The effect of prenatal highly active antiretroviral therapy on the transmission of congenital and perinatal/early postnatal cytomegalovirus among HIV-infected and HIV-exposed infants

Congenital cytomegalovirus infection in newborns born to HIV-infected mothers

INTRODUCTION

Congenital citomegalovirus (CMVc) infection is more common in children exposed to HIV during pregnancy, with reported rates in pre-ART era from 2 to 7%. The use of combined antiretroviral treatment (ARTc) could be a determining factor in reducing this risk of CMV transmission. The aim of this study was to describe the epidemiology of CMVc infection in newborns of HIV-infected mothers at Hospital Universitario 12 de Octubre, Madrid, Spain, from 2000 to 2017.

MATERIAL AND METHODS

An observational and retrospective study was carried out. Epidemiological and clinical variables were collected. Statistical analysis was performed with the SPSS 24.0 computer program.

RESULTS

288 mother-infant pairs were included in the study. We observed a CMVc rate of 2.1% (95% CI 0.9-4.9).

CONCLUSIONS

The rate of CMVc in HIV-exposed children observed was lower than that reported in pre-ARTc era but seems higher than those described in general population.

Congenital Co-infections Among HIV-Exposed Infants Born to Mothers on Antiretroviral Treatment in the United States

BACKGROUND

Many women living with HIV (WLHIV) are co-infected with cytomegalovirus (CMV), Toxoplasma gondii (T gondii), and/or hepatitis C virus (HCV). The rates of congenital or perinatal transmission of these co-infections are not well defined in the current era, when most WLHIV receive antiretroviral therapy (ART) during pregnancy.

METHODS

Retrospective review of infants of WLHIV born between 2009-2019. Mothers were screened for antibodies to CMV, T. gondii, and HCV; chronic HCV infection was confirmed using plasma RNA PCR. Infants whose mothers had positive/unknown serostatus were screened for CMV using urine or saliva DNA PCR or culture at ≤3 weeks of life; T. gondii using serology at ≤1 month; and HCV using plasma RNA PCR at ≤6 months and serology at ≥12 months.

RESULTS

The study included 264 infants from 255 pregnancies in 191 mothers. At delivery, the median (IQR) CD4 count was 569 (406-748) cells/mm³ and plasma HIV load was 0 (0-24) RNA copies/mL. Among 243 infants born to CMV-seropositive (209) or CMV-missed serostatus (25) mothers, 163 (67.1%) were tested for CMV. Four infants had CMV detected, resulting in a rate of congenital infection of 2.5%. Among 65 infants from 54 (21.2%) pregnancies in T. gondii-seropositive women and 8 in women with unknown T. gondii-serostatus, one acquired congenital toxoplasmosis in the setting of acute maternal T. gondii infection. There were no episodes of vertical transmission from mothers with latent toxoplasmosis. Among 18 infants from 13 (5.1%) pregnancies in HCV RNA PCR-positive women and 4 in women with unknown HCV serostatus, there were no congenital or perinatal HCV transmissions.

CONCLUSIONS

In a US cohort of pregnant WLHIV on ART, we identified high maternal CMV seroprevalence and a high rate of congenital CMV infection. We did not identify any congenital or perinatal transmissions of T. gondii or HCV among mothers who had latent or chronic infections. Our data support screening pregnant WLHIV and their infants for CMV and suggest that the rates of congenital and perinatal T. gondii and HCV infections among infants born to WLHIV on ART may be lower in the era of effective ART.

Child HIV Exposure and CMV Seroprevalence in Botswana: No Associations With 24-Month Growth and Neurodevelopment

Background

We sought to identify predictors of child cytomegalovirus (CMV) infection overall and by maternal HIV status and to assess associations of child CMV status with growth and neurodevelopmental outcomes at 24 months of age in Botswana.

Methods

Data and samples were used from the Botswana-based observational Tshipidi study (2010–2014), enrolling pregnant women living with and without HIV and following their infants through 2 years of age. Child plasma samples were tested at 18 months of age for anti-CMV immunoglobulin G (IgG). Associations were assessed between detectable anti-CMV IgG and growth (using the World Health Organization Child Growth Standards) and neurodevelopment (using the Bayley Scales of Infant and Toddler Development III and the Developmental Milestones Checklist) at 24 months of age.

Results

Of 317 children, 215 (68%) had detectable anti-CMV IgG at 18 months of age. Comparatively, 83% (n = 178) of HIV-unexposed uninfected (HUU) children had positive CMV serology vs 47% (n = 139) of HIV-exposed uninfected (HEU) children (P < .01); 100% of HUU vs 10.5% of HEU children breastfed. Child CMV infection was not associated with weight-for-age, weight-for-length, or length-for-age z-scores at 24 months. In HUU children, CMV infection was associated with smaller head circumference (P < .01). No difference was observed by child CMV status in any neurodevelopmental domain at 24 months.

Conclusions

We observed high CMV seropositivity in 18-month-old children in Botswana, with higher seropositivity among breastfed (HUU) children. Positive CMV serostatus was not associated with 24-month child growth or neurodevelopmental outcomes, with the exception of smaller head circumference among HUU CMV-positive children.

Transmission of CMV, HTLV-1, and HIV through breastmilk

Breastfeeding is a crucial child survival intervention. However, the potential for transmission of viral infections from mother to child presents the dilemma of how best to interpret the benefits and risks of breastfeeding in different settings. In this Review, we compare the transmission dynamics, risk factors, and outcomes of infection with three chronic viruses transmitted through breastmilk: cytomegalovirus, human T-cell lymphotropic virus type 1, and HIV. We provide an overview of intervention approaches and discuss scientific, policy, and programming gaps in the understanding of these major global infections.

Low maternal vitamin D is associated with increased risk of congenital and peri/postnatal transmission of Cytomegalovirus in women with HIV

Background

CMV infection of the fetus or neonate can lead to devastating disease, and there are no effective prevention strategies to date. Vitamin D is a potent immunomodulator, supports antiviral immune responses, and plays an important role in placental immunity.

Methods

Retrospective cohort study to evaluate the impact of low maternal vitamin D on congenital and early postnatal transmission of CMV among HIV-infected, non-breastfeeding women and their HIV exposed but negative infants from an urban HIV clinic. Vitamin D panel was performed on stored maternal plasma obtained near time of delivery. Infant CMV testing at 0–6 months included urine and oral cultures, and/or serum polymerase chain reaction testing.

