Congenital cytomegalovirus infection: Clinical presentation, epidemiology, diagnosis and prevention

Functional Fc receptors are crucial in antibody-mediated protection against cytomegalovirus

Human cytomegalovirus is a medically important pathogen. Previously, using murine CMV (MCMV), we provided evidence that both neutralizing and nonneutralizing antibodies can confer protection from viral infection in vivo. In this study, we report that serum derived from infected animals had a greater protective capacity in MCMV-infected RAG-/- mice than serum from animals immunized with purified virus. The protective activity of immune serum was strictly dependent on functional Fcγ receptors (FcγR). Deletion of individual FcγRs or combined deletion of FcγRI and FcγRIV had little impact on the protection afforded by serum. Adoptive transfer of CD115-positive cells from noninfected donors demonstrated that monocytes represent important cellular mediators of the protective activity provided by immune serum. Our studies suggest that Fc-FcγR interactions and monocytic cells are critical for antibody-mediated protection against MCMV infection in vivo. These findings may provide new avenues for the development of novel strategies for more effective CMV vaccines or antiviral immunotherapies.

An Elastin-like Polypeptide-fusion peptide targeting capsid-tegument interface as an antiviral against cytomegalovirus infection

The tegument protein pp150 of Human Cytomegalovirus (HCMV) is known to be essential for the final stages of virus maturation and mediates its functions by interacting with capsid proteins. Our laboratory has previously identified the critical regions in pp150 important for pp150-capsid interactions and designed peptides similar in sequence to these regions, with a goal to competitively inhibit capsid maturation. Treatment with a specific peptide (PepCR2 or P10) targeted to pp150 conserved region 2 led to a significant reduction in murine CMV (MCMV) growth in cell culture, paving the way for in vivo testing in a mouse model of CMV infection. However, the general pharmacokinetic parameters of peptides, including rapid degradation and limited tissue and cell membrane permeability, pose a challenge to their successful use in vivo. Therefore, we designed a biopolymer-stabilized elastin-like polypeptide (ELP) fusion construct (ELP-P10) to enhance the bioavailability of P10. Antiviral efficacy and cytotoxic effects of ELP-P10 were studied in cell culture, and pharmacokinetics, biodistribution, and antiviral efficacy were studied in a mouse model of CMV infection. ELP-P10 maintained significant antiviral activity in cell culture, and this conjugation significantly enhanced P10 bioavailability in mouse tissues. The fluorescently labeled ELP-P10 accumulated to higher levels in mouse liver and kidneys as compared to the unconjugated P10. Moreover, viral titers from vital organs of MCMV-infected mice indicated a significant reduction of virus load upon ELP-P10 treatment. Therefore, ELP-P10 has the potential to be developed into an effective antiviral against CMV infection.

Congenital infectious encephalopathies from the intrapartum period to postnatal life

Congenital infections are a common but often underrecognized cause of fetal brain abnormalities, as well as fetal-neonatal morbidity and mortality, that should be considered by all healthcare professionals providing neurological care to fetuses and newborns. Maternal infection with various pathogens (cytomegalovirus, Toxoplasmosis, Rubella virus, Parvovirus B19, lymphocytic choriomeningitis virus, syphilis, Zika virus, varicella zoster virus) during pregnancy can be transmitted to the developing fetus, which can cause multisystem dysfunction and destructive or malformative central nervous system lesions. These can be recognized on fetal and neonatal imaging, including ultrasound and MRI. Imaging and clinical features often overlap, but some distinguishing features can help identify specific pathogens and guide subsequent testing strategies. Some pathogens can be specifically treated, and others can be managed with targeted interventions or symptomatic therapy based on expected complications. Neurological and neurodevelopmental complications related to congenital infections vary widely and are likely driven by a combination of pathophysiologic factors, alone or in combination. These include direct invasion of the fetal central nervous system by pathogens, inflammation of the maternal-placental-fetal triad in response to infection, and long-term effects of immunogenic and epigenetic changes in the fetus in response to maternal-fetal infection. Congenital infections and their neurodevelopmental impacts should be seen as an issue of public health policy, given that infection and the associated complications disproportionately affect woman and children from low- and middle-income countries and those with lower socio-economic status in high-income countries. Congenital infections may be preventable and treatable, which can improve long-term neurodevelopmental outcomes in children.

Beyond schistosomiasis: unraveling co-infections and altered immunity

Schistosomiasis is a neglected tropical disease caused by the helminth Schistosoma spp. and has the second highest global impact of all parasites. Schistosoma are transmitted through contact with contaminated fresh water predominantly in Africa, Asia, the Middle East, and South America. Due to the widespread prevalence of Schistosoma, co-infection with other infectious agents is common but often poorly described. Herein, we review recent literature describing the impact of Schistosoma co-infection between species and Schistosoma co-infection with blood-borne protozoa, soil-transmitted helminths, various intestinal protozoa, Mycobacterium, Salmonella, various urinary tract infection-causing agents, and viral pathogens. In each case, disease severity and, of particular interest, the immune landscape, are altered as a consequence of co-infection. Understanding the impact of schistosomiasis co-infections will be important when considering treatment strategies and vaccine development moving forward.

