The role of hepatitis B vaccine challenge dose in patients with underlying health conditions

We have evaluated the immunological response to Hepatitis B virus (HBV) booster vaccine dose in 129 adults with underlying diseases in comparison with 694 subjects at occupational risk of infection, who have previously completed the primary series and resulted with anti-HBs <10 mIU/mL. After booster dose, 60.5% of the patients with underlying diseases and 14.8% of the subjects at occupational risk resulted seronegative. By comparing two groups, rate of subjects with anamnestic response was higher in at occupational risk group respect to that at risk for medical conditions (OR: 5.99 [95%IC, 3.81-9.41], p < .001). This difference was associated to gender (males/females: OR: 0.619 [95%IC, 0.421-0.910], p = .015) and age (better response for younger people, p = .011).

Safety and Immunogenicity of Conventional Subunit and MF59-adjuvanted Influenza Vaccines in Human Immunodeficiency Virus-1-seropositive Patients

In this study of influenza vaccination, 37 human immunodeficiency virus (HIV)-1-seropositive patients were randomized to receive either a vaccine with a conventional subunit or one adjuvanted with MF59. Blood samples were collected at the time of vaccination, and then 30 and 180 days later, to evaluate immunogenicity, CD4+ T-lymphocyte count and HIV-1 RNA levels. Seroconversion rates against the three viral strains included in the vaccine ranged between 44% and 72% and 53% and 68% for the adjuvanted vaccine and the subunit vaccine, respectively. Other criteria of the European Medicines Evaluation Agency were also met. Vaccination was not associated with serious adverse events. Local and systemic effects were mild and of short duration. CD4+ T-lymphocyte counts and viraemia levels were not negatively affected by vaccination. These results confirmed the safety and immunogenicity of these currently available vaccines in HIV-1-seropositive patients, thus supporting the recommendation for influenza immunization in this high-risk category.

Determinants of adherence to seasonal influenza vaccination among healthcare workers from an Italian region: results from a cross-sectional study

OBJECTIVES

Notwithstanding decades of efforts to increase the uptake of seasonal influenza (flu) vaccination among European healthcare workers (HCWs), the immunisation rates are still unsatisfactory. In order to understand the reasons for the low adherence to flu vaccination, a study was carried out among HCWs of two healthcare organisations in Liguria, a region in northwest Italy.

METHODS

A cross-sectional study based on anonymous self-administered web questionnaires was carried out between October 2013 and February 2014. Through univariate and multivariate regression analysis, the study investigated the association between demographic and professional characteristics, knowledge, beliefs and attitudes of the study participants and (i) the seasonal flu vaccination uptake in the 2013/2014 season and (ii) the self-reported number of flu vaccination uptakes in the six consecutive seasons from 2008/2009 to 2013/2014.

RESULTS

A total of 830 HCWs completed the survey. Factors statistically associated with flu vaccination uptake in the 2013/2014 season were: being a medical doctor and agreeing with the statements 'flu vaccine is safe', 'HCWs have a higher risk of getting flu' and 'HCWs should receive flu vaccination every year'. A barrier to vaccination was the belief that pharmaceutical companies influence decisions about vaccination strategies.

DISCUSSION

All the above-mentioned factors, except the last one, were (significantly) associated with the number of flu vaccination uptakes self-reported by the respondents between season 2008/2009 and season 2013/2014. Other significantly associated factors appeared to be level of education, being affected by at least one chronic disease, and agreeing with mandatory flu vaccination in healthcare settings.

CONCLUSIONS

This survey allows us to better understand the determinants of adherence to vaccination as a fundamental preventive strategy against flu among Italian HCWs. These findings should be used to improve and customise any future promotion campaigns to overcome identified barriers to immunisation.

Experience with pneumococcal polysaccharide conjugate vaccine (conjugated to CRM197 carrier protein) in children and adults

Streptococcus pneumoniae-related infections are a major cause of morbidity and mortality in people of all ages worldwide. Pneumococcal vaccine development started in 1911 with a whole cell vaccine and more recently multivalent plain polysaccharide and polysaccharide conjugate vaccines have been developed. The recent vaccines rely on capsular polysaccharide antigens to induce serotype-specific immune responses. We summarize here the presentations on pneumococcal polysaccharide conjugate vaccine (conjugated to CRM197 carrier protein) given during the integrated symposium organized and funded by Pfizer International Operations during the 22nd European Congress of Clinical Microbiology and Infectious Diseases (ECCMID) 31 March to 3 April 2012, London, UK. A dramatic reduction in the incidence of invasive pneumococcal diseases (IPD) due to vaccine serotypes (VST-IPD) has been reported since the introduction of a hepta-valent pneumococcal conjugate vaccine (PCV7). An indirect (herd) effect has been demonstrated to be associated with PCV7 infant vaccination programmes, with many studies reporting reductions in VST-IPD in populations that are not eligible for PCV7 vaccination. Since 2010, a 13-valent pneumococcal conjugate vaccine (PCV13) has been introduced into national immunization programmes and results from early surveillance suggest that this vaccine also has an impact on the serotypes unique to PCV13, as well as continuing to protect against the PCV7 serotypes. Data from a passive surveillance system in Europe in 2009, for instance, showed that the highest incidence of IPD remains in those aged >65 years and in children <5 years. PCV13 has now been licensed for vaccination of adults >50 years based on safety and immunogenicity data; an efficacy trial is being conducted. Regardless of previous pneumococcal vaccination status, if the use of 23-valent polysaccharide is considered appropriate, it is recommended to give PCV13 first. Novel immunization strategies remain the only practical means to reduce significantly the remaining global mortality and morbidity due to S. pneumoniae in adults.

