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.

Cytomegalovirus variation among newborns treated with valganciclovir.

Congenital cytomegalovirus (cCMV) infection is the leading non-genetic cause of long-term neurological and sensory sequelae, the most common being sensorineural hearing loss (SNHL). Standard therapy for infants with symptomatic cCMV is valganciclovir for six months. However, little is known about the effects of antiviral therapy on CMV diversity while patients are on treatment. In this study, CMV variation was analyzed from urine specimens isolated from two patients with cCMV shortly after birth and at seven months. One was treated with valganciclovir for six weeks and the other for six months. In order to track these variants a novel bioinformatic approach was employed to analyze changes in low frequency variants over time. In the infant receiving antivirals for only six weeks, there was a fourfold increase in variation in UL97 from the seven month specimen. Furthermore, an eightfold increase in variation was seen in UL83 (pp65) with seven potential escape mutations occurring, and a twofold increase in UL73 (gN). In contrast variation did not increase or was reduced in these coding regions in the infant receiving valganciclovir for six months. However, there were increases in other CMV regions in samples isolated from both patients indicating further longitudinal studies are warranted to better understand the interplay between CMV diversity, antiviral therapy and patient outcome.

Clinical outcome and the role of antivirals in congenital cytomegalovirus infection.

Congenital cytomegalovirus (cCMV) infection is a leading cause of hearing loss and neurological disabilities in children worldwide. Although a minority of infants with cCMV will have symptoms at a birth, these children are at high risk of long-term sequelae. Most infants with cCMV have no clinical signs at birth (asymptomatic), but 10-15% will develop hearing loss. The diagnosis of cCMV relies on detection of the virus from urine or saliva within the first three weeks of life, with saliva PCR being the preferred method due to ease of collection and high sensitivity of the assay. Measures to prevent mother-to-child transmission of CMV are limited, and antiviral therapy with valganciclovir for 6 months is the standard of care for infants with symptomatic cCMV. As more infants with cCMV are being identified through newborn screening, studies are urgently needed to address antiviral treatment in asymptomatic infants and the implementation of prevention strategies to prevent fetal infection. This article is part of the symposium "New drugs and vaccines for DNA virus infections: a symposium in memory of Mark Prichard."

Congenital Cytomegalovirus Infection.

Congenital cytomegalovirus (cCMV) infection is a leading cause of hearing loss and neurological disabilities in children, with the disease burden and disabilities due to cCMV greater than many other well recognized childhood conditions. A minority of infants with cCMV will have symptoms at birth. Infants with symptomatic cCMV are at higher risk for sequelae than those born without symptoms. The majority of infants with cCMV are asymptomatic at birth, but 10%-15% will develop hearing loss. Although clinical symptoms can help predict which infants will have sensorineural hearing loss, among asymptomatic cCMV there are currently no predictors of adverse outcome. The identification of a biomarker to identify those at highest risk of sequelae is highly desirable to target interventions to those who could potentially benefit. Because there is increasing rationale for establishing both targeted and universal screening programs for cCMV in the United States and worldwide, this is an urgent priority.

Correction to: Association of CMV genomic mutations with symptomatic infection and hearing loss in congenital CMV infection.

After publication of the original article [1], we were notified that Fig. 3 has "Fig. 1" posted on the top of it and Figs. 4 and 5 have "Genomic Position" in a different spot.

Cytomegalovirus Genetic Diversity Following Primary Infection.

BACKGROUND: Infection with multiple cytomegalovirus (CMV) strains (mixed infection) was reported in a variety of hosts. As the virus genetic diversity in primary CMV infection and the changes over time remain incompletely defined, we examined CMV diversity and changes in diversity over time in healthy adolescent females who participated in a phase 2 CMV gB/MF59 vaccine trial. METHODS: CMV genetic diversity was determined by genotyping of 5 genes-gB (UL55), gH (UL75), gN (UL73), US28, and UL144-in urine, saliva, and plasma samples from 15 study subjects. RESULTS: At the time of primary infection, 5 of 12 (42%) urine samples had multiple virus strains, and 50% of vaccine recipients were infected with gB1 genotype (vaccine strain). Mixed infection was documented in all 15 subjects within 3 months after primary infection, and the majority had different CMV genotypes in different compartments. Changes in genotypes over time were observed in all subjects. CONCLUSIONS: Infection with multiple CMV genotypes was common during primary infection and further diversification occurred over time. Infection with gB1 genotype in vaccine recipients suggests a lack of strain-specific protection from the vaccine. As only 5 polymorphic genes were assessed, this study likely underestimated the true genetic diversity in primary CMV infection.

