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The methods employed to detect non-tuberculous mycobacteria on environmental samples are essentially those classically used in clinical microbiology, which envisage a decontamination step to reduce the overgrowth of non-mycobacterial organisms before plating them on the culture medium. The aim of this study was to propose alternative culture techniques to improve non-tuberculous mycobacteria detection in environmental samples. We used artificially contaminated samples to compare the membrane filter washing procedure against direct plating of membrane filters on culture media in relation to M.chimaera and M.chelonae recovery efficiency. Moreover, we compared the efficacy of NTM Elite agar in inhibiting the growth of aquatic bacteria with that of cetylpyridinium chloride and N -acetyl-L-cysteine sodium hydroxide decontamination treatments. The washing procedure yielded a low release of both mycobacterium strains (6.6% for Mycobacterium chimaera and 7.5% for Mycobacterium chelonae) from the membrane filters; on the contrary, direct plating of membrane filters led to a 100% cell recovery. Water sample pretreatment with N -acetyl-L-cysteine sodium hydroxide (1%), despite achieving complete suppression of non-acid fast bacilli, caused a reduction in mycobacteria growth. Decontamination with cetylpyridinium chloride (0.005%) was found to be ineffective against Methylobacterium spp. and Burkholderia multivorans. NTM Elite agar was ineffective against B. multivorans , but it inhibited the growth of all other aquatic bacteria. Our results indicate that NTM Elite agar provides a valid alternative method of recovering non-tuberculous mycobacteria from environmental samples. It does not involve a decontamination step and provides greater recovery efficiency by skipping the washing step and directly plating the filters on the media. [Display omitted] • Non-tuberculous mycobacteria are highly susceptible to chemicals used to reduce the overgrowth of non-mycobacterial organisms • No data have been published on the sensitivity of the NTM culture applied to water samples. • The ECDC protocol (membrane filter washing) does not ensure a good cell recovery from the membrane, causing negative results. • Direct membrane filter plating on NTM Elite agar is a valid alternative method of recovering NTM from environmental samples. [ABSTRACT FROM AUTHOR]

We evaluated the diagnostic performances of 2 media (BCYE, MWY) on 951 Legionella -positive hospital water samples. MWY allowed detecting Legionella in 89.2% of samples, but in 10.8% (103/951) Legionella was found on BCYE plates only. In samples where Legionella was isolated with other microorganisms (663/951), MWY was essential to detect the majority of positive samples (349/663, 52.6%), as fewer plates resulted unreadable; however, in those containing Legionella only, a higher frequency of positive samples was recorded with BCYE (94.8%, 273/288) compared to MWY (85.1%, 245/288). Considering the 484 concordant positive samples, overall Legionella counts were significantly higher on BCYE (P = 0.0029), with 47% of samples showing higher counts on BCYE compared to MWY plates. Furthermore, discordant samples (positive on only one medium) showed different relative proportions between Legionella pneumophila and non- pneumophila , the latter being found more frequently on BCYE only (P = 0.0296).Our findings confirm the appropriateness of the ISO 11731:2017 update. [Display omitted] [ABSTRACT FROM AUTHOR]

Background: The prevention and control of legionellosis in hospital settings involves environmental sampling, among other measures. The data yielded by sampling constitute an important means of risk assessment and provide a valid basis on which to plan remedial (cleansing and disinfection) and preventive (maintenance) interventions. This retrospective study had 2 objectives: (1) to evaluate the utility of biofilm sampling at distal sites and (2) to identify an efficient environmental sampling strategy. Methods: Samples of hot water and biofilm were collected between June 1999 and March 2008 from 41 hospitals in Italy''s Piemonte region. We analyzed results of the samples (water and biofilm) taken from the same site and results of the water samples taken from the recirculation loop and water samples taken from the distal sites during the same sampling run. Results: Microbiological analysis was performed on 3910 pairs of samples (water/biofilm). In 81% of the pairs, the results were concordant; in 17% of the pairs, Legionella was isolated only from the water samples, and in only 2% of the pairs was Legionella isolated from the biofilm sample alone. Data from 299 sampling runs show that 79% (236) of results from the water samples taken from the recirculation loop and water samples taken from the distal sites during the same sampling run were concordant, and 21% (63) were discordant. Conclusions: Our findings suggest that hospitals could safely adopt a simpler (water sampling only without biofilm sampling) and more efficient (monitoring of the entire system through sampling of recirculation loop water) environmental sampling policy. [Copyright &y& Elsevier]

• SARS-CoV-2 seroprevalence in Italy among samples from autumn 2019 was investigated. • A second serosurvey was conducted in September-October 2021. • Two seropositive individuals were identified in 2019 (before the first official case in Italy). • Independent testing confirmed results. • Estimated seroprevalence was 0.27% and 6.21% in 2019 and 2021, respectively. The objective was to estimate the seroprevalence of SARS-CoV-2 in autumn 2019 (before case zero was identified in Italy) and 2021 among residual sera samples from health care users in the Piedmont region of northwestern Italy. Two serosurveys were conducted. Using a semiquantitative method, samples were tested for the presence of immunoglobulin G (IgG) antibodies against the S1 domain of the spike protein. Samples with positive test results from the 2019 survey were independently retested using a multiplex panel to detect IgG antibodies against the receptor binding domain, S1 and S2 domains, and nucleocapsid. Samples with positive test results from the 2021 survey underwent repeat testing with enzyme-linked immunosorbent assay to detect anti-nucleocapsid IgG antibodies. Prevalence rates according to gender and age groups, together with their respective 95% confidence intervals (CIs), were calculated. Overall, the proportion of samples with positive test results was 2/353 in 2019 and 22/363 in 2021, with an estimated seroprevalence of 0.27% (95% CI 0-1.86) and 6.21% (95% CI 3.9-9.31) in 2019 and 2021 respectively. Results of this study support the hypothesis that the virus was circulating in Italy as early as autumn 2019. The role of these early cases in broader transmission dynamics remains to be determined. [ABSTRACT FROM AUTHOR]