Pneumococcal vaccination strategies in adult population: perspectives with the pneumococcal 13 - valent polysaccharide conjugate vaccine

Streptococcus pneumoniae (Sp) is a leading cause of infection in people of all ages worldwide, determining a significant impact because of its relatively high incidence rate, the associated economic costs, and the high case-fatality rates. More attention has to be paid for elderly and people with one or more risk factors, in order to reduce health costs and pneumococcal hospital admissions. Moreover, the increasing incidence of antibiotic-resistant Sp strains is a source of concern for its relevant clinical importance in health-care settings. At present, the 23-valent polysaccharide (PPV23) vaccine has shown some limits in terms of protection in the elderly population and against invasive diseases, among adults affected with chronic diseases, non-bacteriemic pneumonias and with immune suppression, in particular in adults with HIV. In December 2011, FDA licensed the 13-valent pneumococcal conjugate vaccine (PCV13) for prevention of pneumonia and invasive diseases (IPDs) in adults aged ≥50 years. The same decision was concomitantly assumed in Europe by EMA. PCV13 has shown superior results both in terms of immunogenicity and of adequate stimulation of a stable and long-lasting immunological memory. European recommendations for PCV13 vaccination in adults are still heterogeneous between Countries. The availability of PCV13 for adults offer a new and promising tool against Sp IPDs and non-IPDs, especially in elderly and at risk populations.

Bacterial carriage and respiratory tract infections in subjects > or = 60 years during an influenza season: implications for the epidemiology of community acquired pneumonia and influenza vaccine effectiveness

INTRODUCTION

During the 2010/11 influenza season an epidemiological prospective cohort active study was organized, to evaluate etiologic role due to the main bacteria and viruses causing Community Acquired Pneumonia (CAP) and Influenza like-illness (ILl) in elderly and to explore the role of the bacterial nose-pharingeal carriage in subjects with respiratory tract infections.

METHODS

An integrated active surveillance of a cohort of adults aged > or = 60 y based on a double prospective and retrospective mechanisms of capture of ILl and CAP cases was organized. Samples were collected from all ILI and CAP prospectively identified. The samples were be tested by multiplex PCR for detection of the main respiratory bacteria and viruses.

RESULTS AND DISCUSSION

The study population amounted to 2,551 adults. During the 2010/11 influenza season, the ILl cumulative incidence was 4.2%, that was twice higher than that calculated by regional sentinel-based Influenza surveillance system during the 2010/11 season in the elderly (2.2%). Among 45 patients with ILI of which had been collected the swab, 17 (37.8%) were positive for influenza viruses and 2 (4.4%) for RSV, 6 (13.3%) patients carried Streptococcus pn and 6 (13.3%) Haemophilus in. In the same period, 7 CAP cases were observed; 3 cases were prospectively identified and samples were collected, while 4 cases were retrospectively detected. The CAP cumulative incidence was 0,3%. The influenza vaccine effectiveness in prevention of laboratory-confirmed influenza emerged by our study was 61%, in condition of good antigenic matching between vaccine and circulating strains observed during the 2010/11. These data contribute to better defining the epidemiological picture of upper and lower respiratory tract infections, fundamental information in light of the recent introduction of new vaccines for prevention of pneumonia in the elderly, including 13-valent conjugate pneumococcal vaccine.

Pneumococcal vaccination in adults: rationale, state of the art and perspectives

Streptococcus pneumoniae (SP) is a leading cause of morbidity and mortality worldwide. Despite the availability, since the early 1980s, of a 23-valent pneumococcal polysaccharide vaccine (PP V23), its recommendation and increased use in the last decades, and the indirect benefits against invasive pneumococcal diseases following the pediatric immunization strategies with the 7-valent pneumococcal conjugate vaccine (PCV7), pneumoccal diseases, particularly Community Acquired Pneumonia (CAP), still remain a substantial burden among older adults in Western countries. The recent availability on the market of a second generation of pneumococcal conjugate vaccines, with an enlarged spectrum of protection against some serotypes not included in the PCV7 (i.e., the 13-valent pneumococcal conjugate vaccine--PCV13), opens new interesting perspectives for improving the control of this significant health-care issue among the entire population. The most interesting and up-dated epidemiological data regarding the impact of SP in adults and the elderly in Western countries, together with the available evidence concerning the efficacy and effectiveness of the PPV23 in the same population, are reported and discussed below.

