CIDRZ Research

Permanent URI for this communityhttps://pubs.cidrz.org/handle/123456789/1

Welcome to the CIDRZ Research Repository

The CIDRZ Research Repository serves as an open-access archive for peer-reviewed publications, conference papers, and other scholarly outputs from CIDRZ researchers. Our goal is to promote the dissemination of knowledge and support evidence-based public health initiatives.

News

New Research Publications Added

We have recently added new publications on HIV prevention, maternal health, and epidemiology. Browse the latest research in our repository.

Open Access Week 2025

Join us in celebrating Open Access Week! Learn how open-access publishing enhances research visibility and impact.

Browse

Search Results

Now showing 1 - 10 of 95
  • Thumbnail Image
    Item
    Perceptions toward HIV, HIV screening, and the use of antiretroviral medications: a survey of maternity-based health care providers in Zambia.
    (2004-Oct) Chi BH; Chansa K; Gardner MO; Sangi-Haghpeykar H; Goldenberg RL; Sinkala M; Muchimba M; Stringer JS; Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, Texas, USA. Bchi@cidrz.org; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)
    Mother-to-child transmission of HIV (MTCT) is a major contributor to Zambia's HIV burden. Based on our experience in Zambia, we felt that provider perceptions, knowledge base, and practice patterns toward HIV-positive mothers may pose as significant obstacles to preventing MTCT. Two hundred and twenty-five health care providers throughout Zambia were surveyed in 2002. Providers reported widespread stigma associated with HIV. Physicians (OR = 1.9), providers with research affiliations (OR = 2.3), and those located in Lusaka (OR = 9.0) were more likely to offer HIV testing. Only 30% routinely prescribed antiretroviral treatment (ART) to reduce MTCT. Practitioners from district facilities, those from Lusaka, and those employed at research facilities were more likely to prescribe ART routinely (OR = 2.8, 10.1 and 3.4 respectively). Among those never prescribing ART, most cited a lack of availability (83%). Our results highlight the need for further provider education, critical appraisal of the current system for HIV testing, and widespread distribution of ART.
  • Thumbnail Image
    Item
    Timing of maternal and neonatal dosing of nevirapine and the risk of mother-to-child transmission of HIV-1: HIVNET 024.
    (2005-Nov-04) Chi BH; Wang L; Read JS; Sheriff M; Fiscus S; Brown ER; Taha TE; Valentine M; Goldenberg R; University of Alabama at Birmingham, Department of Obstetrics & Gynecology, Birmingham, Alabama, USA. bchi@cidrz.org; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)
    OBJECTIVE: Despite a growing emphasis worldwide on complex and potent antiretroviral drug regimens for the prevention of mother-to-child transmission of HIV-1 (MTCT), two-dose nevirapine (NVP) prophylaxis remains an important choice in many settings. We analyzed data from a multicenter clinical trial to determine whether timing of maternal or infant NVP was associated with MTCT between delivery and 6 weeks of age (intrapartum/early postnatal transmission; I/EP). METHODS: HIVNET 024 was a placebo-controlled, double-blind trial of empiric antibiotics to reduce chorioamnionitis-associated MTCT. This secondary analysis used data collected in the original randomized trial. Enrolled women were instructed to self-administer NVP at labor onset; infants were to receive a dose within 72 h of birth. RESULTS: Data regarding 1491 mother-infant pairs were analyzed. The overall I/EP HIV-1 transmission rate was 8.1% at 6 weeks. Almost all women (93%) ingested NVP within 24 h of delivery; 90% of infants were given NVP within 48 h after delivery. Variations in mother or infant dose timing did not influence transmission rates, even when the combined pattern of both was taken into account through multivariate analysis. In the subset of women ingesting NVP or= 4 h). CONCLUSION: Variations in the timing of maternal and infant NVP doses (within reasonable proximity to delivery) do not appear to affect the risk of MTCT.
  • Thumbnail Image
    Item
    Cost and enrollment implications of targeting different source population for an HIV treatment program.
    (2005-Nov-01) Chi BH; Fusco H; Sinkala M; Goldenberg RL; Stringer JS; Centre for Infectious Disease Research in Zambia, Lusaka, Zambia. bchi@uab.edu; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)
