Transmitted drug resistance to antiretroviral drugs in Spain during the period 2019-2021.

To evaluate the prevalence of transmitted drug resistance (TDR) to nucleoside and nonnucleoside reverse transcriptase inhibitors (NRTI, NNRTI), protease inhibitors (PI), and integrase strand transfer inhibitors (INSTI) in Spain during the period 2019-2021, as well as to evaluate transmitted clinically relevant resistance (TCRR) to antiretroviral drugs. Reverse transcriptase (RT), protease (Pro), and Integrase (IN) sequences from 1824 PLWH (people living with HIV) were studied. To evaluate TDR we investigated the prevalence of surveillance drug resistance mutations (SDRM). To evaluate TCRR (any resistance level ≥ 3), and for HIV subtyping we used the Stanford v.9.4.1 HIVDB Algorithm and an in-depth phylogenetic analysis. The prevalence of NRTI SDRMs was 3.8% (95% CI, 2.8%-4.6%), 6.1% (95% CI, 5.0%-7.3%) for NNRTI, 0.9% (95% CI, 0.5%-1.4%) for PI, and 0.2% (95% CI, 0.0%-0.9%) for INSTI. The prevalence of TCRR to NRTI was 2.1% (95% CI, 1.5%-2.9%), 11.8% for NNRTI, (95% CI, 10.3%-13.5%), 0.2% (95% CI, 0.1%-0.6%) for PI, and 2.5% (95% CI, 1.5%-4.1%) for INSTI. Most of the patients were infected by subtype B (79.8%), while the majority of non-Bs were CRF02_AG (n = 109, 6%). The prevalence of INSTI and PI resistance in Spain during the period 2019-2021 is low, while NRTI resistance is moderate, and NNRTI resistance is the highest. Our results support the use of integrase inhibitors as first-line treatment in Spain. Our findings highlight the importance of ongoing surveillance of TDR to antiretroviral drugs in PLWH particularly with regard to first-line antiretroviral therapy.

Reduced neutralizing antibody response to SARS-CoV-2 vaccine booster dose in people living with HIV with severe immunosuppression.

The aim of this study was to assess the immunogenicity of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines among people living with HIV (PLWH) with severe immunosuppression, after a booster dose. The design was a case-control study nested in a prospective cohort of PLWH. All patients with CD4 cell count <200 cells/mm3 who had received additional dose of messenger RNA (mRNA) COVID-19 vaccine, after a standard immunization scheme were included. Control group: patients age- and sex-matched, with CD4 ≥ 200 cells/mm3 , in the ratio of 2:1. Antibody response to a booster dose (anti-S levels 33.8 ≥ BAU/mL) and neutralizing activity against SARS-CoV-2 B.1, B.1.617.2, and Omicron BA.1, BA.2, and BA.5 strains were assessed after the booster shot. Fifty-four PLWH were included, 18 with CD4 counts < 200 cells/mm3 . Fifty-one (94%) showed response to a booster dose. Response was less frequent in PLWH with CD4 < 200 cells/mm3 than in those with CD4 counts ≥ 200 cells/mm3 (15 [83%] vs. 36 [100%], p = 0.033). In the multivariate analysis, CD4 counts ≥ 200 cells/mm3 [incidence rate ratio (IRR) = 18.1 (95% confidence interval [CI]: 16.8-19.5), p < 0.001] was associated with a higher probability of showing antibody response. Neutralization activity against SARS-CoV-2 B.1, B.1.617, BA.1, and BA.2 strains was significantly inferior among individuals with CD4 counts < 200 cells/mm3 . In conclusion, among PLWH with CD4 counts < 200 cells/mm3 , the immune response elicited by mRNA additional vaccine dose is reduced.

Transmitted Drug Resistance to Integrase-Based First-Line Human Immunodeficiency Virus Antiretroviral Regimens in Mediterranean Europe.

