HCMV trimer- and pentamer-specific antibodies synergize for virus neutralization but do not correlate with congenital transmission.

Human cytomegalovirus (HCMV) causes substantial disease in transplant patients and harms the development of the nervous system in babies infected in utero. Thus, there is a major focus on developing safe and effective HCMV vaccines. Evidence has been presented that a major target of neutralizing antibodies (NAbs) is the HCMV pentamer glycoprotein gH/gL/UL128-131. In some studies, most of the NAbs in animal or human sera were found to recognize the pentamer, which mediates HCMV entry into endothelial and epithelial cells. It was also reported that pentamer-specific antibodies correlate with protection against transmission from mothers to babies. One problem with the studies on pentamer-specific NAbs to date has been that the studies did not compare the pentamer to the other major form of gH/gL, the gH/gL/gO trimer, which is essential for entry into all cell types. Here, we demonstrate that both trimer and pentamer NAbs are frequently found in human transplant patients' and pregnant mothers' sera. Depletion of human sera with trimer caused reductions in NAbs similar to that observed following depletion with the pentamer. The trimer- and pentamer-specific antibodies acted in a synergistic fashion to neutralize HCMV and also to prevent virus cell-to-cell spread. Importantly, there was no correlation between the titers of trimer- and pentamer-specific NAbs and transmission of HCMV from mothers to babies. Therefore, both the trimer and pentamer are important targets of NAbs. Nevertheless, these antibodies do not protect against transmission of HCMV from mothers to babies.

Contribution of Congenital Cytomegalovirus Infection to Permanent Hearing Loss in a Highly Seropositive Population: The Brazilian Cytomegalovirus Hearing and Maternal Secondary Infection Study.

BACKGROUND: The exact contribution of congenital cytomegalovirus infection (cCMVI) to permanent hearing loss (HL) in highly seropositive populations is unknown. We determined the contribution of cCMVI to HL and estimated the effectiveness of newborn hearing screening (HS) in identifying neonates with CMV-related HL. METHODS: A total of 11 900 neonates born from a population with ≥97% maternal seroprevalence were screened for cCMVI and HL. cCMVI was confirmed by detection of CMV-DNA in saliva and urine at age <3 weeks. RESULTS: Overall, 68 (0.6%; 95% confidence interval [CI], 0.4-0.7) neonates were identified with cCMVI. Of the 91 (0.8%) newborns who failed the HS, 24 (26.4%) were confirmed with HL, including 7 (29.2%; 95% CI, 17.2-59.3) with cCMVI. Another newborn with cCMVI passed the HS but was confirmed with HL at age 21 days. Of the 62 neonates with cCMVI who underwent a complete hearing evaluation, 8 (12.9%; 95% CI, 6.7-23.4) had HL and most (7/8; 87.5%; 95% CI, 46.6-99.7) were identified by HS. The rate of CMV-related HL was 8 per 11 887 neonates (0.7 per 1000 live births). The prevalence ratio of HL among neonates with cCMVI compared to CMV-uninfected neonates was 89.5 (95% CI, 39.7-202.0). No late-onset cCMVI-related HL was detected during a median follow-up of 36 months. CONCLUSIONS: cCMVI is an important cause of HL in childhood in all settings. Integrating targeted cCMVI screening among neonates who fail a HS could be a reasonable, cost-effective strategy to identify newborns with early-onset cCMVI-related HL.

Seroconversion for Cytomegalovirus Infection During Pregnancy and Fetal Infection in a Highly Seropositive Population: "The BraCHS Study".

We determined the risk of seroconversion in seronegative pregnant women living in a high seroprevalence population. Cytomegalovirus (CMV)-immunoglobulin G reactivity was determined at the 1st trimester in all women and sequentially for seronegative women. A total of 1915 of 1952 (98.1%; 95% confidence interval [CI], 97.4%-98.7%) women were seropositive, and 36 (1.8%; 95% CI, 1.3%-2.6%) were seronegative. Five of the 36-seronegative women seroconverted for a cumulative rate of 13.9% (95% CI, 4.8%-30.6%). Congenital CMV infection was diagnosed in 1 of 36 infants (2.8%; 95% CI, 0.5%-63.9%) born to seronegative women compared with 8 of 1685 (0.5%; 95% CI, 0.2%-1.0%) infants born to seropositive mothers. Even with a high risk of primary infection in seronegative women, most CMV-infected infants were born to women with pre-existing seroimmunity.

