T-Cell Immune Responses in Newborns and Long-Term Sequelae in Congenital Cytomegalovirus Infection (CYTRIC Study).

OBJECTIVE: The objective of this study was to assess the role of T-lymphocyte immune responses in newborns with congenital cytomegalovirus (CMV) infection (cCMV) and their potential association with the development of long-term sequelae. STUDY DESIGN: A multicenter, prospective study from 2017 to 2022 was conducted across 8 hospitals in Spain. Blood samples were collected within the first month of life from neonates diagnosed with cCMV. Intracellular cytokine staining was employed to evaluate the presence of CMV-specific interferon-gamma (IFN-γ)-producing CD8+ and CD4+ T lymphocytes (CMV-IFN-γ-CD8+/CD4+) using flow cytometry. The development of sequelae, including hearing loss and neurologic impairment, was assessed during follow-up. RESULTS: In total, 64 newborns were included; 42 infants (65.6%) had symptomatic cCMV. The median age at the last follow-up visit was 25.3 months (IQR 20.1-34.4). Eighteen infants had long-term sequelae (28.1%), predominantly hearing loss (20.3%) and neurologic disorders (15.6%). No relationship was observed between total count or percentage of CMV-specific IFN-γ-CD8+ or CD4+ lymphocytes and long-term sequelae. Multivariable analysis demonstrated an association between lower total lymphocyte count and long-term sequelae (aOR 0.549, 95% CI: 0.323-0.833), which requires further study. CONCLUSIONS: CMV-specific IFN-γ-CD4+ and CD8+ T-lymphocyte responses in neonates with cCMV were not predictive of long-term sequelae.

Severe Presentation of Mpox With Skin, Lung and Pleural Involvement in a Non-HIV-Infected Kidney Transplant Recipient.

Monkeypox (mpox) is an orthopoxviral zoonotic disease with a similar but less severe clinical presentation as smallpox. However, immunocompromised patients such as solid organ transplant recipients are at higher risk of developing severe forms of the disease. Herein, we describe the case of a 43-year-old female kidney transplant recipient that manifested severe skin ulcers alongside nodular lung opacities and pleural effusion attributed directly to the monkeypox virus. Notwithstanding the initiation of early treatment with tecovirimat, a satisfactory response was not achieved until a reduction in immunosuppression to everolimus monotherapy, coupled with the transition to cidofovir for antiviral treatment. In conclusion, mpox has the potential to produce a severe form of systemic infection in individuals who have undergone solid organ transplantation, demanding a meticulous approach involving sequential antiviral treatment and modifications to immunosuppressive regimens in order to achieve complete healing.

Evaluating the Accuracy of Self-Collected Swabs for the Diagnosis of Mpox.

We evaluated the accuracy of patient-collected skin lesions, oropharyngeal, and rectal swabs among 50 individuals enrolled in a study of mpox viral dynamics. We found that the performance of self-collected samples was similar to that of physician-collected samples, suggesting that self-sampling is a reliable strategy for diagnosing mpox.

Clinical presentation and virological assessment of confirmed human monkeypox virus cases in Spain: a prospective observational cohort study.