Molecular diagnosis of Cytomegalovirus infection: clinical performance of the Aptima transcription-mediated amplification assay toward conventional qPCR chemistry on whole blood samples

Human Cytomegalovirus (HCMV) infection is life-threatening for immunocompromised patients. Quantitative molecular assays on whole blood or plasma are the gold standard for the diagnosis of invasive HCMV infection and for monitoring antiviral treatment in individuals at risk of HCMV disease. For these reasons, an accurate standardization toward the WHO 1st International Standard among different centers and diagnostic kits represents an effort for better clinical management of HCMV-positive patients. Herein, we evaluate, for the first time, the performance of a new transcription-mediated amplification (TMA) assay versus quantitative polymerase chain reaction (qPCR) chemistry, used as a routine method, on whole blood samples. A total of 755 clinical whole blood specimens were collected and tested simultaneously with TMA and qPCR assays. The data showed a qualitative agreement of 99.27% for positive quantified samples and 89.39% for those undetected between the two tested methods. Evaluation of viremia in positive samples highlighted a good correlation between TMA and qPCR chemistries in terms of International Units (ΔLog10 IU/mL: -0.29 ± 0.40). The TMA assay showed a significant correlation with qPCR in patients monitored for up to 3 months, thus allowing an accurate assessment of viremia in transplant patients. Therefore, TMA chemistry showed good agreement with qPCR testing, used as a current diagnostic routine. It also offers important advantages, such as FDA approval on plasma and In Vitro Diagnostic (IVD) on both plasma and whole blood, automated workflow with minimal hands-on time, and random access loading, thus enabling a rapid and reliable diagnostic in HCMV-infected patients.

IMPORTANCE

In this paper, we describe the clinical performance of a novel transcription-mediated amplification (TMA) assay for the detection and quantification of human Cytomegalovirus (HCMV) DNA from whole blood samples. This is a pivotal analysis in immunocompromised patients [transplanted, HIV-positive, and Hematopoietic Stem Cell (HSC) recipients], and molecular tests with high sensitivity and specificity are necessary to evaluate the HCMV viral load in these patients. To our knowledge, this is the first in-depth evaluation of TMA chemistry for HCMV diagnosis on whole blood samples. Moreover, also technical aspects of this assay make it suitable for clinical diagnostics.

Congenital cytomegalovirus infection in newborns suspected of congenital rubella syndrome in Iran: a cross-sectional study

BACKGROUND

Following rubella virus control, the most important cause of congenital infections is human cytomegalovirus (HCMV). Congenital CMV (cCMV) may happen both in primary and non-primary maternal infections. The present study aimed to screen cCMV in symptomatic newborns suspected of congenital rubella syndrome (CRS) in Iran.

METHODS

Out of 1629 collected infants' serum samples suspected of CRS but negative for rubella IgM, 524 samples were selected regarding cCMV complications. These samples were divided into two age groups: 1- one month and younger, 2- older than 1 month up to one year. Anti-HCMV IgM detection was performed on these serums. Then HCMV IgG avidity assay and HCMV DNA detection were carried out on all samples with positive and borderline results in IgM detection.

RESULTS

Herein, 3.67% of symptomatic infants aged one month and younger had positive and borderline HCMV IgM, 12.5% of which had a low avidity index (AI). HCMV IgM detection rate among symptomatic infants older than one month to one year was 14.5%. Identified genotypes in this study were gB-1(63.63%), gB2 (18.18%), and gB3 (18.18%), respectively.

CONCLUSIONS

This comprehensive study was performed on serum samples of symptomatic infants clinically suspected of cCMV from all over Iran. There was a good correlation between serology findings and PCR.

Pooling Saliva Sample as an Effective Strategy for the Systematic CMV Screening of Newborns-A Multicentric Prospective Study

BACKGROUND

Cytomegalovirus is the most common cause of congenital infections worldwide. Screening all newborns in the first 2 weeks of life is the only way to detect all cases of congenital infection, allowing the monitoring of children with asymptomatic infection at birth and early intervention.

AIM

In this multicenter study, we aimed to evaluate the feasibility of using a saliva pool strategy for mass screening in 7 Portuguese hospitals, and to estimate the current prevalence of this congenital infection in these hospitals.

METHODS

A total of 7033 newborns were screened between June 2020 and June 2022, and 704 pools of 10 saliva samples were analyzed by polymerase chain reaction (PCR).

RESULTS

Of the 704 pools analyzed, 685 were negative and 19 had positive PCR results for cytomegalovirus. After individual PCR testing, 26 newborns had positive saliva results, of which 15 were confirmed by urine testing. Thus, this study's prevalence of congenital infection was 0.21% (95% confidence interval: 0.12%-0.35%).

CONCLUSIONS

In this study, the pooling strategy proved to be effective for the systematic screening of newborns, although this low prevalence raises questions regarding the cost-effectiveness of implementing universal screening. However, this prevalence is probably the result of the control measures taken during the pandemic; therefore, the rates are expected to return to prepandemic values, but only a new study after the pandemic will be able to confirm this.

Antiviral Approach to Cytomegalovirus Infection: An Overview of Conventional and Novel Strategies

Human cytomegalovirus (HCMV) is a herpesvirus capable of establishing a lifelong persistence in the host through a chronic state of infection and remains an essential global concern due to its distinct life cycle, mutations, and latency. It represents a life-threatening pathogen for immunocompromised patients, such as solid organ transplanted patients, HIV-positive individuals, and hematopoietic stem cell recipients. Multiple antiviral approaches are currently available and administered in order to prevent or manage viral infections in the early stages. However, limitations due to side effects and the onset of antidrug resistance are a hurdle to their efficacy, especially for long-term therapies. Novel antiviral molecules, together with innovative approaches (e.g., genetic editing and RNA interference) are currently in study, with promising results performed in vitro and in vivo. Since HCMV is a virus able to establish latent infection, with a consequential risk of reactivation, infection management could benefit from preventive treatment for critical patients, such as immunocompromised individuals and seronegative pregnant women. This review will provide an overview of conventional antiviral clinical approaches and their mechanisms of action. Additionally, an overview of proposed and developing new molecules is provided, including nucleic-acid-based therapies and immune-mediated approaches.