Cytomegalovirus Shedding in Seropositive Pregnant Women From a High-Seroprevalence Population: The Brazilian Cytomegalovirus Hearing and Maternal Secondary Infection Study.

Background: Most congenital cytomegalovirus (CMV) infections in highly seropositive populations occur in infants born to women with preexisting CMV seroimmunity. Although essential for developing prevention strategies, CMV shedding patterns in pregnant women with nonprimary infections have not been characterized. We investigated correlates of CMV shedding in a cohort of seropositive pregnant women. Methods: In a prospective study, saliva, urine, vaginal swabs, and blood were collected from 120 CMV-seropositive women in the first, second, and third trimesters and 1 month postpartum. Specimens were tested for CMV DNA by polymerase chain reaction. We analyzed the contribution of the specific maternal characteristics to viral shedding. Results: CMV shedding was detected at least once in 42 (35%) women. Mothers living with or providing daily care to young children (3-6 years) were twice as likely to shed CMV at least once compared to women with less exposure to young children (58% vs 26%; adjusted relative risk [aRR], 2.21; 95% confidence interval [CI], 1.37-3.56). Living in crowded households (≥2 people per room) was associated with viral shedding (64% vs 31%; aRR, 1.99; 95% CI, 1.26-3.13). Sexual activity as indicated by the number of sexual partners per year or condom use was not found to be a correlate of viral shedding. Conclusions: CMV shedding is relatively frequent in seropositive pregnant women. The association between virus shedding and caring for young children as well as crowded living conditions may provide opportunities for increased exposures that could lead to CMV reinfections in seropositive women.

Limits and patterns of cytomegalovirus genomic diversity in humans.

Human cytomegalovirus (HCMV) exhibits surprisingly high genomic diversity during natural infection although little is known about the limits or patterns of HCMV diversity among humans. To address this deficiency, we analyzed genomic diversity among congenitally infected infants. We show that there is an upper limit to HCMV genomic diversity in these patient samples, with ∼ 25% of the genome being devoid of polymorphisms. These low diversity regions were distributed across 26 loci that were preferentially located in DNA-processing genes. Furthermore, by developing, to our knowledge, the first genome-wide mutation and recombination rate maps for HCMV, we show that genomic diversity is positively correlated with these two rates. In contrast, median levels of viral genomic diversity did not vary between putatively single or mixed strain infections. We also provide evidence that HCMV populations isolated from vascular compartments of hosts from different continents are genetically similar and that polymorphisms in glycoproteins and regulatory proteins are enriched in these viral populations. This analysis provides the most highly detailed map of HCMV genomic diversity in human hosts to date and informs our understanding of the distribution of HCMV genomic diversity within human hosts.

Congenital Zika Virus Infection Induces Severe Spinal Cord Injury.

We report 2 fatal cases of congenital Zika virus (ZIKV) infection. Brain anomalies, including atrophy of the cerebral cortex and brainstem, and cerebellar aplasia were observed. The spinal cord showed architectural distortion, severe neuronal loss, and microcalcifications. The ZIKV proteins and flavivirus-like particles were detected in cytoplasm of spinal neurons, and spinal cord samples were positive for ZIKV RNA.

Characterizing human cytomegalovirus reinfection in congenitally infected infants: an evolutionary perspective.

