Economic assessments of the burden of congenital cytomegalovirus infection and the cost-effectiveness of prevention strategies

Autism Spectrum Disorder Diagnoses and Congenital Cytomegalovirus

OBJECTIVE

To examine the association between congenital cytomegalovirus (cCMV) and autism spectrum disorder (ASD) administrative diagnoses in US children.

METHODS

Cohort study using 2014 to 2020 Medicaid claims data. We used diagnosis codes to identify cCMV (exposure), ASD (outcome), and covariates among children enrolled from birth through ≥4 to <7 years. Covariates include central nervous system (CNS) anomaly or injury diagnosis codes, including brain anomaly, microcephaly within 45 days of birth, cerebral palsy, epilepsy, or chorioretinitis. We used Cox proportional hazards regression models to estimate hazard ratios and 95% confidence intervals, overall and stratified by sex, birth weight and gestational age outcome (low birth weight or preterm birth), and presence of CNS anomaly or injury.

RESULTS

Among 2 989 659 children, we identified 1044 (3.5 per 10 000) children with cCMV and 74 872 (25.0 per 1000) children with ASD. Of those with cCMV, 49% also had CNS anomaly or injury diagnosis codes. Children with cCMV were more likely to have ASD diagnoses (hazard ratio: 2.5; 95% confidence interval: 2.0-3.2, adjusting for birth year, sex, and region). This association differed by sex and absence of CNS anomaly or injury but not birth outcome.

CONCLUSIONS

Children with (versus without) cCMV diagnoses in Medicaid claims data, most of whom likely had symptomatic cCMV, were more likely to have ASD diagnoses. Future research investigating ASD risk among cohorts identified through universal cCMV screening may help elucidate these observed associations.

Estimates of congenital cytomegalovirus-attributable infant mortality in high-income countries: A review

As many as 5%-10% of infants with symptomatic congenital cytomegalovirus (cCMV) disease, or 0.4%-0.8% of all liveborn infants with cCMV infection, die in early infancy in high-income countries. However, estimates are uncertain due to several potential biases that can result from data limitations and study designs. First, infants with cCMV infections who die prior to diagnosis, which usually occurs at 1-4 weeks after birth, may be excluded from both the count of deaths and the denominator of cCMV births, resulting in left truncation and immortal time biases. These 'biases' are features of the data and do not reflect bias on the part of researchers, but understanding the potential existence of threats to validity can help with interpretation of findings. Left truncation of infant deaths occurring prior to diagnosis of cCMV can result in understatement of the burden of infant deaths due to cCMV. Conversely, overestimation of infant deaths associated with symptomatic cCMV may occur in clinical case series owing to greater representation of relatively severely affected infants owing to ascertainment and referral biases. In this review, we summarise the characteristics of 26 studies that reported estimates of cCMV-associated infant deaths, including potential biases or limitations to which those estimates may have been subject. We discuss study designs whose implementation might generate improved estimates of infant deaths attributable to cCMV. More complete estimates of the overall public health impact of cCMV could inform current and future screening, prevention, and vaccine research.

Neurodevelopmental outcomes of children with congenital cytomegalovirus: a systematic scoping review

BACKGROUND

With the emergence of newborn congenital cytomegalovirus (cCMV) screening programs, more infants are being diagnosed and require long-term follow-up. The objective of the study was to summarize the literature to date on neurodevelopmental outcomes in children with cCMV with attention to study-specific definitions of disease severity (symptomatic vs. asymptomatic).

METHODS

This systematic scoping review included studies of children with cCMV (≤18 years-old) measuring neurodevelopment in ≥1 domain: global, gross motor, fine motor, speech/language, and intellectual/cognitive. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. PubMed, PsychInfo, and Embase databases were searched.

RESULTS

33 studies met inclusion criteria. Global development most frequently measured (n = 21), followed by cognitive/intellectual (n = 16) and speech/language (n = 8). Most (31/33) studies differentiated children by cCMV severity (symptomatic vs. asymptomatic), definitions of which ranged broadly. 15/21 studies described global development categorically (e.g., normal vs. abnormal). Across studies and domains, children with cCMV generally had equivalent or lower scores (vs. controls or normed measures).

