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COVID-19 is a life-threatening multisistemic infection caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Infection control relies on timely identification and isolation of infected people who can alberg the virus for up to 14 days, providing important opportunities for undetected transmission. This note describes the application of rRT-PCR test for simpler, faster and less invasive monitoring of SARS-CoV-2 infection using pooling strategy of samples. Seventeen positive patients were provided with sterile dry swabs and asked to self-collected 2 nasal specimens (#NS1 and #NS2). The #NS1 was individually placed in a single tube and the #NS2 was placed in another tube together with 19 NSs collected from 19 negative patients. Both tubes were then tested with conventional molecular rRT-PCR and the strength of pooling nasal testing was compared with the molecular test performed on the single NS of each positive patient. The pooling strategy detected SARS-CoV-2 RNA to a similar extent to the single test, even when Ct value is on average high (Ct 37-38), confirming that test sensibility is not substantially affected even if the pool contains only one low viral load positive sample. Furthermore, the pooling strategy have benefits for SARS-CoV-2 routinary monitoring of groups in regions with a low SARS-CoV-2 prevalence., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Pratelli, Pellegrini, Ceci, Tatò, Lucente, Capozzi, Camero and Buonavoglia.)

This study evaluated the prevalence of anti-legionella antibodies in workers at hospitals with a long-term history of legionella contamination. The hospitals are located in Milan and Turin, northern Italy, and in Naples and Bari, southern Italy. Antibody prevalence and titres of healthcare workers, medical and dental students and blood donors were assessed. In total 28.5% of subjects were antibody positive, most frequently to L. pneumophila serogroups 7-14. Major differences were observed in seroprevalence and type of legionella antibody in persons from different geographic areas. Healthcare workers had a significantly higher frequency of antibodies compared with blood donors in Milan (35.4 vs 15.9%, P<0.001), whereas in Naples both groups exhibited high antibody frequency (48.8 vs 44.0%) and had a higher proportion of antibodies to legionella serogroups 1-6. Dental workers had a higher seroprevalence than office staff in Bari, but not in Turin, where daily disinfecting procedures had been adopted to avoid contamination of dental unit water. No association was found between the presence of antibodies and the presence of risk factors for legionellosis, nor with the occurrence of pneumonia and/or flu-like symptoms. In conclusion, the presence of legionella antibodies may be associated with occupational exposure in the hospital environment, but there was no evidence of any association with disease.

Various authors have reported the presence of Legionella spp. in dental unit waterlines with prevalence rates reaching, in some cases, 69.7% In order to evaluate the association between occupational exposure to Legionella and risk of infection, anti-Legionella spp. antibodies were measured in 88 dental assistants, 44 of which exposed and 44 not exposed to dental environments. Antibody levels > 1:128 were considered positive for infection. Relative risk was found to be 3.5 (p<0.01). These results confirm the hypothesis that workers in dental health-care settings are at occupational risk for Legionella infection. It is essential, therefore, that surveillance of microbiological quality of dental waterlines be implemented and appropriate disinfection procedures performed where necessary.

Among the microorganism involved in environmental contamination, Legionella spp is actually considered an important infectious hazard. The aim of this study is to evaluate the incidence of Legionella spp in water samples collected from 138 dental unit selected from public outpatient clinics of 6 Italian cities. The samples were taken from oral rinsing cup, air-water syringe, ultrasonic scaler and the turbine to investigate Legionella spp, Pseudomonas aeruginosa and the total heterotrophic count at 36 degrees and 22 degrees. Legionella spp was present in 33,3% dental unit water; but a significant difference was shown among the enrolled cities. In 43,5% of water sample Legionella concentration was 1.000-10.000 CFU/L and in 30,4% was >10.000 CFU/L. L. pneumophila 1 was found in 23,9% of water samples. The results demonstrate that the concentration of Legionella spp in dental unit water lines could be high and this suggests that the exposure to these micoorganism during the dental practise could be a potential health risk both for dental personnel and for the patients too, especially when immunocompromised.

In Italy, although the number of cases of legionellosis notified to the health authorities has significantly increased in recent years, the incidence is still believed to be underestimated. To verify the true frequency and identify the sources of infection, an active clinical-environmental surveillance program was instituted in three hospital facilities in Southern Italy. Between January 2001 and March 2005, a total of 1000 patients admitted to the three hospitals with a diagnosis of pneumonia were enrolled. The urinary antigen and anti-Legionella antibody titre were assayed in each subject, and direct searches for the microorganism were made in biological specimens. Legionellosis was found to be present in 5.9% of the patients. For each of the cases of legionellosis, microbiological surveys were made of the water supply in the public and/or private facilities involved. Overall, 197 water samples of hospital origin and 218 of community origin were analysed: Legionella spp was isolated in 44.2 and 36.7% of the cases, respectively. Comparison of our data with those of the routine surveillance system for the same area (only 7 cases during the period 1997-2000), showed that the frequency of legionellosis is grossly underestimated in Southern Italy. It is therefore necessary to set up more rigorous controls in both hospital and community facilities, so that timely preventive measures can be taken to avoid any further spread of the disease.

