Overview of congenitally and perinatally acquired cytomegalovirus infections: recent advances in antiviral therapy

Lenticulostriate Vasculopathy in Brain Ultrasonography is Associated with Cytomegalovirus Infection in Newborns

BACKGROUND

Lenticulostriate vasculopathy is associated with various disorders, in particular cytomegalovirus infection, which can cause neurological consequences. We wanted to evaluate the association of lenticulostriate vasculopathy and cytomegalovirus infection. We retrospectively collected data on lenticulostriate vasculopathy from 858 neonatal ultrasonography scans.

METHODS

Fifty-five patients with lenticulostriate vasculopathy were diagnosed. Lenticulostriate vasculopathy was classified as severe and mild according to the ultrasonographic findings. We analyzed gender, unilateral and bilateral lenticulostriate vasculopathy, mild and severe lenticulostriate vasculopathy, intrauterine growth retardation, and lenticulostriate vasculopathy associated with other brain malformations to determine whether they were correlated with cytomegalovirus infection.

RESULTS

Neonatal cytomegalovirus infections correlated primarily with lenticulostriate vasculopathy that was associated with brain structure anomalies p < 0.0001, followed by severe lenticulostriate vasculopathy (p = 0.029). Cytomegalovirus urine polymerase chain reaction ratios were 69% for severe and 23% for mild lenticulostriate vasculopathy (p = 0.002; odds ratio = 7.33). Of 72 newborns with intrauterine growth retardation without lenticulostriate vasculopathy, 33 were analyzed for cytomegalovirus, of whom only one was positive, which was significantly different from the newborns with lenticulostriate vasculopathy (p = 0.003; odds ratio = 11.64).

CONCLUSION

Lenticulostriate vasculopathy on neonatal ultrasonography is useful for predicting cytomegalovirus infection, particularly in severe lenticulostriate vasculopathy. When severe lenticulostriate vasculopathy is associated with a brain structure anomaly, cytomegalovirus infection should be considered. The outcomes for the cases in which cytomegalovirus infection was associated with other brain structure anomalies were significantly worse than the outcomes in cases associated with lenticulostriate vasculopathy only.

CMV-induced embryonic mouse organ of corti dysplasia: Network architecture of dysfunctional lateral inhibition

BACKGROUND

Congenital cytomegalovirus infection is the major nongenetic cause of sensorineural hearing loss at birth and beyond. Among other pathologies, there is a striking dysplasia/hyperplasia of organ of Corti hair and supporting cells.

METHODS

Using an in vitro embryonic mouse model of cytomegalovirus-induced cochlear teratogenesis that mimics the known human pathology, and functional signaling network modeling, we tested the hypothesis that cytomegalovirus disrupts the highly ordered organ of Corti hair and supporting cells pattern by dysregulating Notch and Fgfr3, their cognate ligands and downstream effectors.

RESULTS

Several novel emergent properties of the critical lateral inhibition subnetwork became apparent. The subnetwork has classic small-world properties such as short paths between most gene pairs, few long-distance links, and considerable clustering. Concomitantly, the calculated probability that our specific gene expression dataset is from dysplastic organs of Corti is highly significant (p < 1 × 10(-12) ). Furthermore, we determined that the subnetwork has a highly heterogeneous scale-free topology in which the highly linked genes (hubs), Notch and Fgfr3, play a central role in mediating interactions among the less linked genes.

CONCLUSION

This phenomenon has important biologic and therapeutic implications.

Recent advances in designing an effective vaccine to prevent cytomegalovirus-associated clinical diseases

It is now well over a decade since the US Institute of Medicine of the National Academy of Sciences assigned the highest priority for a vaccine to prevent congenital human CMV infection, which was subsequently endorsed by the US National Vaccine Program Office. In spite of extensive efforts over many years, successful licensure of a CMV vaccine formulation remains elusive. While the understanding of immune regulation of CMV infection in healthy virus carriers and diseased patients has dramatically improved, traditional vaccine development programs have failed to exploit this knowledge. Until recently, most efforts have concentrated on designing vaccine formulations that block CMV infection through neutralizing antibodies. However, studies carried out in various disease settings, especially in transplant patients, have clearly emphasized the importance of cellular immunity and it is indeed encouraging to see that recent CMV vaccine development programs have started to incorporate this arm of the immune system. A number of new vaccine candidates have been found to be effective in preclinical studies, and are able to induce CMV-specific immune responses in clinical studies, although firm evidence for long-term efficacy is not yet available. For successful implementation of these vaccines in clinical settings, it will be important to demonstrate that the vaccine can induce effective levels of immunity for prevention of transmission of viral infection from mother to unborn baby and thus reduce CMV-related pathogenesis. For transplant recipients, vaccine strategies should be aimed at the induction of immunity that restricts viral reactivation and limits development of disease.