Results

Cohort included 340 mother-infant pairs (births 1991–2014). Among 38 infants (11%) with a CMV+ test between 0–6 months, 4.7% (14/300) had congenital CMV transmission (CMV+ test 0–3 weeks), and 7.6% (24/315) had peri/postnatal CMV (CMV+ test >3 weeks-6 months). Women with lower calcitriol (1,25-dihydroxyvitamin D), the active form of vitamin D, were more likely to have an infant with congenital (OR 12.2 [95% CI 1.61–92.2] P = 0.02) and peri/postnatal (OR 9.84 [95% CI 2.63–36.8] P = 0.0007) infections in multivariate analyses, independent of maternal HIV viral load and CD4 count.

Conclusion

This study demonstrates an association between inadequate maternal calcitriol during pregnancy and increased congenital and early postnatal acquisition of CMV among non-breastfeeding women with HIV and their HIV negative infants.

Birth Prevalence of Congenital Cytomegalovirus Infection in HIV-Exposed Uninfected Children in the Era of Combination Antiretroviral Therapy

OBJECTIVES

To estimate birth prevalence of congenital cytomegalovirus (cCMV) in HIV-exposed uninfected children born in the current era of combination antiretroviral therapy and describe cCMV-related neurodevelopmental and hearing outcomes.

STUDY DESIGN

The Surveillance Monitoring for ART Toxicities cohort study follows HIV-exposed uninfected children at 22 sites in the US and Puerto Rico. Birth cCMV prevalence was estimated in a subset of participants who had blood pellets collected within three weeks of birth and underwent ≥1 of 6 assessments evaluating cognitive and language development including an audiologic examination between 1 and 5 years of age. Detection of CMV DNA by polymerase chain reaction testing of peripheral blood mononuclear cells was used to diagnose cCMV. Proportions of suboptimal assessment scores were compared by cCMV status using Fisher exact test.

RESULTS

Mothers of 895 eligible HIV-exposed uninfected children delivered between 2007 and 2015. Most (90%) were on combination antiretroviral therapy, 88% had an HIV viral load of ≤400 copies/mL, and 93% had CD4 cell counts of ≥200 cells/μL. Eight infants were diagnosed with cCMV, yielding an estimated prevalence of 0.89% (95% CI, 0.39%-1.75%). After adjusting for a sensitivity of 70%-75% for the testing method, projected prevalence was 1.2%-1.3%. No differences were observed in cognitive, language and hearing assessments by cCMV status.

CONCLUSIONS

Although birth cCMV prevalence in HIV-exposed uninfected children born to women with well-controlled HIV is trending down compared with earlier combination antiretroviral therapy-era estimates, it is above the 0.4% reported for the general US population. HIV-exposed uninfected children remain at increased risk for cCMV.

Cytomegalovirus Viremia in HIV-1 Subtype C Positive Women at Delivery in Botswana and Adverse Birth/Infant Health Outcomes

BACKGROUND

We evaluated the association between maternal cytomegalovirus (CMV) viremia during pregnancy and adverse birth and infant health outcomes in HIV-infected mothers and their HIV-exposed uninfected infants.

METHODS

HIV-positive women and their infants were followed prospectively from pregnancy through 2 years postpartum in the "Tshipidi" study in Botswana. We analyzed the association between detectable CMV DNA in maternal blood at delivery and adverse birth outcomes (stillbirth, preterm delivery, small for gestational age, or birth defect), as well as infant hospitalization and mortality through 24 months.

RESULTS

We measured CMV DNA in blood samples from 350 (77.1%) of 454 HIV-positive women from the Tshipidi study. The median maternal CD4 count was 422 cells/mL, and median HIV-1 RNA at entry was 3.2 log10 copies/mL. Fifty-one (14.6%) women had detectable CMV DNA. In unadjusted analyses, detectable CMV DNA was associated with higher maternal HIV-1 RNA [odds ratio (OR) 1.4, 95% confidence interval (CI): 1.1 to 1.9], presence of a birth defect (OR 9.8, 95% CI: 1.6 to 60.3), and occurrence of any adverse birth outcome (OR 2.0, 95% CI: 1.04 to 3.95). In multivariable analysis, we observed a trend toward association between detectable maternal CMV DNA and occurrence of any adverse birth outcome (adjusted OR 1.9, 95% CI: 0.96 to 3.8). Maternal CMV viremia was not associated with infant hospitalization and/or death by 24 months.

CONCLUSIONS

Approximately 1 in 6 HIV-positive women in Botswana had detectable CMV DNA in blood at delivery. The presence of maternal CMV viremia had a borderline association with adverse birth outcomes but not with 24-month morbidity or mortality in HIV-exposed uninfected children.

Congenital Cytomegalovirus and HIV Perinatal Transmission

BACKGROUND

Congenital cytomegalovirus (CMV) infection (cCMV) is an important cause of hearing loss and cognitive impairment. Prior studies suggest that HIV-exposed children are at higher risk of acquiring cCMV. We assessed the presence, magnitude and risk factors associated with cCMV among infants born to HIV-infected women, who were not receiving antiretrovirals during pregnancy.

METHODS

cCMV and urinary CMV load were determined in a cohort of infants born to HIV-infected women not receiving antiretrovirals during pregnancy. Neonatal urines obtained at birth were tested for CMV DNA by qualitative and reflex quantitative real-time polymerase chain reaction.

RESULTS

Urine specimens were available for 992 (58.9%) of 1684 infants; 64 (6.5%) were CMV-positive. Mean CMV load (VL) was 470,276 copies/ml (range: < 200-2,000,000 copies/ml). Among 89 HIV-infected infants, 16 (18%) had cCMV versus 42 (4.9%) of 858 HIV-exposed, uninfected infants (P < 0.0001). cCMV was present in 23.2% of infants with in utero and 9.1% infants with intrapartum HIV infection (P < 0.0001). Rates of cCMV among HIV-infected infants were 4-fold greater (adjusted OR, 4.4; 95% CI: 2.3-8.2) and 6-fold greater among HIV in utero-infected infants (adjusted OR, 6; 95% CI: 3-12.1) compared with HIV-exposed, uninfected infants. cCMV was not associated with mode of delivery, gestational age, Apgar scores, 6-month infant mortality, maternal age, race/ethnicity, HIV viral load or CD4 count. Primary cCMV risk factors included infant HIV-infection, particularly in utero infection.