BACKGROUND: In May, 2022, several European countries reported autochthonous cases of monkeypox, which rapidly spread globally. Early reports suggest atypical presentations. We aimed to investigate clinical and virological characteristics of cases of human monkeypox in Spain. METHODS: This multicentre, prospective, observational cohort study was done in three sexual health clinics in Madrid and Barcelona, Spain. We enrolled all consecutive patients with laboratory-confirmed monkeypox from May 11 to June 29, 2022. Participants were offered lesion, anal, and oropharynx swabs for PCR testing. Participant data were collected by means of interviews conducted by dermatologists or specialists in sexually transmitted infections and were recorded using a standard case report form. Outcomes assessed in all participants with a confirmed diagnosis were demographics, smallpox vaccination, HIV status, exposure to someone with monkeypox, travel, mass gathering attendance, risk factors for sexually transmitted infections, sexual behaviour, signs and symptoms on first presentation, virological results at multiple body sites, co-infection with other sexually transmitted pathogens, and clinical outcomes 14 days after the initial presentation. Clinical outcomes were followed up until July 13, 2022. FINDINGS: 181 patients had a confirmed monkeypox diagnosis and were enrolled in the study. 166 (92%) identified as gay men, bisexual men, or other men who have sex with men (MSM) and 15 (8%) identified as heterosexual men or heterosexual women. Median age was 37·0 years (IQR 31·0-42·0). 32 (18%) patients reported previous smallpox vaccination, 72 (40%) were HIV-positive, eight (11%) had a CD4 cell count less than 500 cells per µL, and 31 (17%) were diagnosed with a concurrent sexually transmitted infection. Median incubation was 7·0 days (IQR 5·0-10·0). All participants presented with skin lesions; 141 (78%) participants had lesions in the anogenital region, and 78 (43%) in the oral and perioral region. 70 (39%) participants had complications requiring treatment: 45 (25%) had a proctitis, 19 (10%) had tonsillitis, 15 (8%) had penile oedema, six (3%) an abscess, and eight (4%) had an exanthem. Three (2%) patients required hospital admission. 178 (99%) of 180 swabs from skin lesions collected tested positive, as did 82 (70%) of 117 throat swabs. Viral load was higher in lesion swabs than in pharyngeal specimens (mean cycle threshold value 23 [SD 4] vs 32 [6], absolute difference 9 [95% CI 8-10]; p<0·0001). 108 (65%) of 166 MSM reported anal-receptive sex. MSM who engaged in anal-receptive sex presented with proctitis (41 [38%] of 108 vs four [7%] of 58, absolute difference 31% [95% CI 19-44]; p<0·0001) and systemic symptoms before the rash (67 [62%] vs 16 [28%], absolute difference 34% [28-62]; p<0·0001) more frequently than MSM who did not engage in anal-receptive sex. 18 (95%) of 19 participants with tonsillitis reported practising oral-receptive sex. The median time from onset of lesions to formation of a dry crust was 10 days (IQR 7-13). INTERPRETATION: In our cohort, monkeypox caused genital, perianal, and oral lesions and complications including proctitis and tonsillitis. Because of the variability of presentations, clinicians should have a low threshold for suspicion of monkeypox. Lesion swabs showed the highest viral loads, which, combined with the history of sexual exposure and the distribution of lesions, suggests close contact is probably the dominant transmission route in the current outbreak. FUNDING: None.

Cross neutralization of SARS-CoV-2 omicron subvariants after repeated doses of COVID-19 mRNA vaccines.

We have measured the humoral response to messenger RNA (mRNA) vaccines in COVID-19 naïve and convalescent individuals. Third doses of mRNA COVID-19 vaccines induced a significant increase in potency and breadth of neutralization against SARS-CoV-2 variants of concern (VoC) including Omicron subvariants BA.1, BA.2, and BA.2.12.1, that were cross-neutralized at comparable levels and less for BA.4/5. This booster effect was especially important in naïve individuals that only after the third dose achieved a level that was comparable with that of vaccinated COVID-19 convalescents except for BA.4/5. Avidity of RBD-binding antibodies was also significantly increased in naïve individuals after the third dose, indicating an association between affinity maturation and cross neutralization of VoC. These results suggest that at least three antigenic stimuli by infection or vaccination with ancestral SARS-CoV-2 sequences are required to induce high avidity cross-neutralizing antibodies. Nevertheless, the circulation of new subvariants such as BA.4/5 with partial resistance to neutralization will have to be closely monitored and eventually consider for future vaccine developments.

Superior neutralizing response after first versus second SARS-CoV-2 infection in fully vaccinated individuals.