CONCLUSIONS

Variation in definitions of cCMV severity and blunt categorical outcomes may limit the generalizability of findings. Future studies should utilize standardized definitions of disease severity and in-depth measurement and reporting of neurodevelopmental outcomes in children with cCMV.

IMPACT

Neurodevelopmental delays are common among children with cCMV, although gaps in the literature to have made quantification of such delays challenging. Variation in definitions of asymptomatic and symptomatic cCMV as well as the use of categorical outcomes of neurodevelopment (e.g., normal vs. abnormal) limits the generalizability and clinical utility of findings.

Decoding human cytomegalovirus for the development of innovative diagnostics to detect congenital infection

Cytomegalovirus is the most common cause of congenital infectious disease and the leading nongenetic etiology of sensorineural hearing loss. Although most infected neonates are asymptomatic at birth, congenital cytomegalovirus infection is responsible for nearly 400 infant deaths annually in the United States and may lead to significant long-term neurodevelopmental impairments in survivors. The resulting financial and social burdens of congenital cytomegalovirus infection have led many medical centers to initiate targeted testing after birth, with a growing advocacy to advance universal newborn screening. While no cures or vaccines are currently available to eliminate or prevent cytomegalovirus infection, much has been learned over the last five years regarding disease pathophysiology and viral replication cycles that may enable the development of innovative diagnostics and therapeutics. This Review will detail our current understanding of congenital cytomegalovirus infection, while focusing our discussion on routine and emerging diagnostics for viral detection, quantification, and long-term prognostication. IMPACT: This review highlights our current understanding of the fetal transmission of human cytomegalovirus. It details clinical signs and physical findings of congenital cytomegalovirus infection. This submission discusses currently available cytomegalovirus diagnostics and introduces emerging platforms that promise improved sensitivity, specificity, limit of detection, viral quantification, detection of genomic antiviral resistance, and infection staging (primary, latency, reactivation, reinfection).

Newborn cytomegalovirus screening: is this the new standard?

PURPOSE OF REVIEW

Congenital cytomegalovirus infection (cCMV) is a major cause of childhood hearing loss and neurodevelopmental delay. Early identification of cCMV allows for interventions that improve outcomes, particularly for cCMV-related hearing loss that develops in early childhood. Most cCMV is asymptomatic at birth and is rarely diagnosed without newborn screening. Therefore, various approaches to cCMV screening are increasingly being adopted.

RECENT FINDINGS

Both universal screening (testing all newborns) and targeted screening (testing triggered by failed hearing screening) for cCMV appear valuable, feasible and cost-effective, though universal screening is predicted to have greatest potential overall benefits. CMV PCR testing of newborn oral swabs is sensitive and practical and is therefore widely used in targeted screening programs. In contrast, PCR using dried-blood spots (DBS) is less sensitive but was adopted by current universal cCMV screening initiatives because DBS are already collected from all newborns in high-income countries, which circumvents large-scale oral swab collection.

SUMMARY

Targeted screening is widely recommended as standard of care, while universal screening is less common but is progressively considered as the optimal strategy for identification of children with cCMV. As with all screening programs, cCMV screening requires commitments to equitable and reliable testing, follow-up and services.

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.

Congenital cytomegalovirus infection: the state of the art and future perspectives

Congenital cytomegalovirus (cCMV) infection is the most common congenital infection, with an estimated incidence of approximately one in 200 infants in high-income settings. Approximately one in four children may experience life-long consequences, including sensorineural hearing loss and neurodisability. Knowledge regarding prevention, diagnosis, and treatment increased in the recent years, but some challenges remain. In this review, we tried to summarize the current knowledge on both the obstetrical and pediatric areas, while also highlighting controversial aspects and future perspectives. There is a need to enhance awareness among the general population and pregnant women through specific information programs. Further research is needed to better define the classification of individuals at birth and to have a deeper understanding of the long-term outcomes for so defined children. Finally, the availability of valaciclovir medication throughout pregnancy, where appropriate, has prompted the assessment of a universal serological antenatal screening. It is recommended to establish a dedicated unit for better evaluation and management of both mothers and children.