Seroepidemiological Survey of Cytomegalovirus Infection among Pregnant Women in Sudan

Human Cytomegalovirus (HCMV) is a leading healthcare problem associated with stillbirth and congenital abnormalities. Determining the seroprevalence and the possible risk factors related to HCMV infections may be a cornerstone in preventing its complications. This cross-sectional study was conducted in Kassala and River Nile States to determine the seroprevalence and risk factors associated with HCMV infection in pregnant women. One hundred eighty-four (n = 184) blood specimens were collected from pregnant women from February 2018 to January 2020. Enzyme-linked immunosorbent assay (ELISA) was used to detect HCMV-specific IgG and IgM antibodies. Socio-demographical characteristics of the women were collected using structured questionnaires. The results showed that HCMV IgG was detected in 170 (92.4%) of the blood specimens, and IgM was detected in 29/93 (31.2%). There was a significant relationship between the history of miscarriage and the presence of IgG and IgM with a p-value = 0.001 and between HCMV IgM and gestational stage (p-value = 0.028). The study found a strikingly high seroprevalence of HCMV infections among pregnant women in the investigated States. This high percentage of illiterate housewives living in rural areas makes it possible to reduce the incidence of HCMV infection in pregnant women by improving their knowledge, attitude, and practice regarding the route of viral transmission, which may reflect in lowering the rate of congenital diseases in their infants.

Lessons from Acquired Natural Immunity and Clinical Trials to Inform Next-Generation Human Cytomegalovirus Vaccine Development

Human cytomegalovirus (HCMV) infection, the most common cause of congenital disease globally, affecting an estimated 1 million newborns annually, can result in lifelong sequelae in infants, such as sensorineural hearing loss and brain damage. HCMV infection also leads to a significant disease burden in immunocompromised individuals. Hence, an effective HCMV vaccine is urgently needed to prevent infection and HCMV-associated diseases. Unfortunately, despite more than five decades of vaccine development, no successful HCMV vaccine is available. This review summarizes what we have learned from acquired natural immunity, including innate and adaptive immunity; the successes and failures of HCMV vaccine human clinical trials; the progress in related animal models; and the analysis of protective immune responses during natural infection and vaccination settings. Finally, we propose novel vaccine strategies that will harness the knowledge of protective immunity and employ new technology and vaccine concepts to inform next-generation HCMV vaccine development.

Non-primary CMV infection not always innocent. A case-report and literature review

OBJECTIVES

Cytomegalovirus (CMV) is the most common infectious cause of congenital malformations. CMV infections are frequently symptomatic in case of a primary infection during pregnancy. Generally, maternal immunity protects the newborn against a symptomatic course of the CMV infection.

METHODS

We present clinical information and medical images of a neonate with non-primary congenital CMV infection.

RESULTS

We report the case of a severe congenital infection in a newborn clinically presenting with diffuse petechia, facial dysmorphisms, respiratory distress, hepatomegaly and hypotonia. The girl was born to a mother with CMV immunity. Blood results demonstrated thrombocytopenia and elevated transaminases. Brain MRI revealed ventricular dilatation and germinolytic cysts, compatible with CMV infection. Auditory brain stem response testing was abnormal. CMV culture of saliva was positive. This led to the diagnosis of a severe congenital CMV infection due to a non-primary maternal infection. Antiviral treatment with valganciclovir was initiated immediately and continued for 6 months.

CONCLUSION

Our case illustrates that, even when the mother was demonstrated CMV immune, congenital CMV infection is still an important differential diagnostic consideration in neonates presenting with congenital cerebral abnormalities, thrombocytopenia and/or hearing loss.

ABBREVIATIONS

ABR: auditory brainstem responses; CMV: Cytomegalovirus; CPAP: Continuous Positive Airway Pressure; CRP: C-Reactive Protein; dBnHL: Decibel Above Normal Adult Hearing Level; IV: intravenously; MRI: Magnetic Resonance Imaging; SGA: Small for Gestational Age; SNHL: Sensorineural Hearing Loss.

OUP accepted manuscript

Hepatitis B virus (HBV) remains a global public health problem despite the availability of effective vaccine and antiviral therapy. Cytomegalovirus (CMV), another hepatotropic virus, is also very prevalent in the general population worldwide. Both HBV and CMV can persist in the host and have potential to reactivate especially with weakened host cellular immunity. Superimposed CMV infection can lead to severe HBV reactivation. The pathogenesis of the co-infection of HBV and CMV remains poorly understood. Studies reported conflicting results regarding the inhibitory effect of CMV on HBV replication. There is an unmet need on the management of co-infection of HBV and CMV; research initiatives dedicated to understanding their interactions are urgently needed.

Comparison of detection strategies for screening and confirming congenital cytomegalovirus infection in newborns in a highly seroprevalent population: a mother-child cohort study

Background

Universal screening of congenital cytomegalovirus (cCMV) infection is important for monitoring and intervention during critical stages of speech and language development. This study aimed to explore the optimal detection strategy for cCMV infection screening.

Methods

Serum samples from pregnant women and saliva and urine samples from their newborns were collected for the anti-CMV IgG and CMV DNA PCR tests, respectively. The sensitivity, specificity, and predictive values as well as the likelihood ratios of 12 potential screening strategies for cCMV infection, based on tests for saliva, urine, and their combination, were evaluated.

Findings

A total of 6729 pregnant women were enrolled, and the seroprevalence was 98.1%. Among 6350 newborns that were followed up, 49 were defined as having cCMV infection. In the screening test, the CMV DNA positivity rate remained similar from day 0 to day 5, increased slowly from day 6 to day 13, and became high in newborns beyond 13 days of birth. In the confirmatory testing, the positive rates increased significantly beyond day 21. For the 49 newborns with cCMV infection, the proportion of agreement between saliva and urine testing was poor. Upon evaluating alternative screening strategies, using saliva and urine screening with saliva and urine confirmation as the reference strategy, saliva screening with saliva and urine confirmation showed good diagnostic accuracy and feasibility, with sensitivity, specificity, positive predictive and negative predictive values of 85.7%, 100.0%, 100.0% and 99.9%, respectively.

