Legionella spp. and legionellosis in southeastern Italy: disease epidemiology and environmental surveillance in community and health care facilities

<p>Abstract</p> <p>Background</p> <p>Following the publication of the Italian Guidelines for the control and prevention of legionellosis an environmental and clinical surveillance has been carried out in Southeastern Italy. The aim of the study is to identify the risk factors for the disease, so allowing better programming of the necessary prevention measures.</p> <p>Methods</p> <p>During the period January 2000 - December 2009 the environmental surveillance was carried out by water sampling of 129 health care facilities (73 public and 56 private hospitals) and 533 buildings within the community (63 private apartments, 305 hotels, 19 offices, 4 churches, 116 gyms, 3 swimming pools and 23 schools). Water sampling and microbiological analysis were carried out following the Italian Guidelines. From January 2005, all facilities were subject to risk analysis through the use of a standardized report; the results were classified as <it>good </it>(G), <it>medium </it>(M) and <it>bad </it>(B). As well, all the clinical surveillance forms for legionellosis, which must be compiled by physicians and sent to the Regional Centre for Epidemiology (OER), were analyzed.</p> <p>Results</p> <p><it>Legionella </it>spp. was found in 102 (79.1%) health care facilities and in 238 (44.7%) community buildings. The percentages for the contamination levels < 1,000, 1,000-10,000, > 10,000 cfu/L were respectively 33.1%, 53.4% and 13.5% for samples from health care facilities and 33.5%, 43.3% and 23.2% for samples from the community. Both in hospital and community environments, <it>Legionella pneumophila </it>serogroup (<it>L. pn </it>sg) 2-14 was the most frequently isolate (respectively 54.8% and 40.8% of positive samples), followed by <it>L. pn </it>sg 1 (respectively 31.3% and 33%). The study showed a significant association between M or B score at the risk analysis and <it>Legionella </it>spp. positive microbiological test results (p < 0.001). From clinical surveillance, during the period January 2001 - August 2009, 97 cases of legionellosis were reported to the OER: 88 of community origin and 9 nosocomial. The most frequent symptoms were: fever (93.8%), cough (70.1%), dyspnea (58.8%), shivering (56.7%). Radiological evidence of pneumonia was reported in 68%. The laboratory diagnostic methods used were: urinary antigen (54.3%), single antibody titer (19.8%), only seroconversion (11.1%), other diagnostic methods (14.8%).</p> <p>Conclusions</p> <p>Our experience suggests that risk analysis and environmental microbiological surveillance should be carried out more frequently to control the environmental spread of <it>Legionella </it>spp. Furthermore, the laboratory diagnosis of legionellosis cannot be excluded only on the basis of a single negative test: some patients were positive to only one of the diagnostic tests.</p

Seroprotection against tetanus in the Italian general population

Background: Tetanus is a non-communicable disease, preventable with vaccination. Despite the implemented vaccination strategy, a certain number of tetanus cases per year continue to occur. The aim of the study was to evaluate the seroprevalence of anti-tetanus antibodies in the Italian population by age, sex and geographical area. Methods: To determine the level of tetanus-specific antibodies, an immunoenzymatic assay was used. Results: A total of 3,821 serum samples were collected in the years 2019–20 from healthy subjects aged 6–90 years residing in 13 Italian regions. Overall, 85 % of the tested subjects resulted positive. The rate of subjects protected against tetanus showed a gradual decrease from the younger age groups to the older ones (6–12 years: 93.6 %, 13–24 years: 91.8 %, 25–39 years: 91.0 %, 40–64 years: 78.2 %, ≥ 65 years: 45.3 %); this is particularly evident in the Southern regions and Islands. Moreover, the prevalence of subjects with low protection (&lt;0.1 IU/ ml) was significantly higher in the ≥ 65 age group (10.3 %). Males and females’ prevalence showed a significant difference only in the oldest age group (M: 60.8 %, F: 30.4 %). In general, a higher prevalence was observed for Northern (90.8 %) and Central regions (87.3 %) than Southern regions and Islands (80.0 %). Conclusion: These data, compared with epidemiological ones which showed a high number of cases in the elderly, confirmed that the population with lower protection has a greater risk of contracting the disease, demonstrating the need for adequate immunization through both primary vaccination and boosters for all ages and both sexes, in order to provide lifelong protection