CONCLUSION

High rates of cCMV with high urinary CMV VL were observed in HIV-exposed infants. In utero HIV infection appears to be a major risk factor for cCMV in infants whose mothers have not received combination antiretroviral therapy in pregnancy.

Factors Associated with Lower Respiratory Tract Infections in HIV-Exposed Uninfected Infants

To identify factors that predispose human immunodeficiency virus (HIV)-exposed uninfected infants (HEUs) to higher incidence of severe infections, hospitalization, and death in the first 6-24 months of life compared with HEUs with and without lower respiratory tract infection (LRTI) in the first 6 months of life. Nested case-control study of 107 LRTI+ infants enrolled in the International Site Development Initiative (NISDI) Perinatal and Longitudinal Study in Latin American Countries (LILAC) studies with and 140 LRTI- in the first 6 months, matched by date and place of birth. Infants and mothers had plasma antibodies measured against respiratory syncytial virus (RSV), parainfluenza (PIV) 1, 2, 3, influenza, and pneumococcus 1, 5, 6B, and 14. Compared with LRTI-, mothers of LRTI+ HEUs had lower years of education, lower CD4⁺ cells, and higher HIV plasma viral load at delivery, but similar use of antiretrovirals and cotrimoxazole and other sociodemographic characteristics. LRTI+ and LRTI- HEUs had similar demographic and hematological characteristics and antibody concentrations against respiratory pathogens at birth. At 6 months, the rates of seroconversions to respiratory pathogens and antibody responses to tetanus vaccine were also similar. However, antibody concentrations to RSV were significantly higher in LRTI+ compared with LRTI- HEUs and marginally higher to PIV1. Maternal factors associated with advanced HIV disease, but unrelated to the use of antiretrovirals, cotrimoxazole, or the level of maternal antibodies against respiratory pathogens, contribute to the increased risk of LRTI in HEUs. In HEUs, antiretroviral and cotrimoxazole use, exposure to respiratory pathogens and humoral immune responses were not associated with the incidence of LRTI.

Congenital cytomegalovirus, parvovirus and enterovirus infection in Mozambican newborns at birth: A cross-sectional survey

Background

Congenital cytomegalovirus (cCMV) infection is the most prevalent congenital infection acquired worldwide, with higher incidence in developing countries and among HIV-exposed children. Less is known regarding vertical transmission of parvovirus B19 (B19V) and enterovirus (EV). We aimed to assess the prevalence of CMV, B19V and EV vertical transmission and compare results of screening of congenital CMV obtained from two different specimens in a semirural Mozambican maternity.

Methods

A cross sectional study was conducted among pregnant mothers attending Manhiça District Hospital upon delivery. Information on maternal risk factors was ascertained. Dried umbilical cord (DUC) samples were collected in filter paper for CMV, B19V and EV detection by real-time polymerase chain reaction (RT-PCR), and nasopharyngeal aspirates (NPA) to test for CMV by RT-PCR. Maternal blood samples and placental biopsy samples were also obtained to investigate CMV maternal serology, HIV status and immunopathology.

Results

From September 2014 to January 2015, 118 mothers/newborn pairs were recruited. Prevalence of maternal HIV infection was 31.4% (37/118). CMV RT-PCR was positive in 3/115 (2.6%) of DUC samples and in 3/96 (6.3%) of NPA samples obtained from neonates. The concordance of the RT-PCR assay through DUC with their correspondent NPA sample was moderate (Kappa = 0.42 and p<0.001. No differences on cCMV prevalence were found among HIV-exposed and unexposed. All (100%) mothers were seropositive for CMV IgG. RT-PCR of EV and B19V in DUC were both negative in all screened cases. No histological specific findings were found in placental tissues. No risk factors associated to vertical transmission of these viral infections were found.

Conclusions

This study indicates the significant occurrence of vertical transmission of CMV in southern Mozambique. Larger studies are needed to evaluate the true burden, clinical relevance and consequences of congenital infections with such pathogens in resource-constrained settings.

Maternal Highly Active Antiretroviral Therapy Reduces Vertical Cytomegalovirus Transmission But Does Not Reduce Breast Milk Cytomegalovirus Levels

To evaluate the impact of highly active antiretroviral therapy (HAART) on CMV transmission and breast milk level in the context of maternal HIV. Specimens from a randomized trial conducted in Nairobi, Kenya between 2003-2005 were used to compare CMV transmission and breast milk levels between mother-infant pairs randomized to HAART versus short-course antenatal zidovudine plus single-dose nevirapine (ZDV/sdNVP) for prevention of mother-to-child HIV transmission (PMTCT). Fifty-one antiretroviral-naïve women ≤32 weeks gestation, and CD4 between 200-500 cells/mm³ were randomized at 34 weeks to begin either antenatal ZDV/sdNVP, or HAART through 6 months postpartum. Mean breast milk CMV levels and transmission were compared between arms. Age, sociodemographics, CD4%, and HIV plasma RNA viral load were similar between arms at baseline. CMV viral loads were measured from 243 infant plasma and 185 breast milk specimens during the first year postpartum. The probability of infant CMV infection at 12 months was 19% lower in the HAART arm compared to ZDV/sdNVP (75% vs. 94%, p = .04). All women had CMV detected in breast milk, with 72%, 98%, and 97% testing positive during the first, second, and third weeks postpartum, respectively. There was a trend for early higher mean breast milk CMV level in the HAART arm at 1 week (p = .08), and there was significantly slower decline in breast milk CMV levels (area under the curve, p = .01). HAART started during the third trimester may decrease infant CMV infections, by mechanisms independent of breast milk CMV levels.

CLINICAL TRIALS REGISTRATION

NCT00167674.

Cytomegalovirus infection in HIV-infected versus non-infected infants and HIV disease progression in Cytomegalovirus infected versus non infected infants early treated with cART in the ANRS 12140-Pediacam study in Cameroon

Background

The outcome of CMV/HIV co-infection in infants treated early with combined antiretroviral therapy (cART) in resource-limited settings has not been described.

We aimed to estimate the prevalence and identify factors associated with early CMV infection in HIV-infected and non-infected infants included in a study in Cameroon, and to compare HIV disease progression and survival after 1 year of early cART, following infants’ CMV status.

