Enhancing HIV Treatment Access and Outcomes Amongst HIV Infected Children and Adolescents in Resource Limited Settings

Introduction Increasing access to HIV-related care and treatment for children aged 0–18 years in resource-limited settings is an urgent global priority. In 2011–2012 the percentage increase in children accessing antiretroviral therapy was approximately half that of adults (11 vs. 21 %). We propose a model for increasing access to, and retention in, paediatric HIV care and treatment in resource-limited settings. Methods Following a rapid appraisal of recent literature seven main challenges in paediatric HIV-related care and treatment were identified: (1) lack of regular, integrated, ongoing HIV-related diagnosis; (2) weak facility-based systems for tracking and retention in care; (3) interrupted availability of dried blood spot cards (expiration/stock outs); (4) poor quality control of rapid HIV testing; (5) supply-related gaps at health facility-laboratory interface; (6) poor uptake of HIV testing, possibly relating to a fatalistic belief about HIV infection; (7) community-associated reasons e.g. non-disclosure and weak systems for social support, resulting in poor retention in care. Results To increase sustained access to paediatric HIV-related care and treatment, regular updating of Policies, review of inter-sectoral Plans (at facility and community levels) and evaluation of Programme implementation and impact (at national, subnational, facility and community levels) are non-negotiable critical elements. Additionally we recommend the intensified implementation of seven main interventions: (1) update or refresher messaging for health care staff and simple messaging for key staff at early childhood development centres and schools; (2) contact tracing, disclosure and retention monitoring; (3) paying particular attention to infant dried blood spot (DBS) stock control; (4) regular quality assurance of rapid HIV testing procedures; (5) workshops/meetings/dialogues between health facilities and laboratories to resolve transport-related gaps and to facilitate return of results to facilities; (6) community leader and health worker advocacy at creches, schools, religious centres to increase uptake of HIV testing and dispel fatalistic beliefs about HIV; (7) use of mobile communication technology (m-health) and peer/community supporters to maintain contact with patients. Discussion and Conclusion We propose that this package of facility, community and family-orientated interventions are needed to change the trajectory of the paediatric HIV epidemic and its associated patterns of morbidity and mortality, thus achieving the double dividend of improving HIV-free survival.

KIR-HLA and maternal-infant HIV-1 transmission in sub-Saharan Africa

Numerous studies have suggested a role for natural killer (NK) cells in attenuation of HIV-1 disease progression via recognition by killer-cell immunoglobulin-like receptors (KIRs) of specific HLA class I molecules. The role of KIR and HLA class I has not been addressed in the context of maternal-infant HIV-1 transmission. KIR and HLA class I B and C genes from 224 HIV-1-infected mothers and 222 infants (72 infected and 150 uninfected) from South Africa were characterized. Although a number of significant associations were determined in both the total group and in the nevirapine (NVP) exposed group, the most significant findings involved KIR2DL2 and KIR2DL3 and HLA-C. KIR2DL2/KIR2DL3 was underrepresented in intrapartum (IP)-transmitting mothers compared to non-transmitting (NT) mothers (P = 0.008) and remained significant (P = 0.036) after correction for maternal viral load (MVL). Homozygosity for KIR2DL3 alone and in combination with HLA-C allotype heterozygosity (C1C2) was elevated in IP-transmitting mothers compared to NT mothers (P = 0.034 and P = 0.01 respectively), and after MVL correction (P = 0.033 and P = 0.027, respectively). In infants, KIR2DL3 in combination with its HLA-C1 ligand (C1) as well as homozygosity for KIR2DL3 with C1C2, were both found to be underrepresented in infected infants compared to exposed uninfected infants in the total group (P = 0.06 and P = 0.038, respectively) and in the sub-group of infants whose mothers received NVP (P = 0.007 and P = 0.03, respectively). These associations were stronger post MVL adjustment (total group: P = 0.02 and P = 0.009, respectively; NVP group: P = 0.004 and P = 0.02, respectively). Upon stratification according to low and high MVL, all significant associations fell within the low MVL group, suggesting that with low viral load, the effects of genotype can be more easily detected. In conclusion this study has identified a number of significant associations that suggest an important role for NK cells in maternal-to-infant HIV-1 transmission.

Part 10: Pediatric basic and advanced life support: 2010 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations

Note From the Writing Group: Throughout this article, the reader will notice combinations of superscripted letters and numbers (eg, “Family Presence During ResuscitationPeds-003”). These callouts are hyperlinked to evidence-based worksheets, which were used in the development of this article. An appendix of worksheets, applicable to this article, is located at the end of the text. The worksheets are available in PDF format and are open access.