Evaluation of intratympanic formulations for inner ear delivery: methodology and sustained release formulation testing

A convenient and efficient in vitro diffusion cell method to evaluate formulations for inner ear delivery via the intratympanic route is currently not available. The existing in vitro diffusion cell systems commonly used to evaluate drug formulations do not resemble the physical dimensions of the middle ear and round window membrane. The objectives of this study were to examine a modified in vitro diffusion cell system of a small diffusion area for studying sustained release formulations in inner ear drug delivery and to identify a formulation for sustained drug delivery to the inner ear. Four formulations and a control were examined in this study using cidofovir as the model drug. Drug release from the formulations in the modified diffusion cell system was slower than that in the conventional diffusion cell system due to the decrease in the diffusion surface area of the modified diffusion cell system. The modified diffusion cell system was able to show different drug release behaviors among the formulations and allowed formulation evaluation better than the conventional diffusion cell system. Among the formulations investigated, poly(lactic-co-glycolic acid)-poly(ethylene glycol)-poly(lactic-co-glycolic acid) triblock copolymer systems provided the longest sustained drug delivery, probably due to their rigid gel structures and/or polymer-to-cidofovir interactions.

Letermovir Treatment of Human Cytomegalovirus Infection Antiinfective Agent

Novel therapies are urgently needed for the management of cytomegalovirus (CMV) disease in high-risk patients. Currently licensed agents target the viral DNA polymerase, and although they are effective, they are fraught with toxicities to patients. Moreover, emergence of antiviral resistance is an increasing problem, particularly for patients on long-term suppressive therapy. A new agent, letermovir (AIC246), shows great promise for the management of CMV infection. Advantages include its good oral bioavailability, its lack of toxicity, and the apparent absence of drug-drug interactions. Letermovir has a novel mechanism of action, exerting its antiviral effect by interfering with the viral pUL56 gene product and in the process disrupting the viral terminase complex. This agent demonstrates substantial promise as an alternative to more toxic antivirals in patients at high risk for CMV disease, particularly in the transplantation setting.

Severe postnatal cytomegalovirus infection with multisystem involvement in an extremely low birth weight infant

Cytomegalovirus (CMV) infection is the most common intrauterine and perinatal viral infection. Postnatal CMV infection is acquired mainly from breast milk and may cause severe illness in preterm infants. We report an extremely low birth weight infant who presented with a sepsis-like syndrome and multiple organ involvement, notably hepatitis and pneumonitis, and treated with ganciclovir without adverse effect or relapse.

Severe morbidity and mortality with breast milk associated cytomegalovirus infection

Congenital cytomegalovirus (CMV) infection can cause significant morbidity and mortality in the newborn period. Postnatally acquired CMV infection has been thought to carry much less morbidity. We report 5 cases of severe morbidity and mortality in very low birth weight infants with postnatally acquired, breast milk associated CMV infection.

Encephalitis, acute renal failure, and acute hepatitis triggered by a viral infection in an immunocompetent young adult: a case report

Introduction

Cytomegalovirus generally causes self-limited, mild and asymptomatic infections in immunocompetent patients. An aggressive course in immunocompetent healthy patients is unusual.

Case presentation

We report the case of an immunocompetent 16-year-old Egyptian boy with encephalitis, acute renal failure, and acute hepatitis triggered by viral infection with a complete recovery following antiviral treatment.

Conclusion

We believe that this case adds to the understanding of the molecular biology, clinical presentation and increasing index of suspicion of many viral infections.

Antiviral therapy for herpesvirus central nervous system infections: neonatal herpes simplex virus infection, herpes simplex encephalitis, and congenital cytomegalovirus infection

Herpesvirus infections of the central nervous system (CNS) are a significant cause of morbidity and mortality, including long-term neurologic sequelae. Among the family of herpesviruses, the most significant CNS infections are due to herpes simplex virus (HSV) and cytomegalovirus (CMV). The onset of HSV CNS infection can occur in neonates as well as older children and adults. CNS infection associated with CMV occurs predominantly in the perinatal period, but may also be seen rarely in children and adults, especially in immunocompromised individuals. Although advances in antiviral agents have led to improved outcomes, there is still a need for more effective treatments.

