Review of cytomegalovirus seroprevalence and demographic characteristics associated with infection

The mRNA-1647 vaccine: A promising step toward the prevention of cytomegalovirus infection (CMV)

Cytomegalovirus (CMV) is a leading cause of congenital infections and significant health complications in immunocompromised individuals. With no licensed CMV vaccine available, the development of the mRNA-1647 offers promising advancements in CMV prevention. We have reviewed results from Phase 1 and 2 clinical trials of the mRNA-1647 vaccine, demonstrating robust immune responses in both seronegative and seropositive participants. Vaccines exhibited significantly elevated neutralizing antibody titers against CMV, particularly in fibroblast and epithelial cells, with sustained responses lasting up to 18 months post-vaccination. The mRNA-1647 vaccine triggered strong T-cell and memory B-cell responses, suggesting its potential for long-term protection against CMV infection. The ongoing Phase 3 CMVictory trial evaluates the safety and immunogenicity of mRNA-1647 in women of childbearing age, with preliminary data showing promise in preventing congenital CMV transmission. This vaccine could significantly reduce CMV-related morbidity and mortality, particularly in newborns and immunocompromised individuals, addressing a critical unmet medical need.

Virus-specific antibody responses in severe acute respiratory syndrome coronavirus 2-infected and vaccinated individuals

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can have a serious course with many complications, especially in immunocompromised individuals. In such persons, other latent virus infections may contribute to disease pathology, in particular viruses which infect immune cells such as Epstein-Barr virus (EBV) and cytomegalovirus (CMV).

METHODS

In this study, serology-based assays were conducted to analyse antibody responses to SARS-CoV-2 spike protein (SP), EBV Epstein-Barr nuclear antigen (EBNA)-1 and CMV phosphoprotein (pp)52 in naturally SARS-CoV-2-infected individuals, non-infected healthy controls (HCs) and vaccinated healthy controls (VHCs) to identify an association between SARS-CoV-2 antibodies and EBV and CMV antibodies in order to determine whether latent EBV and CMV infected individuals are more prone to become infected with SARS-CoV-2. Moreover, SARS-CoV-2, EBV, and CMV antibody responses were characterized in serum from patients with relapsing-remitting multiple sclerosis (RRMS), a chronic inflammatory disease strongly associated with EBV infections, to determine whether the serologic virus antibody profile varies in immunocompromised RRMS individuals upon SARS-CoV-2 vaccinations compared to VHCs.

RESULTS

Significantly elevated SP IgG, IgM and IgA levels were identified in SARS-CoV-2-infected immunocompetent individuals when compared to non-infected HCs. However, no correlation was found to serum antibodies between SARS-CoV-2, EBV, and CMV in individuals infected with SARS-CoV-2 and in VHCs, suggesting that latent infections with neither EBV nor CMV associates to SARS-CoV-2 infection. Moreover, no significant difference in SP IgG, IgA and IgM levels was observed between vaccinated RRMS patients and VHCs, indicating that the immune system of immune deficient RRMS patients and VHCs respond identical to SARS-CoV-2 vaccinations.

CONCLUSION

Collectively, SARS-CoV-2 SP antibody levels reflect the vaccination and infection history and do not associate with EBV and CMV serostatus.

A human cytomegalovirus prefusion-like glycoprotein B subunit vaccine elicits humoral immunity similar to that of postfusion gB in mice

Human cytomegalovirus (HCMV) is the leading infectious cause of birth defects. Despite the global disease burden, there is no Food and Drug Administration (FDA)-approved HCMV vaccine. The most efficacious HCMV vaccine candidates to date have used glycoprotein B (gB), a class III viral fusion protein, in its postfusion form. While some viral fusion proteins have been shown to elicit stronger neutralizing responses in their prefusion conformation, HCMV prefusion-like and postfusion gB were recently shown to elicit antibodies with similar fibroblast neutralization titers in mice. We aimed to define and compare the specificity and functionality of plasma IgG elicited by distinct prefusion-like and postfusion gB constructs. Prefusion-like and postfusion gB elicited comparable IgG responses that predominantly mapped to the AD-5 antigenic domain known to elicit neutralizing antibodies. Interestingly, postfusion gB elicited significantly higher plasma IgG binding to cell-associated gB and antibody-dependent cellular phagocytosis than that of prefusion-like gB. The vaccines elicited comparable neutralization titers of heterologous HCMV strain AD169r in fibroblasts; however, neither elicited neutralizing titers against the vaccine-matched strain Towne in fibroblasts. Our data indicate that gB in this prefusion-like conformation elicits similar specificity and functional humoral immunity to that of postfusion gB, unlike certain class I viral fusion proteins that have been used as vaccine antigens. These findings deepen our understanding of the immune response elicited by class III fusion proteins and may inform further design and testing of conformationally dependent herpesvirus glycoprotein vaccine candidates.IMPORTANCEVaccines against human cytomegalovirus (HCMV) still remain elusive in spite of the high disease burden of the virus, especially in pre-term infants and immunocompromised individuals. While vaccine efforts have focused on vaccine-induced antibodies to neutralize the virus, studies have increasingly shown the importance of other antibody functions in protection against cytomegalovirus (CMV) transmission. In this study, we comprehensively evaluated immune responses elicited by the prefusion state of an important HCMV protein called glycoprotein B (gB) in mice. Our results indicate that prefusion gB elicits immune responses similar to that of postfusion gB in mice and reveals areas for further redesign and testing for prefusion vaccine antigens against CMV and other herpesviruses, which could help in furthering vaccine development against HCMV.

Cytomegalovirus reactivation in patients with large B-cell lymphoma treated with chimeric antigen receptor T-cell therapy

Chimeric antigen receptor (CAR) T-cell therapy has improved outcomes of relapsed and/or refractory large B-cell lymphoma (r/r LBCL). However, its off-tumor effects result in severe prolonged humoral immune deficiency. Cytomegalovirus (CMV) is a latent virus that can be life-threatening in immunosuppressed patients. In the setting of CAR T-cell therapy, Asian race is a risk factor for clinically significant CMV infection. However, the effect of CAR T-cell therapy on CMV reactivation in Japanese patients remains unclear. Previous reports used polymerase chain reaction (PCR), but we used the pp65 antigenemia assay to retrospectively investigate long-term effects in patients with r/r LBCL. The study included 46 patients. Nine (19.6%) developed CMV reactivation, with a median onset of 13 days. Six of these patients received preemptive therapy, and none developed CMV end-organ disease. Primary refractory disease, grade 2-4 cytokine release syndrome, and high-dose corticosteroids were risk factors for CMV reactivation. Long-term follow-up showed that CMV reactivation rarely occurred later than 28 days post-infusion. Our study using the pp65 antigenemia assay showed a similar incidence of CMV reactivation, onset, and risk factors to those in the previous reports using PCR.

Evidence for a Causal Association Between Human Cytomegalovirus Infection and Chronic Back Pain: A One-Sample Mendelian Randomization Study

Background

Chronic back pain (CBP) is a major cause of disability globally. While its etiology is multifactorial, specific contributing genetic and environmental factors remain to be discovered. Paraspinal muscle fat has been shown in human and preclinical studies to be related to CBP. One potential risk factor is infection by cytomegalovirus (CMV) because CMV is trophic for fat. CMV may reside in the paraspinal muscle adipose tissue. We set out to test the hypothesis that previous CMV infection is linked to CPB using a one-sample Mendelian randomization (MR).

Method

The sample comprised 5140 UK Biobank participants with information about CMV serology and CBP status. A one-sample MR based on independent genetic variants predicting CMV positivity was conducted in Northern European participants. To validate the association further, the MR study was repeated using a CMV polygenic risk score (PRS). As a negative control for confounding and spurious causal inference, we used Epstein-Barr virus (EBV) serology, because EBV is another common viral infection but is not trophic for adipose tissue.

Results

A genome-wide association study for CMV seropositivity revealed 86 independent SNPs having p-value < 2 × 10 - 4 that have been used to define genetically-predicted categories of CMV infection risk. The CMV predicted categories were found statistically significantly associated with CBP (OR = 1.150; 95% CI: 1.005-1.317, p-value = 0.043). Stronger significant results were obtained using the PRS for CMV seropositivity (OR = 1.290; 95% CI: 1.133-1.469, p-value = 12E-4). No such association was seen between EBV and CBP.

Conclusion

Our results provide evidence for a causal relationship between CMV infection and CBP. Further investigation is warranted to get insight into the mechanism by which CMV might contribute to the pathogenesis of CBP.

Human cytomegalovirus gH/gL/gO binding to PDGFRα provides a regulatory signal activating the fusion protein gB that can be blocked by neutralizing antibodies

Herpesviruses require membrane fusion for entry and spread, a process facilitated by the fusion glycoprotein B (gB) and the regulatory factor gH/gL. The human cytomegalovirus (HCMV) gH/gL can be modified by the accessory protein gO, or the set of proteins UL128, UL130, and UL131. While the binding of the gH/gL/gO and gH/gL/UL128-131 complexes to cellular receptors, including PDGFRα and NRP2, has been well-characterized structurally, the specific role of receptor engagements by the gH/gL/gO and gH/gL/UL128-131 in regulation of fusion has remained unclear. We describe a cell-cell fusion assay that can quantitatively measure fusion on a timescale of minutes and demonstrate that binding of gH/gL/gO to PDGFRα dramatically enhances gB-mediated cell-cell fusion. In contrast, gH/gL/pUL128-131-regulated fusion is significantly slower, and gH/gL alone cannot promote gB fusion activity within this timescale. The genetic diversity of gO influenced the observed cell-cell fusion rates, correlating with previously reported effects on HCMV infectivity. Mutations in gL that had no effect on the formation of gH/gL/gO or binding to PDGFRa dramatically reduced the cell-cell fusion rate, suggesting that gL plays a critical role in linking the gH/gL/gO-PDGFRa receptor binding to activation of gB. Several neutralizing human monoclonal antibodies were found to potently block gH/gL/gO-PDGFRa-regulated cell-cell fusion, suggesting this mechanism as a therapeutic target.

