Giancarlo Icardi

Intradermal influenza vaccine for older adults: a randomized controlled multicenter phase III study.

In a 3-year, randomized, controlled, open-label phase III trial enrolling 3707 adults aged > or = 60 years we evaluated whether the immunogenicity of an intradermal trivalent inactivated seasonal influenza vaccine, containing 15 microg of haemagglutinin per strain per 0.1 ml dose, is superior to that of a conventional intramuscular vaccine. Intradermal vaccine was given using an intradermal microinjection system. After the first vaccination, both vaccines satisfied the immunogenicity criteria for influenza vaccines for older adults set out in European regulatory guidelines, and geometric mean haemagglutination inhibition antibody titers and seroprotection rates were higher (statistically superior) with intradermal vaccination. Higher immune responses with intradermal vaccine were also observed after the 2nd and 3rd annual vaccinations. Both vaccines were well tolerated with similar systemic reactogenicity profiles. This intradermal influenza vaccine for older adults is a beneficial option for influenza protection, consistently enhancing antibody responses without compromising safety.

Cross-protection by MF59-adjuvanted influenza vaccine: neutralizing and haemagglutination-inhibiting antibody activity against A(H3N2) drifted influenza viruses.

Adjuvants enhance antibody response against vaccination. We compared the ability of MF59-adjuvanted and non-adjuvanted subunit influenza vaccines, containing A/Wyoming/3/03(H3N2), to confer cross-protection against four consecutive drifted strains in the elderly. Neutralizing and haemagglutination-inhibiting antibody were measured. MF59-adjuvanted vaccine induced a stronger booster response against A/Panama/2007/99(H3N2) than non-adjuvanted vaccine. A/Panama/2007/99(H3N2) circulated widely during the previous 5 years and was included in vaccines over four consecutive seasons. Broader serological protection against drifted strains that circulated 1 and 2 years after vaccination with A/Wyoming/3/03(H3N2) was observed with MF59-adjuvanted vaccine. Thus, MF59-adjuvanted vaccine confers greater immunogenicity than non-adjuvanted vaccines in vulnerable populations.

Novel Approach To Reduce the Hepatitis C Virus (HCV) Window Period: Clinical Evaluation of a New Enzyme-Linked Immunosorbent Assay for HCV Core Antigen

ABSTRACT The window period in hepatitis C virus (HCV) infection is still a major problem in ensuring blood safety. HCV RNA detection by nucleic acid amplification technology-based tests has contributed to reduce the infectivity of blood products, but it is expensive, time-consuming and affected by a high prevalence of false-positive results. The aim of this study was to assess the performance of a newly developed enzyme immunoassay for the detection of HCV core antigen and its suitability for use in the screening of blood units in order to identify infecting samples that do not contain specific antibodies. For evaluation of laboratory performance, different samples were selected: to evaluate specificity, we tested 2,586 sera from blood donors, 500 general population samples, and 58 “difficult sera”. All samples were tested by two screening assays, and results were negative. To estimate clinical sensitivity, 103 HCV RNA-positive, anti-HCV-negative samples, 6 natural seroconversion panels, and 9 commercial seroconversion panels were tested. Intra- and interassay precision were determined on two HCV-RNA-positive, anti-HCV-negative sera. Seventeen (0.66%) blood donor samples, 2 (0.4%) general population samples, and 2 (3.44%) difficult sera were initially reactive; 3 sera were positive on repetition. These 21 samples tested by reverse transcription-PCR were negative. The clinical sensitivity calculated with seroconversion panels and seroconverted patient samples was very similar to PCR sensitivity: 95% of PCR-positive, antibody-negative samples contained detectable HCV antigen. Data on intra- and interassay precision showed dispersion indices with values of less than 10%. In conclusion, the HCV antigen assay showed high sensitivity and specificity and could become a useful means of improving the safety of blood and blood products.

Incidence of candidaemia and relationship with fluconazole use in an intensive care unit

OBJECTIVES Candida spp. are the most important non-bacterial pathogens in critically ill patients. The aim of this study was to evaluate trends in the incidence of candidaemia and the distribution of Candida albicans and non-albicans over a 9 year period (1999-2007), and to assess their relationship with fluconazole use. METHODS This was an interventional cross-over study. Patients admitted to the intensive care unit (ICU) who developed a clinically and microbiologically documented candidaemia were analysed. Fluconazole was used as prophylaxis in critically ill patients until 2002; from January 2003 infectious disease consultants strongly discouraged its use. Fluconazole use, measured as defined daily dose per 1000 patient-days, was calculated. The main outcome of the study is the evaluation of the restriction policy in terms of change in fluconazole use and in incidence of candidaemia. RESULTS During the 108 month period (January 1999-December 2007), a total of 213 episodes of candidaemia (average incidence 1.42 episodes/10 000 patient-days/year, range 0.36-3.02 episodes) were recorded in a mixed medical and surgical ICU in Italy. C. albicans was the most prevalent isolated species (n = 98, 46%); non-albicans (n = 115, 54%) were mainly represented by Candida parapsilosis (n = 46, 22%) and by Candida glabrata (n = 28, 13%). Segmented regression analysis of the interrupted time series showed that a change in the fluconazole prophylactic strategy resulted in a significant reduction in fluconazole use from the second semester of 2002. A dramatic decrease in the incidence of fungaemia due to C. non-albicans was observed from the second semester of 2003 (intervention effect in the second semester of 2007: -2.31/10 000 patient-days); minor changes in the incidence of C. albicans fungaemia emerged (intervention effect in the second semester of 2007: -0.23/10 000 patient-days). CONCLUSIONS The study showed a clear correlation between fluconazole use control and decreasing incidence of non-albicans candidaemia. Even if fluconazole remains a first-line treatment option in several cases of invasive candidiasis, its prophylactic use should be carefully evaluated.