Currently, the majority of the population has been vaccinated against COVID-19 and/or has experienced SARS-CoV-2 infection either before or after vaccination. The immunological response to repeated episodes of infections is not completely clear. We measured SARS-CoV-2 specific neutralization titers by a pseudovirus assay after BA.1 infection and RBD-specific immunoglobulin G (IgG), immunoglobulin A (IgA), and immunoglobulin M (IgM) in a cohort of COVID-19 uninfected and triple vaccinated individuals (breakthrough infection group, BTI) as compared with those previously infected by SARS-CoV-2 (reinfection group, REI) who underwent identical vaccination schedule. SARS-CoV-2 specific neutralizing response after BA.1 infection was significantly higher in the BTI group as compared with the REI. Furthermore, neutralization titers in REI were not significant different from convalescent non reinfected controls. RBD-specific IgG and IgA, but not IgM, were also significantly higher in BTI as compared with REI. Our results show that the first episode of SARS-CoV-2 infection induces a significant increase in neutralizing titers in triple vaccinated individuals and that previous SARS-CoV-2 infection compromise significantly the neutralization response induced by reinfection, even by divergent SARS-CoV-2 variants and at least up to 2 years postinfection, suggesting a fundamental limitation in inducing effective booster through the intranasal route in previously infected individuals.

Clinical outcomes and antibody transfer in a cohort of infants with in utero or perinatal exposure to SARS-CoV-2 (Coronascope Study).

We aimed to describe the outcomes, focusing on the hearing and neurological development, of infants born to mothers with COVID-19 during pregnancy and to evaluate the persistence of maternal antibodies in the first months of life. An observational, prospective study at a tertiary hospital in Madrid (Spain) on infants born to mothers with COVID-19 during pregnancy between March and September 2020 was conducted. A follow-up visit at 1-3 months of age with a physical and neurological examination, cranial ultrasound (cUS), SARS-CoV-2 RT-PCR on nasopharyngeal swab, and SARS-CoV-2 serology were performed. Hearing was evaluated at birth through the automated auditory brainstem response and at six months of age through the auditory steady-state response. A neurodevelopmental examination using the Bayley-III scale was performed at 12 months of age. Of 95 infants studied, neurological examination was normal in all of them at the follow-up visit, as was the cUS in 81/85 (95%) infants, with only mild abnormalities in four of them. Serology was positive in 47/95 (50%) infants, which was not associated with symptoms or severity of maternal infection. No hearing loss was detected, and neurodevelopment was normal in 96% of the infants (median Z score: 0). CONCLUSION: In this cohort, the majority of infants born to mothers with COVID-19 during pregnancy were healthy infants with a normal cUS, no hearing loss, and normal neurodevelopment in the first year of life. Only half of the infants had a positive serological result during the follow-up. WHAT IS KNOWN: • Hearing loss and neurodevelopmental delay in infants born to mothers with COVID-19 during pregnancy has been suggested, although data is inconsistent. Maternal antibody transfer seems to be high, with a rapid decrease during the first weeks of life. WHAT IS NEW: • Most infants born to mothers with COVID-19 during pregnancy had normal hearing screening, cranial ultrasound, and neurodevelopmental status at 12 months of life. Antibodies against SARS-CoV-2 were only detected in 50% of the infants at two months of life.

Enhancing SARS-CoV-2 Surveillance through Regular Genomic Sequencing in Spain: The RELECOV Network.

Millions of SARS-CoV-2 whole genome sequences have been generated to date. However, good quality data and adequate surveillance systems are required to contribute to meaningful surveillance in public health. In this context, the network of Spanish laboratories for coronavirus (RELECOV) was created with the main goal of promoting actions to speed up the detection, analyses, and evaluation of SARS-CoV-2 at a national level, partially structured and financed by an ECDC-HERA-Incubator action (ECDC/GRANT/2021/024). A SARS-CoV-2 sequencing quality control assessment (QCA) was developed to evaluate the network's technical capacity. QCA full panel results showed a lower hit rate for lineage assignment compared to that obtained for variants. Genomic data comprising 48,578 viral genomes were studied and evaluated to monitor SARS-CoV-2. The developed network actions showed a 36% increase in sharing viral sequences. In addition, analysis of lineage/sublineage-defining mutations to track the virus showed characteristic mutation profiles for the Delta and Omicron variants. Further, phylogenetic analyses strongly correlated with different variant clusters, obtaining a robust reference tree. The RELECOV network has made it possible to improve and enhance the genomic surveillance of SARS-CoV-2 in Spain. It has provided and evaluated genomic tools for viral genome monitoring and characterization that make it possible to increase knowledge efficiently and quickly, promoting the genomic surveillance of SARS-CoV-2 in Spain.

