Stefano Tardivo

Respiratory symptoms, asthma, atopy and Chlamydia pneumoniae IgG antibodies in a general population sample of young adults

AbstractBackground: This study was designed to test the association of Chlamydia pneumoniae infection with respiratory symptoms and atopy. Methods: A general population sample of 369 young adults (aged 20-44 years) completed a questionnaire on respiratory symptoms and underwent skin prick testing. C pneumoniae IgG and IgM serum titers were measured by micro-immunofluorescence. Prior infection was defined by titers of IgG ≥ 1:32, acute infection by titers of IgG ≥ :512 and/or IgM ≥ 1:16. Results: The prevalence of cough and phlegm was higher in subjects with (19.0%) than in those without (11.4%) prior C. pneumoniae infection (p = 0.01). A similar difference was found for wheezing (14.3% vs 8.0%; p = 0.05), whereas the percentage of asthmatics was equally distributed between seropositive and seronegative subjects. IgG titers ≥ 1:128 were found more frequently in atopic subjects (p = 0.04). After adjusting for any confounding factors, cough and phlegm (but not wheezing) were found significantly associated with C. pneumoniae positivity, both for 1 : 32 (OR 1.80; 95% CI: 1.01-3.36; p = 0.05) and for 1 : 128 titers (OR 2.31; 95% CI: 1.20-4.42; p = 0.01). A significant association was also found for atopy, for titers ≥ 1 : 128 (OR 1.73; 95% CI: 1.01-3.20, p = 0.05). Acute infection was not associated with respiratory symptoms or asthma. Conclusion: We conclude that C. pneumoniae infection is associated with cough and phlegm and may have a role in the pathogenesis of chronic respiratory diseases. Moreover, our results indicate a relationship between atopy and C. pneumoniae infection.

Seroprevalence of Chlamydia pneumoniae antibodies in a young adult population sample living in Verona

SummaryThe aim of the study was to evaluate the prevalence of antibodies to Chlamydia pneumoniae in a random population sample of 369 young adults (age 20–44 years), living in Verona, Italy. IgG and IgM titers were measured by micro-immunofluorescence. IgG antibodies, greater or equal to 16, were found in 104/177 (58.8%) men and 76/192 (39.6%) women (p < 0.001). No relationship was found between IgG seropositivity, age, social class, education and family size. Factors positively associated with IgG seropositivity including smoking ( p < 0.001), occupational status (employed vs unemployed: p = 0.02; students vs unemployed: p < 0.01) and living area (suburban [65.0%] vs urban area [45.3%]: p = 0.03). The geometric mean of IgG titers was higher in students (GM: 26.05) than in both employed (GM: 11.02) and unemployed persons (GM: 4.80) (p < 0.01 and p < 0.001, respectively). IgG titres ≥ 512 and/or IgM titers ≥ 16 (suggestive of a recent C. pneumoniae infection) were found in 39 subjects (10.6%). Recent infection was more frequent in spring (14.9%), with no significant variation in the other seasons (mean prevalence 6.7%) (p < 0.01). Recent infection was also associated with cigarette smoking. On the other hand, no significant association was found between respiratory symptoms and serologic evidence of recent infection. In conclusion: 1) the prevalence of antibodies to C. pneumoniae in young adults from Verona is similar to that found in European countries, and therefore, in Europe, it seems not related to latitude or climate; 2) male sex, tobacco smoking, employment status and living in a suburban area are independent risk factors of infection; 3) the infection is subclinical in most cases.

Prevention of healthcare associated infections: medical and nursing students' knowledge in Italy.