Association of CMV genomic mutations with symptomatic infection and hearing loss in congenital CMV infection.

BACKGROUND: Congenital cytomegalovirus (cCMV) infection is the most common congenital infection and a leading cause of long-term neurological and sensory sequelae, the most common being sensorineural hearing loss (SNHL). Despite extensive research, clinical or laboratory markers to identify CMV infected children with increased risk for disease have not been identified. This study utilizes viral whole-genome next generation-sequencing (NGS) of specimens from congenitally infected infants to explore viral diversity and specific viral variants that may be associated with symptomatic infection and SNHL. METHODS: CMV DNA from urine specimens of 30 infants (17 asymptomatic, 13 symptomatic) was target enriched and next generation sequenced resulting in 93% coverage of the CMV genome allowing analysis of viral diversity. RESULTS: Variant frequency distribution was compared between children with symptomatic and asymptomatic cCMV and those with (n = 13) and without (n = 17) hearing loss. The CMV genes UL48A, UL88, US19 and US22 were found to have an increase in nucleotide diversity in symptomatic children; while UL57, UL20, UL104, US14, UL115, and UL35 had an increase in diversity in children with hearing loss. An analysis of single variant differences between symptomatic and asymptomatic children found UL55 to have the highest number, while the most variants associated with SNHL were in the RL11 gene family. In asymptomatic infants with SNHL, mutations were observed more frequently in UL33 and UL20. CONCLUSION: CMV genomes from infected newborns can be mapped to 93% of the genome at a depth allowing accurate and reproducible analysis of polymorphisms for variant and gene discovery that may be linked to symptomatic and hearing loss outcomes.

Racial and Ethnic Differences in the Prevalence of Congenital Cytomegalovirus Infection.

OBJECTIVE: To evaluate the impact of race and ethnicity upon the prevalence and clinical spectrum of congenital cytomegalovirus infection (cCMV). STUDY DESIGN: From 2007 to 2012, 100 332 infants from 7 medical centers were screened for cCMV while in the hospital. Ethnicity and race were collected and cCMV prevalence rates were calculated. RESULTS: The overall prevalence of cCMV in the cohort was 4.5 per 1000 live births (95% CI, 4.1-4.9). Black infants had the highest cCMV prevalence (9.5 per 1000 live births; 95% CI, 8.3-11.0), followed by multiracial infants (7.8 per 1000 live births; 95% CI, 4.7-12.0). Significantly lower prevalence rates were observed in non-Hispanic white infants (2.7 per 1000 live births; 95% CI, 2.2-3.3), Hispanic white infants (3.0 per 1000 live births; 95% CI, 2.4-3.6), and Asian infants (1.0 per 1000 live births; 95% CI, 0.3-2.5). After adjusting for socioeconomic status and maternal age, black infants were significantly more likely to have cCMV compared with non-Hispanic white infants (adjusted prevalence OR, 1.9; 95% CI, 1.4-2.5). Hispanic white infants had a slightly lower risk of having cCMV compared with non-Hispanic white infants (adjusted prevalence OR, 0.7; 95% CI, 0.5-1.0). However, no significant differences in symptomatic cCMV (9.6%) and sensorineural hearing loss (7.8%) were observed between the race/ethnic groups. CONCLUSIONS: Significant racial and ethnic differences exist in the prevalence of cCMV, even after adjusting for socioeconomic status and maternal age. Although once infected, the newborn disease and rates of hearing loss in infants are similar with respect to race and ethnicity.

Contribution of Breastfeeding to False-Positive Saliva Polymerase Chain Reaction for Newborn Congenital Cytomegalovirus Screening.

Real-time polymerase chain reaction (PCR) of saliva is highly sensitive for newborn congenital cytomegalovirus (CMV) screening. This study uses nationally published CMV seroprevalence and breastfeeding rates to estimate the contribution of CMV DNA in breast milk to false-positive saliva PCR results. The false-positive rates adjusted for breastfeeding ranged from 0.03% in white Hispanic persons to 0.14% in white non-Hispanic persons. Saliva CMV PCR for newborn screening is highly sensitive, and the low false-positive rates in this study suggest that saliva PCR results are unlikely to be significantly influenced by breastfeeding or other perinatal exposures.