Neutralizing Response Against SARS-CoV-2 Variants 8 Months After BNT162b2 Vaccination in Naive and COVID-19-Convalescent Individuals.

We have investigated the evolution of the neutralizing response against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants at 8 months after Pfizer-BNT162b2 vaccination in coronavirus disease 2019 (COVID-19)-naive (n = 21) and COVID-19-convalescent (n = 21) individuals. Neutralizing levels declined for all variants (range 2- to 3.7-fold). Eight months after vaccination, a significant proportion (4/21) of naive individuals lacked detectable neutralizing activity against the highly transmissible SARS-CoV-2 delta variant. In the convalescent group, the impressive high initial humoral response resulted in detectable neutralizing antibody levels against all variants throughout this period.

Cytomegalovirus Exposure and the Risk of Overall Infection After Kidney Transplantation: A Cohort Study on the Indirect Effects Attributable to Viral Replication.

Previous reports hypothesized that cytomegalovirus (CMV) may predispose to non-CMV infection after kidney transplantation (KT). We analysed the incidence of non-CMV infection (overall, bacterial and opportunistic) in 291 KT recipients according to the previous development of any level or high-level (≥1,000 IU/ml) CMV viremia. Exposure to CMV replication was assessed throughout fixed intervals covering first the 30, 90, 180 and 360 post-transplant days (cumulative exposure) and non-overlapping preceding periods (recent exposure). Adjusted Cox models were constructed for each landmark analysis. Overall, 67.7 and 50.5% patients experienced non-CMV and CMV infection, respectively. Patients with cumulative CMV exposure had higher incidence of non-CMV infection beyond days 30 (p-value = 0.002) and 90 (p-value = 0.068), although these associations did not remain after multivariable adjustment. No significant associations were observed for the remaining landmark models (including those based on high-level viremia or recent CMV exposure), or when bacterial and opportunistic infection were separately analysed. There were no differences in viral kinetics (peak CMV viremia and area under curve of CMV viral load) either. Our findings do not support the existence of an independent association between previous CMV exposure and the overall risk of post-transplant infection, although results might be affected by power limitations.

Detection of BK polyomavirus genotypes to predict the development of BK polyomavirus-associated complications in kidney transplant recipients: A retrospective analysis.

OBJECTIVES: This study focused on the role that BK polyomavirus (BKPyV) genotypes can play in the development of BKPyV-associated complications in renal transplant recipients. METHODS: A retrospective observational study (January 2015 to April 2018) was conducted by analyzing BKPyV genotypes in 180 blood samples with detectable BKPyV viral load (VL) > 1000 copies/mL, from 63 renal transplant recipients. VL and BKPyV genotypes detections were based on real-time PCR (rt-PCR)-specific assays. RESULTS: Forty-four patients (44/63 [69.8%]) were men, and the median age was 55.0 (interquartile range 49.0-66.0 years). Eleven patients had clinical manifestations (11/63 [17.5%]). The most frequently detected genotypes were I (14/63 [22.2%]) and II (13/63 [20.6%]). Half of the patients (33/63 [52.4%]) had a mixed genotype, most with genotypes I and II (25/33 [75.8%]). Patients with infection by mixed genotypes showed VLs that were detected earlier (in the first year after transplantation) than those with a single genotype (25/33 [75.8%] vs 13/30 [43.3%], P = .009) and demonstrated greater risk of developing clinical manifestations associated with BKPyV (odds ratio 12.609, 95% confidence interval 1.503-105.807). Moreover, patients with first BKPyV VL > 10 000 copies/mL more frequently presented mixed genotypes (12/16 [75.0%] vs 21/47 [44.7%], P = .036). CONCLUSIONS: The probability of developing clinical manifestations is higher in infections by mixed genotypes. Therefore, the detection of BKPyV genotypes by rt-PCR can provide relevant information to stratify patients' risk of BKPyV-associated complications and guide the clinical management of BKPyV infection in kidney transplant recipients.

Monitoring of CMV-specific cell-mediated immunity with a commercial ELISA-based interferon-γ release assay in kidney transplant recipients treated with antithymocyte globulin.

