145 research outputs found
What can volunteer co-providers contribute to health systems? The role of people living with HIV in the Thai paediatric HIV programme
In Thailand people living with HIV (PLHIV) have played a major role in shaping policy and practice. They have acted as volunteer co-providers, although their potential in terms of paediatric service provision has seldom been explored from a health systems perspective. We describe the Thai paediatric HIV care system and use both demand- and supply-side perspectives to explore the impact, opportunities and challenges of PLHIV acting as volunteer co-providers.
We employed qualitative methods to assess experiences and perceptions and triangulate stakeholder perspectives. Data were collected in Khon Kaen province, in the poorest Northeastern region of Thailand: three focus group discussions and two workshops (total participants n = 31) with co-providers and hospital staff; interviews with ART service-users (n = 35). Nationally, key informant interviews were conducted with policy actors (n = 20).
Volunteer co-providers were found to be ideally placed to broker the link between clinic and communities for HIV infected children and played an important part in the vital psychosocial support component of HIV care. As co-providers they were recognized as having multiple roles linking and delivering services in clinics and communities. Clear emerging needs include strengthened coordination and training as well as strategies to support funding.
Using motivated volunteers with a shared HIV status as co-providers for specific clinical services can contribute to strengthening health systems in Asia; they are critical players in delivering care (supply side) and being responsive to service-users needs (demand side). Co-providers blur the boundaries between these two spheres. Sustaining and optimising co-providers' contribution to health systems strengthening requires a health systems approach. Our findings help to guide policy makers and service providers on how to balance clinical priorities with psycho-social responsiveness and on how best to integrate the views and experience of volunteers into a holistic model of care
HIV-1 RT Inhibitors with a Novel Mechanism of Action: NNRTIs that Compete with the Nucleotide Substrate
HIV-1 reverse transcriptase (RT) inhibitors currently used in antiretroviral therapy can be divided into two classes: (i) nucleoside analog RT inhibitors (NRTIs), which compete with natural nucleoside substrates and act as terminators of proviral DNA synthesis, and (ii) non-nucleoside RT inhibitors (NNRTIs), which bind to a hydrophobic pocket close to the RT active site. In spite of the efficiency of NRTIs and NNRTIs, the rapid emergence of multidrug-resistant mutations requires the development of new RT inhibitors with an alternative mechanism of action. Recently, several studies reported the discovery of novel non-nucleoside inhibitors with a distinct mechanism of action. Unlike classical NNRTIs, they compete with the nucleotide substrate, thus forming a new class of RT inhibitors: nucleotide-competing RT inhibitors (NcRTIs). In this review, we discuss current progress in the understanding of the peculiar behavior of these compounds
Immunologic and virologic failure after first-line NNRTI-based antiretroviral therapy in Thai HIV-infected children
<p>Abstract</p> <p>Background</p> <p>There are limited data of immunologic and virologic failure in Asian HIV-infected children using non-nucleoside reverse transcriptase inhibitor (NNRTI)-based highly active antiretroviral therapy (HAART). We examined the incidence rate of immunologic failure (IF) and virologic failure (VF) and the accuracy of using IF to predict VF in Thai HIV-infected children using first-line NNRTI-based HAART.</p> <p>Methods</p> <p>Antiretroviral (ART)-naΓ―ve HIV-infected children from 2 prospective cohorts treated with NNRTI-based HAART during 2001-2008 were included. CD4 counts were performed every 12 weeks and plasma HIV-RNA measured every 24 weeks. Immune recovery was defined as CD4%β₯25%. IF was defined as persistent decline of β₯5% in CD4% in children with CD4%<15% at baseline or decrease in CD4 count β₯30% from baseline. VF was defined as HIV-RNA>1,000 copies/ml after at least 24 weeks of HAART. Clinical and laboratory parameter changes were assessed using a paired t-test, and a time to event approach was used to assess predictors of VF. Sensitivity and specificity of IF were calculated against VF.