Vaccine value profile for cytomegalovirus

Cytomegalovirus (CMV) is the most common infectious cause of congenital malformation and a leading cause of developmental disabilities such as sensorineural hearing loss (SNHL), motor and cognitive deficits. The significant disease burden from congenital CMV infection (cCMV) led the US National Institute of Medicine to rank CMV vaccine development as the highest priority. An average of 6.7/1000 live births are affected by cCMV, but the prevalence varies across and within countries. In contrast to other congenital infections such as rubella and toxoplasmosis, the prevalence of cCMV increases with CMV seroprevalence rates in the population. The true global burden of cCMV disease is likely underestimated because most infected infants (85-90 %) have asymptomatic infection and are not identified. However, about 7-11 % of those with asymptomatic infection will develop SNHL throughout early childhood. Although no licensed CMV vaccine exists, several candidate vaccines are in development, including one currently in phase 3 trials. Licensure of one or more vaccine candidates is feasible within the next five years. Various models of CMV vaccine strategies employing different target populations have shown to provide substantial benefit in reducing cCMV. Although CMV can cause end-organ disease with significant morbidity and mortality in immunocompromised individuals, the focus of this vaccine value profile (VVP) is on preventing or reducing the cCMV disease burden. This CMV VVP provides a high-level, comprehensive assessment of the currently available data to inform the potential public health, economic, and societal value of CMV vaccines. The CMV VVP was developed by a working group of subject matter experts from academia, public health groups, policy organizations, and non-profit organizations. All contributors have extensive expertise on various elements of the CMV VVP and have described the state of knowledge and identified the current gaps. The VVP was developed using only existing and publicly available information.

Treatment with valacyclovir during pregnancy for prevention of congenital cytomegalovirus infection: a real-life multicenter Italian observational study

BACKGROUND

Valacyclovir is the only treatment demonstrated to be effective for the prevention of vertical transmission of cytomegalovirus within a clinical randomized, placebo-controlled trial and has been reimbursed by the Italian National Health System since December 2020.

OBJECTIVE

This study reported the results of a real-life Italian multicenter observational study on cytomegalovirus infection in pregnancy evaluating the effect of the introduction of valacyclovir in the clinical practice for the prevention of vertical transmission of cytomegalovirus.

STUDY DESIGN

The outcomes of women who received valacyclovir treatment and their fetuses or newborns were compared with those of a retrospective cohort observed between 2010 and 2020 who did not receive the antiviral treatment. The inclusion criterion was the diagnosis of cytomegalovirus primary infection occurring in the periconceptional period or up to 24 weeks of gestation. The primary outcome was the transmission by the time of amniocentesis. The secondary outcomes were termination of pregnancy, transmission at birth, symptomatic infection at birth, and a composite outcome (termination of pregnancy or transmission at birth).

RESULTS

A total of 447 pregnant women from 10 centers were enrolled, 205 women treated with valacyclovir (called the valacyclovir group, including 1 twin pregnancy) and 242 women not treated with valacyclovir (called the no-valacyclovir group, including 2 twin pregnancies). Valacyclovir treatment was significantly associated with a reduction of the diagnosis of congenital cytomegalovirus infection by the time of amniocentesis (weighted odds ratio, 0.39; 90% confidence interval, 0.22-0.68; P=.005; relative reduction of 61%), termination of pregnancy (weighted odds ratio, 0.36; 90% confidence interval, 0.17-0.75; P=.0021; relative reduction of 64%), symptomatic congenital cytomegalovirus infection at birth (weighted odds ratio, 0.17; 90% confidence interval, 0.06-0.49; P=.006; relative reduction of 83%). The treatment had no significant effect on the rate of diagnosis of congenital cytomegalovirus infection at birth (weighted odds ratio, 0.85; 90% confidence interval, 0.57-1.26; P=.500), but the composite outcome (termination of pregnancy or diagnosis of congenital cytomegalovirus infection at birth) occurred more frequently in the no-valacyclovir group (weighted odds ratio, 0.62; 90% confidence interval, 0.44-0.88; P=.024). Of note, the only symptomatic newborns with congenital cytomegalovirus infection in the valacyclovir group (n=3) were among those with positive amniocentesis. Moreover, 19 women (9.3%) reported an adverse reaction to valacyclovir treatment, classified as mild in 17 cases and moderate in 2 cases. Lastly, 4 women (1.9%) presented renal toxicity with a slight increase in creatinine level, which was reversible after treatment suspension.

