• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 107
  • 9
  • 8
  • 5
  • 2
  • 1
  • Tagged with
  • 144
  • 144
  • 144
  • 144
  • 129
  • 82
  • 53
  • 50
  • 37
  • 35
  • 29
  • 28
  • 27
  • 26
  • 23
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

CHARACTERIZING THE ROLE OF TOLL-LIKE RECEPTOR 2 IN SENSING AND REGULATING HUMAN IMMUNDEFICIENCY VIRUS-1 INFECTION FROM MOTHER-TO-CHILD THROUGH BREAST MILK

Henrick, Bethany M. 10 1900 (has links)
<p>Breastfeeding from HIV-infected mothers is one of the major sources of pediatric HIV-1 infection; however, an intervention that promotes exclusive breastfeeding has significantly reduced vertical HIV transmission rates and infant mortality. The mechanisms underlying this phenomenon remain unknown; however, have been closely linked to high levels of innate immune factors in breast milk. Indeed, the level of several innate factors in breast milk correlate with protection and/or have direct anti-viral properties <em>in vitro.</em> The innate immune factor, soluble TLR2 (sTLR2) is found in high concentration in breast milk and has previously been investigated for its anti-bacterial properties; however, its anti-viral properties remain poorly understood. Thus, the research presented in this thesis extended our understanding of sTLR2 by characterizing the mechanisms by which sTLR2 inhibited HIV-induced inflammation and infection. Chapter 2 examined the predominant forms of sTLR2 in breast milk from different women, its cellular source, bioavailability and kinetics postpartum. Functionally, we confirmed sTLR2’s anti-bacterial properties and extended to show, for the first time, that sTLR2 directly inhibited HIV infection <em>in vitro.</em> Chapter 3 documented a potential mechanism of sTLR2’s direct inhibition of HIV infection <em>in vitro</em> and, investigated sTLR2 and TLR2 expression in HIV uninfected compared to HIV infected breast milk and breast milk cells, respectively. Chapter 4 investigated the role of TLR2’s recognition of novel HIV pathogen associated molecular patterns (PAMPs), and whether TLR2 expression increased HIV infection and integration. Taken together, we present novel anti-viral functions of sTLR2 by demonstrating that sTLR2 bound to specific HIV PAMPs, which led to significantly decreased HIV-induced inflammation, co-receptor expression, and HIV infection. Furthermore, we demonstrated, for the first time, that TLR2 recognizes specific HIV PAMPs, which led to significantly increased pro-inflammatory cytokine production, co-receptor expression and HIV infection. Thus, sTLR2 and TLR2 represent innate immune factors that might have preventative and therapeutic applications for both infants and adults in the future.<strong><br /> </strong></p> / Doctor of Philosophy (Medical Science)
92

Effective prevention of mother-to-child transmission of HIV at Oshakati District Health Centre in the Republic of Namibia

Shoopala, Naemi Ndahambemlela 02 1900 (has links)
The aim of this study was to assess the extent on how effective was the prevention of mother-to-child transmission of Human Immunodeficiency Virus (HIV) infection at Oshakati District Health Centre. Explanatory survey was used to conduct the research. A total of 160 nurses experienced in prevention of mother-to-child transmission and women who attended antenatal care and post natal care services participated in the study. Respondents expressed unsatisfactory with the promoting involvement of male partners, high quality voluntary counselling and testing services, couple counselling and testing, integration of Highly Active Antiretroviral Therapy services, administration of short course of Zidovudine to pregnant mothers and the provision of antiretroviral drugs to infants. Therefore, promoting involvement of male partners, couple counselling and testing, administration of short course of Zidovudine to pregnant mothers and educating women about exclusive breastfeeding prior to delivery are some of recommendations for effective prevention of mother-to-child transmission of HIV infections. / Health Studies / (M.A. (Public Health))
93

An investigation of hepatitis B virus in antenatal women tested for human immunodeficiency virus, in the Western Cape Province of South Africa