Universal childhood immunisation against Streptococcus pneumoniae: The five-year experience of Liguria Region, Italy

Liguria was the first Italian Administrative Region, since 2003, to actively recommend free-of-charge immunisation, of all infants, with heptavalent Pneumococcal Conjugate Vaccine (PCV-7), within a research pilot-project. Vaccination coverage among infants rapidly increased from 42.8% in 2003 to 83.3% in 2004, progressively reaching levels of 93.4% in 2007. Two scientific projects have been carried out, aimed: (i) to assess the immunogenicity of PCV-7 and of a hexavalent vaccine Diphtheria-Tetanus-Trivalent Acellular Pertussis-Hepatitis B-Inactivated Polio Virus-Haemophilus influenzae type B (DTaP-HBV-IPV-Hib) when co-administered to healthy infants at 3, 5 and 11-12 months of age (routine schedule), and (ii) to evaluate the effect of the immunisation campaign in preventing pneumococcal-associated hospitalisations. Results in 151 infants showed the high immunogenicity of the vaccines, seroprotection rates, measured 1 month after the third dose, ranging between 97.3% (serotype 6 B) and 100% (serotypes 4 and 9 V) for PCV-7 and between 99.3% and 100% against common antigens of hexavalent vaccine. Monitoring nearly 70,000 children, aged 0-24 months, during the period 2000-2007, and comparing hospitalisation rates occurred in subjects belonging to birth cohorts before and after the introduction of widespread immunisation, a significant decline for all-cause and pneumococcal pneumonia and for acute otitis media was observed, with preventive fractions of 15.2%, 70.5% and 36.4%, respectively.

Hepatitis C virus in the new era: Perspectives in epidemiology, prevention, diagnostics and predictors of response to therapy

Despite the great successes achieved in the fields of virology and diagnostics, several difficulties affect improvements in hepatitis C virus (HCV) infection control and eradication in the new era. New HCV infections still occur, especially in some of the poorest regions of the world, where HCV is endemic and long-term sequelae have a growing economic and health burden. An HCV vaccine is still no available, despite years of researches and discoveries about the natural history of infection and host-virus interactions: several HCV vaccine candidates have been developed in the last years, targeting different HCV antigens or using alternative delivery systems, but viral variability and adaption ability constitute major challenges for vaccine development. Many new antiviral drugs for HCV therapy are in preclinical or early clinical development, but different limitations affect treatment validity. Treatment predictors are important tools, as they provide some guidance for the management of therapy in patients with chronic HCV infection: in particular, the role of host genomics in HCV infection outcomes in the new era of direct-acting antivirals may evolve for new therapeutic targets, representing a chance for modulated and personalized treatment management, when also very potent therapies will be available. In the present review we discuss the most recent data about HCV epidemiology, the new perspectives for the prevention of HCV infection and the most recent evidence regarding HCV diagnosis, therapy and predictors of response to it.

MF59-adjuvanted vaccine: a safe and useful tool to enhance and broaden protection against seasonal influenza viruses in subjects at risk.

Importance of the field: Vaccination is universally considered as the most effective tool for the prevention of influenza, which represents a significant burden, both from a health-care and a socio-economic viewpoint. Conventional non-adjuvanted vaccines have shown suboptimal immunogenicity in the elderly, in patients with serious chronic diseases or the immunocompromised and in young children. The protection offered by non-adjuvanted vaccines may be further reduced by periodic antigenic drifts. Areas covered in this review: Between the several strategies proposed to address the need for more immunogenic vaccines than the conventional ones, the most successful strategy is represented by the use of adjuvants. Since 1997, an MF59-adjuvanted subunit influenza vaccine has been licensed in several countries and used in the elderly worldwide. Available data on the safety, immunogenicity and effectiveness of this vaccine have been reported and discussed in details. What the reader will gain: The MF59-adjuvanted vaccine has been shown to enhance immunogenicity and to confer cross-reactivity against heterologous influenza viral strains in the elderly, in adults with serious underlying medical conditions and in healthy infants and young children. Furthermore, its effectiveness has been demonstrated in older adults, reducing hospitalizations for pneumonia, cardiovascular and cerebrovascular diseases. Take home message: The vaccine is safe, with an acceptable tolerability profile, thus representing a valid option to optimize the control of seasonal influenza.