CONCLUSION

Our real-life data confirm that valacyclovir significantly reduces the rate of congenital cytomegalovirus diagnosis at the time of amniocentesis with a good tolerability profile and show that the treatment is associated with a reduction of termination of pregnancy and symptomatic congenital cytomegalovirus infection at birth.

Neurodevelopmental outcomes in congenital and perinatal infections

PURPOSE OF REVIEW

Congenital infections are a major cause of childhood multidomain neurodevelopmental disabilities. They contribute to a range of structural brain abnormalities that can cause severe neurodevelopmental impairment, cerebral palsy, epilepsy, and neurosensory impairments. New congenital infections and global viral pandemics have emerged, with some affecting the developing brain and causing neurodevelopmental concerns. This review aims to provide current understanding of fetal infections and their impact on neurodevelopment.

RECENT FINDINGS

There are a growing list of congenital infections causing neurodevelopmental issues, including cytomegalovirus, Zika virus, syphilis, rubella, lymphocytic choriomeningitis virus, and toxoplasmosis. Fetal exposure to maternal SARS-CoV-2 may also pose risk to the developing brain and impact neurodevelopmental outcomes, although studies have conflicting results. As Zika virus was a recently identified congenital infection, there are several new reports on child neurodevelopment in the Caribbean and Central and South America. For many congenital infections, children with in-utero exposure, even if asymptomatic at birth, may have neurodevelopmental concerns manifest over time.

SUMMARY

Congenital infections should be considered in the differential diagnosis of a child with neurodevelopmental impairments. Detailed pregnancy history, exposure risk, and testing should guide diagnosis and multidisciplinary evaluation. Children with congenital infections should have long-term follow-up to assess for neurodevelopmental delays and other neurosensory impairments. Children with confirmed delays or high-risk should be referred for rehabilitation therapies.

A systematic literature review of the economic and healthcare resource burden of cytomegalovirus

OBJECTIVE

Cytomegalovirus (CMV) can infect individuals at any age, including infants, who may contract it from infected mothers (congenital CMV [cCMV]). Whereas CMV infection is typically asymptomatic or causes mild illness in healthy individuals, infection can result in severe outcomes in immunocompromised individuals and in infants with cCMV. This systematic review aims to characterize the economic impact of CMV and cCMV infections.

METHODS

Medline, Embase, and LILACS databases were searched for publications reporting the economic impact of cCMV and CMV infections across all age groups. Manuscripts published between 2010 and 2020 from Australia, Latin America, Canada, Europe, Israel, Japan, the United States, and global (international, worldwide) studies were included; congress materials were excluded. Outcomes of interest included cCMV- and CMV-attributable direct costs/charges, resource utilization, and indirect/societal costs.

RESULTS

Of 751 records identified, 518 were excluded based on duplication, population, outcome, study design, or country. Overall, 55 articles were eligible for full-text review; 25 were further excluded due to population, outcome, study design, or congress abstract. Two publications were additionally identified, resulting in economic impact data compiled from 32 publications. Of these, 24 publications reported cost studies of cCMV or CMV, including evaluation of direct costs/charges, healthcare resource utilization, and indirect/societal costs, and 7 publications reported economic evaluations of interventions. The populations, methods and outcomes used across these studies varied widely.

CONCLUSIONS

CMV and cCMV infections impose a considerable economic impact on different countries, populations, and outcomes. There are substantial evidence gaps where further research is warranted.

The Prevalence of Symptomatic Congenital Cytomegalovirus Disease in Korea; A 15-Year Multicenter Study and Analysis of Big Data From National Health Insurance System

The birth prevalence of symptomatic congenital cytomegalovirus (cCMV) disease among live birth in Korea from a multicenter study was 0.06% during 2001-2015 with increasing frequency. The administrative prevalence of cCMV infection by big-data analysis from the national health insurance system was 0.01% and the average healthcare cost was US$2010 per person.