A cross-sectional multicenter survey of Italian hotels was conducted to investigate Legionella spp. contamination of hot water. Chemical parameters (hardness, free chlorine concentration, and trace element concentrations), water systems, and building characteristics were evaluated to study risk factors for colonization. The hot water systems of Italian hotels were strongly colonized by Legionella; 75% of the buildings examined and 60% of the water samples were contaminated, mainly at levels of > or =10(3) CFU liter(-1), and Legionella pneumophila was the most frequently isolated species (87%). L. pneumophila serogroup 1 was isolated from 45.8% of the contaminated sites and from 32.5% of the hotels examined. When a multivariate logistic model was used, only hotel age was associated with contamination, but the risk factors differed depending on the contaminating species and serogroup. Soft water with higher chlorine levels and higher temperatures were associated with L. pneumophila serogroup 1 colonization, whereas the opposite was observed for serogroups 2 to 14. In conclusion, Italian hotels, particularly those located in old buildings, represent a major source of risk for Legionnaires' disease due to the high frequency of Legionella contamination, high germ concentration, and major L. pneumophila serogroup 1 colonization. The possible role of chlorine in favoring the survival of Legionella species is discussed.

In dental healthcare surgeries, both workers and patients are regularly exposed to various infectious agents. It is essential therefore that dental healthcare workers have a good knowledge of disinfection systems and that dentists' surgeries be effectively managed so as to reduce or even eliminate the risk of cross infections. In order to evaluate infectious risk prevention methods and describe the procedures used by dental healthcare workers on a daily basis, a sample of dentists who work in public surgeries were asked to anonymously fill up a questionnaire. The results of this survey show that dental healthcare workers are sufficiently well-informed about the infectious hazards present in the workplace and are aware of the high risk of exposure to infections but seem to be especially concerned about blood-borne infections (hepatitis, AIDS). Only 67.5%, however, are immunised against HBV. Individual safety devices are used correctly while there seems to be a lack of knowledge about the proper use of disinfection and sterilization systems. In addition, some dental healthcare workers still today refuse to treat HIV-positive patients.

The frequent occurrence of Legionnaires' disease outbreaks in many countries, including Italy, highlights the importance of epidemiological investigations on this disease. For this purpose, an active surveillance programme of pneumonia patients was carried out in a large hospital in Apulia (Italy) from March 2001 to December 2003. A total of 612 patients were tested for Legionella pneumophila infection by urinary antigen detection and evaluation of antibodies titre. Culture of respiratory specimens was performed on 117 patients. Thirty-seven patients (6%) tested positive for legionellosis: 10 resulted nosocomial cases and 27 as community-acquired. Only 9 cases di Legionella pneumophila infection were reported from Apulia to the routine surveillance system between 1996 and 2000. The results of our study denote the level of underestimation of this disease in Apulia.

The dramatic improvement in knowledge concerning celiac disease (CD) has disclosed the pattern of the associated clinical manifestations and the often atypical or silent presentation of this disease, which makes clinical diagnosis difficult. Also oral manifestations, mostly recurrent apthous stomatitis (RAS) and dental enamel hypoplasia, are atypical signs of CD. Our opinion about the possibility of performing mass-screening to reveal atypical or silent CD is in agreement whit who is asserting that a sistematical case-finding is, at present, the most suitable epidemiological approach. So, we think that patients affected by RAS, or dental enamel hypoplasia, should be considered, even in the absence of any gastrointestinal symptom, at-risk subjects, and should therefore undergo diagnostic procedure for CD.

We investigated Legionella and Pseudomonas contamination of hot water in a cross-sectional multicentric survey in Italy. Chemical parameters (hardness, free chlorine, and trace elements) were determined. Legionella spp. were detected in 33 (22.6%) and Pseudomonas spp. in 56 (38.4%) of 146 samples. Some factors associated with Legionella contamination were heater type, tank distance and capacity, water plant age, and mineral content. Pseudomonas presence was influenced by water source, hardness, free chlorine, and temperature. Legionella contamination was associated with a centralized heater, distance from the heater point >10 m, and a water plant >10 years old. Furthermore, zinc levels of <100 microg/L and copper levels of >50 microg/L appeared to be protective against Legionella colonization [corrected]. Legionella species and serogroups were differently distributed according to heater type, water temperature, and free chlorine, suggesting that Legionella strains may have a different sensibility and resistance to environmental factors and different ecologic niches.

