Detection of antibodies against SARS-CoV-2 both in plasma pools for fractionation and in commercial intravenous immunoglobulins produced from plasma collected in Italy during the pandemic.

BACKGROUND: We investigated the presence of anti-SARS-CoV-2 antibodies in Italian plasma pools and intravenous immunoglobulins sent to our Institute (Italian National Institute of Health - Istituto Superiore di Sanità) in the context of the Official Control Authority Batch Release. The plasma pools were made up from donations collected in several different Italian regions from May 2017 to October 2020, i.e. in the pre-pandemic and pandemic periods. MATERIALS AND METHODS: All plasma pools were initially tested for the qualitative detection of anti-SARS-CoV-2 antibodies against the nucleocapsid protein using the Roche Elecsys® Anti-SARS-CoV-2 test kit. Plasma pools positive for these antibodies were further tested using the Roche Elecsys® Anti-SARS-CoV-2 S test kit for the quantitative detection of antibodies against SARS-CoV-2 spike receptor binding domain. All plasma pools showing reactivity to these antibodies were tested undiluted for the presence of SARS-CoV-2 RNA using the Grifols Procleix SARS-CoV-2 transcription-mediated amplification assay. Intravenous immunoglobulins were tested using both test kits to determine the presence of anti-SARS-CoV-2 antibodies. RESULTS: All plasma pools made up from donations collected in the pre-pandemic period were negative for anti-SARS-CoV-2 antibodies against the nucleocapsid protein. Of the plasma pools made up from donations collected from December 2018 to March 2020, only 1 pool out of 68 (1.4%), that was made up from donations from the Lombardy region, was reactive for these antibodies. Interestingly, 105 out of 174 (60.3%) of the plasma pools made up from donations collected from November 2018 to October 2020 showed the presence of these antibodies. All plasma pools positive for these antibodies were tested for antibodies against SARS-CoV-2 spike receptor binding domain and were confirmed positive. DISCUSSION: None of these plasma pools tested were reactive for SARS-CoV-2 RNA. In the case of intravenous immunoglobulins, 20 out of 25 (80%) batches showed the presence of both anti-SARS-CoV-2 antibodies, reflecting the concentration in the plasma pools used for their production.

Poliovirus and Other Enteroviruses from Environmental Surveillance in Italy, 2009-2015.

Within the initiatives for poliomyelitis eradication by WHO, Italy activated an environmental surveillance (ES) in 2005. ES complements clinical Acute Flaccid Paralysis (AFP) surveillance for possible polio cases, detects poliovirus circulation in environmental sewage, and is used to monitor transmission in communities. In addition to polioviruses, the analyses comprised: (i) the monitoring of the presence of non-polio enteroviruses in sewage samples and (ii) the temporal and geographical distribution of the detected viruses. From 2009 to 2015, 2880 sewage samples were collected from eight cities participating in the surveillance. Overall, 1479 samples resulted positive for enteroviruses. No wild-type polioviruses were found, although four Sabin-like polioviruses were detected. The low degree of mutation found in the genomes of these four isolates suggests that these viruses have had a limited circulation in the population. All non-polio enteroviruses belonged to species B and the most frequent serotype was CV-B5, followed by CV-B4, E-11, E-6, E-7, CV-B3, and CV-B2. Variations in the frequency of different serotypes were also observed in different seasons and/or Italian areas. Environmental surveillance in Italy, as part of the 'WHO global polio eradication program', is a powerful tool to augment the polio surveillance and to investigate the silent circulation or the re-emergence of enteroviruses in the population.

West Nile Virus in Europe and Safety of Blood Transfusion.

West Nile virus (WNV) has become an increasing issue in the transfusion setting since 2002, when it was firstly shown in the USA that it can be transmitted through blood transfusion. Since then, several precautionary measures have been introduced in Europe in order to reduce the possible risk of transmission via transfusion/solid organ transplantation. In addition, the epidemiological surveillance has been tightened and the network for communication of human WNV cases strengthened. This review will focus on WNV circulation and the safety of blood in Europe.

Detection of West Nile virus RNA (lineages 1 and 2) in an external quality assessment programme for laboratories screening blood and blood components for West Nile virus by nucleic acid amplification testing.