Fetal ascites owing to congenital cytomegalovirus: response to ganciclovir

A term newborn with severe congenital cytomegalovirus (CMV) infection is described. Fetal ascites was detected at 28 weeks gestation, and at birth there was tense ascites. There was intra-uterine growth retardation, microcephaly, chorioretinitis, jaundice, purpura and pneumonitis. Computed tomographic scan of the brain showed ventriculomegaly with periventricular calcifications. Serology was positive for cytomegalovirus-specific immunoglobulin M, and cytomegalovirus DNA was detected in the ascitic fluid and urine by nested polymerase chain reaction. He received 6 weeks of treatment with ganciclovir. Ascites resolved spontaneously and liver function tests became normal. Although there was a good clinical response to ganciclovir therapy without any side-effects, on follow-up the infant had global developmental delay and bilateral sensorineural deafness.

Abnormally expanded pro-B hematogones associated with congenital cytomegalovirus infection

Hematogones are nonleukemic immature lymphocytes that display a B-precursor phenotype and populate the pediatric bone marrow. We present the case of a newborn with an atypical, marked expansion of hematogones similar to the pro-B cells of infant acute lymphoblastic leukemia, which demonstrated their nonleukemic nature through gene rearrangement analysis and were associated with a congenital cytomegalovirus infection.

Early acquisition of herpes simplex virus type 1 antibodies in children—A longitudinal serological study

BACKGROUND

Herpes simplex virus type 1 (HSV-1) infections are commonly acquired in childhood, asymptomatically or as a symptomatic infection. However, little is known about the time of HSV seroconversion during infancy and early childhood.

OBJECTIVE

To investigate the acquisition of IgG-antibodies to HSV in infants and children.

STUDY DESIGN

A longitudinal study, using type-specific HSV-1 and herpes simplex virus type 2 (HSV-2) enzyme-linked immunosorbent assays on sera collected from the mother and from their child at the age of 3, 5, 6, 12, 13 and 30 months.

RESULTS

The maternal seroprevalences for HSV-1 was 65% and for HSV-2 19%. A gradual loss of maternal antibodies was seen, with few infants having detectable HSV-1 antibodies at the age of 1 year. A more rapid decline was registered for HSV-2 antibodies. A small number of new HSV-1 infections occurred in 3-5-month olds and more than half of the new infections were detected before the age of 13 months. At the age of 30 months, 30% of the children were HSV-1 antibody positive.

CONCLUSION

Seroconversion to HSV-1 commonly occurs already during infancy, suggesting that HSV-1 is transmitted primarily from parent to child.

Risk factors for and clinical outcome of congenital cytomegalovirus infection in a peri-urban West-African birth cohort

BACKGROUND

Congenital cytomegalovirus (CMV) infection is the most prevalent congenital infection worldwide. Epidemiology and clinical outcomes are known to vary with socio-economic background, but few data are available from developing countries, where the overall burden of infectious diseases is frequently high.

METHODOLOGY/PRINCIPAL FINDINGS

As part of an ongoing birth cohort study in The Gambia among term infants, urine samples were collected at birth and tested by PCR for the presence of CMV DNA. Risk factors for transmission and clinical outcome were assessed, including placental malaria infection. Babies were followed up at home monthly for morbidity and anthropometry, and at one year of age a clinical evaluation was performed. The prevalence of congenital CMV infection was 5.4% (40/741). A higher prevalence of hepatomegaly was the only significant clinical difference at birth. Congenitally infected children were more often first born babies (adjusted odds ratio (OR) 5.3, 95% confidence interval (CI) 2.0-13.7), more frequently born in crowded compounds (adjusted OR 2.9, 95%CI 1.0-8.3) and active placental malaria was more prevalent (adjusted OR 2.9, 95%CI 1.0-8.4). These associations were corrected for maternal age, bed net use and season of birth. During the first year of follow up, mothers of congenitally infected children reported more health complaints for their child.

CONCLUSIONS/SIGNIFICANCE

In this study, the prevalence of congenital CMV among healthy neonates was much higher than previously reported in industrialised countries, and was associated with active placental malaria infection. There were no obvious clinical implications during the first year of life. The effect of early life CMV on the developing infant in the Gambia could be mitigated by environmental factors, such as the high burden of other infections.