Searching for network modules

When analyzing complex networks a key target is to uncover their modular structure, which means searching for a family of modules, namely node subsets spanning each a subnetwork more densely connected than the average. This work proposes a novel type of objective function for graph clustering, in the form of a multilinear polynomial whose coefficients are determined by network topology. It may be thought of as a potential function, to be maximized, taking its values on fuzzy clusterings or families of fuzzy subsets of nodes over which every node distributes a unit membership. When suitably parametrized, this potential is shown to attain its maximum when every node concentrates its all unit membership on some module. The output thus is a partition, while the original discrete optimization problem is turned into a continuous version allowing to conceive alternative search strategies. The instance of the problem being a pseudo-Boolean function assigning real-valued cluster scores to node subsets, modularity maximization is employed to exemplify a so-called quadratic form, in that the scores of singletons and pairs also fully determine the scores of larger clusters, while the resulting multilinear polynomial potential function has degree 2. After considering further quadratic instances, different from modularity and obtained by interpreting network topology in alternative manners, a greedy local-search strategy for the continuous framework is analytically compared with an existing greedy agglomerative procedure for the discrete case. Overlapping is finally discussed in terms of multiple runs, i.e. several local searches with different initializations.Comment: 10 page

Legionella pneumophila serogroup 3 pneumonia in a patient with low-grade 4 non-Hodgkin lymphoma: a case report

<p>Abstract</p> <p>Introduction</p> <p>Nosocomial legionellosis has generally been described in immunodepressed patients, but <it>Legionella pneumophila </it>serogroup 3 has rarely been identified as the causative agent.</p> <p>Case presentation</p> <p>We report the case of nosocomial <it>L. pneumophila </it>serogroup 3 pneumonia in a 70-year-old Caucasian man with non-Hodgkin lymphoma. Diagnosis was carried out by culture and real-time polymerase chain reaction of bronchoalveolar lavage fluid. The results of a urinary antigen test were negative. A hospital environmental investigation revealed that the hospital water system was highly colonized by <it>L. pneumophila </it>serogroups 3, 4, and 8. The hospital team involved in the prevention of infections was informed, long-term control measures to reduce the environmental bacterial load were adopted, and clinical monitoring of legionellosis occurrence in high-risk patients was performed. No further cases of <it>Legionella </it>pneumonia have been observed so far.</p> <p>Conclusions</p> <p>In this report, we describe a case of legionellosis caused by <it>L. pneumophila </it>serogroup 3, which is not usually a causative agent of nosocomial infection. Our research confirms the importance of carrying out cultures of respiratory secretions to diagnose legionellosis and highlights the limited value of the urinary antigen test for hospital infections, especially in immunocompromised patients. It also indicates that, to reduce the bacterial load and prevent nosocomial legionellosis, appropriate control measures should be implemented with systematic monitoring of hospital water systems.</p

Integrated information increases with fitness in the evolution of animats

One of the hallmarks of biological organisms is their ability to integrate disparate information sources to optimize their behavior in complex environments. How this capability can be quantified and related to the functional complexity of an organism remains a challenging problem, in particular since organismal functional complexity is not well-defined. We present here several candidate measures that quantify information and integration, and study their dependence on fitness as an artificial agent ("animat") evolves over thousands of generations to solve a navigation task in a simple, simulated environment. We compare the ability of these measures to predict high fitness with more conventional information-theoretic processing measures. As the animat adapts by increasing its "fit" to the world, information integration and processing increase commensurately along the evolutionary line of descent. We suggest that the correlation of fitness with information integration and with processing measures implies that high fitness requires both information processing as well as integration, but that information integration may be a better measure when the task requires memory. A correlation of measures of information integration (but also information processing) and fitness strongly suggests that these measures reflect the functional complexity of the animat, and that such measures can be used to quantify functional complexity even in the absence of fitness data.Comment: 27 pages, 8 figures, one supplementary figure. Three supplementary video files available on request. Version commensurate with published text in PLoS Comput. Bio

Completeness of hepatitis, brucellosis, syphilis, measles and HIV/AIDS surveillance in Izmir, Turkey