BACKGROUND The training of health workers is a key issue for the prevention of healthcare associated infections. OBJECTIVES To evaluate knowledge of nursing and medical students concerning the prevention of healthcare associated infections. DESIGN A cross-sectional study. SETTING University hospitals in nine Italian cities. PARTICIPANTS One thousand four hundred sixty one healthcare students (607 medical students and 854 nursing students). METHODS The study was performed using a questionnaire investigating 3 areas, each having different possible points: standard precautions=12; hand hygiene=8; healthcare associated infections=5, for an overall perfect score of 25. Scores that met a cutoff ≥17.5 were considered to be indicative of an acceptable level of knowledge. Factors associated with an acceptable level of knowledge were analyzed using a logistic regression model. RESULTS Mean overall score (±SD) was 18.1 ± 3.2. Nursing students (18.6 ± 2.9) obtained a higher overall score than medical students (17.4 ± 3.5) (p<0.001). Weighed scores (±SD) by area were: 10.3 (±2.0) for standard precautions, 5.0 (±1.3) for hand hygiene and 2.8 (±1.1) for healthcare associated infections. Knowledge level concerning the three areas was different between medical and nursing students (p<0.001). The probability of finding acceptable knowledge was smaller for medical students (OR: 0.54 p<0.0001) and for students aged ≥24 years (OR: 0.39 p<0.0001). CONCLUSION The overall score showed an acceptable level of knowledge for the whole sample; but, considering separately the two curricula, only nursing students reached the minimum acceptable score. It seems important to investigate what is working better in nursing than in medical education in order to implement and validate new teaching approaches.

Attendance at chlorinated indoor pools and risk of asthma in adult recreational swimmers

To study a potential correlation between attendance at chlorinated indoor pools and the onset of asthma in adult leisure swimmers. 1136 adult swimmers attending indoor pools in the city of Verona completed a modified ECRHS questionnaire. The cumulative time spent in the pools was calculated on the basis of the mean frequency and duration of weekly swim activity for every year of attendance. The median value (320 h) was used to divide participants into 2 groups. Other questions concerned the family history of allergies, the medical diagnosis and the onset of asthma. The prevalence of respiratory symptoms in the study group was compared with that of a general population sample. New-onset asthma, first identified at least 12 months after the start of regular pool attendance, was more prevalent among swimmers characterized by a higher cumulative pool attendance (23/514, 4.5%) than in swimmers who were attending indoor pools less frequently (2/508, 0.4%; ratio 11.1, 95% CI 2.6-47.4). The statistical analysis revealed an independent association between the cumulative lifetime hours spent in indoor swimming pools and new onset asthma (relative risk 1.05, 95% CI 1.02-1.07). Respiratory symptoms were less frequent in the study population versus a general population sample (prevalence ratio 0.26-0.68). Attendance at chlorinated indoor pools may constitute a risk factor for developing asthma in leisure adult swimmers. Future research and efforts should aim at improving disinfection techniques, hygiene and ventilation in indoor swimming pools in order to provide an unobjectionable ambient for salubrious swim activities.

Trends, risk factors and outcomes of healthcare- associated infections within the Italian network SPIN-UTI

BACKGROUND Implementing infection control measures in light of healthcare-associated infection (HAI) surveillance data can prevent HAIs. Surveillance has been associated with a reduction of HAI in intensive care unit (ICU) patients, though the reasons for this improvement remain unclear. AIM To evaluate changes in healthcare-associated infection (HAI) rates during three surveys of the Italian Nosocomial Infections Surveillance in Intensive Care Units (ICUs) network (SPIN-UTI) six-year project and to explore sources of variation of indicators of HAI in the 65 participating ICUs. METHODS The SPIN-UTI network adopted the European protocols for patient-based HAI surveillance. Cumulative incidence, incidence density, infection rates adjusted for device-days, and device utilization ratios were calculated for each survey and compared. To identify risk factors multiple logistic regression analyses were performed. Crude excess mortality was computed as the difference between the crude overall case-fatality rate of patients with and without HAI. FINDINGS The risk of ICU-acquired infections increased in the third survey compared with previous (relative risk: 1.215; 95% confidence interval: 1.059-1.394). Among risk factors, the number of hospitalized patients requiring ICU admission and the Simplified Acute Physiology Score II increased from 73.7% to 78.1% and from 37.9% to 40.8% respectively. Although mortality rates remained unchanged, HAIs trebled the risk of death. Acinetobacter baumannii was the most frequently reported micro-organism in the third survey (16.9%), whereas in the previous surveys it ranked third (7.6%) and second (14.3%). CONCLUSIONS The study highlighted the increased risk of HAI, at least partially explained by the greater severity and number of hospitalized patients requiring ICU admission. Furthermore, the management of intubation procedures and of ventilated patients was identified as a potential target for infection control interventions to decrease the growing risk of HAI in ICUs.