IMPORTANCE

Development of vaccines and therapeutics targeting the fusion apparatus of human cytomegalovirus (HCMV) has been limited by the lack of an in vitro cell-cell fusion assay that faithfully models the receptor-dependent fusion characteristic of HCMV entry. The cell-cell fusion assay described here demonstrated that the binding of gH/gL/gO to its receptor, PDGFRα, serves to regulate the activity of the fusion protein gB, and this is specifically vulnerable to inhibition by neutralizing antibodies. Moreover, the measurement of fusion kinetics allows for mutational studies of the fusion mechanism, assessing the influence of genetic diversity among the viral glycoproteins and studying the mechanism of neutralizing antibodies.

Multifaceted profiling of virus-specific CD8 T cells reveals distinct immune signatures against cytomegalovirus infection states during pregnancy

Anti-cytomegalovirus (CMV) serological testing, including the IgG avidity index (AI), is used to assess CMV infection phases during pregnancy. However, little is known about anti-CMV cellular immunity during pregnancy, particularly its relation to serological diagnosis. Herein, using MHC-dextramer single-cell RNA sequencing and flow cytometry, we characterized IE1 and pp65 CMV-antigen specific CD8 T cells from pregnant women with different anti-CMV serological patterns, including IgG+IgM+/AI-low, IgG+IgM+/AI-high, and IgG+IgM-. In IgG+IgM+/AI-low and IgG+IgM+/AI-high specimens, CMV-specific T cells consisted largely of effectors, with a minor but characteristic proportion of memory T cells, including HLA-DR-positive memory precursors and granzyme K-high memory cells reactive to IE1. Conversely, IgG+IgM- cases had a distinctive expansion of pp65-specific terminally differentiated T effector memory with a signature of convergent clonal selection. Our findings revealed that different CMV infection phases have characteristic patterns of CD8 cell phenotype and antigen recognition, potentially offering a new approach for assessing congenital infection risk.

Impacts of donor age and HLA mismatch on HCT outcomes differ according to the donor CMV serostatus in unrelated allo-HCT

ABSTRACT

In unrelated allogeneic hematopoietic cell transplantation (allo-HCT), older and/or HLA-mismatched donors are known risk factors for survival outcomes. In healthy individuals, cytomegalovirus (CMV) seropositivity is associated with impaired adaptive immune systems. We assessed whether the adverse effects of donor risk factors are influenced by the donor CMV serostatus. We analyzed 5836 patients with CMV seropositivity who received unrelated allo-HCT. We divided the entire cohort into 2 cohorts according to the donor CMV serostatus: CMV positive (DP) and negative (DN). We also stratified each cohort into 4 groups based on donor age (aged ≥40 or <40 years) and HLA parity (8/8 or 7/8): Young88 and Old88, and Young78 and Old78, respectively. In the CMV-DP cohort, the Old88 (hazard ratio [HR], 1.20; P = .012), Young78 (HR, 1.35; P < .001), and Old78 (HR, 1.60; P < .001) groups were associated with inferior overall survival (OS) than the Young88 group. In contrast, in the CMV-DN cohort, neither donor age nor HLA disparity was associated with inferior OS. The adverse impact of donor age was different between the cohorts (CMV-DP: HR, 1.19; P = .001; CMV-DN: HR, 1.04; P = .53; P for interaction, .070), as was the impact of HLA (CMV-DP: HR, 1.34; P < .001; CMV-DN: HR, 1.08; P = .23; P for interaction, .012). The impacts of donor age and HLA mismatch on OS might differ according to the donor CMV serostatus. In unrelated allo-HCT from a CMV-seronegative donor, an HLA-mismatched older donor may be able to be selected without affecting OS.

Presence of Epstein-Barr Virus in Periapical Pathoses: A Systematic Review and Meta-Analysis

BACKGROUND

Periapical lesions, often arising from polymicrobial infections, exhibit varied clinical manifestations. The role of herpes viruses, particularly Epstein-Barr virus (EBV), in the etiopathogenesis of these conditions remains underexplored despite evidence that suggests its involvement in inflammatory processes.

OBJECTIVE

This systematic review and meta-analysis aimed to evaluate the presence of EBV in periapical diseases and to assess its probable role in their etiopathogenesis.

MATERIAL AND METHODS

Literature searches were conducted across PubMed, Scopus, Web of Science, and Google Scholar until July 2024. Original research that examined the association of EBV in periapical diseases was included for review. The risk of bias for each study was assessed using the modified Newcastle-Ottawa scale and Review Manager 5.4 was used to generate the results.

RESULTS

A total of 31 studies were included for qualitative synthesis, with 15 contributing to quantitative analysis. Findings revealed higher EBV detection rates in periapical lesions, particularly in symptomatic cases and lesions with larger sizes. Meta-analysis using random effects models also affirmed that EBV-positive transcripts significantly enhanced the risk of periapical lesions and symptomatic cases.

CONCLUSION

This review highlights a significant association between EBV and periapical lesions, particularly in symptomatic cases and larger lesions. The findings warrant further investigation into the mechanisms by which EBV contributes to the pathogenesis of periapical diseases and the implications for clinical management, including potential antiviral therapies.

PROSPERO REGISTRATION NUMBER

CRD4202344796.

Prevalence of opportunistic infections in Syrian inflammatory bowel disease patients on biologic therapy: a multi-center retrospective cross-sectional study

BACKGROUND

Hepatitis B, hepatitis C, cytomegalovirus (CMV), and tuberculosis (TB) pose significant risks to patients with inflammatory bowel disease (IBD) receiving biological therapy. However, data on the prevalence of these infections in Syria are scarce.

METHODS

We conducted a retrospective chart review of IBD patients receiving biologic therapy at Damascus Hospital and Ibn Al-Nafees Hospital, two major public institutions in Syria, between January 2021 and November 2024. A minimum sample size of 130 was estimated; however, all available records were reviewed.

RESULTS

Among 185 IBD patients (104 from Damascus and 81 from Ibn Al-Nafees), 51.4% had ulcerative colitis and 47.6% had Crohn's disease. The smoking prevalence was 9.2%, which was higher in Crohn's disease (5.9%) than in ulcerative colitis (3.2%). TST performed in 61.1% of patients, with 4.3% positivity, and interferon-gamma release assay (IGRA) in 8.7% (1.1% positive). Hepatitis B surface antigen (HBsAg) and anti-HBc antibodies were found in 2.7% and 5.4% of the patients, respectively, while hepatitis C seroprevalence was low (0.5%). CMV seropositivity was high in Damascus (50.8%), with two cases (1.1%) of CMV colitis. Biologic therapies included infliximab (42.7%), ustekinumab (24.3%), golimumab (10.8%), and adalimumab (6.5%). Data gaps, particularly in viral serology and TB screening, are notable.

CONCLUSION

This study identifies deficiencies in TB/hepatitis B screening (notably anti-HBs Ab) and elevated CMV seroprevalence among Syrian IBD patients receiving biologics, extending to immunosuppressed cohorts (rheumatology, dermatology, oncology). Insufficient screening heightens occult infection/reactivation risks, necessitating standardized pretreatment protocols to reduce morbidity in high-risk populations.

CLINICAL TRIAL NUMBER

Not applicable.

Frequency of CMV testing during pregnancy-a retrospective study

PURPOSE

The cytomegalovirus (CMV) belongs to the family of human Herpesviridae and is distributed worldwide. It is the most common cause of viral congenital infections and can have serious consequences for the health of the fetus in the event of a vertical transmission. This study, taking place for the first time in Upper Palatinate, Bavaria, aims to evaluate the frequency of CMV testing among pregnant women in our region in Germany, which for some individuals can be an expensive individual health service.

METHODS

Retrospectively, 1000 pregnant patients aged 17-45 years who were treated in the University Clinic St. Hedwig, Regensburg, Germany, were included in the study. It was investigated whether a CMV test was carried out during pregnancy and which results were obtained.

RESULTS

597 patients (59.7%) had not received a CMV test during pregnancy. Among the 403 (40.3%) patients who had undergone CMV testing, seropositivity was detected in 143 (35.5%). 257 patients (63.8%) were seronegative, while 3 (0.74%) had a primary infection.

CONCLUSION

Although CMV is the most common pathogen of viral congenital infections and can severely impair the health of affected newborns, CMV diagnostics during pregnancy is still not an integral part of the maternity guidelines in Germany, but rather an individual healthcare service, meaning that the patients undergoing the test must bear the full cost. An antiviral treatment with valacyclovir has shown good preventive and therapeutic success, but unfortunately, there is currently no vaccination available to prevent vertical transmission, which is why early diagnosis and hygiene measures are the most important means of preventing seroconversion of the mother and possible infection of the fetus.

Saliva Samples as a Potential Tool for the Diagnosis and Monitoring of Cytomegalovirus Reactivation in Children Undergoing Transplantation

BACKGROUND

Regular monitoring of cytomegalovirus (CMV) reactivation in children who undergo transplantation is performed by molecular testing on blood samples. This highlights the need to explore noninvasive alternatives, such as saliva. The present study evaluated the usefulness of saliva samples for detecting and monitoring CMV reactivation in children undergoing transplantation at a referral center in Lima, Peru.