Monitoring for cytomegalovirus (CMV)-specific cell-mediated immunity (CMV-CMI) may be useful for individualizing valganciclovir (VGCV) prophylaxis after kidney transplantation (KT). We performed a commercial ELISA-based interferon (IFN)-γ release assay (QTF-CMV) from posttransplant months 2-5 (362 points) in 120 CMV-seropositive KT recipients that received antithymocyte globulin as induction therapy and VGCV prophylaxis (median of 92 days). Forty-seven patients (39.3%) had CMV infection after discontinuation of prophylaxis. The QTF-CMV assay was reactive, nonreactive, and indeterminate in 264 (72.9%), 90 (24.9%), and 8 points (2.2%). The QTF-CMV assay at prophylaxis discontinuation exhibited suboptimal accuracy for predicting protective CMV-CMI (sensitivity: 77.4%; specificity: 34.3%; positive predictive value [PPV]: 64.1%; negative predictive value [NPV]: 50.0%), with no differences in 1-year CMV infection rates between patients with negative (nonreactive or indeterminate) or reactive results (45.8% vs 36.1%; P = .244). Specificity and PPV to predict protective CMV-CMI improved by elevating the IFN-γ cutoff value to 1.13 IU/mL (65.7% and 71.4%) and 7.0 IU/mL (85.7% and 76.2%), although NPVs decreased. The QTF-CMV assay as per manufacturer's interpretative criteria performed poorly to predict protection from CMV infection following discontinuation of VGCV prophylaxis among ATG-treated CMV-seropositive KT recipients. This performance is slightly improved by modifying the IFN-γ positivity threshold.

Clinical course and risk factors for mortality from COVID-19 in patients with haematological malignancies.

BACKGROUND: The impact of coronavirus disease 2019 (COVID-19) in haematological patients (HP) has not been comprehensively reported. METHODS: We analysed 39 patients with SARS-CoV-2 infection and haematological malignancies. Clinical characteristics and outcomes were compared to a matched control group of 53 non-cancer patients with COVID-19. Univariate and multivariate analyses were carried out to assess the risk factors associated with poor outcome. RESULTS: The most frequent haematological diseases were lymphoma (30%) and multiple myeloma (30%). Eighty-seven % HP developed moderate or severe disease. Patients with haematological malignancies had a significantly higher mortality rate compared to non-cancer patients (35.9% vs 13.2%; P = .003 (odds ratio 6.652). The worst outcome was observed in chronic lymphocytic leukaemia patients. Only age >70 years and C reactive protein >10 mg/dl at admission were associated with higher risk of death (odds ratio 34.86, P = .003 and 13.56,P = .03). Persistent viral sheddind was detected in 5 HP. Active chemotherapy, viral load at diagnosis and COVID-19 therapy were not predictors of outcome. CONCLUSION: Mortality of COVID-19 is significantly higher in patients with haematological malignancies compared to non-cancer patients. The impact of persistent viral shedding must be considered in order to re-start therapies and maintain infectious control measures.

Varied clinical presentation and outcome of SARS-CoV-2 infection in liver transplant recipients: Initial experience at a single center in Madrid, Spain.

BACKGROUND: Which are the consequences of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in liver transplant (LT) recipients? METHODS: We attempted to address this question by reviewing our single-center experience during the first 2 months of the pandemics at a high incidence area. RESULTS: Nineteen adult patients (5 females) were diagnosed by May 5, 2020. Median age was 58 (range 55-72), and median follow-up since transplantation was 83 (range 20-183) months. Cough (84.2%), fever (57.9%), and dyspnea (47.4%) were the most common symptoms. Thirteen patients (68.4%) had pneumonia in x-ray/CT scan. Hydroxychloroquine was administered in 11 patients, associated with lopinavir/ritonavir and interferon ß in 2 cases each. Immunomodulatory therapy with tocilizumab was used in 2 patients. Immunosuppression (IS) was halted in one patient and modified in only other two due to potential drug interactions. Five (26.3%) patients were managed as outpatient. Two patients (10.5%) died, 10 (52.6%) were discharged home, and 2 (10.5%) were still hospitalized after a median follow-up of 41 days from the onset of symptoms. Baseline IS regimen remained unchanged in all surviving recipients, with good liver function. CONCLUSIONS: Our preliminary experience shows a broad spectrum of disease severity in LT patients with COVID-19, with a favorable outcome in most of them without needing to modify baseline IS.