Healthcare costs of congenital cytomegalovirus (cCMV) disease in infants during the first two years of life: a retrospective German claims database analysis

BACKGROUND

Congenital cytomegalovirus (cCMV) infection can cause severe neurological damage, growth retardation, hearing loss, and microcephaly in infants. We aimed at assessing healthcare costs of infants with recorded cCMV diagnosis in an administrative claims database in the first 2 years of life.

METHODS

We conducted a retrospective, controlled cohort study using German claims data from the Institute for Applied Health Research Berlin (InGef) database. Incremental healthcare costs during the first and second year of life were assessed by matching (1:60) infants with cCMV diagnoses ≤ 90 days after birth (cCMV₉₀ cohort) to infants without cCMV diagnosis ("representative" controls) and infants with cCMV diagnoses ≤ 21 days after birth plus specific symptoms (cCMV_21-S) to infants without cCMV and any ICD-10-GM records (besides Z00-Z99) until 4^th preventive health check-up ("healthy" controls). Due to missing data, mean imputation was applied for aids and remedies costs.

RESULTS

We identified 54 and 24 infants born 2014-2018 for the cCMV₉₀ and cCMV_21-S cohorts, respectively. During the first year, mean (median) healthcare costs were significantly higher in cCMV₉₀ cases vs. "representative" controls (€22,737 (€9759) vs. €3091 (€863), p < 0.001), with 87.2% inpatient costs. Healthcare costs for cCMV_21-S cases compared to "healthy" controls were €34,498 (€20,924) vs. €680 (€569), p < 0.001. Differences decreased for both comparisons in the second year but remained statistically significant.

CONCLUSIONS

cCMV comprises a considerable economic burden for the German healthcare system (€19,646 to €33,818 higher mean costs for infants with recorded cCMV diagnosis in the first year of life). Attempts should be made to reduce this burden.

Investigating N-arylpyrimidinamine (NAPA) compounds as early-stage inhibitors against human cytomegalovirus

Human cytomegalovirus (CMV) is a ubiquitous β-herpesvirus that establishes latent asymptomatic infections in healthy individuals but can cause serious infections in immunocompromised people, resulting in increased risk of morbidity and mortality. The current FDA-approved CMV drugs target late stages of the CMV life-cycle. While these drugs are effective in most cases, they have serious drawbacks, including poor oral bioavailability, dose-limiting toxicity, and a low barrier to resistance. Given the clinical relevance of CMV-associated diseases, novel therapies are needed. Thus, a novel class of compounds that inhibits the early stages of the CMV life-cycle was identified and found to block infection of different strains in physiologically relevant cell types. This class of compounds, N-arylpyrimidinamine (NAPA), demonstrated potent anti-CMV activity against ganciclovir-sensitive and -resistant strains in in vitro replication assays, a selectivity index >30, and favorable in vitro ADME properties. Mechanism of action studies demonstrated that NAPA compounds inhibit an early step of virus infection. NAPA compounds are specific inhibitors of cytomegaloviruses and exhibited limited anti-viral activity against other herpesviruses. Collectively, we have identified a novel class of CMV inhibitor that effectively limits viral infection and proliferation.

Cross-sectional study to assess awareness of cytomegalovirus infection among pregnant women in Germany

BACKGROUND

Study aimed to assess awareness of congenital cytomegalovirus (CMV) infection and its determinants in pregnancy.

METHODS

Cross-sectional survey was conducted in five hospital-based maternity units in Germany. Pregnant women attending the maternity departments completed interviewer/self-administered survey questionnaire. High-risk group was defined according to contact with children under five years of age (at home or at work). Quantitative analyses using multivariable logistic regression were performed.

RESULTS

One thousand two hundred thirty-three pregnant women were included. 48.5% (n = 598) of women reported any knowledge about risk of CMV infection during pregnancy. CMV infection was less known than other infections or diseases (education about toxoplasmosis 95.5% (n = 1,177), listeriosis 60.5% (n = 746). 38% (n = 468) of participants received education about CMV. CMV awareness was associated with the level of education and employment in childcare or medical care. Only 32% (n = 394) of the women made use of serological screening for CMV during pregnancy (individual health service). 40.8% (n = 503) of pregnant women were classified as high-risk group. They had significantly higher knowledge and education about CMV, and msignificantlycant more often use of the serological screening.