METHODS

A total of 85 paired samples of liquid saliva and whole blood and 91 paired samples of swab-collected saliva and whole blood from 16 children who underwent transplantation were analyzed by quantitative polymerase chain reaction (qPCR).

RESULTS

The positivity rates for whole blood, liquid, and swab-collected saliva were 12.59%, 15.29%, and 12.09%, respectively. No significant differences were observed in viral load among the samples, and there was no remarkable correlation or agreement between saliva and whole blood. However, 19 samples from 4 patients were positive in their saliva but negative in their respective whole blood pairs. One patient who was positive in both the saliva samples and negative in blood developed gastrointestinal CMV disease.

CONCLUSIONS

Saliva may serve as a promising diagnostic tool for detecting and monitoring CMV reactivation in pediatric transplant recipients. Further studies should explore the significance of the saliva viral load to guide pre-emptive therapy and predict disease development.

Epidemiology and Clinical Features of Epstein-Barr Virus and Cytomegalovirus Infections in Japanese Infants and Young Children

The recent clinical features of Epstein-Barr virus (EBV) and cytomegalovirus (CMV) infections in young children in developed countries remain unclear. This study investigated the clinical features of EBV and CMV infections and the latest seroepidemiology in Japan. Seroprevalence was analyzed 303 stored serum samples using commercial Enzyme Immunosorbent Assay kits, and viral infections were investigated in a cohort of febrile children under 5 years of age. After maternal antibody levels declined, the seroprevalences of EBV and CMV gradually increased by adolescence to 42.9% and 57.1%, respectively. Among 2,732 febrile children, serum EBV and CMV DNAs were detected in 1.76% and 1.24%, respectively. Of 25 primary EBV-infected patients, 15 (60.0%) had infectious mononucleosis (IM) with significantly higher IM frequency, WBC, atypical lymphocyte ratios, AST, ALT, LDH, and EBV DNA load compared to EBV-reactivated patients. No CMV DNA-positive patients had IM. Among primary EBV-infected patients, those with IM were older and had more atypical lymphocytes and higher EBV DNA load than those without IM. The age of primary EBV infection appears to have decreased compared to reports from Western countries in the 1990s. Even among children under 5 years of age, 60.0% of those with primary EBV infection developed IM.

Cytomegalovirus serostatus among people with HIV, characterizing the prevalence, risk factors, and association with immune recovery

INTRODUCTION

Cytomegalovirus (CMV) infection is common among people with HIV (PWH), and may be associated with negative outcomes. We aimed to identify the seroprevalence of CMV between 01 January 1998 and 01 June 2022 among PWH accessing care at the Southern Alberta Clinic (SAC) and the associated risk factors. We also aimed to assess the impact of CMV seropositivity on CD4+ T-cells and CD4+/CD8+ ratio recovery among PWH who maintain HIV viral suppression.

METHODS

Poisson regression models with robust variance estimated crude and adjusted prevalence ratios and 95% confidence intervals to identify risk factors for CMV seronegativity. Among PWH maintaining viral suppression, trends in the median CD4+ T-cell count and CD4+/CD8+ ratio were visualized, and continuous time-to-event Cox proportional hazard models estimated hazards ratios (aHR) for CD4+ cell count recovery to ≥500 cells/mm3 and CD4+/CD8+ ratio of >1 at 10 years by CMV serostatus.

RESULTS

Among 3249 PWH, 2954 (91%) were CMV seropositive. CMV seronegativity was associated with younger ages, male sex, non-Hispanic white race and an education of ≥12 years. While CMV seronegativity did not affect CD4+ T-cell recovery following HIV viral suppression (aHR 1.15 [0.89-1.48]), it was associated with a greater likelihood of CD4+/CD8+ ratio normalization (aHR 2.38 [1.85-3.07]) at 10 years of follow-up.

CONCLUSIONS

CMV is a common coinfection among PWH. We found that CMV positivity among PWH maintaining HIV viral suppression, while not associated with CD4+ T-cell recovery, was associated with a reduced CD4+/CD8+ ratio recovery. This suggests an association with chronic CMV infection-mediated immune activation and inflammation among PWH.

Systematic review and meta-analysis of cytomegalovirus-associated adverse outcomes and healthcare resource utilization in hospitalized patients with inflammatory bowel disease

PURPOSE

Serious complications and unplanned healthcare utilization are reported among inflammatory bowel disease (IBD) hospitalizations with associated cytomegalovirus (CMV). The present systematic review and meta-analysis aimed to examine the in-hospital outcomes of CMV-related hospitalization in IBD patients.

METHODS

Electronic databases were systematically searched in PubMed, Web of Science (ISI), Scopus, Embase, and Google Scholar until February 2024. The quality of the included studies was assessed using the Newcastle-Ottawa Scale. Cochran's Q test and I2 statistics were applied to evaluate potential heterogeneity across eligible studies. The random-effects model obtained pooled odds ratio (OR) estimates and associated 95% confidence intervals (CI).

RESULTS

Sixteen articles were included in the meta-analysis, encompassing 5120 IBD patients diagnosed with comorbid CMV infection. Our findings indicated that compared to IBD patients without CMV, those with both CMV and IBD had a longer hospital length of stay (LOS) (8.65 days longer; 95% CI: 6.96, 10.34; P < 0.01), a greater colectomy risk (OR = 2.26; 95% CI: 1.53, 3.34; P < 0.01), and higher in-hospital mortality (OR = 2.83; 95% CI: 1.92, 4.16; P < 0.01). However, the difference in hospital charges between the two groups was not statistically significant (P = 0.78). Sensitivity analysis using the leave-one-out approach revealed significant changes in hospital costs after excluding certain studies. Additionally, subgroup analyses showed significant differences based on IBD subtypes for surgery risk and LOS.

CONCLUSION

Our findings suggest that CMV infection is associated with poorer outcomes in hospitalized IBD patients, highlighting the importance of early detection and appropriate management of CMV infection in this population to improve clinical outcomes and reduce healthcare resource utilization.

Apparent cooperativity between human CMV virions introduces errors in conventional methods of calculating multiplicity of infection

Whether infection of cells by individual virions occurs randomly or if there is some form(s) of competition or cooperativity between individual virions remains largely unknown for most virus-cell associations. Here we studied cooperativity/competition for three different strains of human cytomegalovirus ( HCMV ) on two different cell types (fibroblasts and epithelial cells). By titrating viral inocula concentrations in small steps over several orders of magnitude, and by using flow cytometry to precisely measure frequency of infected cells, we found that for most virus-cell associations, the frequency of cell infection increases faster than linear with an increasing inoculum concentration, indicating cooperativity between individual infecting virions. Mathematical modeling suggests that this apparent cooperativity cannot be explained by heterogeneity in either the infectivity of the individual virions or the resistance of individual cells to infection, or by simple aggregation/clumping of viral particles. Stochastic simulations of two additional alternative models that allow for i) reduction in cell resistance to infection when exposed to multiple virions, or ii) compensation in infectivity of poorly infectious virions when coinfecting cells with more infectious virions, resulted in apparent viral cooperativity. Analysis of other published datasets suggests presence of apparent viral cooperativity for HIV and vaccinia virus, infecting CRFK or HeLa cells, respectively, but not for tobacco mosaic virus forming plaques on plant leaves. We thus 1) propose a methodology to rigorously evaluate apparent cooperativity of viruses infecting target cells, and 2) demonstrate that knowing the degree of virus cooperativity for any given virus-cell combination is important for an accurate quantification of multiplicity of infection ( MOI ).

Graphical abstract

Infections per cell (IU/cell) and specific infectivity (Genomes/IU) of human cytomegalovirus depend on the infecting dose.

The struggles of breastfeeding mothers of preterm infants: a qualitative study

BACKGROUND

Breast milk, with its rich bioactive components and numerous maternal and infant health benefits, is globally recommended as the ideal food for babies, especially premature infants. With the elevated incidence of premature births, suboptimal breastfeeding rates are detrimental, especially considering numerous efforts to promote breastfeeding. The reasons for breastfeeding cessation remain unclear. This study utilizes the social-ecological system theory to explore reasons for the cessation of breastfeeding among mothers of premature infants in China.

METHODS

An interpretive phenomenological research design was implemented in Wuhan. Through purposive sampling, 14 mothers of premature infants who had discontinued breastfeeding were recruited in Wuhan, China. Semi-structured interviews were conducted to collect data guided by an interview outline developed by the theoretical framework. Content analysis was applied to analyze the interview data.

RESULTS

The overarching theme of this study was: "On the journey of breastfeeding, who will hold up the sky for me?" This theme encapsulated the multifaceted challenges faced by mothers before discontinuing breastfeeding and their urgent need for comprehensive support. For these mothers, breastfeeding represented not only a physiological challenge but also a significant psychological and emotional burden. The analysis identified three primary categories: Microsystems-the challenges of breastfeeding and adaptation barriers; Mesosystems-dysfunctional support systems within families and hospitals; and Macrosystems-insufficient social support systems.

CONCLUSIONS

Mothers of premature infants experienced weakened breastfeeding support systems, highlighting the need for (1) Enhancing psychological support and targeted breastfeeding guidance for mothers of preterm infants; (2) Establishing an evidence-based, coordinated support system that integrates hospital and family networks; (3) Strengthening monitoring and enforcement mechanisms for birth policies, enhancing breastfeeding facilities in public spaces, and improving the capacity for breastfeeding education and promotion within communities.