Cutting Edge: Unusual NK cell responses to HIV-1 peptides are associated with protection against maternal-infant transmission of HIV-1

Most infants exposed to HIV-1 in utero and at delivery do not acquire infection. We show that mothers and infants who have CD3-negative cells that respond to HIV-1 peptides are substantially less likely to transmit and acquire infection, respectively. The CD3-negative cells, shown to be NK cells, respond with remarkable specificity and high magnitude to HIV-1 peptides from Env (envelope) and Reg (regulatory) protein regions, as measured by a whole blood intracellular cytokine assay only in the context of HIV-1 infection or exposure. These findings identify an important new measure of protective immunity to HIV-1 that highlights the importance of innate immunity in preventing the establishment of HIV-1 infection.

Identification of human immunodeficiency virus-1 specific CD8+ and CD4+ T cell responses in perinatally-infected infants and their mothers

BACKGROUND

There are few data describing the specificity, breadth and magnitude of T cell responses to HIV-1 in infancy.

METHODS

HIV-specific CD8+ and CD4+ T cell responses to peptide pools representing Gag, Env, Pol, Nef and the regulatory regions (Reg) were simultaneously measured in 18 perinatally-infected infants and 14 of their chronically-infected mothers, using a whole blood interleukin-2 and interferon-gamma flow cytometric intracellular cytokine staining assay.

RESULTS

HIV-specific CD8+ T cell responses were detected in all the infants aged 6 weeks and older (range 0.1-6.62%) and their mothers (range 0.1-4.89%). HIV-specific CD4+ T cell responses were detected in 33% of the infants (range 0.11-0.54%) and 73% of the mothers (range 0.16-0.84). CD8+ T cell responses in the mothers were almost equally spread between the variable (Nef, Reg and Env) and conserved proteins (Gag and Pol). Conversely, CD8+ T cell responses to the more variable proteins dominated in the perinatally-infected infants comprising 74% of the total response. Interestingly, mothers and infants shared responses to at least one peptide pool, whereas only one mother-infant pair shared a peptide pool targeted by CD4+ T cells. Two in-utero-infected infants tested at birth had CD8+ T cell responses, and one of them had an Env-specific CD4 T cell response.

CONCLUSION

Our observations that HIV-specific CD8+ and CD4+ T cell responses can be detected in perinatally-infected infants from 6 weeks of age and that CD8+ T cell responses predominantly target the variable proteins have important implications for HIV vaccine design.

Evaluation of seven rapid HIV tests to detect HIV-exposure and seroreversion during infancy

BACKGROUND

Failure to determine the HIV status of all pregnant women impedes progress in preventing and treating paediatric HIV because vertically exposed infants are not identified for prophylaxis, early HIV diagnosis and care.

OBJECTIVES

To assess the performance of rapid HIV tests in comparison to a laboratory-based HIV ELISA test for determining HIV-exposure and excluding HIV infection during infancy.

STUDY DESIGN

Seven rapid HIV tests were evaluated on 2266 stored samples from 116 HIV-exposed infants of known HIV status at four ages during infancy. The HIV ELISA for each sample was the standard against which rapid results were assessed to establish HIV-exposure.

RESULTS

Rapid tests did not perform uniformly during infancy. For detecting HIV-exposure the sensitivity of most rapid tests to 3 months of age approached that of an HIV ELISA however only Determine maintained this sensitivity (99.7%) throughout infancy. For excluding HIV infection (i.e. for correctly identifying HIV-uninfected infants) the specificity of all rapid tests except Determine exceeded that of the HIV ELISA from 7 months of age.

CONCLUSIONS

The use of rapid tests in infancy could improve identification and care of HIV-exposed infants. Further evaluation under field conditions is required before rapid tests can be incorporated into evidence-based diagnostic algorithms.

African infants' CCL3 gene copies influence perinatal HIV transmission in the absence of maternal nevirapine

BACKGROUND

Individuals with more copies of CCL3L1 (CCR5 ligand) than their population median have been found to be less susceptible to HIV infection. We investigated whether maternal or infant CCL3L1 gene copy numbers are associated with perinatal HIV transmission when single-dose nevirapine is given for prevention.

METHOD

A nested case-control study was undertaken combining data from four cohorts including 849 HIV-infected mothers and their infants followed prospectively in Johannesburg, South Africa. Access to antiretroviral drugs for the prevention of perinatal transmission differed across the cohorts. Maternal and infant CCL3L1 gene copy numbers per diploid genome (pdg) were determined by real-time polymerase chain reaction for 79 out of 83 transmitting pairs ( approximately 10% transmission rate) and 235 randomly selected non-transmitting pairs.