CONCLUSIONS

Less than half of pregnant women surveyed were aware of potential risk associated with CMV infection during pregnancy. In our study,one-third third of pregnant women made use of the serological screening for CMV. Regarding the lack of current consensus on the role of serological CMV screening for pregnant women, hygiene preventive measures are the only evidence-based recommendation for pregnant women and knowledge increase could potentially have major public health impact.

Targeted screening for congenital cytomegalovirus infection: clinical, audiological and neuroimaging findings

OBJECTIVE

To evaluate clinical, audiological and neuroimaging findings in a cohort of infants diagnosed with congenital cytomegalovirus (cCMV) infection after failure at newborn hearing screening.

METHODS

A prospective observational study in the Netherlands, using the existing newborn hearing screening infrastructure for well babies. Between July 2012 and November 2016, cytomegalovirus (CMV) PCR testing of neonatally obtained dried blood spots (DBS) was offered to all infants who failed newborn hearing screening. Clinical, neuroimaging and audiological data were collected.

RESULTS

DBS of 1374 infants were successfully tested and 59 were positive for CMV (4.3%). Data of 54 infants were retrieved. Three were small for gestational age and six had microcephaly. Forty-eight (89%) had sensorineural hearing loss (SNHL), of whom half had unilateral SNHL. In both unilaterally and bilaterally affected children, the majority of the impaired ears had severe or profound hearing loss. Neuroimaging abnormalities were found in 40 of 48 (83%) children who had evaluable cranial ultrasound and/or cerebral MRI. The abnormalities were mild in 34, moderate in 3 and severe in 3 infants. The degree of SNHL and the severity of neuroimaging abnormalities were found to be correlated (p=0.002).

CONCLUSIONS

The yield of targeted cCMV screening following newborn hearing screening failure was eight times higher than the estimated national birth prevalence of cCMV. The majority of this cohort of infants with clinically unsuspected cCMV disease had confirmed SNHL, neuroimaging abnormalities and lower than average birth weights and head circumferences. Newborns who fail newborn hearing screening should be tested for CMV to ensure appropriate clinical, neurodevelopmental and audiological follow-up.

Congenital Cytomegalovirus Screening in Massachusetts Birth Hospitals: A Statewide Survey

This study sought to assess the current state of screening for congenital cytomegalovirus infection in newborns among birth hospitals and newborn nurseries in the state of Massachusetts. A survey assessing hospital protocols for cytomegalovirus testing in newborns was distributed to all birth hospitals and newborn nurseries in Massachusetts from November 2020 to February 2021. 73.3% of hospitals responded to at least one survey question. Of these, fewer than half (48.5%) had any established approach for neonatal cytomegalovirus screening. Salivary polymerase chain reaction was the most common testing modality. Most hospitals did not perform confirmatory testing for positive test results. Most respondents (87.9%) did not know or did not answer how results of cCMV screening were reported to families and who was responsible for coordinating care for cCMV-infected infants. We conclude that congenital cytomegalovirus screening protocols are absent or incomplete in most Massachusetts birth hospitals and newborn nurseries. A cohesive strategy involving standardized education and screening guidelines is needed to reduce the incidence and burden of congenital cytomegalovirus disease on children and their families.

Inconsistent Provider Testing Practices for Congenital Cytomegalovirus: Missed Diagnoses and Missed Opportunities

Newborn congenital cytomegalovirus (cCMV) screening programs have been found to increase the rates of early diagnosis and treatment. In North America, newborn cCMV screening programs have not been widely implemented, leaving healthcare providers to rely on clinical suspicion alone to prompt testing. This study sought to examine healthcare providers' cCMV testing practices at a quaternary children's hospital. A retrospective review of the electronic health record was completed for eligible infants over a six-year period. Bivariate calculations and analyses were performed. Between 2014 and 2019, a total of 40,091 infants were cared for at the study institution, of which 178 were tested for cCMV and 10 infants were diagnosed with cCMV. Isolated small-for-gestational age was the most common indication (53/178) to prompt testing. Overall, the cCMV testing rate was 4.5 tests per 1000 infants, with a resulting diagnostic prevalence of 0.2 cases per 1000 infants, which is 15-fold lower than the expected prevalence. Providers relying on clinical suspicion alone are infrequently testing infants for cCMV, resulting in missed diagnoses and missed opportunities for treatment. Systematic cCMV screening practices may improve diagnosis, treatment, and childhood outcomes.