Improving the protection against Streptococcus pneumoniae with the new generation 13-valent pneumococcal conjugate vaccine

The wide use of the 7-valent Pneumococcal Conjugate Vaccine (PCV7) determined, during the last decade, a dramatic decline in the incidence of Invasive Pneumococcal Diseases (IPD) in infants and children, and also among the non-vaccinated population through the phenomenon known as "herd protection". Furthermore a significant reduction of some non-IPD, such as Community Acquired Pneumonia (CAP) and Acute Otitis Media (AOM) was reported among the pediatric population. At the same time, the high vaccination coverage rates reached with PCV7 contributed to modify the ecology of Streptococcus pneumoniae (Sp), favoring the emergence of some serotypes not included in PCV7 and involved in IPD (replacement phenomenon), thus partially affecting the positive effects of the pediatric immunization programs. To remedy these shortcomings, a new generation of conjugate vaccines, with an enlarged antigenic spectrum of activity than PCV7, has been available since 2010. In particular, the 13-valent Pneumococcal Conjugate Vaccine (PCV13) has been authorized for active prevention of IPD, CAP and AOM in infants and children aged between 6 months and 5 years. More recently, in September 2011, the European Medicine Agency extended the indication for its use to include active immunization of adults aged > or = 50 years for the prevention of IPD, thus opening new interesting opportunities to improve the control of pneumococcal disease among the entire population. The most interesting results from clinical trials using PCV13 in both children and adults are reported and discussed in details.

Impact of influenza during the post-pandemic season: epidemiological picture from syndromic and virological surveillance

INTRODUCTION

Following the observation that 1 or 2 pandemic peak due to the circulation ofAHINlv had occurred in most countries and in most World Health Organization (WHO) Regions, WHO declared on August 10"h, 2010 that the world was moving into the post-pandemic period, whose surveillance presents considerable interest both from epidemiological and clinical point of view. We described the epidemiological picture emerged from syndromic and virological surveillance during the post-pandemic season in Liguria, Italy.

MATERIALS AND METHODS

An Emergency Department Syndrome surveillance system, based on data collected at "San Martino" and IRCCS "G. Gaslini" Liguria Regional Reference University Hospitals for adults and children is active since July 2007. Monitored syndromes include "Influenza-Like Illness" (ILl) and "Low Respiratory Tract Infections" (LRTI). The Ligurian Regional Reference laboratory for Influenza virological surveillance and diagnosis offers rapid detection of influenza viruses by real-time and block RT-PCR, viral culture and genetic characterization by entire sequence analysis of haemagglutinin- and neuraminidase-coding regions in accordance with the international standards established by the global laboratory network.

RESULTS AND DISCUSSION

The integration of syndromic surveillance system and laboratory surveillance for rapid detection and characterization of the disease responsible agent represented a specific and sensitive tool for influenza surveillance. The post-pandemic season was characterized by early onset and by the heaviest impacts for ILI and LRTI among the recent epidemic seasons. In contrast to the picture observed during the pandemic season, the 2010/11 winter was characterized by the intensive circulation of pandemic AH1N1v coupled with sustained activity due to influenza B and Respiratory Syncytial Virus (RSV). Antigenic and molecular characterization of influenza strains confirmed the good matching between circulating and 2010/11 vaccine viruses.

MF-59 adjuvant influence on the functions of gammadelta T cells in HIV-1+ adults immunized with influenza seasonal vaccine

INTRODUCTION

We previously reported that in HIV-1 infected patients circulating Vdelta1 T lymphocytes (Vdelta1) increase and proliferate in vitro in response to Candida albicans (Ca). Herein, we analysed the effects of MF59 adjuvant on the Vdelta1 T cell responses to hemagglutinin (HA) and Ca in HIV-1 seropositive and seronegative adults after influenzal vaccine, to clarify th molecular mechanisms triggered in vivo by an adjuvanted vaccine against influenza virus.

MATERIALS AND METHODS

58 seropositive (HIV-1+) and 48 seronegative (HIV-1-) subjects received influenzal vaccines containing or not the MF59 adjuvant. The follow-up of in vitro T cell proliferation and cytokine production (IL-17A, IL-22, IL-23, IL-6) to HA and Ca antigens were performed at different time points (at basal time and after 30 and 90 days from vaccination) by cytofluorimetric approaches.