Nonhuman primate model mirroring human congenital cytomegalovirus infection reveals a spectrum of vertical transmission outcomes

Congenital cytomegalovirus (cCMV) is the leading infectious cause of birth defects worldwide, yet immune determinants of protection to inform maternal vaccine design remain elusive due to the lack of a translational animal model. Here, we characterized the outcome of primary rhesus CMV (RhCMV) infection in pregnant, immunocompetent, CMV-naïve rhesus macaques. RhCMV DNA was detected in amniotic fluid and/or fetal tissues in six of 12 (50% placental transmission) dams following early second trimester gestation RhCMV inoculation. Widespread tissue dissemination dominated by one of two inoculated RhCMV strains was present in one fetus (8.3% cCMV disease). Placental transmission was associated with elevated fetal and maternal plasma TNF-alpha and reduced maternal brain-derived neurotrophic factor and IL-10 levels. CMV exposure during pregnancy had a broad impact on the placenta and fetus even in the absence of congenital infection, as evidenced by ubiquitous maternal-fetal interface infection, and reduced placental efficiency and small-for-gestation age fetuses compared to control pregnancies. This model recapitulates key aspects of human cCMV and provides new insights into the complexity of CMV vertical transmission.

CMV serostatus is associated with improved survival and delayed toxicity onset following anti-PD-1 checkpoint blockade

Cytomegalovirus (CMV) is a globally endemic latent herpes virus that profoundly impacts T cell immunity. We investigated the oncological consequences of CMV infection across 341 prospectively recruited patients receiving immune checkpoint blockade (ICB) for melanoma. CMV+ patients with metastatic melanoma (MM) have higher lymphocyte counts, reduced neutrophil to lymphocyte ratio and divergent CD8+ T cell gene expression. Combination anti-CTLA-4/anti-PD-1 ICB, but not single-agent anti-PD-1 ICB, induces cytotoxicity and CMV-associated gene expression in CD8+ T cells from CMV- patients. Correspondingly, overall survival was independent of CMV serostatus in combination anti-CTLA-4/anti-PD-1 ICB recipients (CMV+ hazard ratio for death: 1.02, P = 0.92), whereas CMV+ single-agent anti-PD-1 ICB recipients had improved overall survival (CMV+ hazard ratio for death: 0.37, P < 0.01), a finding also seen in CMV+ adjuvant single-agent anti-PD-1 ICB recipients (CMV+ hazard ratio for recurrence: 0.19, P = 0.03). We identify TBX21, encoding T-bet, as a transcriptional driver of CMV-associated CD8+ T cell gene expression, finding that TBX21 expression is predictive of overall survival (hazard ratio: 0.62, P = 0.026). CMV+ patients unexpectedly show reduced cumulative incidence of grade 3+ immune-related adverse events at 6 months (0.30 versus 0.52, P = 2.2 × 10-5), with lower incidence of colitis (P = 7.8 × 10-4) and pneumonitis (P = 0.028), an effect replicated in non-melanoma ICB recipients (n = 58, P = 0.044). Finally, we find reduced CMV seropositivity rates in patients with MM compared with UK Biobank controls (odds ratio: 0.52, P = 1.8 × 10-4), indicating CMV seropositivity may protect against MM. Specifically, patients with BRAF-mutated MM are less likely to be CMV+ (odds ratio = 2.2, P = 0.0054), while CMV- patients present 9 yr earlier with BRAF wild-type MM (P = 1.3 × 10-4). This work reveals an interaction between CMV infection, MM development according to BRAF status and response to ICB, while demonstrating CMV infection is protective against severe ICB immune-related adverse events, highlighting the potential importance of previous infection history and chronic immune activation in MM development and immunotherapy outcomes.

Developing a Vaccine Against Human Cytomegalovirus: Identifying and Targeting HCMV's Immunological Achilles' Heel

Human cytomegalovirus (HCMV) is a critical pathogen in immunocompromised populations, such as organ transplant recipients as well as congenitally infected neonates with immature immune systems. Despite decades of research and the growing financial burden associated with the management of HCMV, there is no licensed vaccine to date. In this review, we aim to outline the complexity of HCMV and the antigens it presents and the journey and challenges of developing an effective HCMV vaccine, as well as further highlight the recent analyses of the most successful vaccine candidate so far-gB/MF59.

Human leukocyte antigen variation is associated with cytomegalovirus serostatus in healthy individuals

Cytomegalovirus (CMV) is a common β-herpes virus worldwide with an estimated seroprevalence among the general population of 83%. Primary infection is usually benign; however, CMV can cause severe morbidity in newborns in whom it is acquired congenitally, as well as immunocompromised individuals. Understanding the role of immunogenetic variation in risk for CMV infection can provide insight into the immune control of this ubiquitous pathogen. Here, we evaluated the association of human leukocyte antigen (HLA) genetic variation with CMV seropositivity in more than 518,000 individuals from two independent cohorts. We found three HLA class II alleles (HLA-DRB1∗04:03 with risk; HLA-DRB1∗01:03 and HLA-DRB1∗07:01 with protection) to be significantly associated with CMV serostatus across both cohorts and in multiple population subgroups. Interestingly, HLA-DRB1∗04:03 and HLA-DRB1∗01:03, the alleles with the strongest observed effect, are relatively rare, while common homologous alleles show no association with CMV. We show that these differences are mediated by changes in charge and volume to two key pockets in the peptide-binding groove of the HLA molecule, providing a structural basis for the observed association. Our results provide population-scale evidence for the role of HLA in mediating infection with this ubiquitous human virus and a framework for understanding immunological conditions necessary for efficient viral control.

Healthcare resource use and clinical events associated with neutropenia among adult kidney transplant recipients receiving valganciclovir or ganciclovir prophylaxis: a matched case-control cohort study

BACKGROUND

Cytomegalovirus prophylaxis with valganciclovir and ganciclovir is associated with increased neutropenia risk in kidney transplant recipients. This study assessed the association between neutropenia and short-term healthcare resource utilization (HCRU) and clinical events for adults receiving valganciclovir and/or ganciclovir prophylaxis post-kidney transplantation in the United States.

METHODS

Adult kidney transplant recipients from 2012 to 2020 who received valganciclovir and/or ganciclovir prophylaxis were identified in the TriNetX database. Patients with a neutropenia event during the 1-year post-kidney transplant were identified as cases and those without were identified as controls. Cases and controls were matched 1:1 on patient characteristics in the 1-year period before the kidney transplant. HCRU and clinical event rates in the year following the first neutropenia event were compared between the cases and controls.

RESULTS

Of 3564 identified case-control pairs, the average age was 52 years and 59.57% were male. Cases had higher HCRU in the first year after neutropenia than controls, characterized by 1.40-, 1.28-, and 1.33-times higher rates of inpatient, outpatient, and emergency department visits (all p < 0.001). Cases also had higher incident rates for cytomegalovirus-related events, use of granulocyte colony stimulating factor, and opportunistic infections (all adjusted incident rate ratios >1 with p < 0.01), and greater risks of death, graft loss, and acute graft rejection (all adjusted hazard ratios >1 with p < 0.001).

CONCLUSION

Higher HCRU and clinical burden were observed within the first year following post-transplant neutropenia. New options for cytomegalovirus prophylaxis that are less likely to induce neutropenia are needed to improve patient outcomes.

Human Cytomegalovirus Infection Reduces an Endogenous Antiviral Fatty Acid by Promoting Host Metabolism

Some viruses, including human cytomegalovirus (HCMV), induce the synthesis of fatty acids and lipids to ensure that the lipid environment of infected cells supports virus replication. HCMV infection broadly reprograms metabolism to ensure central carbon metabolism provides the metabolites required for anabolic synthesis of nucleotides, proteins, and lipids while also meeting the energy demands placed on the infected cells. While HCMV infection increases the levels of most very long chain fatty acids (VLCFA), we found that the levels of erucic acid (EA), a C22:1 monounsaturated VLCFA, are reduced. Treating infected cells with EA disrupted a late step in virus replication, resulting in the release of virions with reduced infectivity. Moreover, we used lipidomics to determine that EA-treated cells had elevated levels of lipids containing a combination of a C22:1 tail and a VLC polyunsaturated fatty acid tail (VLC-PUFA). We demonstrate that fatty acid elongase 5 (ELOVL5) mediated production of VLC-PUFAs is stimulated by HCMV infection. ELOVL5 aided the increase in lipids with C22:1 plus VLC-PUFA tails following EA treatment and reduced the overall level of C22:1 in HCMV-infected cells. Moreover, we found that ELOVL5 mollified EA inhibition of HCMV replication, suggesting ELOVL5 plays a critical role in reducing the level of an endogenous FA with antiviral properties. Our study provides insight into how infection may increase the synthesis of an antiviral metabolite or FA and how the virus may evade their antiviral effect by promoting their metabolism.

Herpesvirus Infections of the Corneal Endothelium

Corneal endotheliitis is an inflammatory process, most commonly of viral etiology, that manifests clinically with features including corneal edema, keratic precipitates, and a mild anterior chamber reaction. Several studies have implicated human herpesviruses from the Herpesviridae family as primary causes of corneal endotheliitis, including cytomegalovirus (CMV), varicella zoster virus (VZV), and herpes simplex viruses 1 and 2 (HSV-1 and HSV-2). This review critically evaluates the present literature surrounding herpesvirus infections of the corneal endothelium.