Cytomegalovirus infection of human syncytiotrophoblast cells strongly interferes with expression of genes involved in placental differentiation and tissue integrity

The principle route of acquisition of cytomegalovirus (CMV) for the fetus is believed to be via the placenta. We subjected purified cytotrophoblast cells obtained from full-term placentas to CMV infection and examined placental gene expression using microarray analyses. Cytotrophoblast cells purified from term placentas differentiated in vitro into a multinucleated syncytium that could be productively infected with CMV, with peak virus titers of approximately 10 plaque-forming units (PFU)/mL identified in supernatants at late time points postinoculation. Infected syncytiotrophoblast cells expressed CMV-specific transcripts and proteins, as demonstrated by Northern blot and immunofluorescence assays. Microarray analyses revealed that CMV infection strongly and reproducibly altered trophoblast gene expression, elevating expression of mitotic cell cycle genes, and repressing expression of genes associated with trophoblast differentiation, particularly those associated with formation and stabilization of the extracellular matrix. We conclude that purified, differentiated syncytiotrophoblasts are permissive for CMV replication. Infection of these cells induces significant perturbations in trophoblast transcription. An improved understanding of the molecular events that occur during CMV infection of trophoblasts could provide insights into interventions that might prevent or minimize congenital transmission.

Successful treatment with oral valganciclovir in immunocompetent infant with gastrointestinal manifestations of cytomegalovirus infection

A 3-month-old male infant was admitted to hospital with anemia. Follow-up controls revealed the presence of specific cytomegalovirus (CMV) antibodies. Virus was isolated from urine, blood, and saliva. At 7 months of age, he presented with melena. Polymerase chain reaction (PCR) of biopsy samples from the duodenum was positive for CMV. Anemia resolved after starting antiviral therapy with oral valganciclovir.

Control of human cytomegalovirus gene expression by differential histone modifications during lytic and latent infection of a monocytic cell line

Non-differentiated THP-1 cells can be infected by human cytomegalovirus (HCMV) Towne strain, which persists in these cells in a non-active (latent) form without undergoing a productive cycle. The same cells become permissive for HCMV lytic infection after induction of cell differentiation by treatment with 12-O-tetradecanoylphorbol-13-acetate. We used this cellular model to study the possible role of histone modifications in the control of HCMV latency. Using chromatin immunoprecipitation with antibodies against histone H3 acetylated or dimethylated in position K9, we demonstrated that in lytically infected cells the HCMV enhancer was associated with heavy acetylated but not dimethylated H3. In the case of latent infection, the HCMV enhancer was associated with neither acetylated nor dimethylated H3. HCMV genes encoding DNA polymerase (early), pp65 (early-late) and pp150 (late) proteins were associated preferentially with acetylated H3 in lytically infected cells and with dimethylated H3 in latently infected cells. These data strongly suggest that K9 methylation of H3 is involved in HCMV gene repression, while association of the above genes with acetylated histones is likely to be necessary for active transcription. It can be postulated that the same histone modifications are used to mark active and repressed genes in both cellular and viral chromatin.

Progress toward an elusive goal: current status of cytomegalovirus vaccines

Although infection with human cytomegalovirus (CMV) is ubiquitous and generally asymptomatic in most individuals, certain patient populations are at high risk for CMV-associated disease. These include HIV-infected individuals with AIDS, transplant patients, and newborn infants with congenital CMV infection. Immunity to CMV infection, both in the transplant setting and among women of childbearing age, plays a vital role in the control of CMV-induced injury and disease. Although immunity induced by CMV infection is not completely protective against reinfection, there is nevertheless a sound basis on which to believe that vaccination could help control CMV disease in high-risk patient populations. Evidence from several animal models of CMV infection indicates that a variety of vaccine strategies are capable of inducing immune responses sufficient to protect against CMV-associated illness following viral challenge. Vaccination has also proven effective in improving pregnancy outcomes following CMV challenge of pregnant guinea pigs, providing a 'proof-of-principle' relevant to human clinical trials of CMV vaccines. Although there are no licensed vaccines currently available for human CMV, progress toward this goal has been made, as evidenced by ongoing clinical trial testing of a number of immunization strategies. CMV vaccines currently in various stages of preclinical and clinical testing include: protein subunit vaccines; DNA vaccines; vectored vaccines using viral vectors, such as attenuated pox- and alphaviruses; peptide vaccines; and live attenuated vaccines. This review summarizes some of the obstacles that must be overcome in development of a CMV vaccine, and provides an overview of the current state of preclinical and clinical trial evaluation of vaccines for this important public health problem.