Interpretation

In populations with high seroprevalence, saliva screening with saliva and urine confirmation might be an alternative strategy for screening cCMV infections. The suggested timeframes for screening and confirmation are within 13 (ideally 5) and 21 (ideally 13) days of birth, respectively.

Funding

National Natural Science Foundation of China, National Science and Technology Major Project of China and Merck & Co., Inc., Kenilworth, New Jersey, U.S.A.

Epidemiological changes in cytomegalovirus end-organ diseases in a developed country: A nationwide, general-population-based study

BACKGROUND

Cytomegalovirus (CMV) can cause tissue-invasive diseases in various organs after primary infection or through reactivation of latent-to-lytic switch over a lifetime. The number of individuals who are at risk of CMV diseases, such as elderly or immunocompromised patients, is constantly increasing; however, recent epidemiological changes associated with CMV disease have not been fully evaluated.

METHODS

We used claims data of about 50 million individuals between 2010 and 2015 from the Korean Health Insurance Review and Assessment Service nationwide database. The code for CMV end-organ diseases in the 'Relieved Co-payment Policy' program matches the ICD-10 code of B25, except for congenital CMV infection and mononucleosis. A 628 cases of CMV and 3140 controls (without CMV disease), matched for age and sex, were selected from this dataset in order to evaluate the effect of adult CMV diseases on all-cause death.

RESULTS

The overall unadjusted incidence rate (IR) of CMV end-organ diseases was 0.52/100,000 individuals. The standardized IR, adjusted for age and sex, have continuously increased from 0.32/100,000 in 2010 to 0.75/100,000 in 2015. The overall unadjusted IR in adult population was highest in 70-79 years for six years (0.96/100,000). In the model adjusted for age, sex, immunocompromised status including solid-organ or hematopoietic stem cell transplant recipients, hematologic malignancies, and human immunodeficiency virus diseases, the hazard ratio of case group was 5.2 (95% confidence interval, 3.6-7.4) for all-cause mortality.

CONCLUSION

Nationwide data indicates that CMV end-organ disease has steadily increased in the past six years and is associated with higher mortality.

Prevention of Congenital Cytomegalovirus Infection with Vaccines: State of the Art

Cytomegalovirus (CMV) is the most common cause of congenital infection and non-genetic sensorineural hearing loss in childhood. Up to 2% of neonates, with the highest percentages found in developing countries, are congenitally infected with CMV. At birth, most of these infants are asymptomatic. However, approximately 10% have signs and symptoms of the disease, and 40–60% of symptomatic neonates will later develop permanent neurologic sequelae. To reduce congenital CMV (cCMV) infection, a vaccine able to prevent primary infection is essential. In this narrative review, actual ongoing research about the development of a CMV vaccine is discussed. The progressive increase in knowledge on the ways in which the host’s immune system and CMV relate has made it possible to clarify that the development of a vaccine that is certainly capable of reducing the risk of cCMV infection, and preventing both primary and nonprimary infections is extremely difficult. Many of the ways in which the virus evades the immune system and causes cCMV infection are not yet fully understood, especially in cases of nonprimary infection. Moreover, the schedule that should be recommended and that subjects must be vaccinated to obtain the greatest effect have not been precisely defined. Further studies are needed before the problem of cCMV infection and its related challenges can be totally solved.

IgA binds to the AD-2 epitope of glycoprotein B and neutralizes human cytomegalovirus

Human cytomegalovirus (HCMV) is a ubiquitous pathogen that is potentially pathogenic in immunosuppressed individuals and pregnant females during primary infection. The HCMV envelope glycoprotein B (gB) facilitates viral entry into all cell types and induces a potent immune response. AD-2 epitope is a highly conserved linear neutralizing epitope of gB and a critical target for antibodies; however, only 50% of sero-positive individuals make IgG antibodies to this site and IgA responses have not been fully investigated. This study aimed to compare IgG and IgA responses against gB and the AD-2 epitope in naturally exposed individuals and those receiving a recombinant gB/MF59 adjuvant vaccine. Thus, vaccination of sero-positive individuals improved pre-existing gB-specific IgA and IgG levels and induced de novo gB-specific IgA and IgG responses in sero-negative recipients. Pre-existing AD-2 IgG and IgA responses were boosted with vaccination, but de novo AD-2 responses were not detected. Naturally exposed individuals had dominant IgG responses towards gB and AD-2 compared with weaker and variable IgA responses, although a significant IgA binding response to AD-2 was observed within human breastmilk samples. All antibodies binding AD-2 contained kappa light chains, whereas balanced kappa/lambda light chain usage was found for those binding to gB. V region-matched AD-2-specific recombinant IgG and IgA bound both to gB and to AD-2 and neutralized HCMV infection in vitro. Overall, these results indicate that although human IgG responses dominate, IgA class antibodies against AD-2 are a significant component of human milk, which may function to protect neonates from HCMV.

Saliva pools for screening of human cytomegalovirus using real-time PCR

Human cytomegalovirus (HCMV) is the leading congenital infection agent in the world. The importance of screening this infection has been debated, as 10-15% of the asymptomatic newborns with HCMV at birth will present late sequelae. The aim of this study was to test the feasibility of using saliva pools from newborns in a screening program for congenital HCMV infection, in two Portuguese hospitals. The screening was based on the use of pools of 10 saliva samples for detection of viral DNA by real-time PCR. Whenever there was a positive pool, the samples were tested individually, and for each positive sample the result was confirmed with a urine sample collected in the first 2 weeks of life. The study involved 1492 newborns. One hundred and fifty pools were screened, with 14 positive results in saliva, but only 10 were confirmed in urine samples, giving a prevalence of congenital HCMV infection in both hospitals of 0.67% (CI95% 0.36 to 1.23%).Conclusion: The overall prevalence of congenital HCMV infection in both hospitals was 0.67%. The use of saliva pools proved to be effective for the screening of this congenital infection, allowing timely screening and confirmation in a large population, with associated cost reduction. What is Known: • Newborn screening for HCMV is desirable. • Saliva is a good and practical sample. What is New: • The feasibility of using saliva pools for a large-scale screening. • The cost reduction of this strategy.