Emerging Concepts in Congenital Cytomegalovirus

Over a century of research has focused on improving our understanding of congenital cytomegalovirus (cCMV), yet it remains the most common congenital infection in the United States, affecting 3 to 6 per 1000 live born infants each year. Pregnancies affected by cCMV are at a heightened risk of spontaneous abortion and intrauterine fetal demise. Neonates born with cCMV are also at substantial risk for long-term neurodevelopmental sequelae and disability, including sensorineural hearing loss, even those born without clinically apparent disease. Considerable progress has been made in recent years in study of the epidemiology and transmission of cCMV, developing better diagnostic strategies, implementing newborn screening programs, improving therapeutics, and launching vaccine trials. In this article, we review recent developments in the understanding of the virology and immunobiology of cytomegalovirus. We further discuss how this knowledge informs our understanding of the pathophysiology of cCMV and directs strategies aimed at improving outcomes and quality of life for congenitally infected children. We also provide an update on the epidemiology of cCMV in the United States, evolving scientific understanding of maternal-fetal transmission, enhanced screening approaches, and recognition of neonatal and long-term sequelae. Finally, we review the current landscape of pediatric cCMV research and provide recommendations for novel and high-priority areas for future investigation.

Data-Related Challenges in Cost-Effectiveness Analyses of Vaccines

Cost-effectiveness analyses (CEAs) are often prepared to quantify the expected economic value of potential vaccination strategies. Estimated outcomes and costs of vaccination strategies depend on numerous data inputs or assumptions, including estimates of vaccine efficacy and disease incidence in the absence of vaccination. Limitations in epidemiologic data can meaningfully affect both CEA estimates and the interpretation of those results by groups involved in vaccination policy decisions. Developers of CEAs should be transparent with regard to the ambiguity and uncertainty associated with epidemiologic information that is incorporated into their models. We describe selected data-related challenges to conducting CEAs for vaccination strategies, including generalizability of estimates of vaccine effectiveness, duration and functional form of vaccine protection that can change over time, indirect (herd) protection, and serotype replacement. We illustrate how CEA estimates can be sensitive to variations in specific epidemiologic assumptions, with examples from CEAs conducted for the USA that assessed vaccinations against human papillomavirus and pneumococcal disease. These challenges are certainly not limited to these two case studies and may be relevant to other vaccines.

Health Care Resource Utilization and Economic Burden Associated With Congenital Cytomegalovirus Infection: A Longitudinal Analysis of Data From Clinical Practice at a Large Health Care Provider in Israel

PURPOSE

Congenital cytomegalovirus infection (cCMVi) is the leading cause of nonhereditary sensorineural hearing loss and can cause other long-term neurodevelopmental disabilities; however, data on the economic burden of cCMVi during early childhood are scarce. The primary objective of the study was to describe longitudinal patterns of health care resource utilization (HCRU) and direct medical costs among infants with cCMVi compared to infants unexposed to cCMVi.

METHODS

A retrospective cohort study was performed using data on infants born between 2013 and 2017, as captured in the database of Maccabi Healthcare Services, a 2.5 million-member health care organization in Israel. cCMVi cases were identified by physician diagnosis and/or dispensed valganciclovir within 90 days after birth. Infants born to mothers CMV-seronegative throughout pregnancy were selected for comparison (unexposed controls). Infants were retrospectively followed up through December 31, 2018, or 4 years of age (Y4). HCRU included physician visits, hospital admissions, audiology tests/procedures, imaging, and valganciclovir treatment. Direct medical costs, in US dollars per person per year (USD PPPY) were calculated from the health-system perspective. To compare costs of cCMVi cases and controls, direct medical costs were estimated using a generalized linear model with a log link function and γ distribution after adjustment for patient characteristics.

FINDINGS

A total of 351 cCMVi cases and 11,733 control infants with continuous follow-up during their first year of life (Y1) were included in the study. In Y1, cases were more likely to have a hospital admission (8.5% cases vs 4.5% control; P < 0.001) and higher numbers of pediatrician visits (median, 18 vs 15), audiology visits and tests, and cranial ultrasounds (all, P < 0.05). Longitudinally, incremental costs associated with cases were highest in Y1 (1686.7 USD PPPY; cost ratio = 2.6; P < 0.001) and remained elevated through Y4.