Maponga, Tongai Gibson 03 1900 (has links)
Thesis (MScMedSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: Hepatitis B virus (HBV) immunisation protocols in much of Africa are based on data from the pre-human immunodeficiency virus (pre-HIV) era that indicated that HBV transmission occurs predominantly horizontally between siblings and play-mates rather than vertically from mother to child. The immunosuppression associated with HIV infection however may release HBV from immune control resulting in higher HBV viral loads, which may increase the risk of perinatal mother to child transmission of HBV. The aim of this study was to determine the prevalence and characteristics of chronic HBV infection in HIV-infected pregnant women compared to HIV-uninfected pregnant women in the Western Cape province of South Africa. Ethical approval was obtained to conduct a retrospective, matched case-control, unlinked anonymous study using residual plasma samples from the 9355 pregnant women included in the Western Cape's 2008 National HIV and Syphilis Antenatal Survey. Samples were tested for HBsAg on the AxSYM (Abbott, Chicago, IL) and confirmed by neutralization. Confirmed HBsAg-positive samples were tested for HBeAg, anti-HBe and anti-HD (Diasorin, Saluggia, Italy) and had HBV viral load and genotyping done. In addition, HBsAg-negative samples were tested for anti-HBc. Samples from 1549 HIV-infected pregnant women were included and matched to the same number of samples from age- and race-matched HIV-uninfected women. Median age of 26 years, parity and education were similar in the two groups. The prevalence of HBsAg was 3.4% for the HIV-infected group and 2.9% for the HIV-uninfected group. HBV DNA loads of greater than 104 IU/ml were detected in 32.1% of HBsAg-positive, HIV/HBV co-infected women, and in 14.3% HBsAg positive, HBV mono-infected women. Among the HIV-infected group 18.9% of HBsAg-positive were HBeAg positive, with a median viral load of 7.93 log10 IU/ml; whilst 15.5% HIV-uninfected women were positive for HBeAg with a median viral load of 6.07 log10 IU/ml. Genotype A was seen in 92.6% of the isolates while 7.4% of the isolates were genotype D. Serum total anti-HBc antibodies that are a marker of past infection were detected in 42.2% of HIV-infected and in 24.1% of HIV-uninfected women that were negative for HBsAg. No positive sample for anti-HD was seen among all HBsAg-positive samples. This data indicates that there is increased exposure to HBV in HIV-infected pregnant women than in HIV-uninfected women and that a greater proportion of HIV-infected pregnant women compared to HBV mono-infected pregnant women may be at increased risk of transmitting HBV to their infants. Further studies are needed to determine the rate of vertical transmission of HBV in the HIV era. / AFRIKAANSE OPSOMMING: Hepatitis B virus (HBV) immunisasie protokolle vir meeste dele van Afrika is gebaseer op data versamel in die era voor MIV. Die data dui aan dat HBV oordrag hoofsaaklik deur horisontale transmissie tussen broers, susters en speelmaats eerder as vertikale transmissie van moeder na kind plaasvind. Die onderdrukking van die immuunstelsel as gevolg van MIV infeksie kan egter lei tot 'n verhoogde risiko van perinatale HBV oordrag van moeder na kind. Die doel van hierdie studie was om die voorkoms en karakter van chroniese HBV infeksie in MIV-positiewe swanger vroue te vergelyk met die van MIV-negatiewe swanger vroue. Etiese goedkeuring is verkry om 'n retrospektiewe, deursnee-, ongekoppelde anonieme studie uit te voer wat gebruik maak van oorblywende plasma monsters van 9355 swanger vroue wat ingesluit is in die Wes-Kaap 2008 Nasionale MIV en Sifilis Voorgeboortelike Opname. Die monsters was getoets vir HBsAg antiliggame (AxSYM, Abbott, Chicago, IL) en bevestig deur neutralisasie toetse. Positiewe monsters was getoets vir HBeAg en anti-HBe (Diasorin, Saluggia, Italië). HBV viruslading en genotipering was ook op HBsAg positiewe monsters gedoen. Die HBsAg negatiewe monsters was getoets vir die teenwoordigheid van anti-HBc. Monsters van 1549 MIV-positiewe swanger vroue was ingesluit in die studie. Dieselfde aantal monsters van MIV-negatiewe vroue, met ooreenstemende ouderdom en etnisiteit, was ingesluit as kontroles. Die gemiddelde ouderdom van albei groepe was 26 jaar. Pariteit en opvoeding was dieselfde in albei groepe. Die voorkomssyfer van HbsAg was 3.4% in die MIV-positiewe groep en 2.8% in die MIV-negatiewe groep. HBV DNS ladings van meer as 104 IU/ml was waargeneem in 32.1% van die MIV-mede-geinfekteerde vroue en in 14.3% van die MIV-negatiewe groep. In die MIV-positiewe groep was 18.9% vroue HBeAg positief, met 'n gemiddelde virale lading van 7.93 log10 IU/ml, terwyl 15.5% MIV-negatiewe vroue positief was vir HBeAg met 'n gemiddelde virale lading van 6.07 log10 IU/ml. In ons studie was 92.6% van die monsters genotipe A en 7.4% genotipe D. Toatale anti-HBc antiliggame, 'n merker van vorige infeksie, was gevind in 42.2% van MIV-mede-geïnfekteerde vroue en 24.1% van MIV-negatiewe vroue wat negatief was vir HBsAg antiliggame. Data van ons studie dui op 'n verhoogde risiko vir vertikale HBV transmissie van MIV-positiewe moeders na hul babas. Verdere studies word benodig om vas te stel of vertikale transmissie van HBV van MIV-positiewe vroue na hul babas plaasvind. / Wellcome Trust / Poliomyelitis Research Foundation
94