Given the strong selective pressures often faced by populations when colonizing a novel habitat, the level of variation present on which selection may act is an important indicator of adaptive potential. While often discussed in an ecological context, this notion is also highly relevant in our clinical understanding of viral infection, in which the novel habitat is a new host. Thus, quantifying the factors determining levels of variation is of considerable importance for the design of improved treatment strategies. Here, we focus on such a quantification of human cytomegalovirus (HCMV) - a virus which can be transmitted across the placenta, resulting in foetal infection that can potentially cause severe disease in multiple organs. Recent studies using genomewide sequencing data have demonstrated that viral populations in some congenitally infected infants diverge rapidly over time and between tissue compartments within individuals, while in other infants, the populations remain highly stable. Here, we investigate the underlying causes of these extreme differences in observed intrahost levels of variation by estimating the underlying demographic histories of infection. Importantly, reinfection (i.e. population admixture) appears to be an important, and previously unappreciated, player. We highlight illustrative examples likely to represent a single-population transmission from a mother during pregnancy and multiple-population transmissions during pregnancy and after birth.

Normocephalic Children Exposed to Maternal Zika Virus Infection Do Not Have a Higher Risk of Neurodevelopmental Abnormalities around 24 Months of Age than Unexposed Children: A Controlled Study.

Although very few controlled studies are available, in utero Zika virus (ZIKV)-exposed children are considered at risk for neurodevelopmental abnormalities. We aimed to identify whether there is an excess risk of abnormalities in non-microcephalic children born to mothers with confirmed ZIKV infection compared with ZIKV-unexposed children from the same population. In a cross-sectional study nested in two larger cohorts, we compared 324 ZIKV-exposed children with 984 unexposed controls. Outcomes were assessed using the Bayley Screening Test III applied around 24 months of age. Relative risks for classifying children as emergent or at-risk for neurodevelopmental delay in at least one of five domains were calculated, adjusting for covariates. In four of the five domains, few children were classified as emergent (4-12%) or at-risk (0.3-2.16%) but for the expressive communication domain it was higher for emergent (19.1-42.9%). ZIKV-exposed children were half as frequently classified as emergent, including after adjusting for covariates [RR = 0.52 (CI 95% 0.40; 0.66)]. However, no difference was detected in the at-risk category [RR = 0.83 (CI 95% 0.48; 1.44)]. Normocephalic children exposed to the Zika virus during pregnancy do not have a higher risk of being classified as at risk for neurodevelopmental abnormalities at two years of age.

Congenital ocular toxoplasmosis in consecutive siblings.

Toxoplasma gondii infection can cause ocular manifestations after acquired and congenital disease. We report two cases of symptomatic congenital toxoplasmosis with ocular involvement in non-twin siblings, with a 2-year interval between pregnancies. Vertical transmission of toxoplasmosis in successive pregnancies, which was once considered impossible, is now found to be plausible even in immunocompetent subjects.

Comprehensive evaluation of risk factors for neonatal hearing loss in a large Brazilian cohort.

OBJECTIVES: To determine the incidence and risk factors of hearing loss (HL) in Brazilian neonates. STUDY DESIGN: 11,900 neonates were screened for hearing and congenital CMV (cCMV). Low and high-risk babies who did not pass their hearing screening and infants with cCMV were scheduled for a diagnostic audiologic evaluation. RESULTS: The incidence of HL was 2 per 1000 live-born infants (95% CI: 1-3). HL was higher in high-risk neonates than in low risk babies (18.6 vs. 0.3/1000 live births, respectively). Among infants exposed to isolated risk factors, association of HL with craniofacial abnormalities/syndromes (RR = 24.47; 95% CI: 5.9-100.9) and cCMV (RR = 9.54; 95% CI: 3.3-27.7) were observed. HL was 20 to 100-fold more likely in neonates exposed to ototoxic drugs in combination with cCMV or craniofacial/congenital anomalies. CONCLUSIONS: Strategies for the prevention of cCMV and exposure to ototoxic drugs may decrease the incidence of HL in this population.

Birth prevalence and natural history of congenital cytomegalovirus infection in a highly seroimmune population.