Pathogenesis of Non-Zika Congenital Viral Infections.

A widespread epidemic of Zika virus (ZIKV) infection was reported in 2015 from South and Central America and the Caribbean. Although the full spectrum of ZIKV infection of the newborn has yet to be determined, other maternal viral infections resulting in transmission to the fetus provide instructive lessons that can be applied to the prospective evaluation of individuals with ZIKV infection. This review focuses on those other congenital infections, including rubella, congenital cytomegalovirus, human immunodeficiency virus, hepatitis B virus, and neonatal herpes simplex virus, from which lessons for the evaluation of ZIKV in the newborn can be applied.

Breast Milk Human Cytomegalovirus (CMV) Viral Load and the Establishment of Breast Milk CMV-pp65-Specific CD8 T Cells in Human CMV Infected Mothers.

The role of human cytomegalovirus (HCMV)-specific T-cell responses in breast milk of HCMV-seropositive mothers is not well defined. In these studies, we demonstrate that the frequency of cytomegalovirus (CMV)-pp65-specific T-cell responses in peripheral blood mononuclear cells (PBMCs) and breast milk cells (BMCs) is increased for CD8+ T cells in both sample sources when compared with CD4+ T cells. The frequency of pp55-specific CD8 T cells producing interferon γ (IFN-γ) alone or dual IFN-γ/granzyme rB producers is increased in breast milk compared with PBMCs. Lastly, we observed a positive correlation between breast milk viral load and the CD8 pp65-specific response, suggesting that local virus replication drives antigen-specific CD8 T cells into the breast.

Newborn Dried Blood Spot Polymerase Chain Reaction to Identify Infants with Congenital Cytomegalovirus-Associated Sensorineural Hearing Loss.

OBJECTIVE: To determine the utility of dried blood spot (DBS) polymerase chain reaction (PCR) in identifying infants with cytomegalovirus (CMV) infection-associated sensorineural hearing loss (SNHL). STUDY DESIGN: Newborns at 7 US hospitals between March 2007 and March 2012 were screened for CMV by saliva rapid culture and/or PCR. Infected infants were monitored for SNHL during the first 4 years of life to determine sensitivity, specificity, and positive and negative likelihood ratios of DBS PCR for identifying CMV-associated SNHL. RESULTS: DBS at birth was positive in 11 of 26 children (42%) with SNHL at age 4 years and in 72 of 270 children (27%) with normal hearing (P = .11). The sensitivity (42.3%; 95% CI, 23.4%-63.1%) and specificity (73.3%; 95% CI, 67.6%-78.5%) was low for DBS PCR in identifying children with SNHL at age 4 years. The positive and negative likelihood ratios of DBS PCR positivity to detect CMV-associated SNHL at age 4 years were 1.6 (95% CI, 0.97-2.6) and 0.8 (95% CI, 0.6-1.1), respectively. There was no difference in DBS viral loads between children with SNHL and those without SNHL. CONCLUSIONS: DBS PCR for CMV has low sensitivity and specificity for identifying infants with CMV-associated hearing loss. These findings, together with previous reports, demonstrate that DBS PCR does not identify either the majority of CMV-infected newborns or those with CMV-associated SNHL early in life.

Clinical Predictors of Sensorineural Hearing Loss and Cognitive Outcome in Infants with Symptomatic Congenital Cytomegalovirus Infection.

The objective of this study was to determine newborn clinical findings predictive of adverse clinical outcomes in infants with symptomatic congenital cytomegalovirus infection. Of 160 infants, significantly more children with central nervous system involvement had sensorineural hearing loss (P = 0.0007) and an IQ ≤70 (P < 0.0001) compared with infants with transient findings or only a petechial rash.

Chromobacterium Violaceum Sepsis: Rethinking Conventional Therapy to Improve Outcome.