Diagnostic significance of cytomegalovirus DNA quantitation in gastrointestinal biopsies: comparison with histopathological data and blood cytomegalovirus DNA

OBJECTIVES

This study aims to improve the diagnosis of gastrointestinal (GI) cytomegalovirus (CMV) disease. It presents the results of a novel study in which CMV blood viral load (BVL), tissue viral load (TVL) determined by PCR and hematoxylin-eosin (HE)/immunohistochemistry (IHC) results of GI biopsies are examined comparatively.

METHODS

CMV DNA was investigated by quantitative real-time PCR in blood and GI biopsy specimens of 76 patients suspected of CMV disease. Biopsies were also performed HE/IHC stainings in the pathology laboratory.

RESULTS

This study included 76 patients whose median age was 34.5 years and 58% (44) were male. Tissue CMV PCR positivity was detected in the highest colon (40/53;75.5%) samples. HE, IHC, blood and tissue CMV PCR positivity rates of all samples were 15.8, 25, 50 and 71.1%, respectively. When IHC was used as the gold standard test for ROC analysis, the optimal cutoff values for the maximum sensitivity and specificity for BVL and TVL were 1.91 log10 copies/ml and 3.82 log10 copies/mg, respectively. Sensitivity and specificity for the cutoff value of tissue CMV DNA were 78.9 and 74.3%, respectively (P < 0.001).

CONCLUSION

In this study, CMV DNA was detected in 71.1% of the tissue samples of the cases by PCR. Since the sensitivity of the histopathological examinations accepted as the gold standard is low, simultaneous with the histopathological examinations, determination of BVL, TVL and the identification of optimal cutoff values have been shown to support the diagnosis of GI CMV disease.

Hygiene promotion might be better than serological screening to deal with Cytomegalovirus infection during pregnancy: a methodological appraisal and decision analysis

BACKGROUND

Cytomegalovirus infection is the most frequent viral congenital infection, with possible consequences such as deafness, or psychomotor retardation. In 2016, the French High Council of Public Health was mandated to update recommendations regarding prevention of cytomegalovirus infection in pregnant women. We summarize a critical appraisal of knowledge and deterministic decision analysis comparing the current no-screening situation to serological screening during pregnancy, and to hygiene promotion.

METHODS

Screening was defined as systematic serological testing, during the first trimester, with repeated tests as needed, to all pregnant women. Outcomes were: 1) severe sequela: intellectual deficiency with IQ ≤ 50 or hearing impairment < 70 dB or sight impairment (≤ 3/10 at best eye); 2) moderate sequela: any level of intellectual, hearing or sight deficiency; and 3) death or termination of pregnancy. We simulated the one-year course of cytomegalovirus infection in a cohort of 800,000 pregnant women. We developed a deterministic decision model, using best and min-max estimates, extracted from systematic reviews or original studies.

RESULTS

Relevant data were scarce or imprecise. We estimated that 4352 maternal primary infections would result in 1741 foetal infections, and an unknown number of maternal reinfections would result in 1699 foetal infections. There would be 788 cytomegalovirus-related consequences, including 316 foetal deaths or terminations of pregnancy, and 424 moderate and 48 severe sequelae. Screening would result in a 1.66-fold increase of poor outcomes, mostly related to a 2.93-fold increase in deaths and terminations of pregnancy, not compensated by the decrease in severe symptomatic newborns. The promotion of hygiene would result in a 0.75-fold decrease of poor outcomes, related to both a decrease in severe sequelae among symptomatic newborns (RR = 0.75; min-max: 1.00-0.68), and in deaths and terminations of pregnancy (RR = 0.75; min-max: 0.97-0.68).

CONCLUSIONS

Prevention of cytomegalovirus infection during pregnancy should promote hygiene; serological screening should not be recommended.

A Cross-Sectional Study of Caregiver Perceptions of Congenital Cytomegalovirus Infection: Knowledge and Attitudes about Screening

OBJECTIVES

To understand caregiver knowledge of and attitudes toward congenital cytomegalovirus (cCMV) testing in Utah.

STUDY DESIGN

We surveyed 365 caregivers whose children were being seen in an otolaryngology clinic at a tertiary pediatric hospital about their knowledge of and attitudes toward cCMV and cCMV screening. Descriptive statistics and cluster analysis were used to examine their responses.

RESULTS

The majority of caregivers were unsure how cCMV was spread, the symptoms of cCMV, and why cCMV screening of infants was important. Most caregivers did not know that cCMV screening was required by law in Utah if an infant is referred after newborn hearing screening. A majority wanted to know if their child had cCMV even if asymptomatic and were willing to pay $20 for cCMV screening. Caregivers of children who had been tested for cCMV were significantly more likely to be strongly in favor of cCMV screening than expected by chance. Caregivers in the highly knowledgeable cluster were more likely to be strongly in favor of cCMV screening.

CONCLUSIONS

Caregivers frequently were unaware of cCMV and its implications. Attitudes toward cCMV screening generally were positive. Education on epidemiology and impact of cCMV may benefit both prevention of infection and attitudes toward screening.

Seronegative patients vaccinated with cytomegalovirus gB-MF59 vaccine have evidence of neutralising antibody responses against gB early post-transplantation

BACKGROUND

Human cytomegalovirus (HCMV) causes a ubiquitous infection which can pose a significant threat for immunocompromised individuals, such as those undergoing solid organ transplant (SOT). Arguably, the most successful vaccine studied to date is the recombinant glycoprotein-B (gB) with MF59 adjuvant which, in 3 Phase II trials, demonstrated 43-50% efficacy in preventing HCMV acquisition in seronegative healthy women or adolescents and reduction in virological parameters after SOT. However, the mechanism of vaccine protection in seronegative recipients remains undefined.