BACKGROUND: The natural history of congenital cytomegalovirus (CMV) infection is scarcely known in populations with high maternal CMV seroprevalence. This study evaluated the birth prevalence, clinical findings at birth, and hearing outcome in CMV-infected children from such a population. METHODS: Consecutively born infants were screened for the presence of CMV in urine and/or saliva specimens during the first 2 weeks after birth. Neonatal clinical findings were recorded, and CMV-infected children were tested to document hearing function during follow-up. A subset of mothers of CMV-infected infants were prenatally tested for the presence of anti-CMV immunoglobulin G antibodies. RESULTS: Congenital CMV infection was confirmed in 87 (1.08%; 95% confidence interval [CI], 0.86%-1.33%) of 8047 infants. Seven infants (8.1%; 95% CI, 3.3%-15.9%) had at least 1 clinical finding suggestive of CMV infection, and 4 (4.6%; 95% CI, 1.3%-11.3%) had >3 findings of systemic disease. Sensorineural hearing loss was found in 5 (8.6%; 95% CI, 2.9%-19.0%) of 58 children tested at a median age of 21 months. Bilateral profound hearing loss was observed in 2 children, and the hearing threshold was >60 decibels in all 5 children with hearing loss, including 2 children born to mothers with probable nonprimary CMV infection. CONCLUSIONS: The results of this large newborn screening study in a population with high CMV seroimmunity provide additional evidence that congenital CMV disease occurs in populations with high seroprevalence rates, with a similar incidence of CMV-related hearing loss to that reported in the offspring of women from populations in developed countries with lower rates of seroimmunity to CMV.

High Levels of Chemokine C-C Motif Ligand 20 in Human Milk and Its Production by Oral Keratinocytes.

BACKGROUND: Chemokine C-C motif ligand 20 (CCL20) is implicated in the formation and function of mucosal lymphoid tissues. Although CCL20 is secreted by many normal human tissues, no studies have evaluated the presence of CCL20 in human milk or its production by oral keratinocytes stimulated by human milk. OBJECTIVE: To evaluate the presence of CCL20 in breast milk and verify CCL20 secretion in vitro by oral keratinocytes stimulated with human and bovine milk, as well as its possible association with breast milk lactoferrin levels. MATERIALS AND METHODS: The levels of CCL20 and lactoferrin were measured by enzyme-linked immunosorbent assay in human milk at three different stages of maturation from 74 healthy breastfeeding mothers. In vitro, oral keratinocytes were stimulated with human and bovine milk, and CCL20 was measured in their supernatant. RESULTS: High concentrations of CCL20 were detected in the human breast milk samples obtained during the first week (1,777.07 pg/mL) and second week postpartum (1,523.44 pg/mL), with a significantly low concentration in samples at 3-6 weeks postpartum (238.42 pg/mL; p < 0.0001). Human breast milk at different weeks postpartum stimulated higher CCL20 secretion by oral keratinocytes compared with bovine milk (p < 0.05). Such stimulation had no association with breast milk lactoferrin concentration. CONCLUSION: CCl20 is present at high levels in human milk, predominantly in the first and second week postpartum, but at significantly lower levels at 3-6 weeks postpartum. Human milk is capable of stimulating CCL20 secretion by oral keratinocytes, and this induction had no association with breast milk lactoferrin concentration.

Congenital ocular toxoplasmosis in consecutive siblings / Toxoplasmose ocular congênita em irmãos consecutivos

ABSTRACT Toxoplasma gondii infection can cause ocular manifestations after acquired and congenital disease. We report two cases of symptomatic congenital toxoplasmosis with ocular involvement in non-twin siblings, with a 2-year interval between pregnancies. Vertical transmission of toxoplasmosis in successive pregnancies, which was once considered impossible, is now found to be plausible even in immunocompetent subjects.

RESUMO A infecção pelo Toxoplasma gondii pode causar manifestações oculares tanto após a sua forma congênita quanto a sua forma adquirida. Reportamos aqui dois casos de toxoplasmose congênita sintomática com envolvimento ocular em irmãos não gêmeos, com intervalo de 2 anos entre gestações. A transmissão vertical da toxoplasmose em gestações sucessivas, outrora considerada impossível, é um evento plausível mesmo em indivíduos imunocompetentes.

Congenital cytomegalovirus infection as a cause of sensorineural hearing loss in a highly immune population.

