Mother to child transmission of HIV: what works and how much is enough?

Incident HIV acquisition among pregnant women in Botswana: findings from the Tsepamo birth outcomes surveillance study

INTRODUCTION

In Botswana, where almost all pregnant women known to have HIV receive antiretroviral therapy, a large proportion of vertical HIV transmission may occur among women with incident undiagnosed HIV infection during pregnancy. Botswana guidelines recommend repeat HIV testing every 3 months in pregnancy, with at least one test in the third trimester. We evaluated the rate of repeat HIV testing, calculated HIV incidence during pregnancy and estimated missed seroconversions.

METHODS

In the Botswana Tsepamo Study, we abstracted HIV test dates and results from obstetric records of all women who delivered at maternity wards in 18 communities between 7th May 2017 and 20th August 2021. We defined seroconversion as an initial negative/indeterminate HIV test in pregnancy followed by a positive test during pregnancy/at delivery. The incidence rate (IR) of seroconversion was calculated among women with > = 2 known test dates. Missed seroconversions were estimated among women without a test in the third trimester by applying the IR to the time after the last HIV test until delivery.

RESULTS

Among 103,529 women delivering in the study period testing negative at the first test and with known conception and HIV test dates, 29,085 (28%) were tested in one trimester of pregnancy, 73,156 (71%) were tested in ≥ 2 trimesters of pregnancy and 9628 (9%) had a test in all trimesters. A total of 78,162 (75%) women had a third-trimester test. There were 223 seroconversions (2.58/1000 pregnancies, 0.26%) among those with ≥ 2 known HIV test dates, yielding an IR of 0.69/100 person-years. Among 25,289 women who did not have a test in the third trimester, we estimate approximately 58 seroconversions may have been missed during pregnancy due to a lack of repeat testing. Factors associated with seroconversion during pregnancy included younger age, less education and not being married.

CONCLUSIONS

More than two-thirds of women had repeat HIV testing in pregnancy and HIV incidence was low. However, an estimated 21% of seroconversions in pregnancy were likely missed due to a lack of re-testing. To reach the goal of zero new paediatric HIV infections, Botswana will need to intensify repeat HIV testing in the third trimester of pregnancy.

Pathophysiological and molecular considerations of viral and bacterial infections during maternal-fetal and -neonatal interactions of SARS-CoV-2, Zika, and Mycoplasma infectious diseases

During pregnancy, a series of physiological changes are determined at the molecular, cellular and macroscopic level that make the mother and fetus more susceptible to certain viral and bacterial infections, especially the infections in this and the companion review. Particular situations increase susceptibility to infection in neonates. The enhanced susceptibility to certain infections increases the risk of developing particular diseases that can progress to become morbidly severe. For example, during the current pandemic caused by the SARS-CoV-2 virus, epidemiological studies have established that pregnant women with COVID-19 disease are more likely to be hospitalized. However, the risk for intensive care unit admission and mechanical ventilation is not increased compared with nonpregnant women. Although much remains unknown with this particular infection, the elevated risk of progression during pregnancy towards more severe manifestations of COVID-19 disease is not associated with an increased risk of death. In addition, the epidemiological data available in neonates suggest that their risk of acquiring COVID-19 is low compared with infants (<12 months of age). However, they might be at higher risk for progression to severe COVID-19 disease compared with older children. The data on clinical presentation and disease severity among neonates are limited and based on case reports and small case series. It is well documented the importance of the Zika virus infection as the main cause of several congenital anomalies and birth defects such as microcephaly, and also adverse pregnancy outcomes. Mycoplasma infections also increase adverse pregnancy outcomes. This review will focus on the molecular, pathophysiological and biophysical characteristics of the mother/placental-fetal/neonatal interactions and the possible mechanisms of these pathogens (SARS-CoV-2, ZIKV, and Mycoplasmas) for promoting disease at this level.