METHODS

We evaluated samples from the cohort of seronegative SOT patients enroled in the Phase II glycoprotein-B/MF59 vaccine trial who received organs from seropositive donors. Samples after SOT (0-90 days) were tested by real-time quantitative PCR for HCMV DNA. Anti-gB antibody levels were measured by ELISA. Neutralization was measured as a decrease in infectivity for fibroblast cell cultures revealed by expression of immediate-early antigens.

FINDINGS

Serological analyses revealed a more rapid increase in the humoral response against gB post transplant in vaccine recipients than in those randomised to receive placebo. Importantly, a number of patient sera displayed HCMV neutralising responses - neutralisation which was abrogated by pre-absorbing the sera with recombinant gB.

INTERPRETATION

We hypothesise that the vaccine primed the immune system of seronegative recipients which, when further challenged with virus at time of transplant, allowed the host to mount rapid immunological humoral responses even under conditions of T cell immune suppression during transplantation.

The Current Status of Cytomegalovirus (CMV) Prevalence in the MENA Region: A Systematic Review

Human cytomegalovirus (CMV) is a highly prevalent herpesvirus worldwide. According to the Centers for Disease Control and Prevention (CDC) and the World Health Organization (WHO), CMV infects people of all ages, and by the age of five, approximately one-third of children in the United States are infected. Although the infection is generally asymptomatic, it can cause severe disease in immunocompromised patients, transplant and transfusion recipients, as well as newborn neonates. The objective of this study is to systematically review published literature on CMV in the MENA region to estimate its incidence in the region and describe its epidemiological and clinical significance. The literature was searched through four scientific databases: PubMed, Scopus, Science Direct, and Web of Science. A total of 72 studies from 11 countries satisfied the inclusion criteria, covering a period from 1988-2019. The CMV IgG seroprevalence ranged from 8.7%-99.2% (SD = 38.95%). CMV incidence in these countries ranged between 1.22% and 77% in transplant and transfusion recipients, with an increase in incidence with advanced age. However, the incidence rate was unclear for congenital CMV due to the variability of the reporting. This review highlights the need for more robust and well-designed studies to better estimate CMV incidence in the MENA region, standardize diagnostic criteria, and consider prophylactic and pre-emptive treatments to limit the morbidity and mortality of the disease.

Impact of Maternal Immunity on Congenital Cytomegalovirus Birth Prevalence and Infant Outcomes: A Systematic Review

Congenital cytomegalovirus (cCMV) is the leading non-genetic cause of sensorineural hearing loss (SNHL), and efforts are geared towards prevention through vaccine development. Transmission rates following primary maternal infection occur at rates of 30-40%, however reported placental rates upon non-primary maternal infection is reported to be less than <4%. There is significant debate about whether this reduction in transmission rate is due to pre-existing maternal immunity, which could identify possible immunologic targets for vaccines. To address this question, we performed a systemic review of the literature using Preferred Reporting Items for Systematic Review and Analysis (PRISMA) guidelines. We identified cohort studies in high CMV seroprevalent (>80%) areas or in developing regions that examined a cohort of at least 50 infants for congenital CMV acquisition. We identified 19 articles that met criteria and were further categorized based on pre-conception serology, maternal seroprevalence, or previously known seroprevalence. Birth prevalence rates ranged from 0.4% to 6% (median 1.1%), with the studies reporting on clinical outcome (16/19 studies) noting the majority of infected infants as asymptomatic. We also utilized a recent study that differentiated primary maternal infections from chronic infections in a highly seropositive population to calculate a placental transmission rate in women with pre-existing immunity compared to that of no pre-existing immunity. This work confirms a low cCMV birth prevalence in highly seropositive populations, indicates via a calculated placental transmission rate that the CMV placental transmission rate is lower in non-primary infection than that of primary infection, and reveals gaps in data for further research aiming to identify targets for vaccine development.

Genotypes of glycoprotein B gene among the Indian symptomatic neonates with congenital CMV infection

BACKGROUND

Cytomegalovirus [CMV] is a causative agent of congenital infection worldwide and often leads to neurological deficits and hearing loss in newborns. Infants born with symptomatic congenital Cytomegalovirus infection [cCMV] are at significant high risk for developing adverse long-term outcomes. In this study, we look into the sequence variability of surface glycoprotein B [gB] encoding region in newborns with symptomatic CMV infection for the first time in Eastern region of India.

METHODS

576 suspected newborns from seropositive mothers were subjected to the study and ELISA was used to confirm CMV infection. Different genotypes and their subtypes were determined using multiplex nested-PCR. Viral load of different glycoprotein B [gB] genotypes was measured using RT-PCR. Sequencing and phylogenetic analysis was then performed using Bayesian interference.

RESULTS

The overall frequency of cCMV infection was 18.4%, where 16.0% neonates were symptomatic. Among the different gB genotypes, gB1 had the highest frequency [23.5%] and gB4 showed the lowest occurrence [5.8%]. 23.5% of symptomatic neonates had mixed genotypes of gB, probably indicating matrenal reinfection with CMV strains in Indian population. Significant genotypic clades [gB1-gB2-gB3-gB5] were grouped closely based on gene sequences, but the gB4 sequence was in the outlier region of the phylogenetic tree indicating the genetic polymorphism.

CONCLUSION

This is the first study on cCMV genotyping and its phylogenetic analysis from Eastern Indian neonatal population. The study holds importance in the assessment of cCMV seroprevalence in global perspective. gB protein can be used as a potential therapeutic target against CMV infection.