BACKGROUND: The burden of congenital cytomegalovirus (CMV)-associated sensorineural hearing loss (SNHL) in populations with CMV seroprevalence approaching 100% is unknown. The purpose of this study was to assess the rate, associated factors, and predictors of SNHL in CMV-infected infants identified by newborn screening in a highly seropositive maternal population. METHODS: Newborns with positive saliva CMV-DNA that was confirmed by virus isolation in the first 2 weeks of life were enrolled in a prospective follow-up study to monitor hearing outcome. RESULTS: Of 12,195 infants screened, 121 (1%) were infected with CMV and 12 (10%) had symptomatic infection at birth. Hearing function could be assessed in 102/121 children who underwent at least one auditory brainstem evoked response testing at a median age of 12 months. SNHL was observed in 10/102 (9.8%; 95% confidence interval: 5.1-16.7) children. Median age at the latest hearing evaluation was 47 months (12-84 months). Profound loss (>90 dB) was found in 4/5 children with bilateral SNHL while all 5 children with unilateral loss had moderate to severe deficit. The presence of symptomatic infection at birth (odds ratio, 38.1; 95% confidence interval: 1.6-916.7) was independently associated with SNHL after adjusting for intrauterine growth restriction, gestational age, gravidity, and maternal age. Among 10 infants with SNHL, 6 (60%) were born to mothers with nonprimary CMV infection. CONCLUSIONS: Even in populations with near universal immunity to CMV, congenital CMV infection is a significant cause of SNHL demonstrating the importance of CMV as a major cause of SNHL in children worldwide. As in other populations, SNHL is more frequently observed in symptomatic CMV infection.

Infectious disease morbidity among young HIV-1-exposed but uninfected infants in Latin American and Caribbean countries: the National Institute of Child Health and Human Development International Site Development Initiative Perinatal Study.

OBJECTIVE: The goal was to describe the frequency, characteristics, and correlates of infectious disease morbidity during the first 6 months of life among HIV-1-exposed but uninfected infants. METHODS: The study population consisted of infants enrolled in the National Institute of Child Health and Human Development International Site Development Initiative Perinatal Study who were HIV-1 uninfected and had follow-up data through the 6-month study visit. Definitive and presumed infections were recorded at study visits (birth, 6-12 weeks, and 6 months). RESULTS: Of 462 HIV-1-uninfected infants with 11,644 child-weeks of observation, 283 experienced > or = 1 infection. These 283 infants experienced 522 infections (1.8 infections per infant). The overall incidence rate of infections was 4.5 cases per 100 child-weeks of observation. Overall, the most common infections were skin or mucous membrane infections (1.9 cases per 100 child-weeks) and respiratory tract infections (1.7 cases per 100 child-weeks). Thirty-six percent of infants had > 1 respiratory tract infection (1.8 cases per 100 child-weeks). Incidence rates of upper and lower respiratory tract infections were similar (0.89 cases per 100 child-weeks and 0.9 cases per 100 child-weeks, respectively). Cutaneous and/or oral candidiasis occurred in 48 neonates (10.3%) and 92 older infants (19.3%). Early neonatal sepsis was diagnosed in 12 infants (26.0 cases per 1000 infants). Overall, 81 of 462 (17.5%) infants were hospitalized with an infection. Infants with lower respiratory tract infections were hospitalized frequently (40.7%). The occurrence of > or = 1 neonatal infection was associated with more-advanced maternal HIV-1 disease, tobacco use during pregnancy, infant anemia, and crowding. Lower maternal CD4+ cell counts, receipt of intrapartum antibiotic treatment, and country of residence were associated with postneonatal infections. CONCLUSIONS: Close monitoring of HIV-1-exposed infants, especially those who are anemic at birth or whose mothers have more-advanced HIV-1 disease or who smoked during pregnancy, remains important.