BACKGROUND: We evaluated the prevalence of transmitted drug resistance (TDR) to integrase strand-transfer inhibitors (INSTIs) and nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) and of clinically relevant resistance (CRR) in newly diagnosed people with human immunodeficiency virus (HIV; PWH) naive to antiretroviral therapy (ART) in Europe. METHODS: MeditRes is a consortium that includes ART-naive PWH newly diagnosed in France, Greece, Italy, Portugal, and Spain during 2018-2021. Reverse transcriptase and INSTI sequences were provided by participating centers. To evaluate the prevalence of surveillance drug resistance mutations (SDRM), we used the calibrated population resistance tools from the Stanford HIV website. To evaluate CRR, defined as any resistance level ≥3, we used the Stanford HIV Drug Resistance Database v.9.1 algorithm. RESULTS: We included 2705 PWH, 72% men, median age of 37 years (interquartile range, 30-48); 43.7% were infected by non-B subtypes. The prevalence of INSTI-SDRMs was 0.30% (T66I, T66A, E92Q, E138T, E138K, Y143R, S147G, R263K; all n=1) and the prevalence of NRTI-SDRMs was 5.77% (M184V: 0.85%; M184I: 0.18%; K65R/N: 0.11%; K70E: 0.07%; L74V/I: 0.18%; any thymidine analog mutations: 4.36%). INSTI-CRR was 2.33% (0.15% dolutegravir/bictegravir, 2.29% raltegravir/elvitegravir) and 1.74% to first-line NRTIs (0.89% tenofovir/tenofovir alafenamide, 1.74% abacavir, 1.07% lamivudine/emtricitabine). CONCLUSIONS: We present the most recent data on TDR to integrase-based first-line regimens in Europe. Given the low prevalence of CRR to second-generation integrase inhibitors and to first-line NRTIs during 2018-2021, it is unlikely that newly diagnosed PWH in MeditRes countries would present with baseline resistance to a first-line regimen based on second-generation integrase inhibitors.

In vitro neutralizing activity of BNT162b2 mRNA-induced antibodies against full B.1.351 SARS-CoV-2 variant.

SARS-CoV-2 variation represents a serious challenge to current COVID-19 vaccines. Recent reports suggest that B.1.351 and other variants may escape the neutralization activity of the antibodies generated by current vaccines. Ninety-nine healthcare workers undertaking BNT162b2 mRNA vaccination were sampled at baseline, on the day of the second dose, and 14 days after the latter. Neutralization activity against SARS-CoV-2 B.1, B.1.1.7 and B.1.351 was investigated using a Vero-E6 model. Eleven of the study participants had prior infection with SARS-CoV-2. Neutralization titers against the B.1 and the B.1.1.7 variants were not statistically different and were significantly higher than titers against the B.1.351 variant across pre-exposed and non-pre-exposed vaccinated individuals (p < .01). While all vaccinated individuals presented neutralizing antibodies against B.1 and B 1.1.7 after the second dose, 14% were negative against B.1.351 and 76% had low titers (1/201/80). Pre-exposed vaccinated individuals showed higher titers than non-pre-exposed after the first (median titers of 1/387 versus 1/28, respectively) and the second doses (1/995 versus 1/703, respectively). As high as 72% of the pre-exposed vaccines presented titers >1/80 after a single dose, while only 11% of non-exposed vaccinated individuals had titers >1/80. BNT162b2 mRNA-induced antibodies show a lower in vitro neutralizing activity against B.1.351 variant compared to neutralization against B.1.1.7 or B.1 variants. Interestingly, for individuals pre-exposed to SARS-CoV-2, one dose of BNT162b2 mRNA may be adequate to produce neutralizing antibodies against B.1.1.7 and B.1, while two doses of BNT162b2 mRNA provide optimal neutralizing antibody response against B.1.351 too.

Comparison between Aptima® assays (Hologic) and the CoBAS® 6800 system (Roche) for the diagnosis of sexually transmitted infections caused by Chlamydia trachomatis, Neisseria gonorrhoeae, and Mycoplasma genitalium.

