (22.95% in 2003–2004 vs 26.75% in 2013–2014) confirmed the endemic circulation of TOSV and closely related viruses in central Italy, without major changes over the last decade, while no significant prevalence was observed in Bari (2.90% in 2004 vs 1.85% in 2015). Keywords: Toscana virus, Sandfly, Seroprevalence, Phlebovirus, Italy

Background: Colorectal cancer is a leading cause of tumor death, a consequence primarily of the spreading of malignant cells to liver and lung. Despite a range of interventions for liver metastases, the present knowledge of few specific molecular targets may contribute to late diagnosis and poorly effective therapy. Objective: To review the most innovative methodology employed to profile the signature(s) of metastatic colorectal cancer (mCRC) and to address diagnostic/therapeutic agents. Methods: A broad range Medline search was conducted, with particular attention to the search terms ‘liver metastasis signature’, in combination with ‘targeting’ and ‘nanotechnology’. Results/conclusions: Studies aimed at the discovery of molecular signatures of cancers and metastasis are ongoing; the future of cancer/metastasis targeting is nanoparticle-mediated drug delivery.

The influenza viruses have the ability to agglutinate erythrocytes by binding to sialic acid receptors on the host cell. Human influenza viruses preferentially bind to sialic acid linked to galactose by α 2,6 linkage, while avian influenza viruses preferentially bind to sialic acid linked to Gal by 2,3 linkage. There is a close correlation between the ability of influenza A viruses to agglutinate erythrocytes from different animal species and their receptor specificity. The haemagglutination and haemagglutination inhibition assays are influenced by the species of erythrocytes. To provide an overview of the expression of sialic acid receptors on different erythrocytes, avian (turkey, chicken, pigeon) and mammalian (sheep, horse, human) species have been analysed. The erythrocytes from the same avian and mammalian species have been evaluated by haemagglutination and haemagglutination inhibition assays with seasonal and avian strains. Chicken, turkey and human erythrocytes display both types of linkages. Horse and sheep erythrocytes show almost exclusively a sialic acid α 2,3 Gal linkage, while pigeon erythrocytes express almost exclusively a sialic acid α 2,6 Gal linkage. Chicken and turkey erythrocytes seem to be the most appropriate for both assays with seasonal influenza strains, in addition to pigeon erythrocytes, particularly for the B strains. In the case of the avian strain, chicken erythrocytes are suitable for haemagglutination assay and horse erythrocytes for haemagglutination inhibition assay. The choice of erythrocytes has a significant impact on the titres measured by both assays., Journal of Preventive Medicine and Hygiene, Vol 59, No 1 (2018): 2018591