    BACKGROUND: Rapid scale-up of antiretroviral therapy (ART) is a worldwide priority, and ambitious targets for numbers on ART have been set. Antenatal clinics (ANCs) and tuberculosis (TB) clinics have been targeted as entry points into HIV care. METHODS: We developed a conditional probability model to evaluate the effects of ANC and TB clinic populations on ART program enrollment. RESULTS: To start 1 individual on ART, 3 TB patients have to be screened at a crude program cost of 36 US dollars per patient initiated on therapy. By contrast, 48 ANC patients have to be screened at a cost of US 214 US dollars per patient on therapy. In an incremental analysis in which ANC HIV testing was borne by a program to prevent mother-to-child transmission, recruitment efficiency increased (8 screened per patient starting ART) and cost decreased (114 US dollars per patient on therapy). Absolute numbers starting ART, however, remained fixed. If all 60,000 ANC patients seen yearly in the Lusaka District were screened, 1247 would start ART. Approaching the district's 35,000 annual TB patients would generate 11,947 patients on ART. CONCLUSION: In areas with high HIV prevalence, targeting chronically ill populations for HIV treatment may have significant short-term benefits in cost savings and recruitment efficiency.
  • Thumbnail Image
    Item
    HIVCorps: using volunteers to rapidly expand HIV health services across Zambia.
    (2006-May) Chi BH; Fusco H; Goma FM; Zulu I; Simmers E; Stringer JS; Centre for Infectious Disease Research in Zambia, Lusaka, Zambia. bchi@cidrz.org; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)
    In 2004, we created HIVCorps, an international volunteer program to involve pre-medical, medical, and public health students in the scale-up of HIV care and prevention services in Zambia. In our first year, we used 27 American and Zambian volunteers to assist with the administrative and logistical aspects of program implementation. Ten volunteers were based in the capital Lusaka; the remaining 17 were stationed across five rural districts. Supervision was provided by local health care providers, district officials, and hospital administrators. In our setting, the use of volunteers has proven feasible and effective for program support. Depending on a program's immediate needs, use of many basic field personnel may be more beneficial than employment of one to two trained clinicians. Formal volunteer programs like HIVCorps should be developed alongside initiatives focused on deploying more specialized, experienced healthcare workers aboard.
  • Thumbnail Image
    Item
    Field performance of a thin-layer chromatography assay for detection of nevirapine in umbilical cord blood.
    (2006) Chi BH; Lee A; Acosta EP; Westerman LE; Sinkala M; Stringer JS; Centre for Infectious Disease Research in Zambia, Lusaka, Zambia. bchi@cidrz.org; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)
    PURPOSE: Although cord blood surveillance can measure the effectiveness of nevirapine (NVP)-based programs for the prevention of mother-to-child HIV transmission (PMTCT), it requires the ability to detect nevirapine in plasma. At present, the only validated method is high-performance liquid chromatography (HPLC), a technique poorly suited for most resource-constrained settings. METHOD: We evaluated the field performance for a simple and inexpensive thin-layer chromatography (TLC) assay for NVP detection. We developed a conditional probability model to compare 2 testing algorithms: HPLC alone, and TLC screening followed by HPLC confirmation of negative results. RESULTS: When compared to HPLC, sensitivity of TLC was 0.67 (95% confidence interval [CI] 0.49-0.84) and specificity was 0.84 (95% CI 0.69-0.95). In this sample - where overall NVP coverage was 49% - positive predictive value was 0.80 and negative predictive value was 0.72. At baseline with population NVP coverage of 33%, cost per specimen was lower in the TLC-HPLC testing algorithm (40 dollars vs. 50 dollars), and the proportion of false results was acceptable (11%). As population NVP coverage increased, cost-efficiency improved and error rate dropped substantially. CONCLUSION: TLC is reasonably sensitive and specific for NVP detection. A 2-step testing algorithm incorporating TLC and HPLC provides cost-efficiency at little expense to test performance.
  • Thumbnail Image
    Item
    Early clinical and immune response to NNRTI-based antiretroviral therapy among women with prior exposure to single-dose nevirapine.
    (2007-May-11) Chi BH; Sinkala M; Stringer EM; Cantrell RA; Mtonga V; Bulterys M; Zulu I; Kankasa C; Wilfert C; Weidle PJ; Vermund SH; Stringer JS; Centre for Infectious Disease Research in Zambia, Zambia. bchi@cidrz.org; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)