The Prevention of Mother-to-Child HIV/AIDS Transmission at Public Health Centers: A Phenomenology Study

Objective:

Mothers with HIV are likely to transmit the virus to their babies during pregnancy, delivery, or through breastfeeding. According to studies, the risk of mother-to-child HIV transmission among mothers that do not receive any form of treatment during pregnancy is approximately 15-45%. In Indonesia, the lack of a prevention program for HIV led to the provision of antiretroviral therapy (ART) for the prevention of mother-to-child transmission (PMTCT). The policies, financial facilities, the healthcare system, and human resources, including health workers, are factors that influence the PMTCT. This research discusses the perceptions of several doctors and midwives regarding the prevention of mother-to-child transmission at public health centers. Furthermore, information regarding policies and implementation of the PMTCT program at public health centers in Yogyakarta was qualitatively collected through semi-structured interviews.

Methods:

This research involved 6 participants, comprising of 3 heads of public health centers and 3 midwives as the HIV/AIDS program managers. A total of 5 themes were selected for the interview, namely policies of mandatory HIV testing for pregnant mothers, inadequate knowledge of the virus, need for PMTCT training, infrastructure and facilities, and HIV retesting.

Results:

Pregnant mothers are at potential risk of exposing health workers to HIV. They are also prone to contracting the virus due to poor educational background and less exposure to health information. Therefore, midwives need Prongs 3 and 4 to avoid contracting the virus while assisting pregnant mothers. Presently, there is a shortage of health promotion media for PMTCT, which include both electronic and print educational media. Therefore, the implementation of HIV testing in Indonesia is mandatory for pregnant mothers at their first antenatal care (ANC). However, despite the importance of conducting this test before labor, there is no regulation to ensure its implementation.

Conclusion:

The success of HIV mitigation is closely associated with the participation of academicians, policymakers, and community networks in providing collaborative planning strategies for the reduction of its spread, and evaluation of the mitigation result.

In utero and peripartum antiretroviral exposure as predictor of cognition in 6- to 10-year-old HIV-exposed Ugandan children - a prospective cohort study

OBJECTIVES

To quantify association between in utero/peripartum antiretroviral (IPA) exposure and cognition, i.e. executive function (EF) and socioemotional adjustment (SEA), in school-aged Ugandan children who were perinatally HIV-infected (CPHIV, n = 100) and children who were HIV-exposed but uninfected (CHEU, n = 101).

METHODS

Children were enrolled at age 6-10 years and followed for 12 months from March 2017 to December 2018. Caregiver-reported child EF and SEA competencies were assessed using validated questionnaires at baseline, 6 and 12 months. IPA type - combination antiretroviral therapy (cART), intrapartum single-dose nevirapine ± zidovudine (sdNVP ± ZDV), nevirapine + zidovudine + lamivudine (sdNVP + ZDV + 3TC) - or no IPA (reference) was verified via medical records. IPA-related standardized mean differences (SMDs) with corresponding 95% confidence intervals (CIs) in cognitive competencies were estimated from regression models with adjustment for caregiver sociodemographic and contextual factors. Models were fitted separately for CPHIV and CHEU.

RESULTS

Among CPHIV children, cART (SMD = -0.82, 95% CI: -1.37 to -0.28) and sdNVP ± ZDV (SMD = -0.41, 95% CI: -0.81 to -0.00) vs. no IPA predicted lower executive dysfunction over 12 months. Intrapartum sdNVP + ZDV + 3TC vs. no IPA predicted executive dysfunction (SMD = 0.80, 95% CI: 0.30-1.31), SEA problems (SMD = 0.63-0.76, 95% CI: 0.00-1.24) and lower adaptive skills (SMD = -0.36, 95% CI: -0.75-0.02) over 12 months among CHEU. Further adjustment for contextual factors attenuated associations, although most remained of moderate clinical importance (|SMD| > 0.33).

CONCLUSIONS

Among CPHIV children, cART and sdNVP ± ZDV IPA exposure predicted, on average, lower executive dysfunction 6-10 years later. However, peripartum sdNVP + ZDV + 3TC predicted executive and SEA dysfunction among CHEU 6-10 years later. These data underscore the need for more research into long-term effects of in utero ART to inform development of appropriate interventions so as to mitigate cognitive sequelae.