</p> <p>Results</p> <p>107 ART-naive HIV-infected children were included, 52% female, % CDC clinical classification N:A:B:C 4:44:30:22%. Baseline data were median (IQR) age 6.2 (4.2-8.9) years, CD4% 7 (3-15), HIV-RNA 5.0 (4.9-5.5) log<sub>10</sub>copies/ml. Nevirapine (NVP) and efavirenz (EFV)-based HAART were started in 70% and 30%, respectively.</p> <p>At 96 weeks, none had progressed to a CDC clinical classification of AIDS and one had died from pneumonia. Overall, significant improvement of weight for age z-score (p = 0.014), height for age z-score, hemoglobin, and CD4 were seen (all p < 0.001). The median (IQR) CD4% at 96 weeks was 25 (18-30)%. Eighty-nine percent of children had immune recovery (CD4%β₯25%) and 75% of children had HIV-RNA <1.7log<sub>10</sub>copies/ml.</p> <p>Thirty five (32.7%) children experienced VF within 96 weeks. Of these, 24 (68.6%) and 31 (88.6%) children had VF in the first 24 and 48 weeks respectively.</p> <p>Only 1 (0.9%) child experienced IF within 96 weeks and the sensitivity (95%CI) of IF to VF was 4 (0.1-20.4)% and specificity was 100 (93.9-100)%.</p> <p>Conclusion</p> <p>Immunologic failure, as defined here, had low sensitivity compared to VF and should not be recommended to detect treatment failure. Plasma HIV-RNA should be performed twice, at weeks 24 and 48, to detect early treatment failure.</p> <p>Trial Registration</p> <p><b>Clinicaltrials.gov identification number </b><a href="http://www.clinicaltrials.gov/ct2/show/NCT00476606">NCT00476606</a></p
Post-licensure, phase IV, safety study of a live attenuated Japanese encephalitis recombinant vaccine in children in Thailand
AbstractBackgroundJapanese encephalitis is a mosquito-borne viral disease endemic in most countries in Asia. A recombinant live, attenuated Japanese encephalitis virus vaccine, JE-CV, is licensed in 14 countries, including Thailand, for the prevention of Japanese encephalitis in adults and children.MethodsThis was a prospective, phase IV, open-label, multicentre, safety study of JE-CV conducted from November 2013 to April 2015, to evaluate rare serious adverse events (AEs). JE-CV was administered to 10,000 healthy children aged 9months to <5years in Thailand as a primary (Group 1) or booster (Group 2) vaccination. Serious AEs (SAEs), including AEs of special interest, up to 60days after administration were evaluated. Immediate Grade 3 systemic AEs up to 30min after JE-CV administration were also described.ResultsThe median age of participants was 1.1years in Group 1 and 3.8years in Group 2. SAEs were reported in 204 (3.0%) participants in Group 1 and 59 (1.9%) participants in Group 2. Among a total of 294 SAEs in 263 participants, only three events occurring in two participants were considered related to vaccination. All three cases were moderate urticaria, none of which met the definition of AEs of special interest for hypersensitivity. AEs of special interest were reported in 28 (0.4%) participants in Group 1 and 4 (0.1%) participants in Group 2; none were considered related to vaccination. Febrile convulsion was the most frequently reported AE of special interest: 25 (0.4%) participants in Group 1; and 2 (<0.1%) in Group 2. There were no cases of Japanese encephalitis reported. No Grade 3 immediate systemic AEs were reported after any JE-CV vaccination.ConclusionsOur study did not identify any new safety concerns with JE-CV and confirms its good safety profile.This study was registered on www.clinicaltrials.gov (NCT01981967; Universal Trial Number: U1111-1127-7052)
Prevalence of HIV Seropositive pregnant women and their vertical transmission rate at Srinagarind Hospital
Objectives: To assess the prevalence of HIV infection in pregnant women and to study HIV vertical transmission at Srinagarind Hospital, Faculty of Medicine, Khon Kaen University. Khon Kaen, Thailand.Materials and Methods: The data of all known HIV seropositive women attending the antenatal clinic and giving birth at Srinagarind Hospital in Khon Kaen Province during 1999-2008 were collected from their medical records. The inclusion criteria were the HIV infected pregnant women who were enrolled to our Prevention of HIV Perinatal Transmission Program and received the antiretroviral drugs for the prevention of HIV perinatal transmission. Moreover, all of the newborns received only formula feeding and their peripheral blood were tested for HIV by PCR technique at 6 weeks and 6 months after birth and for HIV-antibody (Ab) by Enzyme Immunoassay (EIA) at 18 months. The infants were concluded to be HIV infected by either at least 2 positive PCR or a positive HIV-Ab. After delivery, both mother and baby would be followed up for 2 years.Results: From 1999-2008, there were 30,926 women attended antenatal clinic and giving birth at Srinagarind Hospital. There were 28,497 (92.64%) whom received pre-test