Methods

HIV-infected infants followed from birth or from HIV diagnosis before 7 months old and HIV-uninfected infants born to HIV-infected or uninfected mothers were tested for CMV at a median age of 4.0 months [Interquartile range (IQR): 3.4–4.9]. Multivariable logistic regression was performed to identify factors associated with CMV infection. Early cART was offered to HIV-infected infants: mortality, immunological and virological outcomes were assessed.

Results

Three hundred and sixty-nine infants were tested. The proportion of infants infected with CMV at baseline was significantly higher in HIV-infected than in HIV-uninfected groups (58.9% (86/146) vs 30.0% (67/223), p < 0.001). At baseline, median CMV viral load was higher in HIV-infected (3.7 log copies/ml [IQR; 3.1–4.3]) than in HIV-uninfected infants (2.8 log copies [IQR; 2.1–3.4], p < 0.001). cART was initiated in 90% of HIV-infected infants (132/146) at a median age of 4.0 months (IQR; 3.2–5.9); in this sub-group CMV infection was independently associated with being followed from the time of HIV diagnosis rather than from birth (aOR = 3.1, 95%CI [1.2–8.0]), born to a non-single mother (aOR = 3.4[1.4–8.1]), and breastfeeding (aOR = 7.3 [2.7–19.4]). HIV-infected infants were retested after a median of 7.1 months [4.8–9.5]: CMV was undetectable in 37 of the 61 (60.7%) initially CMV-infected cases and became detectable in 8 of the 38 (21.1%) initially CMV-negative cases. After 1 year of cART, the probability of death (0.185 vs 0.203; p = 0.75), the proportion of cases with HIV RNA viral load <400 copies/ml (75.5% vs 61.5%; p = 0.17) and the mean CD4 percentage increase (10.97% vs 6.88%; p = 0.15) did not differ between CMV+ and CMV- infants.

Conclusions

We observed a high prevalence of CMV infection among HIV-infected infants. Early initiation of cART may have limited the negative impact of CMV even in the absence of specific anti-CMV treatment.

Maternal Antibody Responses and Nonprimary Congenital Cytomegalovirus Infection of HIV-1-Exposed Infants

Risk of congenital cytomegalovirus (cCMV) transmission is highly dependent on the presence of preexisting maternal immunity, with the lowest rates observed in CMV-seroimmune populations. Among infants of CMV-seroimmune women, those who are exposed to human immunodeficiency virus (HIV) have an increased risk of acquiring cCMV infection as compared to HIV-unexposed infants. To better understand the risk factors of nonprimary cCMV transmission in HIV-infected women, we performed a case-control study in which CMV-specific plasma antibody responses from 19 CMV-transmitting and 57 CMV-nontransmitting women with chronic CMV/HIV coinfection were evaluated for the ability to predict the risk of cCMV infection. Primary multivariable conditional logistic regression analysis revealed an association between epithelial-tropic CMV neutralizing titers and a reduced risk of cCMV transmission (odds ratio [OR], 0.18; 95% confidence interval [CI], .03-.93; P = .04), although this effect was not significant following correction for multiple comparisons (false-discovery rate, 0.12). Exploratory analysis of the CMV specificity of plasma antibodies revealed that immunoglobulin G (IgG) responses against the glycoprotein B (gB) neutralizing epitope AD-2 had a borderline association with low risk of transmission (OR, 0.72; 95% CI, .51-1.00; P = .05), although this was not confirmed in a post hoc plasma anti-AD-2 IgG blocking assay. Our data suggest that maternal neutralizing antibody responses may play a role in protection against cCMV in HIV/CMV-coinfected populations.

CMV infection in a cohort of HIV-exposed infants born to mothers receiving antiretroviral therapy during pregnancy and breastfeeding

Antiretroviral therapy has been shown to reduce rates of congenital CMV infection. Little information is available on the possible impact of antiretroviral therapy on postnatal breastfeeding-associated CMV infection acquisition. A cohort of 89 HIV-infected mothers and their children was studied. Women received antiretroviral therapy from week 25 of gestation until 6 months postpartum or indefinitely if meeting the criteria for treatment. All women were evaluated for CMV IgG presence and CMV DNA in breast milk. Children were tested for CMV infection by either the presence of IgM or the presence of CMV DNA in plasma at 1, 6 and 12 months and by the presence of IgG at 24 months. All mothers had high titers of CMV DNA in breast milk (5.7 log at Month 1 and 5.1 log at Month 6). Cumulative CMV infection rates were 60.3 % at Month 6, 69 % at Month 12 and 96.4 % at Month 24. There was a significant negative correlation between the duration of antiretroviral treatment during pregnancy and levels of CMV DNA in breast milk at Month 1 (P = 0.033). There was a trend for a correlation between high titers of CMV DNA in breast milk at 6 months and CMV infection at 6 months (P = 0.069). In this cohort, more than 95 % of the children had acquired CMV infection by 2 years of age. Besides breastfeeding, which played a major role, also horizontal transmission between 1 and 2 years was certainly relevant in determining CMV infection acquisition.

Linking Susceptibility to Infectious Diseases to Immune System Abnormalities among HIV-Exposed Uninfected Infants

HIV-exposed uninfected (HEU) infants experience increased overall mortality from infectious causes when compared to HIV-unexposed uninfected (HU) infants. This is the case in both the resource-rich and resource-limited settings. Here, we explore the concept that specific types of infectious diseases that are more common among HEU infants could provide clues as to the potential underlying immunological abnormalities. The most commonly reported infections in HEU vs. HU infants are caused by encapsulated bacteria, suggesting the existence of a less effective humoral (antibody, complement) immune response. Decreased transplacental transfer of protective maternal antibodies has consistently been observed among HEU newborns, suggesting that this may indeed be one of the key drivers of their susceptibility to infections with encapsulated bacteria. Reassuringly, HEU humoral response to vaccination appears to be well conserved. While there appears to be an increase in overall incidence of acute viral infections, no specific pattern of acute viral infections has emerged; and although there is evidence of increased chronic viral infection from perinatal transmission of hepatitis C and cytomegalovirus, no data exist to suggest an increase in adverse outcomes. Thus, no firm conclusions about antiviral effector mechanisms can be drawn. However, the most unusual of reported infections among the HEU have been opportunistic infections, suggesting the possibility of underlying defects in CD4 helper T cells and overall immune regulatory function. This may relate to the observation that the immunological profile of HEUs indicates a more activated T cell profile as well as a more inflammatory innate immune response. However, both of these observations appear transient, marked in early infancy, but no longer evident later in life. The causes of these early-life changes in immune profiles are likely multifactorial and may be related to in utero exposure to HIV, but also to increased environmental exposure to pathogens from sicker household contacts, in utero and postnatal antiretroviral drug exposure, and, in certain circumstances, differences in mode of feeding. The relative importance of each of these factors will be important to delineate in an attempt to identify those HEU at highest risk of adverse outcomes for targeted interventions.