Evaluating the process and output indicators for maternal, newborn and child survival in South Africa : a comparative study of PMTCT information systems in KwaZulu-Natal and the Western Cape

Nicol, Edward Fredrick 04 1900 (has links)
Thesis (PhD)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: The prevention of mother-to-child transmission (PMTCT) of HIV is a key maternal and child health intervention in the context of the HIV/AIDS pandemic in South Africa. Accordingly, the PMTCT programme has been incorporated in the District Health Management Information System (DHMIS) that collects monthly facility-based data to support the management of public health services. To date, there has not been a comprehensive evaluation of the PMTCT information system. By comparing the experiences in two health districts, using the Performance of Routine Information System Management (PRISM) framework and tools, this study seeks to evaluate the availability, quality and use of process and output indicators for monitoring PMTCT interventions. A comparative analytical and observational study was undertaken using a multi-method approach which included: a self-administered survey of health information personnel to assess confidence and competence levels for routine health information system (RHIS) tasks, an assessment of the routine PMTCT data for quality, completeness, accuracy, and data use; and a facility survey of RHIS processes and resources. In addition, in-depth interviews with 22 key informants and observations in health facilities were conducted. Data were collected from 57 health facilities in a convenience sample of two health districts, and also from 182 health information personnel in the 57 health facilities, three sub-districts, and two district offices. Descriptive statistics, χ2-test, correlation and multiple regression analyses were conducted using STATA® Version 13. A general inductive approach was also used to analyse the qualitative data, which was used for triangulation. The study revealed considerable data quality concerns for the PMTCT information with an average accuracy between the register and routine monthly report of 51% and between the routine monthly reports and DHMIS database of 84% suggesting that the primary point of departure for accurate transfer of data is during the collation process. The importance of human factors was emphasised by the observation that the average confidence level for performing RHIS-related tasks (69%) was not commensurate with the average competence levels (30%). Education was found to be associated with competence, implying that levels of education may be associated with the level at which RHIS competencies are acquired; and that three years or more of post-matriculation education is necessary. Motivation, on the other hand was not associated Stellenbosch University https://scholar.sun.ac.za iv with competence. The study observed the absence of processes such as data-quality checks and data-analysis in place in facilities. There was a general absence of a culture of information use, as a result of lack of trust in the data, and the inability of programme and facility managers to analyse, interpret and use information. We observed differences in the data accuracy by organisational authority, and multivariate analysis and qualitative information suggested that feedback may be an essential process to ensure quality. Although the PRISM framework has been developed from a multi-disciplinary evidence base, this study has been able to validate some of the internal assumptions but has also found some aspects that were not supported such as motivation and data display. Data collected from a larger number of facilities will be required to investigate this further. Institutional capacity to improve RHIS processes, ensure core competencies for RHIS-related tasks are needed, and in the longer term, measures to tackle problems associated with low pass rates in numeracy subjects among high school learners are needed. Further exploration of the possible factors that may influence data accuracy, such as supervision, training and leadership are needed as well as investigating the relationships between human and institutional agency-related aspects, in particular, how individual actions can bring about changes in institutional routines. Further study is needed to determine how decision for planning and evaluating key