Daxx and HIRA go viral - How chromatin remodeling complexes affect DNA virus infection

Daxx and HIRA are key proteins in the host response to DNA virus infections. Daxx is involved in apoptosis, transcription regulation, and stress responses. During DNA virus infections, Daxx helps modulate the immune response and viral progression. Viruses like adenoviruses and herpesviruses can exploit Daxx to evade immune detection, either by targeting it for degradation or inhibiting its function. Daxx also interacts with chromatin to regulate transcription, which viruses can manipulate to enhance their own gene expression and replication. HIRA is a histone chaperone and reported to be essential for chromatin assembly and gene regulation. It plays a critical role in maintaining chromatin structure and modulating gene accessibility. During DNA virus infection, HIRA influences chromatin remodeling, affecting both viral and host DNA accessibility, which impacts viral replication and gene expression. Additionally, the histone variant H3.3 is crucial for maintaining active chromatin states. It is incorporated into chromatin independently of DNA replication and is associated with active gene regions. During viral infections, H3.3 dynamics can be altered, affecting viral genome accessibility and replication efficiency. Overall, Daxx and HIRA are integral to orchestrating viral infection programs, maintaining latency and/or persistence, and influencing virus-induced transformation by modulating chromatin dynamics and host immune responses, making them significant targets for therapeutic strategies once fully understood. Here, we summarize various DNA viruses and their crosstalk with Daxx and HIRA.

Valacyclovir for the prevention of cytomegalovirus infection after kidney transplantation

BACKGROUND

Cytomegalovirus (CMV) infection is a frequent complication after kidney transplantation (KT) and has various effects on recipient and graft survival. Although guidelines recommend anti-viral prophylaxis with ganciclovir or valganciclovir, there is a demand for alternative regimen for CMV prevention. We investigated the effects of a 3-month valacyclovir-based prophylaxis on CMV infection and clinical outcomes in KT recipients using a nationwide cohort.

METHODS

Overall, 2,584 KT recipients from 20 transplant centers registered with the Korean Organ Transplantation Registry between May 2014 and December 2019 were analyzed in this study. The recipients were divided into valacyclovir prophylaxis and non-prophylaxis groups, a 1:3 propensity score matching was performed, and 1,036 recipients (291 and 745 in the prophylaxis and non-prophylaxis groups, respectively) were analyzed. The impact of valacyclovir-based prophylaxis on CMV after KT, other clinical outcomes, and the risk factors for CMV infection development were investigated.

RESULTS

The prophylaxis group showed a lower incidence of CMV infection and rejection compared to the non-prophylaxis group (3.64 vs. 10.25 events/100 person-years and 1.85 vs. 7.27 events/100 person-years, respectively). Valacyclovir prophylaxis, donor age, deceased donor, length of hospitalization after KT, anti-thymocyte globulin use, and CMV serological mismatch between the donor and recipient were independent risk factors for CMV infection after KT.

CONCLUSIONS

Valacyclovir prophylaxis after KT significantly reduced CMV infection and rejection. We suggest that valacyclovir could be considered as an alternative strategy for CMV prophylaxis after KT. However, our study has limitations, including its retrospective design, variability in valacyclovir dosing and CMV monitoring, and unassessed confounding factors. Further prospective studies with standardized protocols and larger cohorts are needed to validate our findings.

Evaluation and Management of Congenital Cytomegalovirus Infection

The purpose of this review is to serve as an update on congenital cytomegalovirus (CMV) evaluation and management for obstetrician-gynecologists and to provide a framework for counseling birthing people at risk for or diagnosed with a primary CMV infection or reactivation or reinfection during pregnancy. A DNA virus, CMV is the most common congenital viral infection and the most common cause of nongenetic childhood hearing loss in the United States. The risk of congenital CMV infection from transplacental viral transfer depends on the gestational age at the time of maternal infection and whether the infection is primary or nonprimary. Although the risk of congenital CMV infection is lower with infection at earlier gestational ages, clinical sequelae are more severe with maternal infections earlier in gestation. At present, routine screening for maternal CMV infection is not recommended by U.S. guidelines. When maternal primary infection is confirmed in early pregnancy, emerging data support consideration of maternal antiviral therapy to prevent congenital CMV infection. When congenital CMV infection is confirmed, typically after an abnormal prenatal ultrasound result, there are more limited data on the utility of maternal antiviral therapy. Universal newborn screening for congenital CMV infection is not mandatory in most U.S. states at present. Newborns diagnosed with congenital CMV infection undergo an extensive evaluation to determine whether neurologic symptoms are present, which guides postnatal evaluation and management. In this review, we discuss the diagnosis and management of maternal CMV infection, the risk and diagnosis of congenital CMV infection, prevention and potential treatment of congenital CMV infection in utero, and neonatal congenital CMV infection diagnosis and management.

Shared interactions of six neurotropic viruses with 38 human proteins: a computational and literature-based exploration of viral interactions and hijacking of human proteins in neuropsychiatric disorders

INTRODUCTION

Viral infections may disrupt the structural and functional integrity of the nervous system, leading to acute conditions such as encephalitis, and neuropsychiatric conditions as mood disorders, schizophrenia, and neurodegenerative diseases. Investigating viral interactions of human proteins may reveal mechanisms underlying these effects and offer insights for therapeutic interventions. This study explores molecular interactions of virus and human proteins that may be related to neuropsychiatric disorders.

METHODS

Herpes Simplex Virus-1 (HSV-1), Cytomegalovirus (CMV), Epstein-Barr Virus (EBV), Influenza A virus (IAV) (H1N1, H5N1), and Human Immunodeficiency Virus (HIV1&2) were selected as key viruses. Protein structures for each virus were accessed from the Protein Data Bank and analyzed using the HMI-Pred web server to detect interface mimicry between viral and human proteins. The PANTHER classification system was used to categorize viral-human protein interactions based on function and cellular localization.

RESULTS

Energetically favorable viral-human protein interactions were identified for HSV-1 (467), CMV (514), EBV (495), H1N1 (3331), H5N1 (3533), and HIV 1&2 (62425). Besides immune and apoptosis-related pathways, key neurodegenerative pathways, including those associated with Parkinson's and Huntington's diseases, were frequently interacted. A total of 38 human proteins, including calmodulin 2, Ras-related botulinum toxin substrate 1 (Rac1), PDGF-β, and vimentin, were found to interact with all six viruses.

CONCLUSION

The study indicates a substantial number of energetically favorable interactions between human proteins and selected viral proteins, underscoring the complexity and breadth of viral strategies to hijack host cellular mechanisms. Further in vivo and in vitro validation is required to understand the implications of these interactions.

Recent thymic emigrants are preferentially recruited into the memory pool during persistent infection

Cytomegalovirus (CMV) leads to a unique phenomenon known as 'memory inflation,' where antigen-specific memory CD8+ T cells continue to accumulate in the peripheral tissues during the latent stage of infection. However, it is still not clear how the inflating pool of memory CD8+ T cells is generated and maintained. In this study, we used murine cytomegalovirus (MCMV) as a model of persistent infection and fate-mapping mice to determine the dynamics of CD8+ T cell recruitment into the memory pool. We found that neonatal exposure to CMV leads to an expansion of newly made CD8+ T cells (recent thymic emigrants, RTEs), which are maintained in the long-lived memory compartment. In contrast, CD8+ T cells made during the latent phase of infection (mature CD8+ T cells) contribute little to the memory pool. We also observed notable phenotypic differences between RTEs and mature cells. Whereas RTEs present at the time of infection gave rise to more effector memory cells, the cells produced later in infection were biased towards becoming central memory cells. Importantly, the preferential recruitment of RTEs into the effector memory pool also occurs during adult exposure to CMV. Collectively, these data demonstrate that persistent infection expands the RTE population, and timing of infection dictates whether neonatal or adult RTEs are 'locked in' to the memory pool.

Postnatal cytomegalovirus infection and its effect on hearing and neurodevelopmental outcomes among infants aged 3-10 months: A cohort study in Eastern Uganda

BACKGROUND

Hearing impairment and neurodevelopmental disorders pose a significant global health burden in children. The link between postnatal cytomegalovirus (CMV) infection and these outcomes remains unclear. This study explored the association of postnatal CMV infection with hearing and neurodevelopmental outcomes in term infants aged 3 to 10 months.

METHODS

This was a cohort sub-study within the BabyGel cluster randomised trial in Eastern Uganda. From 1265 term infants screened for CMV, 219 were negative at birth but positive at 3 months, and were age-matched with 219 CMV-negative controls. CMV status was determined by PCR screening of saliva samples, with positive results confirmed using urine samples (Chai Open qPCR, Santa Clara, CA). From the established cohort, 424 infants were successfully followed up between 3 to 10 months of age. Clinical assessments included neurodevelopmental evaluation using the Malawi Developmental Assessment Tool, the Hammersmith Infant Neurological Examination, and hearing screening using Otoacoustic Emission testing (Otoport Lite, Otodynamics Limited). Statistical analyses were performed using descriptive statistics, chi-square tests and log binomial regression models with Stata 18.

RESULTS

Of the 424 infants included in the study, 206 were postnatal CMV-infected and 218 were uninfected. Neurodevelopmental assessments indicated no differences between postnatal CMV-infected infants and uninfected groups (ARR 0.88, 95% CI [0.67, 1.15], p = 0.346). Hearing screening revealed a 1.99-fold increased risk of a positive result for postnatal CMV-infected infants compared to uninfected infants (67/106 vs. 39/106, 95% CI [1.27, 3.12], p = 0.003).