Prevalência e aspectos clínicos da infecçäo congênita por citomegalovirus / Prevalence and clinical aspects of congenital cytomegalovirus infection

Objetivos: Determinar a prevalência da infecçäo congênita por citomegalovirus (CMV), bem como avaliar o palel desse agente como causa de doença congênita r descrever as principais manifestaçöes clínicas dessa doença em crianças atendidas em hospital universitário de Ribeiräo Preto. Casuística e métodos: Para determinaçäo da prevalência da infecçäo congênita, foram estudados 189 recém-nascidos e suas mäes, constituindo um primeiro grupo de estudo. Para avaliaçäo da importância do CMV na etiologia da doença congênita e descriçäo das manifestaçöes clínicas da citomegalovirose congênita, foram incluídos outros 130 recém-nascidos e 74 lactentes com clínica sugestiva de infecçäo congênita, constituindo um segundo grupo. O diagnóstico laboratorial foi realizado pelo isolamento viral na urina em cultura de fibroblastos humanos, pela detecçäo do DNA viral na urina através da reaçäo de amplificaçäo gênica catalizada pela polimerase e pela reaçäo de imunofluorescência para pesquisa de IgM e IgG específicos anti-CMV. Resultados: A prelência da infecçäo congênita foi de 2,6 por cento e 95 por cento das mäes tinham IgG anti-CMV. Todas as crianças infectadas do primeiro grupo eram assintomáticas ao nascimento, porém em uma evidenciaram-se calcificaçöes intracranianas ao exame radiológico. No segundo grupo de estudo, CMV foi detectado na urina 12(5,9 por cento) das crianças com apresentaçäo clínica compatível com doença congênita. Destas, em 10 (83 por cento), o diagnóstico foi relaizado após o período neonatal. Os achados clínicos incluíram hepatoesplenomegalia (75 por cento), icterícia neonatal em hiperbilirrubinemia direta (42 por cento) e anormalidades neurológicas caracterizadas por microcefalia e calcificaçöes intracranianas (42 por cento). Conclusöes: Observou-se uma prevalência de infecçäo congênita por CMV similar à encontrada nos estudos realizados em populaçöes de soroprevalência elevada para CMV. Crianças com citomegalovirose assintomática podem ter acomentimento do SNC, clinicamente imperceptível ao nascimento, e crianças sintomáticas apresentam doença multissistêmica. O diagnóstico diferencial de qualquer recém-nascido com anormalidades, incluindo envolvimento hepático, hematopoético e neurológico, deve incluir pesquisa para citomegalovirose congênita. Os CMV mostraram ser agaentes importantes na etiologia dessas afecçöes, e a grande maioria das crianças sintomáticas foram identificadas após o período neonatal, dificultando um diagnóstico definitivo

Infecçäo perinatal por citomegalovirus: muito freqüente mas pouco diaagnosticada / Perinatal cytomegalovirus infection: commonly occurring but rarely diagnosed

Objetivo: Avaliar a freqüência da infecçäo d perinatal por citomegalovirus (CMV) em lactentes e descrever a sua apresentaçäo clínica. Casuística e métodos: Foram estudados, prospectivamente, 34 recém-nascidos até o quarto mês de vida. Colheram-se amostras de urina ao nascimento, com 15 dias e mensalmente, bem como amostras de sangue ao nascimento e ao terceiro mês de vida. O diagnóstico laboratorial de citomegalovirose foi realizado pela detecçäo dos CMV na urina por isolamento viral de culturas de células e por detecçäo de DNA viral através da reaçäo de amplificaçäo gênica catalisada pela polimerase (PCR). Em todas as crianças foi excluído o diagnóstico de citomegalovirose congênita. Resultados: A incidência da infecçäo perinatal foi de 38,2 por cento (13/34) e apenas três dessas crianças apresentaram manifestaçöes clínicas. Obsevou-se um caso com quadro respitatório e diarréia, e outros dois pacientes apresentaram esplenomegalia. Conclusöes: Obsevou-se uma elevada taxa de incidência de infecçäo perinatal por CMV. Das crianças infectadas, 23 por cento apresentaram sintomas. Esses resultados estimulam a que se faça a pesquisa dos CMV como parte da investigaçäo etiológica de pneumonites e esplenomegalia em lactentes jovens