programmes such as PMTCT are made, and what informs such decisions if not routine data. / AFRIKAANSE OPSOMMING: In die lig van Suid Afrika se MIV/VIGS-pandemie kan ’n ingryping op gesondheidsvlak ’n belangrike rol speel om moeder-na-kind-oordrag (beter bekend as PMTCT) van MIV te voorkom. ’n Inligtingstelsel vir distriksgesondheidsbestuur – die DHMIS – was ontwerp vir die invordering van maandelikse fasiliteitsdata, wat gebruik kan word om die bestuur van openbare gesondheidsdienste en -programme te ondersteun. Die inligtingstelsel self was nog nie omvattend evalueer nie. Hierdie studie het die ervarings van twee gesondheidsdistrikte vergelyk met behulp van die PRISM- (Performance of Routine Information System) raamwerk en -instrumente. Derhalwe het hierdie studie die beskikbaarheid, gehalte en gebruik van proses- en uitsetaanwysers probeer bepaal om die PMTCT-ingrypings te monitor. ’n Vergelykende analitiese en waarnemingstudie is onderneem met behulp van ’n veelvuldige benadering. Die verskillende metodes het ’n selfopname onder gesondheidsinligtingspersoneel ingesluit om hul selfvertroue en bevoegdheid in roetinegesondheidsinligtingstelsel (RHIS)-take te evalueer. Daar was ook ’n assessering van die PMTCT-roetinedata om datagehalte, -volledigheid, -akkuraatheid en -gebruik te beoordeel.’n Fasiliteitsopname oor RHIS-prosesse en –hulpbronne was ook gedoen. Ander navorsingsmetodes het diepte-onderhoude met 22 sleutelpersone ingesluit, sowel as waarnemings in gesondheidsfasiliteite. Data is van 182 gesondheidsinligtingpersoneel van die 57 gesondheidsfasiliteite in ’n geriefsteekproef van twee gesondheidsdistrikte ingesamel. Deskriptiewe statistiek, χ2-toetsing, korrelasie en veelvoudige regressie is met behulp van STATA® weergawe 13 ontleed. ʼn Algemene induktiewe benadering is ook gevolg om die kwalitatiewe data te ontleed. Die studie toon dat menslike faktore ’n impak op datagehalte en -inligting kan hê, met ’n gemiddelde akkuraatheidsyfer van 51% van beide die register en roetine maandelikse verslae. Die akkuraatheid van die maandelikse verslae en RHIS databasis is 84%, wat aandui dat akkuraatheid slegs toegepas word indien inligting uit die staanspoor korrek aangeteken word. Die impak van menslike hulpbronafaktore was beklemtoon toe daar bevind was dat hoewel 69% van RHIS-dataverwerkers vertroue getoon het in die gebruik van RHIS-verwante take, slegs 30% wel bevoeg was om die werk te doen. Opvoeding was grootliks geassosieer met bevoegdheid, wat moontlik voorstel dat sekere vlakke van opvoeding benodig word vir spesifieke RHIS-bevoegdhede. Minsten drie jaar tersiêre opleiding word aanbebeel. Motivering was nie met Stellenbosch University https://scholar.sun.ac.za vi bevoegdheid geklassifeer nie. Die studie het bevind dat daar te min aandag aan datagehalte en –analise gegee word in fasiliteite. Oor die algemeen was daar nie ’n ordentlike kultuur van inligtinggebruik nie, a.g.v. die feit dat daar nie vertroue in die data was nie. Terselftertyd was program- en fasiliteitbestuurders nie bevoeg om inligting te analiseer en ontleed nie. Ons het verskille in die akkuraatheid van data opgetel wat deur organisasie-hoofde gedoen was. Meervoudige analise en kwalitatiewe informasie stel voor dat terugvoering ’n belangrike deel van die proses moet wees om kwaliteit te verseker. Hoewel die PRISM-raamwerk saamgestel was uit ’n multi-dissiplinêre bewyslewering, kon hierdie studie sommige van die interne voorneme valideer, maar daar was aspekte wat nie gestaaf kon word nie. Inligting van ’n groter aantal fasiliteite sal benodig word om verder hierna ondersoek in te stel. Institusionele kapasiteit word benodig om RHIS-prosesses te verbeter en basiese vaardighede vir RHIS-verwante take te verseker. Op langtermynvlak moet daar ook gekyk word na probleme wat lei tot laë slaagsyfers in syfervaardighede in hoërskoolleerders. Verdere ondersoek moet ingestel word om vas te stel watter faktore moontlik akkurate data teweeg kan bring. Dit sluit toesig, opleiding en leierskap, asook die verhoudings tussen menslike en agentskap-verwante aspekte in. Die feit dat optrede op individuele vlak veranderings in institusionele roetines kan aanbring, moet spesifiek na gekyk word. Verdere studies kan help om vas te stel hoe besluite vir beplanning en evaluaring vir hoofprogramme soos PMTCT gemaak word – asook hoe die besluite gemaak word indien hulle nie roetine voorafgaan nie.
95