IMPLICATIONS

cCMVi was associated with substantial increases in HCRU and economic burden during early childhood, and particularly during the first year of life.

Delays in diagnosis and treatment initiation for congenital cytomegalovirus infection - Why we need universal screening

INTRODUCTION

Congenital cytomegalovirus (cCMV) is the leading cause of neurodevelopmental and hearing impairment from in-utero infection. Late diagnosis results in limited treatment options and may compromise long-term outcome.

METHODS

A retrospective audit of infants with cCMV referred to a Tertiary Pediatric Infectious Diseases center from 2012-2021. Data collected included timing of diagnostics, treatment initiation and reasons for delays.

RESULTS

90 infants with confirmed cCMV were included, 46/90 (51%) were symptomatic at birth. Most common reasons for diagnostics in asymptomatic infants were failed newborn hearing screening (17/44, 39%) and antenatal risk-factors (14/44, 32%). Median age at cCMV diagnosis was 3 (range 0-68) and 7 (0-515) days, with median referral age 10 (1-120) and 22 (2-760) days for symptomatic and asymptomatic infants respectively. There was a significant risk of delay in diagnosis (>21 days) for asymptomatic infants [RR 2.93 (1.15-7.45); p = 0.02]. Of asymptomatic infants who received treatment, 13/24 (54%) commenced it within 28 days of life, a significant delay in treatment compared to 30/36 (83%) symptomatic infants [RR 2.75 (1.18-6.43); p = 0.02]. The commonest reason for delayed treatment initiation was delayed first diagnostic test for both symptomatic 4/6 (67%) and asymptomatic infants 9/11 (82%).

CONCLUSIONS

Delays in diagnosis and treatment for cCMV are unacceptably frequent and significantly higher in asymptomatic infants. Our study highlights the need for increased awareness among healthcare professionals, reconsideration of age-targets for Newborn Hearing Screening, and research that addresses the barriers to implementation of universal screening, which would ultimately facilitate prompt diagnosis and management of all infants with cCMV.

Identification of congenital CMV cases in administrative databases and implications for monitoring prevalence, healthcare utilization, and costs

OBJECTIVE

To critically review researchers' use of diagnosis codes to identify congenital cytomegalovirus (cCMV) infection or disease in healthcare administrative databases. Understanding the limitations of cCMV ascertainment in those databases can inform cCMV surveillance and health services research.

METHODS

We identified published studies that used diagnosis codes for cCMV or CMV in hospital discharge or health insurance claims and encounters records for infants to assess prevalence, use of services, or healthcare costs. We reviewed estimates of prevalence and of charges, costs, or expenditures associated with cCMV diagnosis codes.

RESULTS

Five studies assessed hospitalizations with cCMV diagnosis codes recorded in hospital discharge databases, from the United States (n = 3), Australia (n = 1), and the United Kingdom (n = 1). Six other studies analyzed claims or encounters data from the United States (n = 5) or Japan (n = 1) to identify infants with cCMV codes. Prevalence estimates of recognized cCMV ranged from 0.6 to 3.8 per 10,000 infants. Economic analyses reported a wide range of per-hospitalization or per-infant cost estimates, which lacked standardization or comparability.

CONCLUSIONS

The administrative prevalence of cCMV cases reported in published analyses of administrative data from North America, Western Europe, Japan, and Australia (0.6-3.8 per 10,000 infants) is an order of magnitude lower than the estimates of the true birth prevalence of 3-7 per 1,000 newborns based on universal newborn screening pilot studies conducted in the same regions. Nonetheless, in the absence of systematic surveillance for cCMV, administrative data might be useful for assessing trends in testing and clinical diagnosis. To the extent that cCMV cases recorded in administrative databases are not representative of the full spectrum of cCMV infection or disease, per-child cost estimates generated from those data may not be generalizable. On the other hand, claims data may be useful for estimating patterns of healthcare use and expenditures associated with combinations of diagnoses for cCMV and known complications of cCMV.