The involvement of annexin A1 in human placental response to maternal Zika virus infection

The association of Zika virus infection (ZIKV) with congenital malformation and neurological sequelae brought a significant global concern. Recent studies have shown that maternal viral infection leads to inflammation in the placental tissue. In this context, the antiinflammatory protein annexin 1 (ANXA1) has a major determination of the resolution of inflammation and it has been positively associated with antiparasitic activity in infected placental explants. Although these effects have been explored to some degree, ANXA1 expression and potential properties have not yet been fully elucidated in placentas infected with ZIKV. This study was conducted to evaluate the histopathology, inflammatory process and elucidate if ANXA1 were differently expressed in placentas of ZIKV-infected mothers. Three classification groups were used in this study: Neg/Neg (mother and placenta negative for the virus), Pos/Neg (infected mother, but no virus detected in placenta) and Pos/Pos (mother and placenta infected with ZIKV). ANXA1 was expressed in syncytiotrophoblast cells of all studied groups, and its expression was decreased in Pos/Neg group, which displayed also an increase of the inflammatory response, as evinced from the recruitment of inflammatory cells, increased levels of placenta cytokines, and evidence of impaired tissue repair. The presence of ZIKV in placentas of Pos/Pos group shows structural alterations, including detachment and disorganization of the trophoblastic epithelium. In summary, our results suggest that maternal infection with ZIKV, even without direct tissue infection, leads to a placental inflammatory response probably related to the modulation of ANXA1. After placental infection, structural changes - including inflammatory cells influx - are observed leading to placental dysfunction and reduced fetal weight. Our study sheds additional light on the outcomes of ZIKV infection in trophoblast and reveals a potential involvement of ANXA1 in the placental biology.

Treatment adherence among mothers living with HIV in the US: a scoping review

The purpose of this review was to understand research about treatment adherence among mothers in the US who are living with HIV. Treatment adherence included Antiretroviral Therapy and attending medical care appointments. A scoping review was conducted, and five peer-reviewed databases were searched with predetermined search terms for the period of 2006-2016. Thirty-five articles were identified for the review, including (n = 17) quantitative studies, (n = 6) qualitative studies, (n = 4) reviews and (n = 8) conceptual/theoretical articles. The most frequently identified theme among the articles was prevention of mother-to-child transmission of HIV. Authors disagreed about whether parenting children was a burden or a source of strength for the affected women. Implications identified for practice included a more longitudinal approach to care for mothers, rather than focusing narrowly on prevention of transmission to infants.

Singularities of nevirapine metabolism: from sex-dependent differences to idiosyncratic toxicity

Nevirapine (NVP) is a first-generation non-nucleoside reverse transcriptase inhibitor widely used for the treatment and prophylaxis of human immunodeficiency virus infection. The drug is taken throughout the patient's life and, due to the availability of an extended-release formulation, it is administered once daily. This antiretroviral is one of the scarce examples of drugs with prescription criteria based on sex, in order to prevent adverse reactions. The therapy with NVP has been associated with potentially life-threatening liver and idiosyncratic skin toxicity. Multiple evidence has emerged regarding the formation of electrophilic NVP metabolites as crucial for adverse idiosyncratic reactions. The formation of reactive metabolites that yield covalent adducts with proteins has been demonstrated in patients under NVP-based treatment. Interestingly, several pharmacogenetic- and sex-related factors associated with NVP toxicity can be mechanistically explained by an imbalance toward increased formation of NVP-derived reactive metabolites and/or impaired detoxification capability. Moreover, the haptenation of self-proteins by these reactive species provides a plausible link between NVP bioactivation and immunotoxicity, further supporting the relevance of this toxicokinetics hypothesis. In the current paper, we review the existing knowledge and recent developments on NVP metabolism and their relation to NVP toxicity.

HIV Testing Services in Africa: Are They Sustainable?