Experience with leflunomide as treatment and as secondary prophylaxis for cytomegalovirus infection in lung transplant recipients: A case series and review of the literature.

BACKGROUND: Data concerning the use of leflunomide-a drug approved for rheumatoid arthritis with in vitro anticytomegalovirus (CMV) activity-in lung transplant (LT) recipients are scarce. AIMS: To report the use of leflunomide in LT recipients diagnosed with CMV infection/disease. MATERIAL AND METHODS: We performed a single-center retrospective study including LT recipients who received leflunomide for CMV infection or as secondary prophylaxis after viremia clearance. We also conducted a full systematic PubMed search until June 30, 2017. RESULTS: We identified 5 LT recipients in our center plus 7 patients reported in the literature. All patients had previously received ganciclovir (GCV) and foscarnet (FOS), with drug-induced adverse effects described in 6 recipients (50%). Antiviral resistance mutations were observed in 8 patients (66.7%). Leflunomide was prescribed for CMV infection in 9 of 12 patients (75%) and as secondary prophylaxis in 3 patients (25%). Initial decrease of CMV viremia after starting leflunomide was observed in 7 of 9 recipients (77.7%), although this response was only transient in 2 patients. Long-term suppression of CMV viremia was reported in 7 of 12 patients (58.3%). In 3 recipients (25%), leflunomide was discontinued due to adverse effects. DISCUSSION: Our study has some limitations, such as the small number of patients included, its retrospective nature, and absence of leflunomide drug monitoring in serum. Notwithstanding, in our experience, leflunomide proved to be particularly effective as an anti-CMV secondary prophylaxis treatment and for clearing low-grade viremia. Moreover, leflunomide combined with a short course of GCV or intravitreal FOS also proved to be very effective in some patients. CONCLUSION: Leflunomide, alone or in combination, could be an effective treatment in selected LT recipients with GCV-resistant CMV infection and as secondary prophylaxis. Further studies are necessary.

Rapid screening of SARS-CoV-2 variants, a key tool for pandemic surveillance.

The utility of reverse transcription-polymerase chain reaction (RT-PCR) in analysis SARS-COV-2 variants was evaluated. RT-PCR tests were used to analyse the majority of new SARS-CoV-2 cases (n = 9315) in a tertiary hospital (Madrid, Spain) throughout 2021. Subsequently, whole genome sequencing (WGS) was conducted on 10.8% of these samples (n = 1002). Notably, the Delta and Omicron variants emerged rapidly. There were no discrepancies between RT-PCR and WGS results. Continuous surveillance of SARS-CoV-2 variants is essential, and RT-PCR is a highly useful method, specially during periods of high COVID-19 incidence. This feasible technique can be implemented in all SARS-CoV-2 laboratories. However, WGS remains the gold standard method for comprehensive detection of all existing SARS-CoV-2 variants.

Systematic influenza screening in cardiac intensive care units during the influenza season: A prospective study in Spain.

BACKGROUND: Little is known about the incidence of influenza among admissions to the cardiac intensive care unit (C-ICU), accuracy of clinical suspicion, and influenza vaccination uptake. We evaluated the incidence of influenza at C-ICU admission during the influenza season, potential underdiagnosis, and vaccination uptake. METHODS: Prospective study at five C-ICUs during the 2017-2020 influenza seasons. A nasopharyngeal swab was collected at admission from patients who consented (n = 788). Testing was with Xpert®XpressFlu/RSV. RESULTS: Influenza was detected in 43 patients (5.5%) (40 FluA; 3 FluB) and clinically suspected in 27 (62.8%). Compared to patients without influenza, patients with influenza more frequently had heart failure (37.2% vs 22.8%, P = 0.031), previous contact with relatives with influenza-like illnesses (23.3% vs 12.5%, P = 0.042), antimicrobial use (67.4% vs 23.2%, P <0.01), and need for mechanical ventilation (25.6% vs 14.5%, P = 0.048). Patients received oseltamivir promptly. We found no differences in mortality (11.6% vs 5.2%, P = 0.076). Patients with influenza more frequently had myocarditis (9.3% vs 0.9%, P <0.01) and pericarditis (7.0% vs 0.8%, P = 0.01). Overall, 43.0% of patients (339/788) were vaccinated (51.9% of those with a clear indication [303/584]). CONCLUSION: Influenza seems to be a frequently underdiagnosed underlying condition in admissions to the C-ICU. Influenza should be screened for at C-ICU admission during influenza epidemics.