CONCLUSION

Postnatal CMV infection was associated with more positive hearing screenings, though no significant differences in neurodevelopmental outcomes were observed in early infancy. Exploration into the feasibility of incorporating hearing and CMV screening into routine care will play a vital role in early identification and intervention, improving the management of both hearing and CMV-related conditions in resource-limited settings.

Prevalence of Epstein-Barr Virus, Cytomegalovirus, and Periodontopathic Bacteria in Patients With Periodontitis: A Case-Control Study

OBJECTIVES

Opportunistic viruses such as cytomegalovirus (CMV) and Epstein-Barr virus (EBV) have been detected in gingival crevicular fluid (GCF) and saliva of patients with periodontal disease. However, the relationship between herpesviruses and periodontitis remains obscure. The aim of this case-control study was the detection and association of CMV and EBV with periodontitis.

MATERIAL AND METHODS

Forty-eight adults were included in this study: 24 patients with periodontitis (CP) and 24 periodontally healthy individuals (HS). All patients underwent periodontal examination, including probing depth (PD), clinical attachment loss (CAL), plaque index (PI), and bleeding on probing (BOP). Subgingival biofilm samples were collected from all patients and real-time PCR was performed for viral and bacterial detection. The odds ratio (OR) was calculated, and the chi-squared test or Fisher's exact test was performed to analyze the significant differences.

RESULTS

EBV was detected only in one healthy patient meanwhile no CMV was found. No statistically significant differences were found between the periodontal clinical parameters of EBV-positive patients and the negative ones: PI (p = 0.090), PD (p = 0.857), CAL (p = 0.801), and BOP (p = 0.104). Except for Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), Tannerella forsythia (Tf), Prevotella intermedia (Pi), and Treponema denticola (Td) showed a statistically significant association (p < 0.001) with the clinical periodontal parameters. Aa presence was not statistically associated with periodontal sites (p < 0.296). Tf and Pg were the most frequently detected periodontopathic bacteria in the CP group (91.7% sites).

CONCLUSION

The present case-control study showed that the prevalence of EBV and CMV did not show significant differences between the groups evaluated in the Spanish population.

Evaluation and comparison of three high throughput assays (Alinity m CMV, Aptima CMV Quant and cobas CMV) for quantifying CMV DNA in plasma samples

BACKGROUND

Cytomegalovirus (CMV) can cause symptomatic CMV syndrome or tissue-invasive CMV disease in immunocompromised individuals, including solid-organ transplant and hematopoietic stem cell transplant recipients. In these populations, monitoring of CMV load is essential, assessing both risk of disease and response to antiviral therapy. High throughput commercial assays are currently available for CMV quantitation, but they are often evaluated independently, with few studies comparing these assays. This study evaluated CMV quantitative assays for use with the Roche cobas 6800, Abbott Alinity m and Hologic Panther platforms using stored patient plasma.

METHODS

Analytical evaluation was performed using the 1st WHO international standard for human CMV for Nucleic Acid Amplification Techniques (cobas and Alinity m) or the Hologic CMV QC Calibrator 6 (Aptima). Parallel testing of 136 clinical plasma samples was performed across the three platforms.

RESULTS

Linearity for each assay ranged from 98.6 % to 99.96 % and precision and limit of quantitation were as expected with little variation between platforms. 136 clinical plasma samples were evaluated with similar agreement observed between each assay. The greatest positive agreement was between the Aptima Quant and Alinity m assays (95.6 %, 95 % CI 89-98.6 %) and the lowest between the Aptima Quant and cobas assays (94.1 %, 87.4-97.5 %).

CONCLUSIONS

All assays were sensitive and accurate when quantifying CMV, and performance across all 3 assays was comparable for monitoring CMV viral loads in patient plasma.

CMV Reactivation Following Allogeneic Transplantation in Children From a High-Seroprevalence Population: A Single-Center Experience in Colombia

INTRODUCTION

Cytomegalovirus (CMV) infection is a frequent complication among hematopoietic stem cell transplant (HSCT) recipients. Data regarding CMV reactivation in children in underdeveloped countries is scarce. This is especially notable considering the increasing utilization of haploidentical-related HSCT with the post-transplant cyclophosphamide platform. This study aimed to describe the incidence, clinical characteristics, and evolution of children with CMV reactivation after HSCT and the possible impact of unmanipulated stem cells with PTCy for GvHD prophylaxis.

METHODS

Retrospective cohort study of children undergoing hematopoietic stem cell transplantation from January 2012 to June 2022. Baseline characteristics and the clinical course were described. Duration of treatment, initial viral load, and time to clearance of DNAemia by type of transplant were compared using the Kruskal-Wallis test. Survival analysis was performed with the Kaplan-Meier method and log-rank test. All statistical analysis was performed using SPSS software, version 20.0.

RESULTS

One hundred sixty-six children were included. Among them, 87% of recipients and 88% of donors were CMV positive. The cumulative incidence of cytomegalovirus DNAemia was 28% at 100 days post-transplantation. There were no differences between different donor types. Overall survival at 1 year was 60%, and non-relapse mortality was observed in 28%. CMV reactivation did not appear to negatively impact 1-year overall survival (OS).

CONCLUSIONS

Our study found no differences in CMV reactivation rates, treatment duration, viral clearance times, co-infections, or 1-year overall survival across different HSCT donor types. Studies are needed to establish more precise criteria for monitoring recipients, particularly in regions where unmanipulated stem cells with PTCy for GvHD prophylaxis are increasing.

Taming the transplant troll: Exploring racial and ethnic disparities in cytomegalovirus infection among kidney transplant patients

BACKGROUND

Cytomegalovirus (CMV) infection poses a significant risk to kidney transplant recipients. This study investigated CMV disease incidence, outcomes, and management challenges in racial and ethnic minority populations following kidney transplantation.

METHODS

This single-center, mixed-methods study included a retrospective cohort analysis of kidney transplant recipients (n = 58) and qualitative surveys of healthcare providers. Patients were categorized as minorities (n = 49) or non-Hispanic whites (n = 9). The primary outcome was CMV disease incidence. Secondary outcomes included graft failure, mortality, and identification of management barriers.

RESULTS

The cumulative incidence of CMV disease was higher in minorities than in non-Hispanic whites (12.3% vs. 0%, p = 0.58), although the difference was not statistically significant. All graft failures (8.6%, n = 5) occurred in the minority group. Although not statistically significant, all-cause mortality was higher in the minority group (24.5% vs. 11.1%, p = 0.54), with 46.2% of the deaths occurring within 90 days of CMV diagnosis. Qualitative analysis revealed challenges in diagnosis, treatment-related side effects, medication costs, and insurance barriers. The providers emphasized the importance of interdisciplinary collaboration and standardized protocols.

CONCLUSION

While limited by the small sample size, this study highlights potential disparities in the incidence and outcomes of CMV disease among minority kidney transplant recipients, suggesting that barriers in care and access may contribute to these differences. These hypothesis-generating findings underscore the need for larger multicenter studies to validate these patterns and to inform targeted strategies that may reduce inequities in post-transplant outcomes.

Characterization of Human Cytomegalovirus (HCMV) Long Non-Coding RNA1.2 During Lytic Replication

During lytic replication of human cytomegalovirus (HCMV), the most abundant viral transcripts are long non-coding RNAs (lncRNAs). Viral lncRNAs can have a variety of functions, some of which are necessary for viral production and the modulation of host processes during infection. HCMV produces four lncRNAs, Beta2.7 (RNA2.7), RNA4.9, RNA5.0 and RNA1.2. While there has been research on these viral lncRNAs, many of their functions remain uncharacterized. To determine the function of RNA1.2, we explored its requirement during lytic infection by generating viral mutants containing either a full or partial deletion of the RNA1.2 locus. Within permissive fibroblasts, the RNA1.2 deletion mutants showed no defects in viral DNA synthesis, transcript expression, protein production, or generation of viral progeny. Further investigation to identify potential cellular and viral protein binding partners of RNA1.2 was performed using liquid chromatography-mass spectrometry (LC-MS). A significant number of cellular proteins were identified and associated with RNA1.2. Specifically those associated with the innate immune response, mitochondrial processes, and cell cycle regulation. While RNA1.2 is dispensable for lytic replication, these findings suggest it may play a pivotal role in modulating the host response.

A nonhuman primate model mirrors human congenital cytomegalovirus infection and reveals a spectrum of vertical transmission outcomes

Congenital cytomegalovirus (cCMV) is the leading infectious cause of birth defects worldwide, yet immune determinants of protection to inform design of a maternal vaccine remain elusive. Here, we characterized the outcome of primary rhesus CMV (RhCMV) infection during pregnancy in an immune competent nonhuman primate (NHP) model. RhCMV DNA was detected in amniotic fluid and/or fetal tissues in six of 12 (50% placental transmission) CMV-naive rhesus macaque dams inoculated intravenously with RhCMV in early second trimester gestation. Widespread tissue dissemination dominated by one of two inoculated RhCMV strains was present in one fetus (8.3% cCMV disease). Placental RhCMV transmission was associated with elevated fetal and maternal plasma TNF-alpha and reduced maternal brain-derived neurotrophic factor and IL-10 levels. CMV exposure during pregnancy had a broad impact on the placenta and fetus even in the absence of congenital infection as evidenced by RhCMV infection at the maternal-fetal interface in all 12 dams, along with significantly reduced placental efficiency and fetal growth metrics compared to gestation-matched control pregnancies. This NHP model recapitulates key aspects of human cCMV and provides new insight into barriers and biomarkers of successful vertical transmission. One sentence summary: The nonhuman primate model mirrors the epidemiology of human congenital CMV (cCMV) after primary infection and reveals its transmission bottlenecks.