HIV testing services (HTS) are an essential component of a national response to the HIV epidemic, and in lower and middle income countries, at least 150 million persons are tested annually. HIV testing is necessary to identify persons in need of antiretroviral treatment, which has been documented to be highly effective not only for treatment but also for prevention of HIV transmission to both adults and children. An assessment of the recent literature on sustainability of health and HIV services suggests that organizational performance, flexibility, and integration with other health interventions contribute to sustainability of HIV services and programs. This article describes the experiences of two HIV testing service providers in Uganda and Zambia as well as the track record of services to prevent mother-to-child HIV transmission to illustrate the factors of performance, flexibility, adaptability, and integration which are key to the sustainability of HIV testing services.

Nevirapine induced mitochondrial dysfunction in HepG2 cells

Nevirapine (NVP) is a non-nucleoside reverse transcriptase inhibitor frequently used in combination with other antiretroviral agents for highly active antiretroviral therapy (HAART) of patients infected with the human immunodeficiency virus type 1 (HIV-1). However NVP can cause serious, life-threatening complications. Hepatotoxicity is one of the most severe adverse effects, particularly in HIV patients with chronic hepatitis C virus co-infection as these patients can develop liver toxicity after a relatively short course of treatment. However, the mechanism of NVP-associated hepatotoxicity remains unclear. This study sought to investigate the effect of NVP on protein expression in liver cells using a proteomic approach. HepG2 cells were treated or not treated with NVP and proteins were subsequently resolved by two-dimensional gel electrophoresis. A total of 33 differentially regulated proteins were identified, of which nearly 40% (13/33) were mitochondrial proteins. While no obvious differences were observed between NVP treated and untreated cells after staining mitochondria with mitotracker, RT-PCR expression analysis of three mitochondrially encoded genes showed all were significantly up-regulated in NVP treated cells. Mitochondrial dysfunction was observed in response to treatment even with slightly sub-optimal therapeutic treatment concentrations of NVP. This study shows that NVP induces mitochondrial dysregulation in HepG2 cells.

Etiology, Antibiotic Resistance and Risk Factors for Neonatal Sepsis in a Large Referral Center in Zambia

BACKGROUND

In sub-Saharan Africa, there is scanty data on the causes of neonatal sepsis and antimicrobial resistance among common invasive pathogens that might guide policy and practice.

METHODS

A cross-sectional observational prevalence and etiology study of neonates with suspected sepsis admitted to the neonatal intensive care unit, University Teaching Hospital, Lusaka, Zambia, between October 2013 and May 2014. Data from blood cultures and phenotypic antibiotic susceptibility testing were compared with multivariate analysis of risk factors for neonatal sepsis.

RESULTS

Of 313 neonates with suspected sepsis, 54% (170/313) were male; 20% (62/313) were born to HIV-positive mothers; 33% (103/313) had positive blood cultures, of which 85% (88/103) were early-onset sepsis. Klebsiella species was the most prevalent isolate, accounting for 75% (77/103) of cases, followed by coagulase-negative staphylococci [6% (7/103)], Staphylococcus aureus [6% (6/103)], Escherichia coli [5% (5/103)] and Candida species [5% (5/103)]. For Klebsiella species, antibiotic resistance ranged from 96%-99% for World Health Organization-recommended first-line therapy (gentamicin and ampicillin/penicillin) to 94%-97% for third-generation cephalosporins. The prevalence of culture-confirmed sepsis increased from 0 to 39% during the period December 2013 to March 2014, during which time mortality increased 29%-47%; 93% (14/15) of late-onset sepsis and 82% (37/45) of early-onset sepsis aged 4-7 days were admitted >2 days before the onset of symptoms. Culture results for only 25% (26/103) of cases were available before discharge or death. Maternal HIV infection was associated with a reduced risk of neonatal sepsis [odds ratio, 0.46 (0.23-0.93); P = 0.029].

CONCLUSIONS

Outbreaks of nosocomial multiantibiotic-resistant infections are an important cause of neonatal sepsis and associated mortality. Reduced risk of neonatal sepsis associated with maternal HIV infection is counterintuitive and requires further investigation.