The role of the T-cell mediated immune response to Cytomegalovirus infection in intrauterine transmission.

INTRODUCTION: Prognostic markers for fetal transmission of Cytomegalovirus (CMV) infection during pregnancy are poorly understood. Maternal CMV-specific T-cell responses may help prevent fetal transmission and thus, we set out to assess whether this may be the case in pregnant women who develop a primary CMV infection. METHODS: A multicenter prospective study was carried out at 8 hospitals in Spain, from January 2017 to April 2020. Blood samples were collected from pregnant women at the time the primary CMV infection was diagnosed to assess the T-cell response. Quantitative analysis of interferon producing specific CMV-CD8+/CD4+ cells was performed by intracellular cytokine flow cytometry. RESULTS: In this study, 135 pregnant women with a suspected CMV infection were evaluated, 60 of whom had a primary CMV infection and samples available. Of these, 24 mothers transmitted the infection to the fetus and 36 did not. No association was found between the presence of specific CD4 or CD8 responses against CMV at the time maternal infection was diagnosed and the risk of fetal transmission. There was no transmission among women with an undetectable CMV viral load in blood at diagnosis. CONCLUSIONS: In this cohort of pregnant women with a primary CMV infection, no association was found between the presence of a CMV T-cell response at the time of maternal infection and the risk of intrauterine transmission. A detectable CMV viral load in the maternal blood at diagnosis of the primary maternal infection may represent a relevant biomarker associated with fetal transmission.

Other viral infections in solid organ transplantation.

Viral infections are a major cause of morbidity and even mortality in solid organ transplant recipients. This article reviews key aspects of infections in solid organ transplant recipients from respiratory viruses, such as influenza, polyomavirus, erythrovirus B19 and measles.

Cellular and humoral immune responses and breakthrough infections after three SARS-CoV-2 mRNA vaccine doses.

Background: SARS-CoV-2 vaccination has proven the most effective measure to control the COVID-19 pandemic. Booster doses are being administered with limited knowledge on their need and effect on immunity. Objective: To determine the duration of specific T cells, antibodies and neutralization after 2-dose vaccination, to assess the effect of a third dose on adaptive immunity and to explore correlates of protection against breakthrough infection. Methods: 12-month longitudinal assessment of SARS-CoV-2-specific T cells, IgG and neutralizing antibodies triggered by 2 BNT162b2 doses followed by a third mRNA-1273 dose in a cohort of 77 healthcare workers: 17 with SARS-CoV-2 infection prior to vaccination (recovered) and 60 naïve. Results: Peak levels of cellular and humoral response were achieved 2 weeks after the second dose. Antibodies declined thereafter while T cells reached a plateau 3 months after vaccination. The decline in neutralization was specially marked in naïve individuals and it was this group who benefited most from the third dose, which resulted in a 20.9-fold increase in neutralization. Overall, recovered individuals maintained higher levels of T cells, antibodies and neutralization 1 to 6 months post-vaccination than naïve. Seventeen asymptomatic or mild SARS-CoV-2 breakthrough infections were reported during follow-up, only in naïve individuals. This viral exposure boosted adaptive immunity. High peak levels of T cells and neutralizing antibodies 15 days post-vaccination associated with protection from breakthrough infections. Conclusion: Booster vaccination in naïve individuals and the inclusion of viral antigens other than spike in future vaccine formulations could be useful strategies to prevent SARS-CoV-2 breakthrough infections.