counseling and HIV testing, 154 (0.54%) were HIV seropositive. Their average age was 27.87 years, 51(32.12%) were primigravida. The average gestational age at birth was 38.10 weeks, 43 (27.92%) of the patients were delivered by cesarean section because of obstetric indications. One hundred and four children were follow-up according to schedule. The overall vertical transmission rate was 4.80%.Conclusion: The prevalence of HIV infection in pregnant women at Srinagarind Hospital was 0.54% and the vertical transmission rate was 4.80%. Compared with the national statistics, our HIV prevalence and vertical transmission rate are lower. However, comprehensive perinatal HIV prevention programs to reduce the vertical transmission rate of HIV closely to zero might be possible in the near future
A feasibility study of immediate versus deferred antiretroviral therapy in children with HIV infection
<p>Abstract</p> <p>Objective</p> <p>To evaluate the feasibility of a large immediate versus deferred antiretroviral therapy (ART) study in children.</p> <p>Methods</p> <p>We conducted an open-label pilot randomized clinical trial study in 43 Thai children with CD4 15 to 24% of starting generic AZT/3TC/NVP immediately (Arm 1) or deferring until CD4 < 15% or CDC C (Arm 2). Primary endpoints were recruitment rate, adherence to randomized treatment and retention in trial. Secondary endpoints were % with CDC C or CD4 < 15%. Children were in the trial until the last child reached 108 weeks. Intention to treat and on treatment analyses were performed.</p> <p>Results</p> <p>Recruitment took 15 months. Twenty-six of 69 (37.7%) were not eligible due mainly to low CD4%. Twenty four and 19 were randomized to arms 1 and 2 respectively. All accepted the randomized arm; however, 3 in arm 1 stopped ART and 1 in arm 2 refused to start ART. Ten/19 (53%) in arm 2 started ART. At baseline, median age was 4.8 yrs, CDC A:B were 36:7, median CD4 was 19% and viral load was 4.8 log. All in arm 1 and 17/19 in arm 2 completed the study (median of 134 weeks). No one had AIDS or death. Four in immediate arm had tuberculosis. Once started on ART, deferred arm children achieved similar CD4 and viral load response as the immediate arm. Adverse events were similar between arms. The deferred arm had a 26% ART saving.</p> <p>Conclusion</p> <p>Almost 40% of children were not eligible due mainly to low CD4% but adherence to randomized treatment and retention in trial were excellent. A larger study to evaluate when to start ART is feasible.</p
Subtype-associated differences in HIV-1 reverse transcription affect the viral replication
Background: The impact of the products of the pol gene, specifically, reverse transcriptase (RT) on HIV-1 replication, evolution, and acquisition of drug resistance has been thoroughly characterized for subtype B. For subtype C, which accounts of almost 60% of HIV cases worldwide, much less is known. It has been reported that subtype C HIV-1 isolates have a lower replication capacity than B; however, the basis of these differences remains unclear.
Results: We analyzed the impact of the pol gene products from HIV-1 B and C subtypes on the maturation of HIV virions, accumulation of reverse transcription products, integration of viral DNA, frequency of point mutations in provirus and overall viral replication. Recombinant HIV-1 viruses of B and C subtypes comprising the pol fragments encoding protease, integrase and either the whole RT or a chimeric RT from different isolates of the C and B subtypes, were used for infection of cells expressing CXCR4 or CCR5 co-receptors. The viruses carrying different fragments of pol from the isolates of B and C subtypes did not reveal differences in Gag and GagPol processing and viral RNA incorporation into the virions. However, the presence of the whole RT from subtype C, or the chimeric RT containing either the polymerase or the connection and RNase H domains from C isolates, caused significantly slower viral replication regardless of B or C viral backbone. Subtype C RT carrying viruses displayed lower levels of accumulation of strong-stop cDNA in permeabilized virions during endogenous reverse transcription, and decreased accumulation of both strong-stop and positive strand reverse transcription products in infected cells and in isolated reverse transcription complexes. This decreased accumulation correlated with lower levels of viral DNA integration in cells infected with viruses carrying the whole RT or RT domains from subtype C isolates. The single viral genome assay analysis did not reveal significant differences in the frequency of point mutations between the RT from B or C subtypes.