Quantitative polymerase chain reaction (qPCR) offers rapid, sensitive, and specific detection of Legionella in environmental water samples. In this study, qPCR and qPCR combined with propidium monoazide (PMA-qPCR) were both applied to hot-water system samples and compared to traditional culture techniques. In addition, we evaluated the ability of PMA-qPCR to monitor the efficacy of different disinfection strategies. Comparison between the quantification obtained by culture and by qPCR or PMA-qPCR on environmental water samples confirms that the concentration of Legionella estimated by GU/L is generally higher than that estimated in CFU/L. Our results on 57 hot-water-system samples collected from 3 different sites show that: i) qPCR results were on average 178-fold higher than the culture results (Δ log 10 = 2.25), ii) PMA-qPCR results were on average 27-fold higher than the culture results (Δ log 10 = 1.43), iii) propidium monoazide–induced signal reduction in qPCR were nearly 10-fold (Δ log 10 = 0.95), and that iv) different degrees of correlations between the 3 methods might be explained by different matrix properties, but also by different disinfection methods affecting cultivability of Legionella . In our study, we calculated the logarithmic differences between the results obtained by PMA-qPCR and those obtained by culture, and we suggested an algorithm for the interpretation of PMA-qPCR results for the routine monitoring of healthcare water systems using a commercial qPCR system (iQ-check real-time PCR kit; Bio-Rad, Marnes-la-Coquette, France). [ABSTRACT FROM AUTHOR]

Abstract: The study aim was to determine retrospectively whether the parallel use of 2 media [buffered charcoal yeast extract (BCYE) and medium of Wadowsky and Yee (MWY)] to isolate Legionella spp. from water samples taken from hospital water supply systems increased the sensitivity of the culture method as compared with methods/protocols in which only seeding on a selective medium is used. We analyzed the results obtained from 931 positive water samples. In 484 of the 931 positive water samples, Legionella spp. was isolated in the presence of other microorganisms; in 83% (400/484), we used MWY to count suspected colonies, which gave a lower number of unreadable plates. In the 447 samples containing only Legionella spp., the highest frequency of positive samples (93%, 418/447) was obtained with BCYE, whereas seeding on MWY yielded 78% (348/447) (P < 0.001). Evaluation of the influence of the media on the Legionella spp. counts obtained by the 2 media showed that BCYE agar produced significantly higher counts than MWY (P < 0.001). The major conclusions that may be drawn from our data are as follows: 1) BCYE gives a high recovery rate of positive samples (93%) and a much greater yield of Legionella spp. than MWY; 2) BCYE was necessary for the detection of non–L. pneumophila spp. which grew poorly on selective media; 3) selective media [MWY or GVPC (glycine, vancomycin, polymyxin B, and cycloheximide)] were necessary for the recovery of Legionella spp. when the non-selective medium (BCYE) was difficult to interpret because of contaminating background flora. The use of different media is recommended for routine water tests in hospitals. [Copyright &y& Elsevier]

• Vaccination in pregnancy is greatly effective in ensuring high antibody coverage. • There are wide differences in anti-PT IgG between vaccinated and unvaccinated women. • High IgG titres are strongly encouraging with a view to transplacental immunity. • Vaccinated women had protective levels of antibodies at 33–37 pregnancy weeks. • Vaccinating pregnant women against pertussis is still a valuable preventive strategy. Pertussis (whooping cough) is a highly infectious disease caused by Bordetella pertussis. Mothers lacking adequate immunity and contracting the disease represent the biggest risk of transmission to new-borns, for which the disease is often a threat. The aim of the study was to estimate the frequency of pertussis susceptibility among pregnant women, in order to point out the need for a vaccine recall during pregnancy, and to evaluate the antibody response in already vaccinated women. A cross-sectional observational study was conducted in the blood test centre of "St. Anna" Obstetrics and Gynaecology Hospital in Turin (Piedmont, Italy). Eligibility criteria included pregnant women coming to the centre for any blood test, aged 18 or above and with gestational age between 33 and 37 weeks at the moment of the blood draw. The data collection was carried out from May 2019 to January 2020 and the concentration of anti-Pertussis Toxin (anti-PT) IgG was measured through the Enzyme-Linked Immunosorbent Assay (ELISA) technique. Two-hundred women (median age 35) were enrolled: 132 (66%) had received at least one dose of pertussis vaccine, 82 of which during pregnancy. Recently vaccinated women had significantly higher antibody titres (even 12–15 times as high) compared to those vaccinated more than 5 years before or never vaccinated at all (p < 0.0001). Moreover, 95.1% of recently vaccinated women had anti-PT IgG levels above 10 IU/ml, and 85.4% above 20 IU/ml, while the same proportions were as low as 37% and 21% (respectively) in the group of women not vaccinated in pregnancy. This study confirmed that the vaccination is greatly effective in ensuring high antibody titres in the first months after the booster vaccine, with considerable differences in anti-PT IgG compared to women vaccinated earlier or never vaccinated at all, and therefore vaccinating pregnant women against pertussis still represents a valuable strategy. [ABSTRACT FROM AUTHOR]