Operating theatre ventilation systems and microbial air contamination in total joint replacement surgery: Results of the GISIO-ISChIA study

BACKGROUND Recent studies have shown a higher rate of surgical site infections in hip prosthesis implantation using unidirectional airflow ventilation compared with turbulent ventilation. However, these studies did not measure the air microbial quality of operating theatres (OTs), and assumed it to be compliant with the recommended standards for this ventilation technique. AIM To evaluate airborne microbial contamination in OTs during hip and knee replacement surgery, and compare the findings with values recommended for joint replacement surgery. METHODS Air samplings were performed in 28 OTs supplied with unidirectional, turbulent and mixed airflow ventilation. Samples were collected using passive sampling to determine the index of microbial air contamination (IMA). Active sampling was also performed in some of the OTs. The average number of people in the OT and the number of door openings during the sampling period were recorded. FINDINGS In total, 1228 elective prosthesis procedures (60.1% hip and 39.9% knee) were included in this study. Of passive samplings performed during surgical activity in unidirectional airflow ventilation OTs (U-OTs) and mixed airflow OTs (M-OTs), 58.9% and 87.6% had IMA values >2, respectively. Of samplings performed during surgical activity in turbulent airflow OTs (T-OTs) and in turbulent airflow OTs with the surgical team wearing Steri-Shield Turbo Helmets (TH-OTs), 8.6% and 60% had IMA values ≤ 2, respectively. Positive correlation was found between IMA values and the number of people in the OT and the number of door openings (P < 0.001). In addition, correlation was found between active and passive sampling (P < 0.001). CONCLUSION These findings challenge the belief that unidirectional systems always provide acceptable airborne bacterial counts.

Serological and molecular identification of Legionella spp. isolated from water and surrounding air samples in Italian healthcare facilities

BACKGROUND Legionella is an intracellular microorganism living in natural and artificial aquatic environments. Although its transmission to humans is linked to the inhalation of contaminated aerosols, there is no validated air sampling method for the control and prevention of the disease. The aim of the present study was to provide more information on the distribution of Legionella spp. in indoor environments and to determine whether the same Legionella strains are isolated from air and water samples. METHODS Ten healthcare facilities located in seven regions of Italy were enrolled. The serological typing of Legionella spp. from water samples and the surrounding air by active and passive sampling was assessed using polyvalent and monovalent antisera. Subsequently, the strains identified as Legionella pneumophila (Lpn) underwent molecular typing by sequence-based typing (SBT) using seven genes (flaA, pilE, asd, mip, mompS, proA, and neuA). The allelic profile number was assigned using the European Working Group for Legionella Infections-SBT database. RESULTS Lpn serogroup 6 was the most prevalent serogroup; it was found simultaneously in the air and water samples of three different healthcare facilities. In the remaining seven hospitals, Lpn serogroups 1, 6, 7, 9, and 12 were isolated exclusively from water samples. The molecular investigation showed that Lpn strains in the water and air samples of each positive healthcare facility had the same allelic profile. Strains, identified as sequence types (STs) 728 and ST 1638+ST 1324, were isolated in two respective healthcare facilities, and a new strain, identified as ST 1989, was obtained in one healthcare facility. CONCLUSION The application of the SBT method allowed to verify the homology among Legionella strains from water samples and the surrounding air. The results showed that the same Lpn strains were present in the air and water samples, and a new Legionella strain was identified.

Evaluation of Legionella Air Contamination in Healthcare Facilities by Different Sampling Methods: An Italian Multicenter Study

