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Respiratory syncytial virus (RSV) causes acute respiratory infections. Rapid RSV diagnosis has an impact on patient management. In a newly developed molecular assay, named reverse transcription strand invasion based amplification (RT-SIBA) RSV assay, RSV RNA is reverse transcribed to cDNA and amplified and detected under isothermal reaction conditions. The performance of this assay was evaluated. Respiratory samples that tested positive (n = 81) or negative (n = 61) for RSV with the multiplex RT-PCR Anyplex II RV16 Detection Kit (Anyplex) were analyzed with the RT-SIBA assay. Discordant samples were tested with the GeneXpert Flu/RSV XC assay. Consistent results in at least 2 of the 3 methods were defined as reference standard. The RT-SIBA assay yielded a negative result for the 61 negative samples and a positive result in 71/81 (85.5%) of the Anyplex positive samples. After a resolution of discordant samples, the positive and negative percent agreement of the RT-SIBA assay were 92% and 100%, respectively. The RT-SIBA assay is a rapid molecular assay for the detection of RSV with good performance in clinical specimens. [ABSTRACT FROM AUTHOR]

Comparability between CMV assays could be facilitated by the first WHO International Standard for human CMV (standard). Standard dilutions were submitted to nucleic acid extraction with Versant kPCR Molecular systems SP or MagNA Pure LC System followed by the kPCR PLX™ CMV DNA (kPCR) or the CMV R-gene™ assay (R-gene), respectively; 139 clinical specimens were tested. Both assays correlated well with the standard ( R 2 > 0.96) and a matrix effect was observed. Quantitative results correlated reasonably between both assays for whole blood ( R 2 = 0.79) and well for other specimen types ( R 2 = 0.93). Quantification differences were within one log 10 of the averaged log 10 results for 25/27 blood specimens and for 32/33 other specimens. Calibration to the standard did not increase this percentage. In conclusion, results of both assays showed reasonable correlation with each other and good correlation with the standard. Calibration to the standard did not improve comparability of quantitative results. [ABSTRACT FROM AUTHOR]

While using the Xpert Flu assay we became aware of false-negative results. The study aimed to analyze the causes of these false-negative results. One hundred fifty-nine respiratory specimens were tested in the Xpert Flu assay and in multiplex reverse transcription–polymerase chain reactions (RT-PCRs) for respiratory viruses. Discordant specimens were tested in the Influenza A/B r-gene assay. One hundred fifty-two (96%) and 151 (95%) specimens yielded concordant results for influenza A and B, respectively. Fifteen specimens tested negative in the Xpert Flu assay and positive in a multiplex RT-PCR. Positive results were confirmed for 12 of these specimens in the Influenza A/B r-gene assay. Xpert Flu assay amplification curves and endpoints suggested that the false-negative results were mainly due to erroneous automatic result interpretation. We report false-negative results of the Xpert Flu assay due to erroneous automatic result interpretation. Careful analysis of amplification curves and endpoints is needed to avoid reporting of false-negative results. [ABSTRACT FROM AUTHOR]

We investigated serum neutralizing activity against BA.1 and BA.2 Omicron sublineages and T cell response before and 3 months after administration of the booster vaccine in healthcare workers (HCWs). HCWs aged 18–65 years who were vaccinated and received booster doses of the BNT162b2 vaccine were included. Anti–SARS coronavirus 2 IgG levels and cellular response (through interferon γ ELISpot assay) were evaluated in all participants, and neutralizing antibodies against Delta, BA.1, and BA.2 were evaluated in participants with at least one follow-up visit 1 or 3 months after the administration of the booster dose. Among 118 HCWs who received the booster dose, 102 and 84 participants attended the 1-month and 3-month visits, respectively. Before the booster vaccine dose, a low serum neutralizing activity against Delta, BA.1, and BA.2 was detectable in only 39/102 (38.2%), 8/102 (7.8%), and 12/102 (11.8%) participants, respectively. At 3 months, neutralizing antibodies against Delta, BA.1, and BA.2 were detected in 84/84 (100%), 79/84 (94%), and 77/84 (92%) participants, respectively. Geometric mean titres of neutralizing antibodies against BA.1 and BA.2 were 2.2-fold and 2.8-fold reduced compared with those for Delta. From 1 to 3 months after the administration of the booster dose, participants with a recent history of SARS coronavirus 2 infection (n = 21/84) had persistent levels of S1 reactive specific T cells and neutralizing antibodies against Delta and BA.2 and 2.2-fold increase in neutralizing antibodies against BA.1 (p 0.014). Conversely, neutralizing antibody titres against Delta (2.5-fold decrease, p < 0.0001), BA.1 (1.5-fold, p 0.02), and BA.2 (2-fold, p < 0.0001) declined from 1 to 3 months after the administration of the booster dose in individuals without any recent infection. The booster vaccine dose provided significant and similar response against BA.1 and BA.2 Omicron sublineages; however, the immune response declined in the absence of recent infection. [ABSTRACT FROM AUTHOR]