RESULTS

We confirmed that in HIV-1 infected individuals the Vdelta1 T cell subset is expanded in HIV-1 infected individuals and moreover the number of circulating Vdelta1 Tcells significantly enhanced in all HIV-1+ subjects on day 90 after influenza vaccination. Regard the follow-up of proliferative responses, the increments of CD3+ response to HA and Vdelta1 T cells to Ca in HIV-1+ individuals were detectable earlier on day 30 for MF59-vaccinated patients, instead on day 90 post-vaccination in HIV(+)-vaccinated without MF59 adjuvant. Of note, production of lL-17A and IL-22, two cytokines with anti-fungal activity, in response to Ca was enhanced (for IL-17A) or restored (for IL-22) by vaccination in HIV-1+ donors, mainly using the MF59-adjuvanted vaccine. Moreover, after vaccination IL-23 and IL-6 production increased in response to HA in the HIV+ and HIV- groups vaccinated with MF59 adjuvant.

CONCLUSIONS

We suggest that in HIV-1 infected patients the circulating Vdelta1 T lymphocytes reactive to Ca upon challenge with influenza virus vaccine receive an activating/enhancing signal mediated by cytokines triggered by the boost with HA antigen particularly in presence of MF59 adjuvant.

The dangerous synergism between influenza and Streptococcus pneumoniae and innovative perspectives of vaccine prevention

Secondary bacterial pneumonia, particularly sustained by Streptococcus pneumoniae (Sp), represents an important cause of excess mortality during both influenza epidemics and pandemics. The lethal synergism between influenza virus and Sp was first suggested by studies performed on samples collected during autopsy from victims of 1918 influenza pandemic, and recently confirmed by data collected during the 2009 A/H1N1v influenza pandemic. Moreover, researches carried out in animal model contributed to partially clarify the pathogenic mechanisms underlying the synergism between these two etiological agents. Since 2000, a seven-valent pneumococcal conjugate vaccine (PCV7) was introduced in the US, and in the following year in Europe, determining substantial and almost immediate benefits in terms of reduction of invasive pneumococcal disease (IPD) in both vaccinated children and adults through induction of herd protection. Furthermore, several researches have recently demonstrated the capacity of the PCV7 to prevent community-acquired pneumonia (CAP) and, in particular, influenza-associated pneumonia hospitalisations among children. Taking into account the above-mentioned positive results obtained with PCV7, the availability of a new generation of conjugate pneumococcal vaccine with an enlarged antigenic spectrum (i.e. PCV13) offers promising perspectives, to improve the control of influenza through the protection offered against its major complications, particularly CAP, not only in children, but also among adults.

Case definitions for human poisonings postulated to palytoxins exposure

A series of case reports and anecdotal references describe the adverse effects on human health ascribed to the marine toxin palytoxin (PLTX) after different exposure routes. They include poisonings after oral intake of contaminated seafood, but also inhalation and cutaneous/systemic exposures after direct contact with aerosolized seawater during Ostreopsis blooms and/or through maintaining aquaria containing cnidarian zoanthids. The symptoms commonly recorded during PLTX intoxication are general malaise and weakness, associated with myalgia, respiratory effects, impairment of the neuromuscular apparatus and abnormalities in cardiac function. Systemic symptoms are often recorded together with local damages whose intensity varies according to the route and length of exposure. Gastrointestinal malaise or respiratory distress is common for oral and inhalational exposure, respectively. In addition, irritant properties of PLTX probably account for the inflammatory reactions typical of cutaneous and inhalational contact. Unfortunately, the toxin identification and/or quantification are often incomplete or missing and cases of poisoning are indirectly ascribed to PLTXs, according only to symptoms, anamnesis and environmental/epidemiological investigations (i.e. zoanthid handling or ingestion of particular seafood). Based on the available literature, we suggest a "case definition of PLTX poisonings" according to the main exposure routes, and, we propose the main symptoms to be checked, as well as, hemato-clinical analysis to be carried out. We also suggest the performance of specific analyses both on biological specimens of patients, as well as, on the contaminated materials responsible for the poisoning. A standardized protocol for data collection could provide a more rapid and reliable diagnosis of palytoxin-poisoning, but also the collection of necessary data for the risk assessment for this family of toxins.

Hospital-acquired infections and leading pathogens detected in a regional university adult acute-care hospital in Genoa, Liguria, Italy: results from a prevalence study

BACKGROUND

A prevalence study aimed to update the epidemiological scenario of Hospital-Acquired Infections (HAI) was performed at the San Martino University Hospital of Genoa, the Regional Reference Adult-care Center in Liguria, Italy, with more than 1300 beds.

MATERIALS AND METHODS

The investigation was performed in all the wards, except the Psychiatric Units, between 19th March and 6Ih April, 2007, using a one-day monitoring system for each ward. International standardized criteria and definitions for the surveillance of HAI were used for the collection of data, which were recorded in specific software for subsequent consolidation, analysis and quality control.

