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.
Human cytomegalovirus (HCMV) is the leading cause of birth defects associated with infections and a leading cause of transplantation failure. This study reveals the patterns and limits of HCMV ...genomic diversity by performing a large-scale analysis of HCMV sequences sampled from human hosts, identifying the hot and cold spots of variability. We find that the diversity is unevenly distributed across three host compartments and show that HCMV populations of vascular compartments are genetically constrained while enriched for polymorphisms of glycoproteins and regulatory proteins. This work significantly advances our understanding of the genomic diversity of HCMV in humans and has clear implications for the development of therapeutics against HCMV.
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 â¼25% 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.
Sexually transmitted infections (STIs) including Chlamydia trachomatis (CT), Neisseria gonorrhoeae (NG), Treponema pallidum (TP), and cytomegalovirus (CMV) may lead to adverse pregnancy and infant ...outcomes. The role of combined maternal STIs in HIV mother-to-child transmission (MTCT) was evaluated in mother-infant pairs from NICHD HPTN 040.
Urine samples from HIV-infected pregnant women during labor were tested by polymerase chain reaction (PCR) for CT, NG, and CMV. Infant HIV infection was determined by serial HIV DNA PCR testing. Maternal syphilis was tested by VDRL and confirmatory treponemal antibodies.
A total of 899 mother-infant pairs were evaluated. Over 30% had at least one of the following infections (TP, CT, NG, and/or CMV) detected at the time of delivery. High rates of TP (8.7%), CT (17.8%), NG (4%), and CMV (6.3%) were observed. HIV MTCT was 9.1% (n = 82 infants). HIV MTCT was 12.5%, 10.3%, 11.1%, and 26.3% among infants born to women with CT, TP, NG or CMV respectively. Forty-two percent of HIV-infected infants were born to women with at least one of these 4 infections. Women with these infections were nearly twice as likely to have an HIV-infected infant (aOR 1.9, 95% CI 1.1-3.0), particularly those with 2 STIs (aOR 3.4, 95% CI 1.5-7.7). Individually, maternal CMV (aOR 4.4 1.5-13.0) and infant congenital CMV (OR 4.1, 95% CI 2.2-7.8) but not other STIs (TP, CT, or NG) were associated with an increased risk of HIV MTCT.
HIV-infected pregnant women identified during labor are at high risk for STIs. Co-infection with STIs including CMV nearly doubles HIV MTCT risk. CMV infection appears to confer the largest risk of HIV MTCT.
NCT00099359.
HIV-exposed uninfected infants (HEU) have increased morbidity and mortality due to infections in the first 6 months of life that tapers down to 2 years of life. The underlying immunologic defects ...remain undefined. We investigated antigen-presenting cells (APC) by comparing the phenotype of unstimulated APC, responses to toll-like receptor (TLR) stimulation, and ability to activate natural killer (NK) cells in 24 HEU and 64 HIV-unexposed infants (HUU) at 1-2 days of life (birth) and 28 HEU and 45 HUU at 6 months of life. At birth, unstimulated APC showed higher levels of activation and cytokine production in HEU than HUU and stimulation with TLR agonists revealed lower expression of inflammatory cytokines and activation markers, but similar expression of IL10 regulatory cytokine, in APC from HEU compared to HUU. Differences were still present at 6 months of life. From birth to 6 months, APC underwent extensive phenotypic and functional changes in HUU and minimal changes in HEU. TLR stimulation also generated lower NK cell expression of CD69 and/or IFNγ in HEU compared with HUU at birth and 6 months.
experiments showed that NK IFNγ expression depended on APC cytokine secretion in response to TLR stimulation.
IL10 supplementation decreased APC-mediated NK cell activation measured by IFNγ expression. We conclude that APC maturation was stunted or delayed in the first 6 months of life in HEU compared with HUU. Deficient inflammatory APC responses and/or the imbalance between inflammatory and regulatory responses in HEU may play an important role in their increased susceptibility to severe infections.
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.
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.
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.
Cytomegalovirus shedding is relatively common in seropositive pregnant women repeatedly assessed in different bodily fluids and is associated with close contact with family members, especially young ...children. These natural history data serve as reference for planning intervention studies.
Abstract
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.
To evaluate effects of maternal HIV and antiretroviral treatment (ART) on intrauterine fetal growth.
Prospective cohort studies of HIV and ZIKA infection among women living with HIV (WLHIV) and women ...not living with HIV (WNLHIV) conducted in Brazil and the US from 2016 to 2020.
We evaluated fetal growth via repeated ultrasounds and calculated z scores for fetal growth measures using Intergrowth-21st standards among women with singleton pregnancies. Adjusted linear mixed models were fit for each fetal growth z score by HIV status. Among WLHIV, we compared fetal growth z scores by the most common maternal ART regimens, stratified by timing of ART initiation.
We included 166 WLHIV and 705 WNLHIV; none had Zika infection. The z scores were similar for WLHIV and WNLHIV for femur length (latest third trimester median = 1.08) and estimated fetal weight (median ≈0.60); adjusted mean differences in fetal weight z scores by HIV status were less than 0.1 throughout gestation. Other fetal growth measurements were lower for WLHIV than WNLHIV early in gestation but increased more rapidly over gestation. Among WLHIV not on ART at conception, adjusted mean z scores were generally similar across regimens initiated during pregnancy but somewhat lower for atazanavir-based regimens for biparietal diameter compared with efavirenz-based or raltegravir-based regimens. Among WLHIV on ART at conception, mean z scores were similar across ART regimens.
Within our cohorts, fetal growth was lower in WLHIV than WNLHIV early in gestation but similar by the end of gestation, which is reassuring. Among WLHIV, fetal growth measures were generally similar across ART regimens evaluated.
In this randomized trial involving neonates whose HIV-infected mothers did not receive antenatal antiretroviral therapy (ART), combination ART significantly reduced intrapartum HIV infection, as ...compared with monotherapy. Three-drug ART had more side effects than two-drug ART.
Randomized, controlled studies of postexposure prophylaxis in infants born to late-presenting women with human immunodeficiency virus (HIV) infection who did not receive antiretroviral therapy (ART) in pregnancy have been performed in breast-fed populations
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but not in non–breast-fed populations of higher-income countries. Observational studies have shown reduced transmission when zidovudine therapy was initiated within 48 hours after birth and continued for 6 weeks in neonates born to untreated mothers with HIV type 1 (HIV-1) infection,
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although transmission rates in this scenario remain as high as 12 to 26%.
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In a randomized South African trial of infants born to . . .
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