Increased Cytomegalovirus Secretion and Risks of Infant Infection by Breastfeeding Duration From Maternal Human Immunodeficiency Virus Positive Compared to Negative Mothers in Sub-Saharan Africa

BACKGROUND

Breastfeeding imparts beneficial immune protection and nutrition to infants for healthy growth, but it is also a route for human immunodeficiency virus (HIV) and human cytomegalovirus (HCMV) infection. In previous studies, we showed that HCMV adversely affects infant development in Africa, particularly with maternal HIV exposure. In this study, we analyzed infants risks for acquisition of HCMV infection from breastfeeding and compared HIV-positive and HIV-negative mothers.

METHODS

Two cohorts were studied in Zambia. (1) Two hundred sixty-one HIV-infected and HIV-uninfected mothers were compared for HCMV deoxyribonucleic acid (DNA) loads and genotypes (glycoprotein gO) in milk from birth to 4 months postpartum. (2) Maternally HIV-exposed and HIV-unexposed infants were compared for HCMV infection risk factors. The second cohort of 460 infants, from a trial of micronutrient-fortified complementary-food to breastfeeding, were studied between 6 and 18 months of age. Human cytomegalovirus seroprevalence was assayed, and logistic regression was used to calculate risk factors for HCMV infection, including maternal HIV exposure and breastfeeding duration.

RESULTS

Human cytomegalovirus was detected in breast milk from 3 days to 4 months postpartum, with significantly raised levels in HIV-positive women and independent of genotype. In infants, HCMV antibody seroprevalence was 83% by 18 months age. Longer breastfeeding duration increased infection risk in maternally HIV-unexposed (odds ratio [OR] = 2.69 for 18 months vs <12 months; 95% confidence interval [CI], 0.84-8.59; P = .03) and HIV-exposed infants (OR = 20.37 for >6 months vs never; 95% CI, 3.71-111.70; P < .001).

CONCLUSIONS

Prolonged breastfeeding, which is common in Africa, increased risk of HCMV infection in infants. Both HIV-positive and HIV-negative women had extended milk HCMV secretion. Women who were HIV-positive secreted higher HCMV levels, and for longer duration, with their children at increased infection risk. Human cytomegalovirus control is required to maintain health benefits of breastfeeding.

Risk of congenital cytomegalovirus infection among HIV-exposed uninfected infants is not decreased by maternal nelfinavir use during pregnancy

BACKGROUND

Congenital cytomegalovirus (cCMV) infection is common among infants born to HIV-infected women. Nelfinavir (NFV), an antiretroviral drug that is safe during pregnancy, inhibits CMV replication in vitro at concentrations that standard doses achieve in plasma. We hypothesized that infants born to women receiving NFV for prevention of mother-to-child transmission of HIV (PMTCT) would have a reduced prevalence of cCMV infection.

METHODS

The prevalence of cCMV infection was compared among HIV-uninfected infants whose HIV-infected mothers either received NFV for >4 weeks during pregnancy (NFV-exposed) or did not receive any NFV in pregnancy (NFV-unexposed). CMV PCR was performed on infant blood samples collected at <3 weeks from birth.

RESULTS

Of the 1,255 women included, 314 received NFV for >4 weeks during pregnancy and 941 did not receive any NFV during pregnancy. The overall prevalence of cCMV infection in the infants was 2.2%, which did not differ by maternal NFV use. Maternal CD4 T cell counts were inversely correlated with risk of cCMV infection, independent of the time NFV was initiated during gestation. Infants with cCMV infection were born 0.7 weeks earlier (P = 0.010) and weighed 170 g less (P = 0.009) than uninfected infants.

CONCLUSION

Among HIV-exposed uninfected infants, cCMV infection was associated with adverse perinatal outcomes. NFV use in pregnancy was not associated with protection against cCMV. Safe and effective strategies to prevent cCMV infection are needed.

The rationale for third trimester testing of vertical HIV transmission in neonates with CMV infection

We report on a late-preterm neonate with severe congenital cytomegalovirus (CMV) infection, refractory to antiviral therapy with ganciclovir. Subsequent immune diagnostics led to the finding of HIV infection at day 69, even though the mother tested negative for HIV in early pregnancy. Thus, in congenital CMV infection, HIV testing should be performed to elucidate maternal HIV seroconversion during late pregnancy. Our case strongly supports third trimester screening of HIV infection acquired during pregnancy, yet recommended only for women with traditional risk factors for HIV or living in an area of high HIV prevalence.

Newborn Hearing Screenings in Human Immunodeficiency Virus-Exposed Uninfected Infants

Perinatal HIV infection and congenital cytomegalovirus (CMV) infection may increase the risk for hearing loss. We examined 1,435 infants enrolled in the Surveillance Monitoring of ART Toxicities (SMARTT) study of the Pediatric HIV/AIDS Cohort Study (PHACS) network, a prospective study of the safety of in utero antiretroviral (ARV) exposures. We determined the proportion of perinatally HIV-exposed uninfected (HEU) newborns who were referred for additional hearing testing, and evaluated the association between in utero ARV exposures and newborn hearing screening results. Using a nested case-control design, we also examined congenital CMV infection in infants with and without screening referral. Congenital CMV infection was determined based on CMV DNA detection using a nested PCR assay in peripheral blood mononuclear cells obtained within 14 days of birth. Among the 1,435 infants (70% black, 31% Hispanic, 51% male), 45 (3.1%) did not pass the hearing screen and were referred for further hearing testing. Based on exact logistic regression models controlling for maternal use of tobacco and ototoxic medications, first trimester exposure to Tenofovir was associated with lower odds of a newborn hearing screening referral [adjusted odds ratio (aOR) = 0.41, 95% confidence interval (CI): 0.14-1.00]. Exposure to Atazanavir was linked to higher odds of newborn screening referral, although not attaining significance [aOR = 1.84, 95% CI: 0.92-3.56]. Maternal ARV use may have varying effects on newborn hearing screenings. These results highlight the importance for audiologists to be knowledgeable of in utero ARV exposures in HEU children because of the possibility of higher referrals in these children.