Acquisition of human cytomegalovirus infection in infants via breast milk: natural immunization or cause for concern?

Since the recognition in the 1960s that human cytomegalovirus (HCMV) infections could be transmitted by breast milk, there has been relatively little attention paid to the potential medical consequences of such infections. Indeed, since HCMV infections acquired by healthy newborn infants appear to be largely asymptomatic in nature, there has been no real incentive to develop or implement strategies to prevent transmission by this route. However, recent studies have identified a significant risk for low-birth weight, premature infants for the development of HCMV disease following acquisition of infection via breast milk. Such infections may cause considerable short-term morbidity and, in some cases, severe, life-threatening illness. There is little consensus amongst neonatologists on the approach to prevention and management of such infections. This review summarises the epidemiology and natural history of HCMV infections acquired via breast milk, and outlines available strategies for prevention and management of such infections, as well as opportunities for future clinical research on this understudied topic.

Cyclic cidofovir (cHPMPC) prevents congenital cytomegalovirus infection in a guinea pig model

Background

Congenital cytomegalovirus (CMV) infection is a major public health problem. Antiviral therapies administered during pregnancy might prevent vertical CMV transmission and disease in newborns, but these agents have not been evaluated in clinical trials. The guinea pig model of congenital CMV infection was therefore used to test the hypothesis that antiviral therapy, using the agent agent cyclic cidofovir (cHPMPC), could prevent congenital CMV infection.

Results

Pregnant outbred Hartley guinea pigs were challenged in the early-third trimester with guinea pig CMV (GPCMV) and treated with placebo, or the antiviral agent, cyclic cidofovir. To optimize detection of vertical infection, an enhanced green fluorescent protein (eGFP)-tagged virus was employed. Compared to placebo, cyclic cidofovir-treated dams and pups had reduced mortality following GPCMV challenge. The magnitude of GPCMV-induced maternal and fetal mortality in this study was reduced from 5/25 animals in the placebo group to 0/21 animals in the treatment group (p = 0.05, Fisher's exact test). By viral culture assay, antiviral therapy was found to completely prevent GPCMV transmission to the fetus. In control pups, 5/19 (26%) were culture-positive for GPCMV, compared to 0/16 of pups in the cyclic cidofovir treatment group (p < 0.05, Fisher's exact test).

Conclusion

Antiviral therapy with cyclic cidofovir improves pregnancy outcomes in guinea pigs, and eliminates congenital CMV infection, following viral challenge in the third trimester. This study also demonstrated that an eGFP-tagged recombinant virus, with the reporter gene inserted into a dispensable region of the viral genome, retained virulence, including the potential for congenital transmission, facilitating tissue culture-based detection of congenital infection. These observations provide support for clinical trials of antivirals for reduction of congenital CMV infection.

Multiplex real-time PCR assay for simultaneous quantitation of human cytomegalovirus and herpesvirus-6 in polymorphonuclear and mononuclear cells of transplant recipients

Human cytomegalovirus (HCMV) and human herpesvirus-6 (HHV-6) are two closely related viruses, which belong to the Herpesviridae family. Following primary infection, they are thought to persist for life as latent forms in mononuclear cells. HCMV and HHV-6 can cause considerable morbidity in immunocompromised individuals, such as transplant patients. A sensitive and specific LightCycler multiplex real-time PCR assay based on fluorescence energy transfer (known as FRET) was developed. This assay, by using two sets of hybridization probes specific for HHV-6 (A and B) and HCMV, can differentiate reliably and quantify simultaneously both viruses in order to diagnose reactivation processes. The assay was optimized and the lower limit of detection for both viruses was determined to be 10 viral genome copies per reaction. Both viruses were quantified in 83 peripheral blood mononuclear cells (PBMCs) and 87 polymorphonuclear leukocytes (PMNLs) collected from 32 transplant recipients. This multiplex real-time quantitative PCR was finally compared with two other quantitation and detection assays used daily in laboratory (PCR DIG detection and antigenemia for HCMV, TaqMan Assay for HHV-6). This technique can be useful for the differentiation and quantitation of HCMV and HHV-6 for monitoring transplant patients.