Effective prevention of mother-to-child transmission of HIV at Oshakati District Health Centre in the Republic of Namibia

Shoopala, Naemi Ndahambelela 02 1900 (has links)
The aim of this study was to assess the extent on how effective was the prevention of mother-to-child transmission of Human Immunodeficiency Virus (HIV) infection at Oshakati District Health Centre. Explanatory survey was used to conduct the research. A total of 160 nurses experienced in prevention of mother-to-child transmission and women who attended antenatal care and post natal care services participated in the study. Respondents expressed unsatisfactory with the promoting involvement of male partners, high quality voluntary counselling and testing services, couple counselling and testing, integration of Highly Active Antiretroviral Therapy services, administration of short course of Zidovudine to pregnant mothers and the provision of antiretroviral drugs to infants. Therefore, promoting involvement of male partners, couple counselling and testing, administration of short course of Zidovudine to pregnant mothers and educating women about exclusive breastfeeding prior to delivery are some of recommendations for effective prevention of mother-to-child transmission of HIV infections. / Health Studies / M.A. (Public Health)
96

Knowledge of women attending antenatal clinics on transmission of HIV through breast-feeding in Gaborone, Botswana

Kasinja, Faides Tsalani 30 June 2006 (has links)
Breast-feeding by Human Immunodeficiency Virus (HIV) positive mothers poses a risk of transmitting HIV infection from the mother to the baby. This study attempted to describe and explore the knowledge of antenatal women in Gaborone, Botswana on the transmission of HIV through breast-feeding. The research results, obtained from interview schedules, revealed that the respondents had: a greater knowledge of transmission of HIV in adults than mother-to-child-transmission (MTCT); a moderate understanding of infant feeding methods; poor understanding of the risk of HIV transmission through different infant feeding methods and feelings that infant feeding method reveals ones HIV status, which indicate stigma and discrimination. The study findings may assist health care providers to intensify educational programmes and counselling in the antenatal clinics and communities to reduce MTCT. / Health Studies / M. A. (Health Studies)
97

An evaluation of postnatal care rendered to HIV positive women and their infants

Dlamini, Bongani Robert 01 February 2013 (has links)
The purpose of this study was to evaluate care rendered to HIV positive women and their infants during the first six weeks of postpartum. Quantitative, descriptive, cross sectional and analytic study was conducted to investigate postnatal care services provided to HIV positive mothers. Data collection was done using structured questionnaires. 372 respondents participated in the study. Descriptive data analysis was used; Epi info version 3.5.2 software was used. The study highlighted that the quality of PNC was compromised, in all levels including the critical immediate postnatal care, 3-14 days and 6 weeks postnatal care services. All health facilities that were involved in the study had the basic resources to render quality postnatal care. Negative attitudes of staff and long waiting time (16.7%), were the most deterrents to postnatal care. / Health Studies / M.A. (Health Studies)
98

Perceptions of midwives and pregnant women of the prevention of mother-to-child transmission of HIV programme at the ante-natal care unit and maternity ward at the Johan Heyns community health centre in tne Sedibeng District, Gauteng

Thithi, Potetsa Elizabeth 02 1900 (has links)
The study reports on the perceptions of the midwives and pregnant women of the PMTCT of HIV programme at the antenatal care and maternity ward at the Johan Heyns Community Health Centre. A qualitative approach was adopted to conduct the study. Purposive sampling was used to select participants and was informed by social behavioural theories. Data was collected using interviews and analysed using thematic categorisation. The findings show that at the first PMTCT encounter participants had little to no knowledge of the PMTCT programme, generally displayed a lack of interest, experienced emotional distress, and fear at the thought of having to disclosing their HIV-positive status to their partners/family and had certain trepidations about participating in the PMTCT programme. The participants’ perception on their roles was that their roles were interlinked, midwife needs the recipients (pregnant woman) and pregnant woman needs the provider (midwife) therefore one cannot do PMTCT without the other. The study recommends that the capacity building of pregnant women be optimised, that PMTCT awareness campaigns for women of childbearing age should be a priority and PMTCT skills to be prerequisite for midwives deployed to ANC clinics and maternity ward units. / Health Studies / M. A. (Social Behaviour Studies in HIV/AIDS)
99