Despite legionellosis surveillance is active in Italy since many years, the disease notification appears still undervalued. A multicentric survey was carried out among 5 big Italian hospitals. It examined 11,435 discharge forms (1999-2001), reporting pneumonia diagnosis. Legionellosis (II class of notify system for infectious disease) was studied among pneumonia diagnosis by discharge forms. According to the ICD9-CM, there's no specific code for legionellosis (this disease is included among "others gram-negative pneumonia"). So the presumed pneumonia imputable to Legionella spp were the 2.7% of the whole number of analyzed discharge forms. Besides, the data regarding the other pneumonia showed that the etiological agent was specified only in the 11.2% of the case. This situation could be rectified both introducing adequate discharge forms codes and promoting the etiological diagnosis during the hospital stay.

Twenty-five caves of speleological and palaeontological interest were investigated for the presence of Cryptococcus spp. within the Apulia region of Italy. Five hundred and forty-five specimens of soil, mud, animal faeces, water and decayed animal and plant remains were examined. Faecal specimens from bats, pigeons and foxes in three caves yielded Cryptococcus neoformans var. neoformans and C. laurentii, C. neoformans var. neoformans and C. albidus were isolated from two soil specimens. Only three caves were positive for the presence of C. neoformans, but the survey documents the finding of a possible natural reservoir in Apulia. It is the first record of occurrence of this yeast in association with cavernicolous habitats, and indicates the potential role of caves in exposing speleologists to life-threatening fungal infections.

The aim of this research was to evaluate the knowledge of cross-infection hazards in private dental practices, and their control procedures. The survey, carried out by questionnaire in 11 Italian cities, showed that dental personnel do not completely follow the main procedures for infection control. The interviewed subjects usually wear gloves (95.5%), masks (90.1%) and glasses (91.2%), less frequently caps (23.9%) and coats (54.9%). They use steam sterilizers (92.9%) and periodically check the effectiveness (80.6%). Regarding individuals protection, 20.5% is not vaccinated against HBV and only 55.2% of those previously vaccinated has checked their immunity. Moreover, the majority of subjects underestimate the infection hazards especially for air-transmitted diseases.

A multicentric Italian investigation on legionnaires' disease is in course to clarify host factors as well as pathogen associated characteristics involved in the infection/disease. The main goal of the research plan is to account for some critical aspects concerning identification and prevention of legionellosis. To improve knowledge on factors associated with Legionella spp colonisation in hot waters, to detect cases and to characterize risk factors in subjects which develop pneumonia are specific objectives of the research programme. Preliminary results show that hot waters of houses and hotels are frequently contaminated (22.6% and 54.6%, respectively), mainly by L. pneumophila. Microbial concentrations were low in domestic waters (<1.000 ufc/l), but higher in samples from the hotels (geom. mean 1.85 x 10(3) ufc/l). Warming system, age of the plant, type of building were risk factors significantly associated with Legionella spp positivity. The active surveillance on patients affected by pneumonia with search for Legionella urinary antigen allowed the identification of 34 cases, 3 of which of nosocomial origin, corresponding to 4.2% of the screened pneumonia. After informed consent, 26 subjects were recruited for a case-control-study to clarify risk factors for the disease.

Fluconazole susceptibility among 800 clinical Candida isolates (60% C. albicans) and two control strains (C. krusei ATCC 6258 and C. parapsilosis ATCC 22019) was tested with the NCCLS M27-A method (gold standard) and six commercial products (Candifast, disk, Etest, Fungitest, Integral System Yeasts, and Sensititre YeastOne). Results were classified as susceptible, susceptible-dose dependent, or resistant using M27-A breakpoints or, for Fungitest, Integral System Yeasts, and Candifast, as susceptible, intermediate, or resistant, according to the manufacturers' instructions. Concordance with NCCLS M27-A results was analyzed with the chi(2) test. Intra- and interlaboratory reproducibility was also evaluated. NCCLS M27-A (90.1%), Etest (93.1%), Sensititre YeastOne (93.1%), disk (96.7%), Fungitest (92.6%), Integral System Yeasts (40.6%), and Candifast (6.0%) classified the indicated percentages of C. albicans isolates as susceptible. Among non-C. albicans strains, the percentages of susceptible isolates were as follows: NCCLS M27-A, 74.0%; Etest, 83.8%; Sensititre YeastOne, 64.1%; disk, 60.6%; Fungitest, 76.6%; Integral System Yeasts, 28.3%; and Candifast, 27.4%. All methods except Candifast and Integral System Yeasts showed good agreement with NCCLS M27-A results for both C albicans and non-C. albicans isolates. Intralaboratory reproducibility was excellent for NCCLS M27-A, Etest, Sensititre YeastOne, disk, and Fungitest (88 to 91%). Similar results emerged from the interlaboratory reproducibility evaluation. Our findings indicate that some commercial methods can be useful for fluconazole susceptibility testing of clinical Candida isolates. Those characterized by a lack of medium standardization and/or objective interpretative criteria should be avoided. Particular caution is necessary when testing is being done for clinical and epidemiological purposes.