Human cytomegalovirus gH/gL/gO binding to PDGFRα provides a regulatory signal activating the fusion protein gB that can be blocked by neutralizing antibodies

Herpesviruses require membrane fusion for entry and spread, a process facilitated by the fusion glycoprotein B (gB) and the regulatory factor gH/gL. The human cytomegalovirus (HCMV) gH/gL can be modified by the accessory protein gO, or the set of proteins UL128, UL130 and UL131. While the binding of the gH/gL/gO and gH/gL/UL128-131 complexes to cellular receptors including PDFGRα and NRP2 has been well-characterized structurally, the specific role of receptor engagements by the gH/gL/gO and gH/gL/UL128-131 in regulation of fusion has remained unclear. We describe a cell-cell fusion assay that can quantitatively measure fusion on a timescale of minutes and demonstrate that binding of gH/gL/gO to PDGFRα dramatically enhances gB-mediated cell-cell fusion. In contrast, gH/gL/pUL128-131-regulated fusion is significantly slower and gH/gL alone cannot promote gB fusion activity within this timescale. The genetic diversity of gO influenced the observed cell-cell fusion rates, correlating with previously reported effects on HCMV infectivity. Mutations in gL that had no effect on formation of gH/gL/gO or binding to PDGFRα dramatically reduced the cell-cell fusion rate, suggesting that gL plays a critical role in linking the gH/gL/gO-PDGFRα receptor-binding to activation of gB. Several neutralizing human monoclonal antibodies were found to potently block gH/gL/gO-PDGFRα regulated cell-cell fusion, suggesting this mechanism as a therapeutic target.

EBV-specific T-cell immunity: relevance for multiple sclerosis

Genetic and environmental factors jointly determine the susceptibility to develop multiple sclerosis (MS). Improvements in the design of epidemiological studies have helped to identify consistent environmental risk associations such as the increased susceptibility for MS following Epstein-Barr virus (EBV) infection, while biological mechanisms that drive the association between EBV and MS remain incompletely understood. An increased and broadened repertoire of antibody and T-cell immune responses to EBV-encoded antigens, especially to the dominant CD4+ T-cell EBV nuclear antigen 1 (EBNA1), is consistently observed in patients with MS, indicating that protective EBV-specific immune responses are deregulated in MS and potentially contribute to disease development. Exploitation of B-cell trajectories by EBV infection might promote survival of autoreactive B-cell species and proinflammatory B:T-cell interactions. In this review article, we illustrate evidence for a causal role of EBV infection in MS, discuss how EBV-targeting adaptive immune responses potentially modulate disease susceptibility and progression, and provide future perspectives on how novel model systems could be utilized to better define the role of EBV and viral pathogens in MS. Insights gained from these studies might facilitate the development of prevention strategies and more effective treatments for MS.

[Viral retinitis]

Viruses belonging to the herpes family group, including HSV (herpes simplex virus) 1 and 2, VZV (varicella zoster virus) and CMV (cytomegalovirus) are the leading causes of necrotizing retinitis. These viral retinal necroses generally manifest in three forms, depending on the patient's immune status: acute retinal necrosis (ARN), progressive outer retinal necrosis (PORN) and CMV retinitis. Although specific, effective drug treatments are available today, early treatment initiation is essential to avoid sight-threatening complications.

An epigenetic human cytomegalovirus infection score predicts viremia risk in seropositive lung transplant recipients

Cytomegalovirus (CMV) infection and reactivation in solid organ transplant (SOT) recipients increases the risk of viremia, graft failure and death. Clinical studies of CMV serostatus indicate that donor positive recipient negative (D+/R-) patients have greater viremia risk than D-/R-. The majority of patients are R+ having intermediate serologic risk. To characterize the long-term impact of CMV infection and assess viremia risk, we sought to measure the effects of CMV on the recipient immune epigenome. Specifically, we profiled DNA methylation in 156 individuals before lung or kidney transplant. We found that the methylome of CMV positive SOT recipients is hyper-methylated at loci associated with neural development and Polycomb group (PcG) protein binding, and hypo-methylated at regions critical for the maturation of lymphocytes. In addition, we developed a machine learning-based model to predict the recipient CMV serostatus after correcting for cell type composition and ancestry. This CMV episcore measured at baseline in R+ individual stratifies viremia risk accurately in the lung transplant cohort, and along with serostatus the CMV episcore could be a potential biomarker for identifying R+ patients at high viremia risk.

Integrating clinical data and genetic susceptibility to elucidate the relationship between systemic lupus erythematosus and human cytomegalovirus infection

BACKGROUND

Viral infections are known to induce the occurrence and pathogenesis of systemic lupus erythematosus (SLE). Previous studies have indicated a possible relationship between SLE and human cytomegalovirus (HCMV) infection and have attributed HCMV to be associated with various autoantibodies; however, these studies were constrained by variations in sample size and potential selection bias. Therefore, in the present study, we aimed to elucidate the relationship between HCMV and autoantibodies in patients with SLE by integrating clinical data and genetic susceptibility.

METHODS

Using various statistical methods, we conducted a retrospective analysis of the spectrum of SLE autoantibodies and HCMV infections among patients hospitalized at our center over the past 10 years. Machine learning modeling was used to predict active HCMV infections based on the antinuclear (ANA) spectrum. Moreover, Mendelian randomization (MR) was used to investigate the causal relationship between SLE and HCMV infection.

RESULTS

In the HCMV group, the levels of ANA, anti-dsDNA, anti-histone antibody (AHA), and anti-nucleosome antibody (ANuA) were significantly increased (P < 0.001) and were linked to the presence of CMV-pp65-antigen-positive polymorphonuclear leukocytes (P < 0.001). A weak correlation was observed between the titers of anti-CMV IgM and ANA (P < 0.001). The ANA spectrum demonstrated a strong predictive performance for active HCMV infection based on principal component analysis (Adonis and ANOSIM P < 0.001) as well as support vector machine and extreme gradient boosting modeling. MR analyses of inverse-variance weighted, weighted mean, MR-Egger, and weighted mode revealed that patients with SLE were at a higher risk of developing HCMV infection (P < 0.05). However, HCMV infection did not have a causal effect on SLE (P > 0.05).

CONCLUSION

The ANA spectrum in patients with SLE can be used to predict HCMV infection status. Due to the inherent susceptibility of patients with SLE to HCMV infection, we propose for the first time that if a patient with SLE exhibits high serum titers of ANA, anti-dsDNA, ANuA, and AHA, caution should be exercised for HCMV infection, which can contribute to the clinical assessment of SLE and improve patient prognosis.

CMV Infection Risk Factors and Viral Dynamics After Valganciclovir Prophylaxis: 10 Years of Experience in Lung Transplant Recipients

(1) The prevention of cytomegalovirus (CMV) in lung transplant recipients (LTx) is based on the administration of VGC for a period of 6-12 months, but there is little information on the premature discontinuation of the drug. Our objective was to evaluate the reasons for early cessation of VGC and the dynamics of CMV replication after discontinuation. (2) We carried out a retrospective study of LTx on VGC prophylaxis according to guidelines, with an outpatient follow-up period of >90 days. The detection of any level of CMV-DNA in the plasma (Cobas, Roche Diagnostics®) during a period of 18 months after the discontinuation of VGC was considered positive. (3) We included 312 patients (64% male, mean age 53.50 ± 12.27; 71% D+R+, 15% D-R+, and 14% D+R-) in our study. The prescribed prophylaxis was completed by 179 patients (57.05%). The mean duration of prophylaxis was 7.17 ± 1.08 months. The recorded reasons for VGC discontinuation in 133 patients (43%) were myelotoxicity (n = 55), impaired renal function (n = 32), and gastrointestinal disturbances (n = 11). The reason for discontinuation was not recorded for 29 patients. CMV-DNA was detected in 79% (n = 246) of cases, and D+R+ and D+R- recipients showed a high risk of detection (p < 0.001). The median times to onset of CMV-DNA detection were 35 days in D+R-, 73 days in D+R+, and 96 days in D-R+ (p < 0.001). (4) Adverse effects of VGC are frequent in LTx. CMV-DNA detection is very common after the discontinuation of VGC and is related to the CMV donor and recipient serostatus.

Charting Peptide Shared Sequences Between 'Diabetes-Viruses' and Human Pancreatic Proteins, Their Structural and Autoimmune Implications

Diabetes mellitus (DM) is a metabolic syndrome characterized by hyperglycaemia, polydipsia, polyuria, and weight loss, among others. The pathophysiology for the disorders is complex and results in pancreatic abnormal function. Viruses have also been implicated in the metabolic syndrome. This study charted peptides to investigate and predict the autoimmune potential of shared sequences between 8 viral species proteins (which we termed 'diabetes-viruses') and the human pancreatic proteins. The structure and immunological relevance of shared sequences between viruses reported in DM onset and human pancreatic proteins were analysed. At nonapeptide mapping between human pancreatic protein and 'diabetic-viruses', reveal 1064 shared sequences distributed among 454 humans and 4288 viral protein sequences. The viral results showed herpesviruses, enterovirus (EV), human endogenous retrovirus, influenza A viruses, rotavirus, and rubivirus sequences are hosted by the human pancreatic protein. The most common shared nonapeptide was AAAAAAAAA, present in 30 human nonredundant sequences. Among the viral species, the shared sequence NSLEVLFQG occurred in 18 nonredundant EVs protein, while occurring merely in 1 human protein, whereas LGLDIEIAT occurred in 8 influenza A viruses overlapping to 1 human protein and KDELSEARE occurred in 2 rotaviruses. The prediction of the location of the shared sequences in the protein structures, showed most of the shared sequences are exposed and located either on the surface or cleft relative to the entire protein structure. Besides, the peptides in the viral protein shareome were predicted computationally for binding to MHC molecules. Here analyses showed that the entire 1064 shared sequences predicted 203 to be either HLA-A or B supertype-restricted epitopes. Fifty-one of the putative epitopes matched reported HLA ligands/T-cell epitopes majorly coming from EV B supertype representative allele restrictions. These data, shared sequences, and epitope charts provide important insight into the role of viruses on the onset of DM and its implications.