    OBJECTIVE: To determine whether prior exposure to single-dose nevirapine (NVP) for prevention of mother-to-child HIV transmission (PMTCT) is associated with attenuated CD4 cell response, death, or clinical treatment failure in women starting antiretroviral therapy (ART) containing non-nucleoside reverse transcriptase inhibitors (NNRTI). METHODS: Open cohort evaluation of outcomes for women in program sites across Zambia. HIV treatment was provided according to Zambian/World Health Organization guidelines. RESULTS: Peripartum NVP exposure status was known for 6740 women initiating NNRTI-containing ART, of whom 751 (11%) reported prior use of NVP for PMTCT. There was no significant difference in mean CD4 cell change between those exposed or unexposed to NVP at 6 (+202 versus +182 cells/microl; P = 0.20) or 12 (+201 versus +211 cells/microl; P = 0.60) months. Multivariable analyses showed no significant differences in mortality [adjusted hazard ratio (HR), 1.2; 95% confidence interval (CI), 0.8-1.8] or clinical treatment failure (adjusted HR, 1.1; 95% CI, 0.8-1.5). Comparison of recent NVP exposure with remote exposure suggested a less favorable CD4 cell response at 6 (+150 versus +219 cells/microl; P = 0.06) and 12 (+149 versus +215 cells/microl; P = 0.39) months. Women with recent NVP exposure also had a trend towards elevated risk for clinical treatment failure (adjusted HR, 1.6; 95% CI, 0.9-2.7). CONCLUSION: Exposure to maternal single-dose NVP was not associated with substantially different short-term treatment outcomes. However, evidence was suggestive that exposure within 6 months of ART initiation may be a risk factor for poor treatment outcomes, highlighting the importance of ART screening and initiation early in pregnancy.
  • Thumbnail Image
    Item
    A randomized trial of the intrauterine contraceptive device vs hormonal contraception in women who are infected with the human immunodeficiency virus.
    (2007-Aug) Stringer EM; Kaseba C; Levy J; Sinkala M; Goldenberg RL; Chi BH; Matongo I; Vermund SH; Mwanahamuntu M; Stringer JS; Centre for Infectious Disease Research in Zambia, Lusaka, Zambia. eli@uab.edu; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)
    OBJECTIVE: The purpose of this study was to determine whether the intrauterine contraceptive device (IUD) is effective and safe among women who are infected with the human immunodeficiency virus (HIV). STUDY DESIGN: We randomly assigned 599 postpartum, HIV-infected women in Zambia to receive either a copper IUD or hormonal contraception and followed them for at least 2 years. RESULTS: Women who were assigned randomly to hormonal contraception were more likely to become pregnant than those who were assigned randomly to receive an IUD (rate, 4.6/100 vs 2.0/100 woman-years; hazards ratio, 2.4; 95% CI, 1.3-4.7). One woman who was assigned to the IUD experienced pelvic inflammatory disease (crude rate, 0.16/100 woman-years; 95% CI, 0.004-868); there was no pelvic inflammatory disease among those women who were assigned to hormonal contraception. Clinical disease progression (death or CD4+ lymphocyte count dropping below 200 cells/microL) was more common in women who were allocated to hormonal contraception (13.2/100 woman-years) than in women who were allocated to the IUD (8.6/100 woman-years; hazard ratio, 1.5; 95% CI, 1.04-2.1). CONCLUSION: The IUD is effective and safe in HIV-infected women. The unexpected observation that hormonal contraception was associated with more rapid HIV disease progression requires urgent further study.
  • Thumbnail Image
    Item
    Use of traditional medicine among pregnant women in Lusaka, Zambia.
    (2007) Banda Y; Chapman V; Goldenberg RL; Stringer JS; Culhane JF; Sinkala M; Vermund SH; Chi BH; University of Zambia School of Medicine, Lusaka, Zambia. yolan.banda@cidrz.org; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)
    OBJECTIVE: We studied the prevalence of and predictors for traditional medicine use among pregnant women seeking care in the Lusaka, Zambia public health system. SUBJECTS: We surveyed 1128 pregnant women enrolled in a clinical trial of perinatal human immunodeficiency virus (HIV) prevention strategies at two district delivery centers. OUTCOME MEASURES: Postpartum questionnaires were administered to determine demographic characteristics, behavioral characteristics, HIV knowledge, and prior use of traditional medicines. RESULTS: Of the 1128 women enrolled, 335 (30%) reported visiting a traditional healer in the past; 237 (21%) reported using a traditional healer during the current pregnancy. Overall, 54% believed that admitting to a visit to a traditional healer would result in worse medical care. When women who had used traditional medicines were compared to those who had not, no demographic differences were noted. However, women who reported use of traditional medicine were more likely to drink alcohol during pregnancy, have >or=2 sex partners, engage in "dry sex," initiate sex with their partner, report a previously treated sexually transmitted disease, and use contraception (all p < 0.01). HIV-infected women who reported using traditional healers were also less likely to adhere to a proven medical regimen to reduce HIV transmission to their infant (25% versus 50%, p = 0.048). CONCLUSIONS: Use of traditional medicine during pregnancy is common, stigmatized, and may be associated with nonadherence to antiretroviral regimens. Health care providers must open lines of communication with traditional healers and with pregnant women themselves to maximize program success.