Guidelines for promoting supplementary infan feeding techniques among HIV-positive mothers

Chaponda, Armelia Stephanie 05 March 2013 (has links)
Vertical transmission of HIV is still a growing concern in South Africa. Breastfed infants are still at risk as HIV is present in breast milk, leaving HIV-positive mothers unsure of the best feeding option for their infants. However, there are various infant feeding techniques that HIV-positive mothers can use to supplement breastfeeding and flash-heat is one of them. Flash-heat is heat treating expressed breast milk to deactivate HIV for infant feeding. This study explored the possibility of HIV-positive mothers to practice flash-heating method for their infants exclusively for four months as a strategy to prevent vertical transmission of HIV. A descriptive, explorative and contextual design using a mixed method was used to obtain data from mothers in a post natal ward at Tembisa hospital. The mixed method used was useful in identifying the number of HIV-positive mothers who would adopt the flash-heat technique, the characteristics of mothers whom the technique could be promoted to, the factors that influence/affect the choice of infant feeding for these mothers, as well as their feelings associated with the feeding technique. Most (74%) mothers had a positive response to the flash-heat technique compared to 10% who were uncertain. They believed that heat treating their breast milk would result in their infants being HIV-free. In addition they believed that this method was cheaper than formula feeding and expressed positive feelings about touching their breast milk while expressing with no adverse feelings of expressing into a glass jar. Furthermore, findings of this study indicated that HIV-positive mothers in a public health facility would adopt flash-heat as an alternative infant feeding method. Thus practical guidelines to promote this feeding method were proposed. The proposed draft guidelines which promote the use of the flash-heat infant feeding method for HIV-positive mothers in public sector facilities will be communicated to relevant authorities such as the National Department of Health. These guidelines support the new policy shift to exclusive breastfeeding as a child survival strategy in South Africa. / Health Studies / D.Litt. et Phil. (Health Studies)
100

The prevalence of Hepatitis B virus infection in an HIV-exposed paediatric cohort from the Western Cape, South Africa