Healthcare facilities (HF) represent an at-risk environment for legionellosis transmission occurring after inhalation of contaminated aerosols. In general, the control of water is preferred to that of air because, to date, there are no standardized sampling protocols. Legionella air contamination was investigated in the bathrooms of 11 HF by active sampling (Surface Air System and Coriolis®μ) and passive sampling using settling plates. During the 8-hour sampling, hot tap water was sampled three times. All air samples were evaluated using culture-based methods, whereas liquid samples collected using the Coriolis®μ were also analyzed by real-time PCR. Legionella presence in the air and water was then compared by sequence-based typing (SBT) methods. Air contamination was found in four HF (36.4%) by at least one of the culturable methods. The culturable investigation by Coriolis®μ did not yield Legionella in any enrolled HF. However, molecular investigation using Coriolis®μ resulted in eight HF testing positive for Legionella in the air. Comparison of Legionella air and water contamination indicated that Legionella water concentration could be predictive of its presence in the air. Furthermore, a molecular study of 12 L. pneumophila strains confirmed a match between the Legionella strains from air and water samples by SBT for three out of four HF that tested positive for Legionella by at least one of the culturable methods. Overall, our study shows that Legionella air detection cannot replace water sampling because the absence of microorganisms from the air does not necessarily represent their absence from water; nevertheless, air sampling may provide useful information for risk assessment. The liquid impingement technique appears to have the greatest capacity for collecting airborne Legionella if combined with molecular investigations.

Knowledge about tuberculosis among undergraduate health care students in 15 Italian universities: a cross-sectional study

BackgroundThe Italian Study Group on Hospital Hygiene of the Italian Society of Hygiene, Preventive Medicine and Public Health conducted a multicentre survey aiming to evaluate undergraduate health care students’ knowledge of tuberculosis and tuberculosis control measures in Italy.MethodsIn October 2012–June 2013, a sample of medical and nursing students from 15 Italian universities were enrolled on a voluntary basis and asked to complete an anonymous questionnaire investigating both general knowledge of tuberculosis (aetiology, clinical presentation, outcome, screening methods) and personal experiences and practices related to tuberculosis prevention. Data were analysed through multivariable regression using Stata software.ResultsThe sample consisted of 2,220 students in nursing (72.6%) and medicine (27.4%) courses. Our findings clearly showed that medical students had a better knowledge of tuberculosis than did nursing students.Although the vast majority of the sample (up to 95%) answered questions about tuberculosis aetiology correctly, only 60% of the students gave the correct responses regarding clinical aspects and vaccine details. Overall, 66.9% of the students had been screened for tuberculosis, but less than 20% of those with a negative result on the tuberculin skin test were vaccinated. Multivariable regression analysis showed that age and type of study programme (nursing vs. medical course) were determinants of answering the questions correctly.ConclusionsAlthough our data showed sufficient knowledge on tuberculosis, this survey underlines the considerable need for improvement in knowledge about the disease, especially among nursing students. In light of the scientific recommendations concerning tuberculosis knowledge among students, progress of current health care curricula aimed to develop students’ skills in this field is needed.

Assessing safety culture in NICU: psychometric properties of the Italian version of Safety Attitude Questionnaire and result implications

RATIONALE, AIMS AND OBJECTIVE Neonatal intensive care units (NICUs) are a high-risk setting. The Safety Attitude Questionnaire (SAQ) is a widely used tool to measure safety culture. The aims of the study are to verify the psychometric properties of the Italian version of SAQ, to evaluate safety culture in the NICUs and to identify improvement interventions. METHOD A cross-sectional study was conducted in 6 level III NICUs. The SAQ was translated into Italian and adapted to the context, a confirmatory factor analysis (CFA) was performed to validate the questionnaire. RESULTS 193 questionnaires were collected. The mean response rate was 59.7% (range 44.5%-95.7%). The answers were analysed according to six factors: f1 - teamwork climate, f2 - safety climate, f3 - job satisfaction, f4 - stress recognition, f5 - perception of management, f6 - working conditions. The CFA indexes were adequate (McDonalds omega indexes varied from 0.74 to 0.94, the SRMR index was equal to 0.79 and the RMSEA index was 0.070, 95% CI = 0.063-0.078). The mean composite score was 57.6 (SD 17.9), ranging between 42.3 and 69.7 on a standardized 100-point scale. We highlighted significant differences among units and professions (P < 0.05). CONCLUSIONS The Italian version of the SAQ proved to be an effective tool to evaluate and compare the safety culture in the NICUs. The obtained scores significantly varied both within and among the NICUs. The organizational and structural characteristics of the involved hospitals probably affect the safety culture perception by the staff.