Pilgrims travelling to Saudi Arabia are commonly infected with respiratory viruses. Since the Middle East Respiratory Syndrome Coronavirus (MERS-CoV) emerged in 2012, patients with acute respiratory symptoms returning from an endemic area can be suspected to be infected by this virus. Methods: 98 patients suspected to have MERS-CoV infection from 2014 to 2019 were included in this retrospective cohort study. Upper and lower respiratory tract samples were tested by real-time RT-PCR for the detection of MERS-CoV and other respiratory viruses. Routine microbiological analyses were also performed. Patient data were retrieved from laboratory and hospital databases retrospectively. Results: All patients with suspected MERS-CoV infection travelled before their hospitalization. Most frequent symptoms were cough (94.4%) and fever (69.4%). 98 specimens were tested for MERS-CoV RNA and none of them was positive. Most frequently detected viruses were Enterovirus/Rhinovirus (40/83; 48.2%), Influenzavirus A (34/90; 37.8%) and B (11/90; 12.2%), H-CoV (229E and OC43 10/83; 12% and 7/83; 8.4%, respectively). Conclusion: From 2014 to 2019, none of 98 patients returning from endemic areas was MERS-CoV infected. However, infections with other respiratory viruses were frequent, especially with Enterovirus/Rhinoviruses and Influenzaviruses. • Most frequent symptoms leading to MERS-CoV infection suspicion were cough and fever. • No MERS-CoV detected in travelers returning from Middle East from 2014 to 2019. • Most frequently detected viruses were Enterovirus/Rhinovirus, Influenzavirus A and B. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 infections after COVID-19 vaccination are not unexpected, but those occurring more than 14 days after second vaccine dose need to be investigated. We describe a well-characterized infection which occurred almost 2 months after full vaccination, and provide the evidence of a link with a lack of anti-SARS-CoV-2 neutralizing antibodies. [ABSTRACT FROM AUTHOR]

Abstract: The detection of hepatitis B virus (HBV) infection markers by using dried plasma spots from 32 patients living in Congo has been assessed. Considering frozen plasma samples as gold standard, the sensitivity and specificity of HBV serologic markers detection in dried plasma eluted from filter paper were 100%. The sensitivity and the specificity of HBV DNA detection reached 96% and 100%, respectively, with plasma samples dried on filter paper compared to standard samples. Dried plasma samples can represent an alternative to conventional sampling for HBV detection and management of the infection in developing countries. [Copyright &y& Elsevier]

Diagnosis of hepatitis E virus (HEV) infection relies first on detection of IgM antibodies (Ab), sometimes completed with HEV RNA detection. This study aimed to compare the performance of two automated anti-HEV IgM Ab assays. Correlation between Virclia® (Vircell) and Liaison® (Diasorin) assays was carried out on 178 routine clinical samples. Both assays were run on 67 samples from HEV RT-PCR (Altona) screened patients, and 52 Wantai® EIA (Euroimmun) tested samples. An excellent correlation was observed between both assays with an overall agreement of 96.6% (172/178), and a kappa coefficient at 0.93. In HEV RNA positive group (n= 43), IgM detection rate was 93.3% (14/15) in immunocompetent patients, with both assays. In immunocompromised patients, detection rate was 75% (21/28) and 71.4% (20/28) using Virclia® and Liaison XL® assays, respectively. Virclia® and Liaison® anti-HEV IgM assays have similar performance for the detection of anti-HEV IgM Ab. [Display omitted] [ABSTRACT FROM AUTHOR]

The event of anti-CD19 chimeric antigen receptor (CAR)-T therapy inducing serious neurotoxicity in patients with diffuse large B-cell lymphoma (DLBCL) is recognized; however, the patterns of symptoms and severity vary greatly from patient to patient. We report an exceptional presentation of acute myelopathy in a refractory DLBCL following successful CAR-T treatment along with grade 3 cytokine release syndrome (CRS) and neurotoxicity. The patient was initiated on high-dose methylprednisolone (MPS) resulting in rapid improvement of neurological symptoms. Yet the myelopathy patient (MP) experienced severe lower limb motor deficit, and a subsequent spinal cord MRI revealed myelopathy with a sensory level at segment T2. Multimodal therapy consisting of MPS, intravenous immunoglobulin and anakinra therapy resulted in complete reversal of myelopathy condition and the patient remained cancer free. The assessment of time trends of serum cytokines at baseline and post CAR-T infusion in MP compared to other 4 DLBCL complete responder patients with varying degree of CRS following CAR-T infusion, suggested pre-existing baseline inflammatory conditions in MP with altered levels of cytokines. These findings, if corroborated by similar case studies, have the potential to generate novel insights into the manifestation of myelopathy following CAR-T therapy and the successful clinical management of such complications. [ABSTRACT FROM AUTHOR]