Seroprevalence of human herpes viruses in France, 2018-2022: a multilevel regression and poststratification approach

BACKGROUND

Information related to herpes simplex virus 1 and 2 (HSV-1 and 2), varicella-zoster virus (VZV), Epstein-Barr virus (EBV), and cytomegalovirus (CMV) seroprevalence in France is either lacking, incomplete, or outdated, despite their public health burden.

METHOD

We used routinely collected serological data between 2018 and 2022 to estimate HSV-1, HSV-2, VZV, EBV, and CMV seroprevalence in France. To account for demographic differences between our analytic samples and the French population and get estimates for sparsely sampled districts and age classes, we used a multilevel regression and poststratification approach combined with Bayesian model averaging via stacking weights.

RESULTS

The observed seroprevalence (number of positive tests/number of tests) were 64.6% (93,294/144,424), 16.9% (24,316/144,159), 93.0% (141,419/152,084), 83.4% (63,199/75, 781), and 49.0% (23,276/47,525), respectively, for HSV-1, HSV-2, VZV, EBV, and CMV. Between 2018 and 2022, France had a model-based average (equal-tailed interval at 95%) expected seroprevalence equal to 61.1% (60.7,61.5), 14.5% (14.2,14.81), 89.5% (89.3,89.8), 85.6% (85.2,86.0), and 50.5% (49.3,51.7), respectively, for HSV-1, HSV-2, VZV, EBV, and CMV infections. We found an almost certain lower expected seroprevalence in Metropolitan France than in overseas territories for all viruses but VZV, for which it was almost certainly greater. The expected seroprevalences were likely greater among females for all viruses.

LIMITATIONS

Our results relied on the assumption that individuals were sampled at random conditionally to variables used to build the poststratification table.

IMPLICATIONS

The analysis highlights spatial and demographic patterns in seroprevalence that should be considered for designing tailored public health policies.

Seroprevalence and Molecular Detection of Cytomegalovirus UL146 and US28 Gene Expression in Women With Recurrent Pregnancy Loss

Background Human cytomegalovirus (CMV) is a global herpesvirus that is highly prevalent worldwide and is able to establish lifelong latency after initial infection. The infection is highly frequent during pregnancy in human beings, which leads to preterm birth in some cases. Circulating strains of CMV carry a high number of variable or disrupted genes. Some of these like UL146, a highly diverse gene, and the US28 gene are involved in viral dissemination. This study aims to determine the seroprevalence of CMV and to investigate whether the highly variable UL146 and US28 genes, isolated from the blood of seropositive women, are associated with recurrent pregnancy loss. Material and methods This cross-sectional study was carried out in Erbil City, Iraq from October 2022 to July 2023. A total of 150 women at their reproductive age with a history of miscarriage who attended Maternity Teaching Hospital were enrolled. Anti-CMV IgG and IgM antibodies were assessed by enzyme-linked immunosorbent assay (ELISA). Highly variable UL146 and US28 genes of CMV from seropositive samples were amplified by conventional polymerase chain reaction (PCR), and the results were visualized on a UV-transilluminator. SPSS version 22 (IBM Corp., Armonk, NY, USA) was used for data entry and analysis. The p-value less than 0.05 was regarded as statistically significant. Results Anti-CMV IgG and IgM were seropositive in 103 (53.3%) and 13 (8.7%) women, respectively, and only 10 (6.7%) of them for both anti-CMV IgG and IgM. Significant associations of CMV and history of miscarriage, age, educational level, and gestational age of miscarriages were observed (p-value less than 0.05). On the other hand, no statistically significant association between CMV and socioeconomic level or residency was observed. The frequencies of genetic analysis of UL146 and US28 of the 103 seropositive tested samples of women with a history of miscarriage were 31 (30.1%) and nine (8.7%), respectively. A significant association between recurrent miscarriage and UL146 gene expression was observed. PCR targeting the UL146 demonstrated greater sensitivity for diagnosing CMV. Conclusion The seroprevalence of CMV is relatively high in Erbil, and the UL146 and US28 genes can act as factors in the initial level of CMV. Therefore, molecular detection of these genes can aid in determining the virulence of CMV strains.

Research progress on V delta 1+ T cells and their effect on pathogen infection

The ongoing high occurrence of harmful infectious diseases significantly threatens human health. Existing methods used to control such diseases primarily involve targeting the pathogens, usually neglecting the vital role of host factors in disease advancement. Gamma delta (γδ) T cells act as a bridge between innate and adaptive immunity, playing a crucial role in combating pathogen invasion. Among these γδT cell subsets, which are categorized based on T cell receptor delta variable expression patterns, V delta (δ) 1+ T cells possess unique recognition abilities and regulatory characteristics and actively engage in various immune responses. The differentiation, development, and immune reactivity of Vδ1+ T cells are closely associated with the initial and progressive stages of infectious diseases. This article provides an overview of the classification, distribution, differentiation, and development of Vδ1+ T cells and their mechanisms in combating pathogenic infections, offering new insights for disease diagnosis and treatment.

Advancements in LAMP-Based Diagnostics: Emerging Techniques and Applications in Viral Detection with a Focus on Herpesviruses in Transplant Patient Management

Loop-mediated isothermal amplification (LAMP) is a highly effective molecular diagnostic technique, particularly advantageous for point-of-care (POC) settings. In recent years, LAMP has expanded to include various adaptations such as DARQ-LAMP, QUASR, FLOS-LAMP, displacement probes and molecular beacons. These methods enable multiplex detection of multiple targets in a single reaction, enhancing cost-effectiveness and diagnostic efficiency. Consequently, LAMP has gained significant traction in diagnosing diverse viruses, notably during the COVID-19 pandemic. However, its application for detecting Herpesviridae remains relatively unexplored. This group of viruses is of particular interest due to their latency and potential reactivation, crucial for immunocompromised patients, including organ and hematopoietic stem cell transplant recipients. This review highlights recent advancements in LAMP for virus diagnosis and explores current research trends and future prospects, emphasizing the detection challenges posed by Herpesviridae.

Severe Cytomegalovirus Congenital Infection With Neurological Compromise a Case Series Study in Mexico: Severe CMV and Neurological Compromise

Four cases of serious congenital cytomegalovirus (CMV) infections are described in this report. All cases were diagnosed postnatally using cerebrospinal fluid (3/4) or blood PCR (1/4) and histochemical study of the placenta (4/4). All infants were born prematurely. Maternal factors identified as significant were younger age at pregnancy and those from low-income social strata. The major clinical findings among patients with congenital CMV infection were hydrocephalus and persistent thrombocytopenia. The children's clinical condition did not improve over the course of the disease, leading to complications associated with extreme prematurity. Two of the children died, one of whom had severe brain malformations and showed neurological compromise at follow-up, seizures, motor impairment, and severe cognitive delay. It is essential to perform antenatal screening for possible CMV infection among pregnant women, even in countries with high population seropositivity, such as Mexico, to establish prenatal interventions to reduce the risk of fetal damage.

Association Between Maternal Cytomegalovirus Seropositivity, Preterm Birth, and Preeclampsia in Two Cohorts From Quebec, Canada: A Mediation Analysis

PROBLEM

Preterm birth and preeclampsia significantly contribute to infant morbidity and mortality, posing critical public health concerns. Viral infections, particularly Cytomegalovirus (CMV), associated with chronic inflammation, may play a role in these adverse pregnancy outcomes. The contribution of CMV to preterm birth and preeclampsia requires further investigation.

METHOD OF STUDY

Data from 6048 pregnant women from two prospective Quebec cohorts, recruited between May 2005 and August 2012, were analyzed. First-trimester CMV serology was the exposure variable. Associations were assessed using multivariable logistic regression adjusted by inverse probability treatment weighting (IPTW) of propensity scores. Mediation analyses estimated the direct effect of maternal CMV serostatus on preterm birth, excluding mediation by preeclampsia.

RESULTS

Preterm birth and preeclampsia proportions were 5.1% (95% CI: 4.6-5.7) and 1.9% (95% CI: 1.6-2.3), respectively. Multivariable logistic regression adjusted by IPTW showed associations between CMV seropositivity and preterm birth (OR 1.20, 95% CI: 1.02-1.41) and CMV seropositivity and preeclampsia (OR 1.41, 95% CI: 1.08-1.84). Mediation analysis indicated that 97% of the total effect of CMV seropositivity on preterm birth is direct, with the remaining 3% mediated by preeclampsia.

CONCLUSIONS

CMV seropositivity appears to be a risk factor for both preterm birth and preeclampsia. The effect of maternal CMV seropositivity on preterm birth is primarily direct, not mediated by preeclampsia. Future studies should explore the impact of preventive measures against CMV infection on the incidence of preterm delivery and preeclampsia.