Cytomegalovirus Infection in Human Immunodeficiency Virus (HIV)-Exposed and HIV-Infected Infants: A Systematic Review

Cytomegalovirus is highly prevalent worldwide and an important opportunistic pathogen in human immunodeficiency virus (HIV)-infected individuals. The effects of cytomegalovirus infection on HIV-exposed infants are poorly understood. We conducted a systematic review to assess the relationship between cytomegalovirus and HIV infections among HIV-exposed infants. Limited evidence suggests that HIV-induced immunosuppression in the mother increases the rate of congenital cytomegalovirus infection, while maternal antiretroviral therapy may reduce it. Limited information exists on the direction of the relationship between cytomegalovirus and HIV transmission among HIV-exposed infants. Only 2 studies have addressed this temporal sequence of events, and they suggest that cytomegalovirus can lead to subsequent HIV infection in HIV-exposed infants. Most evidence suggests that early cytomegalovirus infection accelerates HIV disease progression in infants. Gaps remain in understanding the role that cytomegalovirus infection plays in HIV-exposed infants. Decreasing cytomegalovirus transmission prenatally and in infancy might further decrease HIV transmission and lead to better health among HIV-exposed infants.

Vertical Cytomegalovirus Transmission From HIV-Infected Women Randomized to Formula-Feed or Breastfeed Their Infants

BACKGROUND

Cytomegalovirus (CMV) is associated with morbidity and mortality in human immunodeficiency virus (HIV)-exposed infants. We assessed the effect of and relative contribution of breastfeeding to CMV acquisition among infants delivered by HIV-infected mothers.

METHODS

Between 1993 and 1998 pregnant, HIV-infected women in Nairobi, Kenya, were randomly assigned to breastfeed or formula-feed their infants in an HIV transmission study. Women were allocated equally between treatment arms, and the study was not blinded. The primary endpoint of this nested study was time to infant CMV infection.

RESULTS

CMV infection was assessed in 138 breastfed and 134 formula-fed infants. Baseline characteristics were similar between arms. Breastfed infants acquired CMV earlier than formula-fed infants (median age of acquisition, 4.26 vs 9.87 months; P < .001) and had a higher 1-year probability of CMV infection (0.89 vs 0.69; P < .001). Breastfeeding was associated with a 1.6-fold increased risk of infant CMV acquisition independent of infant HIV status (multivariable hazard ratio, 1.61; 95% confidence interval, 1.20-2.16; P = .002). Approximately one third of CMV infections occurred during the peripartum period, with 40% acquired through breastfeeding and the remainder acquired through modes other than breast milk.

CONCLUSIONS

Preventing CMV acquisition may be a priority for HIV-exposed infants, but there is a narrow window of opportunity for intervention. Approaches that reduce maternal cervical and breast milk CMV reactivation may help delay infant infection.

Incidence of CMV co-infection in HIV-positive women and their neonates in a tertiary referral centre: a cohort study

Co-infection with CMV in HIV-positive pregnant women is associated with perinatal mother-to-child transmission (MTCT) of both viruses. This retrospective study reports on the incidence of maternal and neonatal CMV (presence of anti-CMV IgG and IgM, CMV DNA PCR and/or CMV virus isolation) in high-risk pregnancies due to maternal HIV infection, MTCT of HIV and/or CMV. One hundred and eleven maternal samples and 75 matched neonatal samples were available for HIV and subsequent CMV testing. In this cohort of HIV-positive pregnant women, 96 (86.5 %) serum samples were anti-CMV IgG positive. In nine (9.4 %) of these, anti-CMV IgM was detected, and in none of them a maternal primary CMV infection was suspected. Fifty-seven (51.8 %) maternal serum samples were tested retrospectively by CMV DNA PCR; one sample was positive (0.9 %). All matched neonates were tested for HIV by PCR in the first month of life; HIV transmission was detected in one case. In 74 (67.2 %) of neonates, CMV testing was performed. Sixty-six of these serum samples were tested retrospectively by CMV DNA PCR. Two newborns (2.7 %) showed laboratory markers for CMV infection (one by detection of CMV DNA in plasma, and one by isolation of CMV from a urine sample). In the follow-up, neither of these two showed clinical signs for active CMV disease. We discussed these findings in the light of the national official guidelines. All CMV transmissions occurred due to maternal reinfection or endogenous reactivation. This suggests the success of highly active antiretroviral therapy in preventing MTCT of HIV and CMV disease and highlights the importance of adequate care and follow-up.

Strategies for the prevention of mother to child transmission in Western countries: an update

BACKGROUND

During the last decades remarkable scientific advances have been made toward the prevention of HIV mother-to-child transmission, in particular in developed nations. The aim of this review was to analyze the latest findings and available international recommendations on the prevention of HIV mother-to-child transmission in high-income countries.

METHODS

We performed a literature search of the Cochrane Library, MEDLINE by PubMed and EMBASE from database inception through June 2014, using the following terms: HIV, mother-to-child transmission and mother-to-child-transmission prevention. All types of articles in the English language were included. US and available European guidelines were searched and included in the analysis.

RESULTS

One hundred fifty articles were selected for inclusion in this review.

CONCLUSIONS

Global epidemiology of HIV infection is rapidly evolving, in particular in high-resource countries. The interpretation of clinical and epidemiological studies is crucial for the development of evidence-based recommendations to guide the management of HIV mother-to-child transmission. Although significant progress has been made, heterogeneity between countries in specific interventions still exists, which may address future research.

Effect of cytomegalovirus infection on breastfeeding transmission of HIV and on the health of infants born to HIV-infected mothers

BACKGROUND

Cytomegalovirus (CMV) infection can be acquired in utero or postnatally through horizontal transmission and breastfeeding. The effect of postnatal CMV infection on postnatal HIV transmission is unknown.

METHODS

The Breastfeeding, Antiretrovirals and Nutrition study, conducted in Malawi, randomized 2369 mothers and their infants to three antiretroviral prophylaxis arms - mother (triple regimen), infant (nevirapine), or neither - for 28 weeks of breastfeeding, followed by weaning. Stored plasma and peripheral blood mononuclear cell specimens were available for 492 infants at 24 weeks and were tested with CMV PCR. Available samples from infants who were CMV PCR-positive at 24 weeks were also tested at birth (N = 242), and from infants PCR-negative at 24 weeks were tested at 48 weeks (N = 96). Cox proportional-hazards models were used to determine if CMV infection was associated with infant morbidity, mortality, or postnatal HIV acquisition.