Infant peripheral blood repetitive element hypomethylation associated with antiretroviral therapy in utero

The use of combination antiretroviral therapy (cART) to prevent HIV mother-to-child transmission during pregnancy and delivery is generally considered safe. However, vigilant assessment of potential risks of these agents remains warranted. Epigenetic changes including DNA methylation are considered potential mechanisms linking the in utero environment with long-term health outcomes. Few studies have examined the epigenetic effects of prenatal exposure to pharmaceutical agents, including antiretroviral therapies, on children. In this study, we examined the methylation status of the LINE-1 and ALU-Yb8 repetitive elements as markers of global DNA methylation alteration in peripheral blood mononuclear cells obtained from newborns participating in the Pediatric HIV/AIDS Cohort Study SMARTT cohort of HIV-exposed, cART-exposed uninfected infants compared to a historical cohort of HIV-exposed, antiretroviral-unexposed infants from the Women and Infants Transmission Study Cohort. In linear regression models controlling for potential confounders, we found the adjusted mean difference of AluYb8 methylation of the cART-exposed compared to the -unexposed was -0.568 (95% CI: -1.023, -0.149) and for LINE-1 methylation was -1.359 (95% CI: -1.860, -0.857). Among those exposed to cART, subjects treated with atazanavir (ATV), compared to those on other treatments, had less AluYb8 methylation (-0.524, 95% CI: -0.025, -1.024). Overall, these results suggest a small but statistically significant reduction in the methylation of these repetitive elements in an HIV-exposed, cART-exposed cohort compared to an HIV-exposed, cART-unexposed historic cohort. The potential long-term implications of these differences are worthy of further examination.

Efavirenz-based antiretroviral therapy versus nevirapine-including regimens for prevention of mother-to-child transmission of HIV option B plus in resource-limited settings: is there anything missing?

In 2013, an estimated 1.5 million HIV-positive pregnant women gave birth, with 240,000 children worldwide acquiring HIV. More than 90% of new pediatric infections occurred in Sub-Saharan Africa. The latest WHO guidelines recommended efavirenz (EFV)-based antiretroviral therapy as the first-line regimen for prevention of mother-to-child transmission of HIV (PMTCT). On the other hand, some data suggest that nevirapine (NVP), a well-known antiretroviral, could still play a relevant role in PMTCT, especially in resource-limited settings (RLSs) where the fertility rate is dramatically high compared to developed countries. Given the lack of an unanimous consensus and definitive opinions, this paper goes through the reasons for WHO decisions and aims at refreshing the debate about NVP and EFV pros and cons for PMTCT in RLSs.

Injectable and implantable antiretroviral strategies for HIV prevention

Antiretroviral preexposure prophylaxis has huge potential for reducing the rates of new HIV infections in at risk populations. Oral and vaginal antiretroviral formulations have been evaluated in multiple Phase IIB and Phase III effectiveness trials and there is clear evidence that these products work when used. The converse is also true; antiretrovirals do not work when they are not used and unfortunately adherence is a problem for both HIV treatment and prevention. As a consequence, long-acting injectable and implantable antiretroviral formulations are being developed for the treatment and prevention of HIV infection. It is hoped they will reduce the burden of product adherence associated with the use of oral and topical products and improve clinical outcomes associated with their use. The purpose of this review is to summarize recent preclinical and clinical research in this area of HIV prevention.

Therapeutic drug monitoring in HIV-infected pregnant women with a focus on protease inhibitors

The goals of HIV therapy in pregnant patients are to ensure health of mother and to prevent mother to child transmission of HIV to the unborn child. Pregnancy is a time of significant physiological alterations that affect all pharmacological aspects of the antiretroviral (ARV) drugs. Studies point toward lower levels of ARVs in maternal blood especially during late stages of pregnancy. Therapeutic drug monitoring is a strategy to ensure that maternal blood contains adequate level of ARVs to achieve these targets. Pharmacokinetics and therapeutic drug monitoring studies of protease inhibitors are reviewed in this article with emphasis on darunavir which is a newer protease inhibitor gaining popularity as a therapeutic choice in pregnant patients.