BACKGROUND: Chromobacterium violaceum (C. violaceum) is a facultative anaerobic gram-negative bacterium found in soil and water, especially in tropical and subtropical areas. Although infection in humans is rare, it is associated with significant morbidity. The bacterium is known for its resistance to multiple antimicrobials, and the possibility of relapse and reinfection. Presence of bacteremia, disseminated infection, and ineffective antimicrobial agents are predictors of mortality. CASE REPORT: We report the case of a previously healthy 11-year-old male with C. violaceum sepsis who was exposed to stagnant water. He presented with severe septic shock and developed multi-organ system failure. Initial presumptive diagnosis was staphylococcal infection secondary to presence of skin abscesses resulting in antibiotic coverage with vancomycin, clindamycin, nafcillin and ceftriaxone. He also had multiple lung and liver abscesses. Once C. violaceum was identified, he received meropenem and ciprofloxacin, and was later discharged on ertapenem and trimethoprim-sulfamethoxazole (TMP-SMX) to complete a total of six months of antibiotics. He was diagnosed with chronic granulomatous disease (CGD) and is currently on prophylactic TMP-SMX and itraconazole. He has not had any relapses since his initial presentation. CONCLUSIONS: This case highlights the importance of considering C. violaceum as a relevant human pathogen, and considering it early in temperate regions, particularly in cases of fulminant sepsis associated with multi-organ abscesses. Once C. violaceum is identified, appropriate antimicrobial therapy should be started promptly, and sufficient duration of treatment is necessary for successful therapy.

Urine Collection Method for the Diagnosis of Congenital Cytomegalovirus Infection.

Congenital cytomegalovirus infection is traditionally diagnosed by virus detection in saliva or urine. Virus culture was positive in significantly fewer urine samples collected using cotton balls in diapers (55.2%) than with samples collected by bags (93.2%) from newborns screened positive for CMV in saliva. However, polymerase chain reaction was positive in 95% of urine samples regardless of the collection method.

Comparison of saliva PCR assay versus rapid culture for detection of congenital cytomegalovirus infection.

As part of the CMV and Hearing Multicenter Screening (CHIMES) study, 72,239 newborns were screened for cytomegalovirus by rapid culture and real-time PCR of saliva samples. Of the 266 infants with congenital cytomegalovirus infection, discordance between rapid culture and PCR was observed in 14 children, and 13 were identified only by PCR, demonstrating the superiority of the PCR assay.

Detection of congenital cytomegalovirus infection by real-time polymerase chain reaction analysis of saliva or urine specimens.

Viral culture of urine or saliva has been the gold standard technique for the diagnosis of congenital cytomegalovirus (CMV) infection. Results of rapid culture and polymerase chain reaction (PCR) analysis of urine and saliva specimens from 80 children were compared to determine the clinical utility of a real-time PCR assay for diagnosis of congenital CMV infection. Results of urine PCR were positive in 98.8% of specimens. Three PCR-positive urine samples were culture negative. Results of saliva PCR and culture were concordant in 78 specimens (97.5%). Two PCR-positive saliva samples were culture negative. These findings demonstrate that PCR performs as well as rapid culture of urine or saliva specimens for diagnosing congenital CMV infection and saliva specimens are easier to collect. Because PCR also offers more rapid turnaround, is unlikely to be affected by storage and transport conditions, has lower cost, and may be adapted to high-throughput situations, it is well suited for targeted testing and large-scale screening for CMV.

Spectrum of disease and outcome in children with symptomatic congenital cytomegalovirus infection.

OBJECTIVE: To evaluate differences in presentation and outcomes in children with symptomatic congenital cytomegalovirus (cCMV) identified on newborn screening (screened group) and those identified based on clinical findings at birth (referred group). STUDY DESIGN: Data on 178 infants with symptomatic cCMV were analyzed. Demographic characteristics, clinical and laboratory findings documented in the nursery, and sequelae data were compared between the screened and the referred groups using χ(2) or Fisher exact test. RESULTS: Two or more clinical findings were detected at birth in 91% of referred infants, and only 58% of screened infants (P < .001). Significantly more children in the referred group had hearing loss compared with screened infants (P = .009). Fifty-one percent of screened children were free of sequelae compared with only 28% of the referred group (P < .003). CONCLUSIONS: Infants with symptomatic cCMV identified based on clinical suspicion have more severe disease at birth and more commonly have sequelae than those identified on newborn screening. Inclusion of referral infants in many previous reports may have overestimated the severity of disease because of selection bias. Defining the complete spectrum of symptomatic disease due to cCMV and providing precise estimates of disease burden can only be gathered from large newborn screening studies.