RESULTS

At 24 weeks of age, CMV DNA was detected in 345/492 infants (70.1%); the estimated congenital CMV infection rate was 2.3%, and the estimated rate of CMV infection at 48 weeks was 78.5%. CMV infection at 24 weeks was associated with subsequent HIV acquisition through breastfeeding or infant death between 24 and 48 weeks of age (hazard ratio 4.27, P = 0.05).

CONCLUSION

Most breastfed infants of HIV-infected mothers in this resource-limited setting are infected with CMV by 24 weeks of age. Early CMV infection may be a risk factor for subsequent infant HIV infection through breastfeeding, pointing to the need for comprehensive approaches in order to achieve elimination of breastfeeding transmission of HIV.

Postnatal cytomegalovirus exposure in infants of antiretroviral-treated and untreated HIV-infected mothers

HIV-1 and CMV are important pathogens transmitted via breastfeeding. Furthermore, perinatal CMV transmission may impact growth and disease progression in HIV-exposed infants. Although maternal antiretroviral therapy reduces milk HIV-1 RNA load and postnatal transmission, its impact on milk CMV load is unclear. We examined the relationship between milk CMV and HIV-1 load (4-6 weeks postpartum) and the impact of antiretroviral treatment in 69 HIV-infected, lactating Malawian women and assessed the relationship between milk CMV load and postnatal growth in HIV-exposed, breastfed infants through six months of age. Despite an association between milk HIV-1 RNA and CMV DNA load (0.39 log(10) rise CMV load per log(10) rise HIV-1 RNA load, 95% CI 0.13-0.66), milk CMV load was similar in antiretroviral-treated and untreated women. Higher milk CMV load was associated with lower length-for-age (-0.53, 95% CI: -0.96, -0.10) and weight-for-age (-0.40, 95% CI: -0.67, -0.13) Z-score at six months in exposed, uninfected infants. As the impact of maternal antiretroviral therapy on the magnitude of postnatal CMV exposure may be limited, our findings of an inverse relationship between infant growth and milk CMV load highlight the importance of defining the role of perinatal CMV exposure on growth faltering of HIV-exposed infants.

Birth prevalence of congenital cytomegalovirus among infants of HIV-infected women on prenatal antiretroviral prophylaxis in South Africa

BACKGROUND

A high rate of congenital cytomegalovirus (CMV) has been documented in human immunodeficiency virus (HIV)-exposed infants in industrialized settings, both in the pre- and post-highly active antiretroviral therapy (HAART) era. Only limited data on the birth prevalence of congenital CMV among infants of HIV-infected women on prenatal antiretroviral (ARV) prophylaxis are available from sub-Saharan Africa, despite a high prevalence of both infections. We evaluated the prevalence of congenital CMV in HIV-exposed infants in the Western Cape, South Africa.

METHODS

HIV-infected mothers were recruited in the immediate postnatal period at a referral maternity hospital between April and October 2012. Maternal and infant clinical data and newborn saliva swabs were collected. Saliva swabs were assayed by real-time polymerase chain reaction for CMV. Data were analyzed using univariate and multivariate logistic regression analyses to determine specific demographic, maternal, and newborn characteristics associated with congenital CMV.

RESULTS

CMV was detected in 22 of 748 newborn saliva swabs (2.9%; 95% confidence interval [CI], 1.9%-4.4%). Overall, 96% of mothers used prenatal ARV prophylaxis (prenatal zidovudine, 43.9%; HAART, 52.1%). Maternal age, gestational age, prematurity (<37 weeks' gestation), type of ARV prophylaxis, length of ARV prophylaxis, birth weight, small for gestational age, and infant feeding choice were not significantly different between CMV-infected and -uninfected infants. Maternal CD4 count <200 cells/μL during pregnancy was independently associated with congenital CMV (adjusted odds ratio, 2.9; 95% CI, 1.2-7.3). A negative correlation between CMV load in saliva and maternal CD4 count was observed (r = -0.495, n = 22, P = .019).

CONCLUSIONS

The birth prevalence of congenital CMV was high despite prenatal ARV prophylaxis, and was associated with advanced maternal immunosuppression.

Maternal valacyclovir and infant cytomegalovirus acquisition: a randomized controlled trial among HIV-infected women

Background

Studies in HIV-1-infected infants and HIV-1-exposed, uninfected infants link early cytomegalovirus (CMV) acquisition with growth delay and cognitive impairment. We investigated maternal valacyclovir to delay infant acquisition of CMV.

Methods

Pregnant women with HIV-1, HSV-2 and CD4 count >250 cells/µl were randomized at 34 weeks gestation to 500 mg twice-daily valacyclovir or placebo for 12 months. Maternal CMV DNA was measured in plasma at 34 weeks gestation, in cervical secretions at 34 and 38 weeks gestation, and in breast milk at 7 postpartum timepoints; infant CMV DNA was measured in dried blood spots at 8 timepoints including birth.

Results

Among 148 women, 141 infants were compared in intent-to-treat analyses. Maternal and infant characteristics were similar between study arms. Infant CMV acquisition did not differ between study arms, with 46/70 infants (66%) in placebo arm and 47/71 infants (66%) in the valacyclovir arm acquiring CMV; median time to CMV detection did not differ. CMV DNA was detected in 92% of 542 breast milk specimens with no difference in CMV level between study arms. Change in cervical shedding of CMV DNA between baseline and 38 weeks was 0.40-log greater in the placebo arm than the valacyclovir arm (p = 0.05).

Conclusions

In this cohort of HIV-1-seropositive mothers, two-thirds of infants acquired CMV by one year. Maternal valacyclovir had no effect on timing of infant CMV acquisition or breast milk CMV viral loads, although it modestly reduced cervical CMV shedding. Maternal prophylaxis to reduce infant CMV acquisition warrants further evaluation in trials with antiviral agents.

Trials Registration

ClinicalTrials.gov NCT00530777

High rates of congenital cytomegalovirus infection linked with maternal HIV infection among neonatal admissions at a large referral center in sub-Saharan Africa

BACKGROUND

 Congenital cytomegalovirus (CMV) infection is the major infectious cause of birth defects and hearing loss globally. There is a growing recognition of the potential clinical impact of congenital CMV infections in high-seroprevalence settings.