RESULTS

Higher numbers of infant, but not maternal, CCL3L1 gene copies were associated with reduced HIV transmission (P = 0.004) overall, but the association was attenuated if mothers took single-dose nevirapine or if the maternal viral load was low. Maternal nevirapine was also associated with reduced spontaneously released CCL3 (P = 0.007) and phytohemagglutinin-stimulated CCL3 (P = 0.005) production in cord blood mononuclear cells from uninfected infants.

CONCLUSION

We observed a strong association between higher infant CCL3L1 gene copies and reduced susceptibility to HIV in the absence of maternal nevirapine. We also observed a reduction in newborn CCL3 production with nevirapine exposure. Taken together, we hypothesize that nevirapine may have direct or indirect effects that partly modify the role of the CCR5 ligand CCL3 in HIV transmission, obscuring the relationship between this genetic marker and perinatal HIV transmission.

Evaluation of dried whole blood spots obtained by heel or finger stick as an alternative to venous blood for diagnosis of human immunodeficiency virus type 1 infection in vertically exposed infants in the routine diagnostic laboratory

The diagnostic accuracy of the Roche Amplicor human immunodeficiency virus type 1 DNA PCR assay (version 1.5) on DNA extracted from pediatric heel prick dried blood spots using Roche MagNA Pure nucleic acid purification technology was evaluated. The methodologies transfer successfully from the labor-intensive research laboratory to the high-throughput automated routine laboratory.

Ultrasensitive human immunodeficiency virus type 1 p24 antigen assay modified for use on dried whole-blood spots as a reliable, affordable test for infant diagnosis

The ultrasensitive human immunodeficiency virus (HIV) p24 antigen assay was modified for use on pediatric dried whole-blood spots on Whatman no. 1 filter paper. The modified assay was found to be reliable and accurate, making it an affordable tool for pediatric HIV diagnosis in developing countries.

Polymerase chain reaction for diagnosis of human immunodeficiency virus infection in infancy in low resource settings

BACKGROUND

Diagnosis of human immunodeficiency virus (HIV) is essential for accessing treatment. Current HIV diagnostic protocols for infants require adaptation and validation before they can be implemented in the developing world. The timing and type of HIV assays will be dictated by country-specific circumstances and experience from similar settings. The performance of an HIV-1 DNA polymerase chain reaction (PCR) test, and in particular a single test at 6 weeks of age, in diagnosing HIV subtype C infection acquired in utero or peripartum was assessed.

METHODS

A retrospective review of 1825 Amplicor HIV-1 DNA PCR version 1.5 tests performed between 2000 and 2004 in 2 laboratories in Johannesburg, South Africa on 769 effectively non-breast-fed infants from 3 clinically well characterized cohorts was undertaken. The HIV status of each infant was used as the standard against which the HIV PCR results were compared.

RESULTS

The overall sensitivity and specificity of the HIV PCR test were 99.3 and 99.5% respectively. A single test was 98.8% sensitive and 99.4% specific in the 627 infants tested at 6 weeks of age (58 HIV-infected and 569 HIV-uninfected). Repeat testing of all positive HIV PCR tests minimized false positive results.

CONCLUSIONS

In resource-poor settings where HIV PCR testing in an environment of good laboratory practice is feasible, a single 6-week HIV DNA PCR test can increase identification of HIV-infected children substantially from current levels. Further operational research on how best to implement and monitor such a diagnostic protocol in specific local settings, especially in breast-fed infants, is necessary.

PMTCT from research to reality--results from a routine service

OBJECTIVES

Assessment of the efficacy of a prevention of mother-to-child transmission (PMTCT) programme in a routine service setting in comparison to a research environment.

DESIGN

Descriptive study over a 13-month period utilising retrospective data obtained from hospital records complemented by prospective data on a sample of patients enrolled in a study to determine an affordable HIV diagnostic protocol for infants.

SETTING

Routine PMTCT service at Coronation Women and Children's Hospital (CWCH) situated in Johannesburg and affiliated to the University of the Witwatersrand.

SUBJECTS

Pregnant women known to be HIV infected who delivered at CWCH from 1 October 2001 to 31 October 2002.

OUTCOME MEASURES

The HIV transmission rate to infants, which reflects nevirapine (NVP) delivery and infant feeding practices, and follow-up rates of perinatally exposed children.

RESULTS

Of the 8,221 deliveries, 1,234 (15%) occurred in women known to be HIV infected. HIV transmission rates of 8.7% at 6 weeks and 8.9% at 3 months of age in the study population verifies the high rate of NVP administration and the ability of women to formula-feed their babies and abstain from breast-feeding. More than one-third of infants never return for follow-up and more than 70% are lost to follow-up by 4 months of age.

CONCLUSIONS

The low HIV transmission rate confirms the efficacy of this routine service PMTCT programme. HIV-infected children are not being identified for medical management as part of PMTCT follow-up. It is imperative that record keeping is improved to facilitate ongoing monitoring.