Conclusions: These data suggest that the whole RT as well as distinct polymerase and connection-RNase H domains from subtype C HIV-1 confer a lower level of accumulation of reverse transcripts in the virions and reverse transcription complexes as compared to subtype B, resulting in a lower overall level of virus replication
K70Q Adds High-Level Tenofovir Resistance to βQ151M Complexβ HIV Reverse Transcriptase through the Enhanced Discrimination Mechanism
HIV-1 carrying the βQ151M complexβ reverse transcriptase (RT) mutations (A62V/V75I/F77L/F116Y/Q151M, or Q151Mc) is resistant to many FDA-approved nucleoside RT inhibitors (NRTIs), but has been considered susceptible to tenofovir disoproxil fumarate (TFV-DF or TDF). We have isolated from a TFV-DF-treated HIV patient a Q151Mc-containing clinical isolate with high phenotypic resistance to TFV-DF. Analysis of the genotypic and phenotypic testing over the course of this patient's therapy lead us to hypothesize that TFV-DF resistance emerged upon appearance of the previously unreported K70Q mutation in the Q151Mc background. Virological analysis showed that HIV with only K70Q was not significantly resistant to TFV-DF. However, addition of K70Q to the Q151Mc background significantly enhanced resistance to several approved NRTIs, and also resulted in high-level (10-fold) resistance to TFV-DF. Biochemical experiments established that the increased resistance to tenofovir is not the result of enhanced excision, as K70Q/Q151Mc RT exhibited diminished, rather than enhanced ATP-based primer unblocking activity. Pre-steady state kinetic analysis of the recombinant enzymes demonstrated that addition of the K70Q mutation selectively decreases the binding of tenofovir-diphosphate (TFV-DP), resulting in reduced incorporation of TFV into the nascent DNA chain. Molecular dynamics simulations suggest that changes in the hydrogen bonding pattern in the polymerase active site of K70Q/Q151Mc RT may contribute to the observed changes in binding and incorporation of TFV-DP. The novel pattern of TFV-resistance may help adjust therapeutic strategies for NRTI-experienced patients with multi-drug resistant (MDR) mutations
Outcomes of etravirine-based antiretroviral treatment in treatment-experienced children and adolescents living with HIV in Europe and Thailand
BACKGROUND: Etravirine (ETR) is approved as a component of second or third-line antiretroviral treatment (ART) for children living with HIV. We assessed the outcomes of ETR-based ART in children in routine care in Europe and Thailand.
METHODS: Data on children aged <18Β years at ETR start were pooled from 17 observational cohorts. Characteristics at ETR start, immunological and virological outcomes at 12 months, discontinuations, adverse events (AEs) and serious adverse events (SAEs) were described. Follow-up was censored at ETR discontinuation, death or last visit.
RESULTS: 177 children ever received ETR. At ETR start, median [IQR] age was 15 [12,16]Β years, CD4 count 480 [287, 713] cells/mm3, 70% had exposure to β₯3 ART classes and 20% had viral load (VL) 3. Overall, 81 (46%) discontinued ETR by last follow-up. Median time to discontinuation was 23 [8, 47] months. Common reasons for discontinuation were treatment simplification (19%), treatment failure (16%) and toxicity (12%). Eight children (5%) had AEs causally associated with ETR, all dermatological/hypersensitivity reactions. Two were SAEs, both Stevens-Johnson Syndrome in children on regimens containing ETR and darunavir and were causally related to either drugs; both resolved following ART discontinuation.
CONCLUSION: Children receiving ETR were predominantly highly treatment-experienced, over two-thirds were virally suppressed at 12 months
Influenza vaccination for immunocompromised patients: systematic review and meta-analysis from a public health policy perspective.
Immunocompromised patients are vulnerable to severe or complicated influenza infection. Vaccination is widely recommended for this group. This systematic review and meta-analysis assesses influenza vaccination for immunocompromised patients in terms of preventing influenza-like illness and laboratory confirmed influenza, serological response and adverse events
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