<p>Abstract</p> <p>Background</p> <p>According to the surveillance system in Turkey, most diseases are notified only by clinicians, without involving laboratory notification. It is assumed that a considerable inadequacy in notifications exists; however, this has not been quantified by any researcher. Our aim was to evaluate the completeness of communicable disease surveillance in the province of Izmir, Turkey for the year of 2003 by means of estimating the incidences of diseases.</p> <p>Methods</p> <p>Data on positive laboratory results for the notifiable and serologically detectable diseases hepatitis A, B, C, brucellosis, syphilis, measles and HIV detected in 2003 in Izmir (population 3.5 million) were collected from serology laboratories according to WHO surveillance standards and compared to the notifications received by the Provincial Health Directorate. Data were checked for duplicates and matched. Incidences were estimated with the capture-recapture method. Sensitivities of both notifications and laboratory data were calculated according to these estimates.</p> <p>Results</p> <p>Among laboratories performing serologic tests (n = 158) in Izmir, 84.2% accepted to participate, from which 23,515 positive results were collected. Following the elimination of duplicate results as well as of cases residing outside of Izmir, the total number was 11,402. The total number of notifications was 1802. Notification rates of cases found in laboratories were 31.6% for hepatitis A, 12.1% for acute hepatitis B, 31.8% for brucellosis, 25.9% for syphilis and 100% for HIV confirmation.</p> <p>Conclusions</p> <p>It was discovered that for hepatitis A, B, C, brucellosis and syphilis, there is a considerable under-notification by clinicians and that laboratory data has the potential of contributing greatly to their surveillance. The inclusion of laboratories in the surveillance system of these diseases could help to achieve completeness of reporting.</p

A comparison of populations vaccinated in a public service and in a private hospital setting in the same area

<p>Abstract</p> <p>Background</p> <p>Improving immunisation rates in risk groups is one of the main objectives in vaccination strategies. However, achieving high vaccination rates in children with chronic conditions is difficult. Different types of vaccine providers may differently attract high risk children.</p> <p>Aim</p> <p>To describe the characteristics of two populations of children who attended a private and a public immunisation provider in the same area. Secondarily, to determine if prevalence of patients with underlying diseases by type of provider differs and to study if the choice of different providers influences timeliness in immunisation.</p> <p>Methods</p> <p>We performed a cross-sectional study on parents of children 2 – 36 months of age who attended a private hospital immunisation service or a public immunisation office serving the same metropolitan area of Rome, Italy. Data on personal characteristics and immunisation history were collected through a face to face interview with parents of vaccinees, and compared by type of provider. Prevalence of underlying conditions was compared in the two populations. Timeliness in immunisation and its determinants were analysed through a logistic regression model.</p> <p>Results</p> <p>A total of 202 parents of children 2–36 months of age were interviewed; 104 were in the public office, and 98 in the hospital practice. Children immunised in the hospital were more frequently firstborn female children, breast fed for a longer period, with a lower birthweight, and more frequently with a previous hospitalisation. The prevalence of high risk children immunised in the hospital was 9.2 vs 0% in the public service (P = 0.001). Immunisation delay for due vaccines was higher in the hospital practice than in the public service (DTP, polio, HBV, and Hib: 39.8% vs 22.1%; P = 0.005). Anyway multivariate analyses did not reveal differences in timeliness between the public and private hospital settings.</p> <p>Conclusion</p> <p>Children with underlying diseases or a low birthweight were more frequently immunised in the hospital. This finding suggests that offering immunisations in a hospital setting may facilitate vaccination uptake in high risk groups. An integration between public and hospital practices and an effort to improve communication on vaccines to parents, may significantly increase immunisation rates in high risk groups and in the general population, and prevent immunisation delays.</p

SV-IV Peptide1–16 reduces coagulant power in normal Factor V and Factor V Leiden

Native Factor V is an anticoagulant, but when activated by thrombin, Factor X or platelet proteases, it becomes a procoagulant. Due to these double properties, Factor V plays a crucial role in the regulation of coagulation/anticoagulation balance

The epidemiology of mumps in Italy

In Italy, although vaccination has been recommended for a number of years, vaccination coverage for mumps is still sub-optimal. The objective of the present study was to evaluate the seroprevalence of mumps antibodies in the Italian population, stratified by age, gender and geographical area. The proportion of individuals positive for mumps antibodies remained stable in the age classes 0-11 months and 1 year (25.4% and 30.8%, respectively) and showed a continuous increase after the second year of life. The percentage of susceptible individuals was higher than 20% in persons 2-14 years of age and exceeded 10% in persons 15-39 years of age. No statistically significant differences were observed by gender or geographical area. Comparison between these results and the data obtained from a 1996 survey showed a statistically significant increase in seroprevalence in the age class 2-4 years. No changes were observed in the other age-groups. The results of this study confirm that the efforts made in recent years to improve vaccination coverage within the second year of life should be strengthened. \ua9 2008 Elsevier Ltd. All rights reserved