RESULTS

The hospital infection control staff actively monitored 912 inpatients: a total of 84 HAI among 72 patients were diagnosed, with an overall prevalence of infections and affected cases of 9.2% (95% CI: 7.3-11.1) and 7.9% (95% CI: 6.1-9.7), respectively. Urinary Tract Infections (UTI) (30.9%), Respiratory Tract Infections (RTI) (28.6%) and Blood Stream Infections (BSI) (21.4%) were found to be the most frequent infections. As expected, both specific prevalence and localization of HAI varied considerably between wards, with the highest values recorded in Intensive Care Units (ICU) and in Functional Rehabilitation wards. RTI (26.3%) and BSI (13.2%) were found primarily represented in ICU, while the highest values of UTI (13.3%) were registered in Functional Rehabilitation Units. Enterococcus spp. (16.8%), Candida spp. (14%), Pseudomonas spp. (12.2), Staphylococcus aureus (10.7%), Escherichia coli (10.3%) and Coagulase-negative staphylococci (CNS) (9.3%) were the most frequent pathogens isolated. The overall rate of administration of antibiotics was 55.3% and penicillin (26.7%), cephalosporins (22.8%) and fluoroquinolones (17.9%) were found to be the leading antibacterial administered.

CONCLUSION

Results of the present study have been, and are currently, used for orientating surveillance and control hospital policies, planning activities according to a rational and evidence-based approach.

Role of congenital rubella reference laboratory: 21-months-surveillance in Liguria, Italy

INTRODUCTION

Rubella is generally a mild rush fever disease when acquired in childhood, but when infection occurs during the first months of pregnancy, high risk of trans-placental transmission to the foetus and of congenital anomalies exists. In November 2003, a National Plan for measles and congenital rubella elimination was approved in Italy. The aim was to reduce and maintain Congenital Rubella Syndrome incidence lower than 1 case per 100,000 live births/year by 2007. Since June 2006, Liguria Administrative Region recognized U.O. Hygiene, "San Martino" University Hospital, Genoa, as regional reference laboratory for diagnosis of rubella infection during pregnancy and post-partum.

METHODS

Twenty-one-month virological-surveillance results between April 2007 and December 2008 were reported in terms of demographic data, risk factors, access reasons, clinical picture, vaccination, previous rubella disease, laboratory results of pregnant women and newborns.

RESULTS AND CONCLUSION

Since the beginning of surveillance, 65 pregnant women with suspected virus infection and 18 newborns with suspected congenital rubella were followed up. The results of laboratory surveillance highlighted (i) the importance of an early screening, (ii) the suboptimal specificity of chemiluminescent assays, that often yield false positive IgM results and (iii) the fundamental role of second-level laboratory to confirm the serological diagnosis and to detect the virus by molecular techniques.

Evaluation of microbial contamination of air in two haematology departments equipped with ventilation systems with different filtration devices

BACKGROUND

Nosocomial infections (NI) are above all due to health-care workers practices, but also the contamination of the environment could lead to their rise in health-care facilities. Introduction. In the last years, the incidence of NI has increased due to a substantial rise in the number of immuno-compromised patients. These patients are often gathered in hospital areas declared at "high risk" of infection such as Hematology and Bone Marrow Transplant ward. In this study, we evaluated microbial contamination of the air in two divisions with high risk patients, focusing on the validity of the air system with correlation to the presence or not of the HEPA absolute filters.

METHODS

An environmental surveillance study has been carried out in two Divisions of Haematology, in two different Hospitals. Investigations have been performed by sampling air and by analyzing bacterial and fungal growth on microbiology plates after an incubation period.

RESULTS

Unit A, without HEPA filters in the ventilation systems, showed a gradual increase in the bacterial load 20 and 60 days after cleaning of the ventilation system. Mycetes and Aspergilli were not present in basal conditions, at 20 or 60 days after decontamination. Unit B, equipped with HEPA filters placed at the inlet vents, showed extremely low values of the bacterial load either in basal conditions or upon inspection 60 days after cleaning. No mycetes were present.

DISCUSSION

From the results obtained, it was evident that following the cleaning operation, the quality of the air is excellent in both types of equipment, since no mycetes were present and the bacterial load was < 20 CFU/mc in all the sites tested. However, although in subsequent controls mycetes were absent in both types of equipment, a great difference in the suspended bacterial load was found: Unit B was close to sterility whereas in Unit A a progressive increase was observed.