Nonimmune hydrops fetalis and fulminant fatal disease due to congenital cytomegalovirus infection in a premature infant

We report a case of fatal congenital cytomegalovirus (CMV) disease in a 695 gm, 29 weeks estimated gestational age premature infant. The newborn presented with hydrops fetalis, an unusual presentation of congenital CMV infection. In spite of ganciclovir therapy, the infant succumbed to his illness. Autopsy findings revealed the presence of widespread CMV disease, including pneumonitis, enteritis, and myocarditis. Congenital CMV infection should be considered in the differential diagnosis of hydrops fetalis.

Successful renal transplantation during pregnancy

Little is known about the implications of performing a renal transplant on a patient who is already pregnant. This case study reports a successful outcome of pregnancy, diagnosed coincidentally following renal transplantation at 13 weeks gestation. The recipient was a 23-year-old woman with chronic kidney disease who received a live-related renal transplant from her father. Pregnancy was discovered at routine ultrasound scanning of the renal allograft at 5 days posttransplant and estimated at 13 weeks gestation. She received ciclosporin monotherapy as immunosuppression throughout the pregnancy, and was given valacyclovir as prophylaxis against cytomegalovirus (CMV) infection. Renal function remained stable throughout the pregnancy, which progressed normally, resulting in the vaginal delivery of a healthy, liveborn male infant at 37 weeks gestation. This case study demonstrates that transplantation during pregnancy can have a successful outcome.

The non-nucleoside antiviral, BAY 38-4766, protects against cytomegalovirus (CMV) disease and mortality in immunocompromised guinea pigs

New antiviral drugs are needed for the treatment of cytomegalovirus (CMV) infections, particularly in immunocompromised patients. These studies evaluated the in vitro and in vivo activity of the non-nucleosidic CMV inhibitor, BAY 38-4766, against guinea pig cytomegalovirus (GPCMV). Plaque reduction assays indicated that BAY 38-4766 was active against GPCMV, with an IC(50) of 0.5muM. Yield reduction assays demonstrated an ED(90) and ED(99) of 0.4 and 0.6muM, respectively, of BAY 38-4766 against GPCMV. Guinea pigs tolerated oral administration of 50mg/kg/day of BAY 38-4766 without evidence of biochemical or hematologic toxicity. Plasma concentrations of BAY 38-4766 were high following oral dosing, with a mean peak level at 1-h post-dose of 26.7mg/ml (n=6; range, 17.8-35.4). Treatment with BAY 38-4766 reduced both viremia and DNAemia, as determined by a real-time PCR assay, following GPCMV infection of cyclophosphamide-immunosuppressed strain 2 guinea pigs (p<0.05, Mann-Whitney test). BAY 38-4766 also reduced mortality following lethal GPCMV challenge in immunosuppressed Hartley guinea pigs, from 83% (20/24) in placebo-treated guinea pigs, to 17% (4/24) in BAY 38-4766-treated animals (p<0.0001, Fisher's exact test). Mortality differences were accompanied by reduction in DNAemia in Hartley guinea pigs. Based upon its favorable safety, pharmacokinetic, and therapeutic profiles, BAY 38-4766 warrants further investigation in the GPCMV model.

Antiviral therapy of congenital cytomegalovirus infection

Congenital infection caused by human cytomegalovirus (CMV) is a common occurrence, but its significance is underappreciated. In the developed world, congenital CMV infection confers a tremendous medical and economic burden on society. In recent years, appreciation of the scope of disability produced by such infections in newborns, which includes neurodevelopmental sequelae and sensorineural hearing loss (SNHL), has increased. Although much of the injury produced by infection in utero likely is irreversible, antiviral therapy of newborns with CMV infection is an option available to clinicians. Currently three antivirals are licensed for treatment of CMV: ganciclovir (and its prodrug, valganciclovir), foscarnet, and cidofovir. Novel antiviral therapies, which employ mechanisms of action that differ from these agents, also are in development. Experience with these agents in the setting of congenital and perinatal CMV infection is limited, but encouraging data come from a controlled clinical trial indicating that ganciclovir therapy may be of value in limiting the neurodevelopmental injury, particularly SNHL, caused by congenital infection. Newborn screening programs for CMV infection need to be developed and implemented. Infants with congenital CMV infection, once identified, could then be considered as candidates for antiviral therapy, and careful neurodevelopmental and hearing screening follow-up care plans could be established. CMV vaccines, once available, may ultimately be the best control strategy for this important public health problem.