METHODS

 A cross-sectional study of neonatal admissions at a large referral center in sub-Saharan Africa to determine the prevalence of both symptomatic and asymptomatic congenital CMV infection was performed. Real-time polymerase chain reaction was used to screen DNA-extracted sera, urine, and saliva, and an enzyme-linked immunosorbent assay was used to screen serum samples for anti-CMV immunoglobulin M. Multivariate binary logistic regression was used to identify risk factors associated with increased odds of congenital CMV infection.

RESULTS

 Congenital CMV was detected in 3.8% (15/395) of neonates. Among these infants, 6 of 15 (40%) presented with jaundice, 1 of whom also had petechiae. Congenital CMV infection was detected in 9 of 79 (11.4%; 95% confidence interval [CI], 6.1%-20.3%) neonates born to human immunodeficiency virus (HIV)-infected mothers, and both maternal HIV (odds ratio [OR], 6.661 [95% CI, 2.126-20.876], P = .001) and jaundice (OR, 5.701 [95% CI, 1.776-18.306], P = .003) were independently linked with significantly increased odds of congenital CMV infection.

CONCLUSIONS

 Congenital and early infant CMV infections may have important consequences for child health in sub-Saharan Africa and other high HIV and CMV seroprevalence populations globally.

Compartmentalized cytomegalovirus replication and transmission in the setting of maternal HIV-1 infection

BACKGROUND

Cytomegalovirus (CMV) infection is associated with adverse outcomes in human immunodeficiency virus (HIV)-exposed infants. Determinants of vertical CMV transmission in the setting of maternal HIV-1 infection are not well-defined.

METHODS

CMV and HIV-1 levels were measured in plasma, cervical secretions, and breast milk of 147 HIV-1-infected women to define correlates of maternal CMV replication and infant CMV acquisition.

RESULTS

Although few women had detectable CMV in plasma (4.8%), the majority had detectable CMV DNA in cervical secretions (66%) and breast milk (99%). There was a strong association between cervical CMV detection during pregnancy and later breast milk levels (β = 0.47; P = .005). Plasma HIV-1 level and CD4 counts were associated with CMV in the cervix and breast milk. However HIV-1 levels within the cervix and breast milk were not associated with CMV within these compartments. Maternal breast milk CMV levels (hazard ratio [HR], 1.4; P = .003) and maternal CD4 < 450 cells/mm(3) (HR, 1.8; P = .008) were independently associated with infant CMV acquisition; each log10 increase in breast milk CMV was associated with a 40% increase in infant infection. The breast milk CMV level required to attain a 50% probability of CMV transmission increased with higher maternal CD4 counts, increasing from 3.55 log10 CMV DNA copies/mL at a CD4 count of 350 cells/mm(3) to 5.50 log10 CMV DNA copies/mL at a CD4 count of 1000 cells/mm(3).

CONCLUSIONS

Breast milk CMV levels and maternal CD4 count are major determinants of CMV transmission in the setting of maternal HIV-1. Maternal immune reconstitution or lowering breast milk CMV levels may reduce vertical CMV transmission.

Probiotics, feeding tolerance, and growth: a comparison between HIV-exposed and unexposed very low birth weight infants

OBJECTIVE

The aim of this study was to compare the effect of administration of probiotics on feeding tolerance and growth outcomes of HIV-exposed (but uninfected) versus HIV non-exposed preterm infants. The null hypothesis of this study states that there will be no difference in the feeding tolerance and growth outcomes for both probiotic-exposed and unexposed premature very low birth weight infants.

METHODS

A randomized, double-blind, placebo-controlled trial was conducted during the period from July 2011 to August 2012. HIV-exposed and non-exposed premature (<34 wk gestation) infants with a birth weight of ≥500 g and ≤1250 g were randomized to receive either a probiotic mixture or placebo. The multispecies probiotic mixture consisted of 1 × 10(9) CFU, Lactobacillus rhamnosus GG and Bifidobacterium infantis per day and was administered for 28 d. Anthropometrical parameters, daily intakes, and feeding tolerance were monitored.

RESULTS

Seventy-four HIV-exposed and 110 unexposed infants were enrolled and randomized (mean birth weight 987 g ± 160 g, range, 560-1244 g; mean gestational age 28.7 wk). In all 4227 probiotic doses were administered (mean 22.9/infant). There was no difference in the average daily weight gain for treatment groups or HIV exposure. The HIV-exposed group achieved significantly higher z scores for length and head circumference at day 28 than the unexposed group (P < 0.01 and P = 0.03, respectively). There were no differences in the incidence of any signs of feeding intolerance and abdominal distension between the groups.

CONCLUSION

Probiotic supplementation did not affect growth outcomes or the incidence of any signs of feeding intolerance in HIV exposure.

The "silent" global burden of congenital cytomegalovirus

Human cytomegalovirus (CMV) is a leading cause of congenital infections worldwide. In the developed world, following the virtual elimination of circulating rubella, it is the commonest nongenetic cause of childhood hearing loss and an important cause of neurodevelopmental delay. The seroprevalence of CMV in adults and the incidence of congenital CMV infection are highest in developing countries (1 to 5% of births) and are most likely driven by nonprimary maternal infections. However, reliable estimates of prevalence and outcome from developing countries are not available. This is largely due to the dogma that maternal preexisting seroimmunity virtually eliminates the risk for sequelae. However, recent data demonstrating similar rates of sequelae, especially hearing loss, following primary and nonprimary maternal infection have underscored the importance of congenital CMV infection in resource-poor settings. Although a significant proportion of congenital CMV infections are attributable to maternal primary infection in well-resourced settings, the absence of specific interventions for seronegative mothers and uncertainty about fetal prognosis have discouraged routine maternal antibody screening. Despite these challenges, encouraging results from prototype vaccines have been reported, and the first randomized phase III trials of prenatal interventions and prolonged postnatal antiviral therapy are under way. Successful implementation of strategies to prevent or reduce the burden of congenital CMV infection will require heightened global awareness among clinicians and the general population. In this review, we highlight the global epidemiology of congenital CMV and the implications of growing knowledge in areas of prevention, diagnosis, prognosis, and management for both low (50 to 70%)- and high (>70%)-seroprevalence settings.