Natural Inhibitor of Human Cytomegalovirus in Human Seminal Plasma

Human cytomegalovirus (HCMV) is the most frequent viral cause of congenital infections that can lead to severe birth defects. Although HCMV is frequently detected in semen and thus is potentially sexually transmitted, the role of semen in HCMV transmission is largely unclear. Here we describe that human seminal plasma (SP; the cell-free supernatant of semen) inhibits HCMV infection. The inhibition of HCMV infection was dose dependent and effective for different cell types, virus strains, and semen donors. This inhibitory effect was specific for HCMV, as herpes simplex virus 2 (HSV-2) and human immunodeficiency virus type 1 (HIV-1) infections were enhanced by SP. Mechanistically, SP inhibited infection by interfering with the attachment of virions to cells most likely via an interaction with the trimeric glycoprotein complex gH/gL/gO. Together, our findings suggest that semen contains a factor that potentially limits sexual transmission of HCMV.IMPORTANCE The role of semen in sexual transmission of human cytomegalovirus (HCMV) is currently unclear. This is surprising, as HCMV is frequently detected in this body fluid and infection is of high danger for neonates and pregnant women. In this study, we found that seminal plasma (SP) dose dependently inhibited HCMV infection. The infection inhibition was specific for HCMV, as other viruses, such as human immunodeficiency virus type 1 (HIV-1) and herpes simplex virus 2 (HSV-2), were not inhibited by SP. SP must contain a soluble, heat-resistant factor that limits attachment of HCMV particles to cells, probably by interaction with the trimeric glycoprotein complex gH/gL/gO. This novel virus-host interaction could possibly limit transmission of HCMV via semen during sexual intercourse.

Brain Magnetic Resonance Imaging Findings of Congenital Cytomegalovirus Infection as a Prognostic Factor for Neurological Outcome

BACKGROUND

The aim of this study is to predict the neurological outcomes of patients with congenital cytomegalovirus infection by analysis of magnetic resonance images of the brain.

METHODS

From June 2007 to June 2016, 31 patients were diagnosed with symptomatic congenital cytomegalovirus infection at Asan Medical Center. The medical records and magnetic resonance imaging (MRI) findings of these patients were reviewed, and the relationships between MRI findings and neurological outcomes were analyzed.

RESULTS

Of the 31 patients, 17 were male and 12 were born prematurely (gestation age less than 37 weeks). Twenty-one patients presented with delayed development, 11 with microcephaly, and 10 with sensorineural hearing loss. Eleven patients developed epilepsy. The most common abnormal findings on brain MRI were ventriculomegaly (N = 21, 67.7%) and polymicrogyria (N = 14, 45.2%). Delayed development significantly correlated with the presence of polymicrogyria (P = 0.001). Epilepsy was significantly associated with polymicrogyria (P = 0.012), ventriculomegaly (P = 0.045), calcification (P = 0.006), and white matter abnormalities (P = 0.018). Sensorineural hearing loss was not associated with any abnormal findings on brain MRI. Based on these data, a new brain magnetic resonance cytomegalovirus scoring scale was built and this scoring scale can predict the development of epilepsy with odds ratio 3.62 (confidence interval 1.52 to 8.67, P = 0.004).

CONCLUSIONS

In patients with congenital cytomegalovirus infections, brain MRI abnormalities could predict poor developmental outcomes and epilepsy, but not sensorineural hearing loss. Stratified magnetic resonance findings can be suggested as the predictors of neurological outcomes in individuals with congenital cytomegalovirus infections.

Neonates with congenital Cytomegalovirus and hearing loss identified via the universal newborn hearing screening program

BACKGROUND

Congenital cytomegalovirus (CMV) is the most common non-genetic cause of sensorineural hearing loss. Currently, there are no universal CMV screening programs for newborns or routine CMV testing of neonates with hearing loss in Australia, or elsewhere.

OBJECTIVES

This study was undertaken to determine the prevalence of congenital CMV infection in infants with hearing loss identified using routine resources via the Australian universal neonatal hearing screening (UNHS) program.

STUDY DESIGN

Infants who failed UNHS, referred for audiological testing and found to have permanent hearing loss were screened for CMV via PCR of urine and saliva. Congenital CMV was diagnosed if CMV was detected in infants ≤30 days of age, or using retrospective testing on stored new born screening cards, retrospective testing, or using clinical criteria if >30 days of age. The cohort was analyzed for time of testing and prevalence of congenital CMV determined.

RESULTS

The Audiology Department reviewed 1669 infants who failed UNHS between 2009 and 2016. Thirty percent (502/1669) had permanent hearing loss confirmed, of whom 336/502 were offered CMV testing. A definite (n = 11) or probable (n = 8) diagnosis of congenital CMV occurred in 19/323 (5.9%), of whom definite diagnoses were made in 4/19 on tests positive prior to 21 days of life, in 5/19 who were positive on neonatal blood screening card (NBSC) testing, in 2/19 who were positive on placental testing. In 8/19 probable diagnoses were made based on positive testing between ages 23-42 days and a consistent clinical syndrome in the absence of another cause for hearing loss after genetic and other testing. CMV testing mirrored the timing of audiological testing, with ∼40% completing audiology and CMV testing by 21 days, and 64% by 30 days.

CONCLUSION

This program, utilizing existing clinical services identified probable congenital CMV in ∼6% of a large cohort failing UNHS with permanent hearing loss, of whom more than half were definite diagnoses. No additional assets were required to those already existing in this tertiary referral pediatric centre, whilst providing useful and timely data for clinical and audiological management.