Prospective evaluation of a prevention protocol for lymphedema following surgery for breast cancer

Lymphedema is a common complication of axillary dissection and thus emphasis should be placed on prevention. Fifty-five women who had breast-conserving surgery or modified radical mastectomy for breast cancer with axillary dissection were randomly assigned to either the preventive protocol (PG) or control group (CG) and assessments were made preoperatively and at 1, 3, 6, 12 and 24 months postoperatively. Arm volume (VOL) was used as measurement of arm lymphedema. Clinically significant lymphedema was confirmed by an increase of at least 200 ml from the preoperative difference between the two arms. The preventive protocol for the PG women included preoperative upper limb lymphscintigraphy (LS), principles for lymphedema risk minimization, and early management of this condition when it was identified. Assessments at 2 years postoperatively were completed for 89% of the 55 women who were randomly assigned to either PG or CG. Of the 49 women with unilateral breast cancer surgery who were measured at 24 months, 10 (21%) were identified with secondary lymphedema using VOL with an incidence of 8% in PG women and 33% in CG women. These prophylactic strategies appear to reduce the development of secondary lymphedema and alter its progression in comparison to the CG women.

Decline in pneumonia and acute otitis media after the introduction of childhood pneumococcal vaccination in Liguria, Italy

The effect of the pneumococcal conjugate vaccine immunization programme on pneumococcal-associated or potentially pneumococcal-associated hospital admissions in the Italian region of Liguria was assessed. Hospital admission rates were compared in subjects belonging to birth cohorts before and after the introduction of widespread immunization for 0 - 2-year old children with a seven-valent conjugate vaccine (PCV7). Significant reductions in hospitalization rates for all-cause and pneumococcal pneumonia and for acute otitis media were observed in subjects born after widespread uptake of the vaccine. The preventive fraction (a measure of vaccine effectiveness) ranged from 15.2% for all cause pneumonia to 70.5% for pneumococcal pneumonia. This study contributes to the growing body of information that supports the beneficial effect of PCV7 vaccination.

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

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 Beyer's 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.

Public health research literature on infectious diseases: coverage and gaps in Europe

BACKGROUND

In this study, bibliometric methods were used to investigate prevention and control of infectious diseases (IDs). The aim was to gain an overall view of published research on IDs in Europe as part of the collaborative study SPHERE (Strengthening Public Health Research in Europe).

METHODS

A framework for research on IDs and public health was developed with definitions, keywords, inclusion and exclusion criteria. A detailed web search strategy based on the framework was designed, piloted and refined. The PubMed electronic database was searched for 'infectious diseases' as a whole, and for several subtopic areas, across July 1995 and June 2005. Numbers of publications by year, country, population and Gross Domestic Product were calculated.

RESULTS

Nearly 21,000 publications on the main topic and sub-topics were found, with a progressive increase particularly since 2000. There was a marked heterogeneity between countries. France, Italy, The Netherlands, Spain, Germany, Switzerland, Sweden, UK and Belgium were the most prolific, and Eastern European countries less so. 'Vaccine-preventable diseases', 'Sexually transmitted diseases', 'Drug-resistant infections', 'Insect-arthropod-related diseases' and 'Childhood diseases' were the main fields of scientific production. Research on 'Epidemiology and Surveillance' appeared, in general, to be better represented than research on 'Prevention and Control'.

DISCUSSION

This is the first time such a broad approach has been used to describe public health research on IDs across Europe. A priority should be cooperation between European states where there is little or no, scientific production. Bibliometrics has limitations, but is of value to indicate a general pattern.

Influenza and respiratory syncytial virus in infants and children: relationship with attendance at a paediatric emergency unit and characteristics of the circulating strains

A study was carried out on 2,696 Italian children, aged 0-14 years. The goals were: (1) to define the age-related impact of acute respiratory infections (ARI), measured as the risk of attendance at the Paediatric Emergency Room, (2) to better define the importance and proportion of influenza and respiratory syncytial virus (RSV) infections and (3) to acquire deeper knowledge of the influenza strains circulating in infants and children. A standardised emergency unit attendance risk (EUAR) was calculated, by age group for ARI. Specific EUARs were also calculated for the two pathogens. Pharyngeal swabs were tested by polymerase chain reaction (PCR) for influenza and RSVs. Isolation in Madine-Darby canine kidney cells (MDCK) and Hep cells, haemagglutination inhibition (HI) testing and HA1 gene sequence analysis were performed for influenza viruses. Most of the patients enrolled were aged 0-5 years, 1,139 (84.6%) and 1,061 (78.5%) in the two seasons, respectively. The most represented age class was that of 1 year olds (331 cases in 2001-2002 and 301 in 2002-2003). The highest EUAR for ARI was in patients aged 0-3 years (16.8 and 12.9 during the two seasons). The same was observed on calculating this risk by specific pathogens: 17.4 and 5.5 for influenza and 13.0 and 12.7 for RSV. Virological analysis was performed on 2,696 samples, 595 of which proved positive (22%). The highest number of isolates (326) came from patients aged 1-3 years. RSVs were more often identified than influenza viruses in infants aged up to 1 year (32 vs. 20 isolates). Of 265 strains isolated in 2001-2002, 103 were RSVs (87 type A, 16 B) and 162 were influenza (90 type A, 72 B). HI showed that influenza B viruses were related to two lineages, B/Victoria/2/87 (32%) and B/Yamagata/16/88 (68%). Of 330 strains isolated in 2002-2003, 102 were RSVs (91 type A, 11 B) and 228 were influenza viruses (220 type A, 8 B). A/H3N2 strains belonged to two clusters, A/Panama/2007/99-like and A/Fujian/411/02-like, a new variant. This paper discusses the possible role of the identified flu strains in determining EUARs among the population by age class.