Chotun, Bibi Nafiisah 12 1900 (has links)
Thesis (MScMedSc))--Stellenbosch University, 2012. / Includes bibliography / ENGLISH ABSTRACT: Despite the availability of Hepatitis B virus (HBV) vaccination for over three decades, this infection remains a major public health problem. Whilst the WHO recommends giving a birth dose of the vaccine, in South Africa, routine infant HBV vaccination commences at six weeks of age. This schedule is based on data from the pre-HIV era which showed transmission occurred via the horizontal, rather than the vertical route. In the era of HIV however, maternal HIV co-infection may release HBV from immune control, resulting in higher HBV loads and increasing the risk of vertical transmission. The aim of this study was to determine the prevalence and character of HBV infection in HIV-exposed infected and uninfected infants. Residual plasma samples from routine HIV nucleic acid testing of 1000 HIV-exposed infants aged between 0 and 18 months from the Western Cape were tested. Samples were tested for HBsAg by ELISA (Murex HBsAg Version 3) and confirmed by neutralisation. HBV DNA was quantified using an in-house real-time PCR assay. Infants with HBsAg positive samples were followed up and a blood sample was collected from mother and child. Those HBsAg positive samples were tested for HBeAg/antiHBe (Diasorin) and HBsAg negative samples were tested for antiHBs. HBV DNA was quantified. The surface gene was sequenced and the HBV genotype determined by phylogenetic analysis using HepSEQ (www.hepseq.org.uk). Whole genome sequencing was also performed. Of 1000 samples tested, four samples were positive for HBsAg and/or HBV DNA, indicating a prevalence of HBV transmission of 0.4%. At follow-up, two of three infected infants were positive for HBsAg, with HBV viral loads of greater than 108 IU/ml. The third infant was found to have cleared his infection and the fourth child was lost to follow up. These infected infants had all received HBV vaccination. All four mothers were HBeAg positive. Sequencing analysis showed the HBV strains from the two infants and four mothers belonged to subgenotype A1. The two mother-child paired sequences were identical. The data from this study shows that vertical transmission of HBV infection in HIV-exposed infants from the Western Cape is occurring, despite vaccination. Data from the Western Cape, showing an HBV prevalence of 3.4% in HIV-infected pregnant women, and those presented here suggest a vertical transmission rate of HBV of 12%. This is despite the widespread use of tenofovir and lamivudine in HIV-infected women with low CD4 counts. This study provides data supporting calls to bring HBV vaccination closer to the time of birth. Further work is urgently needed to confirm these findings and to determine the rates of transmission in HIV-unexposed infants. / AFRIKAANSE OPSOMMING: Ten spyte van die beskikbaarheid van die Hepatitis B virus (HBV) inenting vir meer as drie dekades, hierdie infeksie bly 'n groot openbare gesondheid probleem. Terwyl die WGO aan beveel dat'n geboorte dosis van die entstof, in Suid-Afrika, roetine baba HBV inenting op die ouderdom van ses weke gegee word. Hierdie skedule is gebaseer op data van die pre-MIV era wat getoon het dat die oordrag plaasgevind het via die horisontale, eerder as die vertikale roete. In die era van MIV egter, moeder MIV ko-infeksie kan HBV vrylaat van immuun beheer, wat lei in hoër HBV vlakke en die verhoging van die risiko van vertikale oordrag. Die doel van hierdie studie was om die voorkoms en karakter van die HBV infeksie in MIV-besmette en onbesmette babas te bepaal. Residuele plasma monsters van roetine-MIV-nukleïensuur toetse van 'n 1000 MIV-blootgestelde babas tussen die ouderdomme van 0 en 18 maande van die Wes-Kaap was getoets. Monsters was getoets vir HBsAg deur ELISA (Murex HBsAg Version 3) en bevestig deur neutralisering. HBV DNA is gekwantifiseer deur gebruik te maak van 'n in-huis real-time PCR assay. Babas met HBsAg positiewe monsters was opgevolg en 'n bloedmonster is versamel van moeder en kind. Die HBsAg positiewe monsters was getoets vir HBeAg/antiHBe (Diasorin) en HBsAg negatiewe monsters was getoets vir antiHBs. HBV DNA was gekwantifiseer. Die oppervlak gene volgorde en genotipes was bepaal deur filogenetiese analise met behulp van HepSEQ (www.hepseq.org.uk). Die hele genoom-volgordebepaling was ook uitgevoer. Van die 1000 monsters wat getoets was, was vier monsters positief vir HBsAg en of HBV DNA, dit dui op 'n voorkoms van HBV oordrag van 0.4%. By op volg, twee van die drie besmette babas was positief vir HBsAg, met HBV virale vlakke van groter as 108 IE/ml. Die derde baba was gevind dat sy infeksie opgeklaar het en die vierde kind was verlore as gevolg van op volg. Hierdie besmette babas het almal HBV inenting ontvang. Al vier moeders was HBeAg positief. Volgordebepaling analise het getoon die HBV stamme van die twee babas en vier moeders behoort aan subgenotype A1. Die twee moeder-kind gepaarde rye was homoloë. Die data van hierdie studie toon dat die vertikale oordrag van HBV infeksie in MIV-blootgestelde babas van die Wes-Kaap vind plaas, ten spyte van inenting. Data van die Wes-Kaap, wat 'n HBV voorkoms van 3.4% in MIV-besmette swanger vroue, en dié wat hier aangebied is dui op 'n vertikale oordrag koers van 12% van die HBV. Dit is ten spyte van die wydverspreide gebruik van tenofovir en lamivudine in MIV-geïnfekteerde vroue met 'n lae CD4-telling. Hierdie studie bied data wat ondersteunende oproepe van HBV inenting nader aan die tyd van die geboorte bring. Verdere werk is dringend nodig om die bevindinge te bevestig en die pryse van die oordrag in MIV-blootgestelde babas te bepaal. / National Health Laboratory Service Research Trust / Poliomyelitis Research Foundation (PRF) / Harry Crossley Foundation / Stellenbosch University

Page generated in 0.0897 seconds