BACKGROUND: A second Italian external quality assessment programme was run in 2011 to assess the performance of blood transfusion centres in detecting West Nile virus RNA in plasma. MATERIALS AND METHODS: Each participant received two panels containing negative samples and samples positive for West Nile virus lineages 1 and 2, some of which with a viral concentration close to or below the 95% limit of detection of the respective commercial nucleic acid amplification test assay: the PROCLEIX WNV assay or the Cobas TaqScreen West Nile virus test. RESULTS: Eleven laboratories took part in the external quality assessment programme. All of them correctly identified the positive samples with a viral concentration above the 95% limit of detection. No false positive results or pre-/post-analytical errors were observed. DISCUSSION: The External quality assessment programme run in 2011 allowed participants to assess the performance of the nucleic acid amplification test methods applied in their seasonal routine screening of blood donations. The results confirm the 95% limit of detection reported by the test kits' manufacturers for both West Nile virus lineages.

Quantification of hepatitis C virus (HCV) RNA in a multicenter study: implications for management of HCV genotype 1-infected patients.

Assessment of the viral load in hepatitis C virus (HCV) genotype 1-infected patients is critical before, during, and after antiviral therapy. In patients achieving a rapid virological response at week 4 of treatment, the viral load at the baseline is considered a predictive criterion of a sustained virological response 24 weeks after the discontinuation of treatment. A >or=2-log(10) drop in the viral load at week 12 of treatment (early virological response) triggers the continuation of therapy. We organized a multicenter study (MS) for diagnostic laboratories involved in the quantification of HCV RNA. Commercial assays, including two based on real-time reverse transcription-PCR (TaqMan system), and in-house methods, were used by the 61 participants. The overall reproducibility of the commercial quantitative nucleic acid amplification techniques (qNAT) was acceptable. As the intermethod variability among commercial qNAT for HCV RNA was still present, the manufacturers of these test kits should join efforts to harmonize the means of quantification of HCV RNA. This study also shows that caution should be exercised when the baseline viral load is evaluated and when the 2-log(10) reduction after 12 weeks of therapy is interpreted. Finally, this MS confirms the higher sensitivity of the commercial qNAT based on the TaqMan system, making them the elective assays for the monitoring of therapy.

Collaborative study for the calibration of HCV RNA, HBV DNA and HIV RNA reference preparations against the relative international standards.

We organised a collaborative study to calibrate three new ISS reference preparations (ISS: Istituto Superiore di Sanità), one for HCV RNA, one for HIV RNA and one for HBV DNA, to be used for nucleic acid amplification techniques (NAT) in blood testing. Serial dilution of the ISS reference preparations and the respective international standards were tested in different days by each participating laboratory using two commercial NAT assays. Data were collected by the ISS for statistical analysis. Based on the mean potency of the HCV RNA and HIV RNA preparations, calculated from the results provided by the 12 participating laboratories, a definitive concentrations of 5700 IU/mL and 4000 IU/mL, respectively, were assigned to the reference materials. On the contrary, it was not possible to obtain a consensus titre for the HBV DNA reference material. These new Italian reference preparations (HCV RNA ISS/1005 and HIV RNA ISS/1005) calibrated against the respective international standards are available free of charge to any laboratory upon request.

Collaborative study for the calibration of a new Italian HCV RNA reference preparation against the international standard.

We organised a collaborative study to calibrate a new Italian reference preparation for HCV RNA, the ISS 0102 reagent, to be used for plasma pools testing. This preparation will replace the previous one, the ISS 0498 reagent, as we are running short of it. The ISS 0102 reagent was obtained by appropriately diluting an HCV RNA-positive donation. Every participant in the collaborative study received four coded panels, each consisting of 5 semi-logarithmic dilutions of the international standard, 5 semi-logarithmic dilutions of the ISS 0102, and 2 samples of a negative plasma pool. Based on the results provided by the 22 participating laboratories, an HCV RNA concentration of 4500 IU/ml was assigned to the reference material. This preparation is available free of charge to any laboratory upon request.

Overestimation of the hepatitis C virus RNA content of reference preparations by the AMPLICOR HCV monitor test, version 2.0.

An evaluation of the AMPLICOR hepatitis C virus (HCV) monitor test, version 2.0 (Roche Diagnostics), was carried out to investigate whether this test overestimates the HCV RNA content of reference preparations. Satisfactory accuracy was observed when the World Health Organization HCV international standard was included in the assay and a modified formula was used to calculate the viral content.