Molecular epidemiology and case-control approaches for management of an outbreak of hepatitis A in Liguria, Italy

INTRODUCTION AND METHODS

Hepatitis A remains an important public health problem in low endemicity areas, because of the social and economic high burden of cyclical outbreaks. In this study we described an outbreak of HAV infection occurred in the city of Genoa and in its proximity and the viral circulation in the post-epidemic period. In order to identify risk factors associated to the illness and to determine the source of infection and the dynamics of virus evolution, we conducted an epidemiological and molecular investigation by a case-control study and by sequence analysis of high variable regions of the genome.

RESULTS

From May to October 2005, 58 HAV hepatitis cases were notified. The case-control study showed that beach establishment attending is strongly associated with HAV hepatitis (OR = 24.5, p-value < 0.01), at multivariate analysis. The profile of epidemic curve, the clinical onset of primary cases who occurred in few weeks and the geographic distribution of cases clearly indicated a common exposure to a point source: the outbreak can be probably associated with a contaminated food product dispensed in the affected area. The outbreak has been mainly caused by a single variant, confirming the common exposure to a point source; this variant previously circulated within homosexual man (MSM) network in Northern Europe. During the outbreak and in the following months, different variants originating from Southeast Asia, Southern America and Northern Africa, have co-circulated: all these cases were related to international travel and none of these had determined secondary cases.

DISCUSSION

The epidemiological picture of hepatitis A in Liguria is characterized by a wide heterogeneity of circulating HAV strains. This pattern could be associated with the increase of imported cases and transmission within network of persons with similar risk factors. Molecular approach coupled to descriptive and analytical epidemiological studies appeared un-replaceable tools for management and control of HAV outbreaks, because of their capacity to recognize infection origin, transmission patterns and dynamics of virus evolution.

Ostreopsis ovata and human health: epidemiological and clinical features of respiratory syndrome outbreaks from a two-year syndromic surveillance, 2005-06, in north-west Italy

There appears to be a lack of data regarding the effects on human health of Ostreopsis ovata, a marine dinoflagellate species usually living in tropical and subtropical areas but recently found with more and more frequency in the Mediterranean Sea.

Performance testing of two new one-step real time PCR assays for detection of human influenza and avian influenza viruses isolated in humans and respiratory syncytial virus

INTRODUCTION AND METHODS

Two real time one-step RT-PCR assays were developed for simultaneous detection and typing of influenza A and B viruses and detection of Respiratory Syncytial Virus (RSV). As regard influenza, primers were designed to amplify specific sequences of gene M of A/H1N1, A/H3N2, A/H5N1, A/H7N7 and A/H9N2 viruses and of gene NP of type B viruses belonging both Yamagata and Victoria lineage. Specificity, analytical and clinical sensitivity, dynamic range, linearity of the new assays were evaluated.

RESULTS

Dynamic ranges for Influenza A and B, and RSV were at least five logs and linearity was conserved. In order to evaluate the specificity, 80 nasopharyngeal swabs resulting Influenza and RSV negative by multiplex nested PCR and cell culture, were tested and 79 resulted negative. The detection limits for influenza A and B, calculated by 95% probit, was 0.008 and 0.09 PFU, respectively, resulting more sensible than nested PCR. A total of 75 specimens (10 A/H1N1, 3 A/H1N2, 8 A/H3N2 Johannesburg/94-like, 10 A/H3N2 Panama/2007/99-like, 10 A/H3N2 Fuijian/411/02-like, 2 A/H5N1, 2 A/H7N7 and 2 A/H9N2, 15 B/Yamagata-like and 13 B/Victoria-like) collected between 1994 and 2004 or received by WHO Influenza Centre, London, were chosen as representative of the circulating strains and tested. All samples resulted positive although one B/Victoria sample was not clear typed. Thirty swabs nested RT-PCR positive for RSV collected during the four seasons, were also analysed by realtime PCR, resulting positive. To evaluate the performance of the new assay on fresh material, 250 specimens, collected during the 2004/05 seasons, were tested by nested-PCR, cell culture and real-time PCR.

DISCUSSION AND CONCLUSION

The new assays provide accurate and sensitive diagnosis of influenza and RSV infection and they represent a sensitive tool for virological surveillance and management of patient with ILI.