Prevalence and clinical profile of microcephaly in South America pre-Zika, 2005-14: prevalence and case-control study

Objective To describe the prevalence and clinical spectrum of microcephaly in South America for the period 2005-14, before the start of the Zika epidemic in 2015, as a baseline for future surveillance as the Zika epidemic spreads and as other infectious causes may emerge in future.Design Prevalence and case-control study.Data sources ECLAMC (Latin American Collaborative Study of Congenital Malformations) database derived from 107 hospitals in 10 South American countries, 2005 to 2014. Data on microcephaly cases, four non-malformed controls per case, and all hospital births (all births for hospital based prevalence, resident within municipality for population based prevalence). For 2010-14, head circumference data were available and compared with Intergrowth charts.Results 552 microcephaly cases were registered, giving a hospital based prevalence of 4.4 (95% confidence interval 4.1 to 4.9) per 10 000 births and a population based prevalence of 3.0 (2.7 to 3.4) per 10 000. Prevalence varied significantly between countries and between regions and hospitals within countries. Thirty two per cent (n=175) of cases were prenatally diagnosed; 29% (n=159) were perinatal deaths. Twenty three per cent (n=128) were associated with a diagnosed genetic syndrome, 34% (n=189) polymalformed without a syndrome diagnosis, 12% (n=65) with associated neural malformations, and 26% (n=145) microcephaly only. In addition, 3.8% (n=21) had a STORCH (syphilis, toxoplasmosis, other including HIV, rubella, cytomegalovirus, and herpes simplex) infection diagnosis and 2.0% (n=11) had consanguineous parents. Head circumference measurements available for 184/235 cases in 2010-14 showed 45% (n=82) more than 3 SD below the mean, 24% (n=44) between 3 SD and 2 SD below the mean, and 32% (n=58) larger than -2 SD.Conclusion Extrapolated to the nearly 7 million annual births in South America, an estimated 2000-2500 microcephaly cases were diagnosed among births each year before the Zika epidemic began in 2015. Clinicians are using more than simple metrics to make microcephaly diagnoses. Endemic infections are important enduring causes of microcephaly.

Disturbance in Plasma Metabolic Profile in Different Types of Human Cytomegalovirus-Induced Liver Injury in Infants

Human cytomegalovirus (HCMV) infection in infants is a global problem and the liver is a target organ of HCMV invasion. However, the mechanism by which HCMV causes different types of liver injury is unclear, and there are many difficulties in the differential diagnosis of HCMV infantile cholestatic hepatopathy (ICH) and extrahepatic biliary atresia (EHBA). We established a non-targeted gas chromatography-mass spectrometry metabolomics method in conjunction with orthogonal partial least squares-discriminate analysis based on 127 plasma samples from healthy controls, and patients with HCMV infantile hepatitis, HCMV ICH, and HCMV EHBA to explore the metabolite profile of different types of HCMV-induced liver injury. Twenty-nine metabolites related to multiple amino acid metabolism disorder, nitrogen metabolism and energy metabolism were identified. Carbamic acid, glutamate, L-aspartic acid, L-homoserine, and noradrenaline for HCMV ICH vs. HCMV EHBA were screened as potential biomarkers and showed excellent discriminant performance. These results not only revealed the potential pathogenesis of HCMV-induced liver injury, but also provided a feasible diagnostic tool for distinguishing EHBA from ICH.

Human Cytomegalovirus Modulates Expression of Noncanonical Wnt Receptor ROR2 To Alter Trophoblast Migration

Maternal primary cytomegalovirus (CMV) infection, reactivation, or reinfection with a different viral strain may cause fetal injury and adverse pregnancy outcomes. Increasing evidence indicates that fetal injury results not only from direct viral cytopathic damage to the CMV-infected fetus but also from indirect effects through placental infection and dysfunction. CMV alters Wingless (Wnt) signaling, an essential cellular pathway involved in placentation, as evidenced by reduced transcription of canonical Wnt target genes and decreased Wnt3a-induced trophoblast migration. Whether CMV affects the noncanonical Wnt signaling pathway has been unclear. This study demonstrates for the first time that CMV infection inhibits Wnt5a-stimulated migration of human SGHPL-4 trophoblasts and that inhibition of the pathway restores normal migration of CMV-infected cells. Western blot and real-time PCR analyses show increased expression of noncanonical Wnt receptor ROR2 in CMV-infected trophoblasts. Mimicking the CMV-induced ROR2 protein expression via ectopic expression inhibited Wnt5a-induced trophoblast migration and reduced T cell-specific factor (TCF)/lymphoid enhancer-binding factor (LEF)-mediated transcription as measured using luciferase reporter assays. Gene silencing using small interfering RNA (siRNA) duplexes decreased ROR2 transcript and protein levels. In contrast, proliferation of SGHPL-4 trophoblasts, measured by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay was not affected. The siRNA-mediated downregulation of ROR2 in trophoblasts rescued CMV-induced reduction in trophoblast migration. These data suggest a mechanism where CMV alters the expression of the Wnt receptor ROR2 to alter Wnt5a-mediated signaling and inhibit trophoblast motility. Inhibition of this mechanism may be a target for therapeutic intervention for CMV-induced placental damage and consequent fetal damage in congenital CMV infections.

IMPORTANCE

Maternal primary cytomegalovirus (CMV) infection, reactivation, or reinfection with a different viral strain may cause fetal injury and adverse pregnancy outcomes. Increasing evidence indicates that fetal injury results not only from direct viral cytopathic damage to the CMV-infected fetus but also from indirect effects through placental infection and placental dysfunction. No effective therapy is currently proven to prevent or treat congenital CMV infection. Understanding the molecular underpinnings of CMV infection of the placenta is essential for therapeutic innovations and vaccine design. CMV alters canonical Wingless (Wnt) signaling, an essential cellular pathway involved in placental development. This study suggests a mechanism in which CMV alters the expression of noncanonical Wnt receptor ROR2 to alter motility of placental cells, which has important implications in the pathogenesis of CMV-induced placental dysfunction. Inhibition of this mechanism may be a target for therapeutic intervention for CMV-induced placental damage and consequent fetal damage in congenital CMV infection.