Safety and immunogenicity of two influenza virus subunit vaccines, with or without MF59 adjuvant, administered to human immunodeficiency virus type 1-seropositive and -seronegative adults.

ABSTRACT The objective of this study was to evaluate and compare both the safety and tolerability and the humoral and cell-mediated immune responses for two influenza virus subunit vaccines, one with MF59 adjuvant (Fluad) and one without an adjuvant (Agrippal), in healthy and in human immunodeficiency virus type 1 (HIV-1)-infected adult individuals. To achieve this aim, an open, randomized, comparative clinical trial was performed during the 2005-2006 season. A total of 256 subjects were enrolled to receive one dose of vaccine intramuscularly. Blood samples were taken at the time of vaccination and at 1 and 3 months postvaccination. A good humoral antibody response was detected for both vaccines, meeting all the criteria of the Committee for Medical Products for Human Use. After Beyers correction for prevaccination status, Fluad exhibited better immunogenicity than Agrippal, as shown from the analysis of the geometric mean titers, with significant differences for some virus strains; however, no definitive conclusions on the clinical significance of such results can be drawn, because the method used to estimate antibody response is currently nonstandard for influenza virus vaccines. Significant induction of an antigen-specific CD4+ T-lymphocyte proliferative response was detected at all time points after immunization, for both the vaccines, among HIV-1-seronegative subjects. This was different from what was observed for HIV-1-infected individuals. In this group, significance was not reached at 30 days postvaccination (T30) for those immunized with Agrippal. Also when data were compared between treatment groups, a clear difference in the response at T30 was observed in favor of Fluad (P = 0.0002). The safety profiles of both vaccines were excellent. For HIV-1-infected individuals, no significant changes either in viremia or in the CD4+ cell count were observed at any time point. The results showed good safety and immunogenicity for both vaccines under study for both uninfected and HIV-1-infected adults, confirming current recommendations for immunization of this high-risk category.

Leptin has no role in determining severity of steatosis and fibrosis in patients with chronic hepatitis C.

OBJECTIVE:The presence of steatosis is a common histological finding in patients with chronic hepatitis C (CHC). The causes of the severity of this condition are not yet clear, although both metabolic and viral factors supposedly are involved. In this study our aim was to examine the possible influence that leptin levels, hepatitis C virus (HCV) RNA levels, and hepatitis G virus (HGV) infection have on the severity of steatosis and on the presence and degree of fibrosis in patients with CHC.METHODS:One hundred eighty-two CHC patients with histological findings of steatosis were chosen from among a cohort of patients referred to our center for staging of liver disease. Among them 48 CHC patients were accurately selected so as to rule out possible confounding factors for the presence of steatosis (diabetes mellitus, hyperlipemia, obesity, alcohol). Leptin levels, HCV RNA levels, and HCV genotype, and the presence of HGV RNA were assessed in these patients and related to histological findings.RESULTS:We found that leptin levels in CHC patients were similar to those in healthy subjects. No relationship was found between leptin levels and severity of steatosis. HCV RNA levels, HCV genotype, and the presence of HGV infection were no different among CHC patients with various degrees of steatosis. Leptin was not related to different degrees of fibrosis, whereas higher viral load was the only parameter associated to higher fibrosis scores.CONCLUSIONS:These findings suggest that the degree of steatosis in patients with CHC does not seem to depend on serum leptin levels or on viral factors, at least as far as HCV viremia and genotype and HGV infection are concerned. The severity of fibrosis does not seem to be influenced by leptin levels, whereas HCV viral load does seem to play some role.

Impaired Response to Influenza Vaccine Associated with Persistent Memory B Cell Depletion in Non-Hodgkin’s Lymphoma Patients Treated with Rituximab-Containing Regimens

Influenza vaccination is generally recommended for non-Hodgkin’s lymphoma (NHL) patients, but no data are available about the activity of this vaccine after treatment with rituximab-containing regimens. We evaluated the humoral response to the trivalent seasonal influenza vaccine in a group of NHL patients in complete remission for ≥6 mo (median, 29 mo) after treatment with rituximab-containing regimens (n = 31) compared with age-matched healthy subjects (n = 34). B cell populations and incidence of influenza-like illness were also evaluated. For each viral strain, the response was significantly lower in patients compared with controls and was particularly poor in patients treated with fludarabine-based regimens. In the patient group, the response to vaccination did not fulfill the immunogenic criteria based on the European Committee for Medicinal Products for Human Use requirements. Among the patients, CD27+ memory B cells were significantly reduced, and their reduction correlated with serum IgM levels and vaccine response. Episodes of influenza-like illness were recorded only in patients. These results showed that NHL patients treated with rituximab-containing regimens have persisting perturbations of B cell compartments and Ig synthesis and may be at particular risk for infection, even in long-standing complete remission.