Effectiveness of a 23-valent polysaccharide vaccine in preventing pneumonia and non-invasive pneumococcal infection in elderly people: a large-scale retrospective cohort study

This retrospective cohort study evaluated the effectiveness of a 23-valent pneumococcal polysaccharide vaccine in reducing hospital admission for pneumonia, otitis media and exacerbation of asthma or other syndromes due to Streptococcus pneumoniae in 9170 high-risk individuals. Cohort members were followed from 1 January 1998 to 31 December 2002. With regard to preventing hospitalization due to pneumonia, we observed a decrease in the incidence of 1/10000 person-months and a reduction in the relative risk of 38% in the vaccinated cohort compared with the non-vaccinated subjects. A decrease in the risk of hospital admission for asthma, acute otitis media, chronic obstructive pulmonary disease and other respiratory infections was also observed in vaccinated compared with non-vaccinated subjects. The specificity of these findings was confirmed by the lack of a protective effect from vaccination for those outcomes, such as hospitalization 'for all causes' and 'other otorhinolaryngological diagnoses', that were not directly related to pneumococcal disease.

Immunogenicity and tolerability of a trivalent virosomal influenza vaccine in a cohort of HIV-infected children

Twenty-three children infected with the human immunodeficiency virus (HIV) were vaccinated with a trivalent inactivated virosomal influenza vaccine. Serum haemagglutinin inhibition antibody titres were determined for the three viral strains at the time of vaccination and 1 month later. CD4 cell counts and HIV viral loads were measured to evaluate the effect of vaccination on HIV status. Adverse reactions were monitored during the first hour following vaccination by an investigator and then on a continuous basis by the parents. Seroconversion rates against the three viral strains A/H3N2, A/H1N1 and B were 73.9%, 56.5% and 52.2%, respectively. Geometric mean antibody titres increased after 1 month compared with baseline values (A/H3N2: 70.9 versus 13.5; A/H1N1: 24.7 versus 5.8; B: 34.4 versus 9.1). No significant changes were observed in either HIV viral load or CD4 cell count following vaccination. Vaccination was well tolerated with only a few mild, transient symptoms.

Cost-benefit evaluation of influenza vaccination in the elderly in the Italian region of Liguria

Influenza causes considerable morbidity and mortality and the damage to public health can be considerable. The most effective measures available for the prevention of influenza is vaccination. In most industrialised countries the objective of vaccination is to limit the disease among individuals at risk, especially the elderly. During the winter of 2000/2001, General Practitioners (GPs) monitored 14,818 elderly individuals. The objective was to evaluate the weekly incidence of the disease. Furthermore, we carried out a prospective study on 512 elderly individuals, arranged according to vaccination (304 vaccinated and 208 non-vaccinated), with the main objective of assessing the costs of the disease and the efficacy of vaccination. Finally, in order to assess the percentage of vaccinated elderly individuals, we carried out a telephone survey on 500 subjects. Our clinical surveillance study enabled us to establish that morbidity was particularly low in elderly individuals.The results of the prospective study allowed us to estimate the cost-benefit ratio at 8.22, with a net saving of 110.20 Euros for each vaccinated subject. We were also able to establish that the vaccine coverage among elderly individuals was 63%. Our study, though carried out during a low epidemic year, confirms the economic advantage of vaccination in the elderly.

Novel approach to reduce the hepatitis C virus (HCV) window period: clinical evaluation of a new enzyme-linked immunosorbent assay for HCV core antigen

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.

Acute administration of alpha-melanotropin exerts a stimulatory control on puberty

The present experiments were undertaken to throw light on the physiological role played by alpha-MSH in the advent of female puberty. The serum and pituitary alpha-MSH concentrations were determined in prepubertal rats 5, 15, 25, 30, 33 days old and at vaginal opening. The serum levels showed a significant increase on day 30 and the pituitary alpha-MSH levels increased steadily from day 5 to day 33. To determine if a relation exists between the increase in alpha-MSH levels and the peak of LH prior to vaginal opening, prepubertal rats of the same age range as above received an injection of alpha-MSH or saline solution and were sacrificed 30 min later. The peptide increased LH serum levels only at 30 days of age. To examine the hypothesis that alpha-MSH was involved in determining the timing of puberty, prepubertal rats pretreated with estradiol benzoate received an injection of alpha-MSH or saline solution on day 28. This treatment advanced the time of vaginal opening by 2 days in the experimental animals. With the same experimental procedure, an increase in serum levels of LH and progesterone was also observed at 29 days of age. The action of alpha-MSH on GnRH was analysed by incubating median eminence from prepubertal rats 20, 25 and 30 days of age, with the peptide, alpha-MSH increased GnRH release only in 25-day-old rats. The above results show that acute treatment with alpha-MSH induces modifications in the hormones related to puberty and hence allows us to include alpha-MSH in the chain of neuroendocrine events involved in reproductive maturation.