Nowadays, it is of utmost importance to use fully validated assays for molecular-based diagnosis. In the field of sexually transmitted disease (STD), Roche and Hologic provide assays for diagnosing Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Mycoplasma genitalium (MG), and Trichomonas vaginalis (TV). A total of 212 clinical samples were tested. Aptima® Combo 2 (detecting CT and NG), Aptima® M. genitalium and the Aptima® T. vaginalis on the Panther® system were compared to CoBAS® CT/NG and CoBAS® TV/MG running on the CoBAS® 6800 system. To solve the discrepancies, Allplex™ STI Essential assay (Seegene®) and/or Sanger DNA sequencing were used. The diagnostic performance was calculated by mean of the sensitivity and specificity parameters. Aptima® (sensitivity: 98.90%, specificity: 100%), CoBAS® (sensitivity 100%, specificity: 96.67%). The CoBAS® combo (CT/NG) failed detecting NG from an anal/rectum specimen, which is not included into the validated specimens of the assay. Aptima® combo 2 produced two false positives (CT and NG), not detected by the third tests. All the assays showed an optimal diagnostic capacity, meeting the requirements for IVD DNA-based assays. All products work optimally on automatic platforms, minimizing time and risk of contamination during handling.

Antibody response in patients admitted to the hospital with suspected SARS-CoV-2 infection: results from a multicenter study across Spain.

AIM: To evaluate the serological response against SARS-CoV-2 in a multicenter study representative of the Spanish COVID pandemic. METHODS: IgG and IgM + IgA responses were measured on 1466 samples from 1236 Spanish COVID-19 patients admitted to the hospital, two commercial ELISA kits (Vircell SL, Spain) based on the detection of antibodies against the viral spike protein and nucleoprotein, were used. RESULTS: Approximately half of the patients presented antibodies (56.8% were IgM + IgA positive and 43.0% were IgG positive) as soon as 2 days after the first positive PCR result. Serological test positivity increased with time from the PCR test, and 10 days after the first PCR result, 91.5% and 88.0% of the patients presented IgM + IgA and IgG antibodies, respectively. CONCLUSION: The high values of sensitivity attained in the present study from a relatively early period of time after hospitalization support the use of the evaluated serological assays as supplementary diagnostic tests for the clinical management of COVID-19.

Sample pooling for SARS-CoV-2 RT-PCR screening.

OBJECTIVE: To evaluate the efficacy of sample pooling compared to the individual analysis for the diagnosis of coronavirus disease 2019 (COVID-19) by using different commercial platforms for nucleic acid extraction and amplification. METHODS: A total of 3519 nasopharyngeal samples received at nine Spanish clinical microbiology laboratories were processed individually and in pools (342 pools of ten samples and 11 pools of nine samples) according to the existing methodology in place at each centre. RESULTS: We found that 253 pools (2519 samples) were negative and 99 pools (990 samples) were positive; with 241 positive samples (6.85%), our pooling strategy would have saved 2167 PCR tests. For 29 pools (made out of 290 samples), we found discordant results when compared to their correspondent individual samples, as follows: in 22 of 29 pools (28 samples), minor discordances were found; for seven pools (7 samples), we found major discordances. Sensitivity, specificity and positive and negative predictive values for pooling were 97.10% (95% confidence interval (CI), 94.11-98.82), 100%, 100% and 99.79% (95% CI, 99.56-99.90) respectively; accuracy was 99.80% (95% CI, 99.59-99.92), and the kappa concordant coefficient was 0.984. The dilution of samples in our pooling strategy resulted in a median loss of 2.87 (95% CI, 2.46-3.28) cycle threshold (Ct) for E gene, 3.36 (95% CI, 2.89-3.85) Ct for the RdRP gene and 2.99 (95% CI, 2.56-3.43) Ct for the N gene. CONCLUSIONS: We found a high efficiency of pooling strategies for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA testing across different RNA extraction and amplification platforms, with excellent performance in terms of sensitivity, specificity and positive and negative predictive values.