  • Thumbnail Image
    Item
    Clinical outcomes and CD4 cell response in children receiving antiretroviral therapy at primary health care facilities in Zambia.
    (2007-Oct-24) Bolton-Moore C; Mubiana-Mbewe M; Cantrell RA; Chintu N; Stringer EM; Chi BH; Sinkala M; Kankasa C; Wilson CM; Wilfert CM; Mwango A; Levy J; Abrams EJ; Bulterys M; Stringer JS; Centre for Infectious Disease Research in Zambia, Lusaka.; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)
    CONTEXT: The Zambian Ministry of Health provides pediatric antiretroviral therapy (ART) at primary care clinics in Lusaka, where, despite scale-up of perinatal prevention efforts, many children are already infected with the human immunodeficiency virus (HIV). OBJECTIVE: To report early clinical and immunologic outcomes of children enrolled in the pediatric treatment program. DESIGN, SETTING, AND PATIENTS: Open cohort assessment using routinely collected clinical and outcome data from an electronic medical record system in use at 18 government primary health facilities in Lusaka, Zambia. Care was provided primarily by nurses and clinical officers ("physician extenders" akin to physician assistants in the United States). Patients were children (<16 years of age) presenting for HIV care between May 1, 2004, and June 29, 2007. INTERVENTION: Three-drug ART (zidovudine or stavudine plus lamivudine plus nevirapine or efavirenz) for children who met national treatment criteria. MAIN OUTCOME MEASURES: Survival, weight gain, CD4 cell count, and hemoglobin response. RESULTS: After enrollment of 4975 children into HIV care, 2938 (59.1%) started ART. Of those initiating ART, the median age was 81 months (interquartile range, 36-125), 1531 (52.1%) were female, and 2087 (72.4%) with World Health Organization stage information were in stage III or IV. At the time of analysis, 158 children (5.4%) had withdrawn from care and 382 (13.0%) were at least 30 days late for follow-up. Of the remaining 2398 children receiving ART, 198 (8.3%) died over 3018 child-years of follow-up (mortality rate, 6.6 deaths per 100 child-years; 95% confidence interval [CI], 5.7-7.5); of these deaths, 112 (56.6%) occurred within 90 days of therapy initiation (early mortality rate, 17.4/100 child-years; post-90-day mortality rate, 2.9/100 child-years). Mortality was associated with CD4 cell depletion, lower weight-for-age, younger age, and anemia in multivariate analysis. The mean CD4 cell percentage at ART initiation among the 1561 children who had at least 1 repeat measurement was 12.9% (95% CI, 12.5%-13.3%) and increased to 23.7% (95% CI, 23.1%-24.3%) at 6 months, 27.0% (95% CI, 26.3%-27.6%) at 12 months, 28.0% (95% CI, 27.2%-28.8%) at 18 months, and 28.4% (95% CI, 27.4%-29.4%) at 24 months. CONCLUSIONS: Care provided by clinicians such as nurses and clinical officers can result in good outcomes for HIV-infected children in primary health care settings in sub-Saharan Africa. Mortality during the first 90 days of therapy is high, pointing to a need for earlier intervention.
  • Thumbnail Image
    Item
    Predictors of stillbirth in sub-saharan Africa.
    (2007-Nov) Chi BH; Wang L; Read JS; Taha TE; Sinkala M; Brown ER; Valentine M; Martinson F; Goldenberg RL; Centre for Infectious Disease Research in Zambia, Lusaka, Zambia. bchi@cidrz.org; CIDRZ; Centre for Infectious Disease Research in Zambia (CIDRZ)
    OBJECTIVE: To describe the incidence and predictors of stillbirth in a predominantly human immunodeficiency virus (HIV)-infected African cohort. METHODS: Human Immunodeficiency Virus (HIV) Prevention Trials Network (HPTN) 024 was a randomized controlled trial of empiric antibiotics to reduce chorioamnionitis-related perinatal HIV transmission. A proportion of HIV-uninfected individuals were enrolled to reduce community-based stigma surrounding the trial. For this analysis, only women who gave birth to singleton infants were included. RESULTS: Of 2,659 women enrolled, 2,434 (92%) mother- child pairs met inclusion criteria. Of these, 2,099 (86%) infants were born to HIV-infected women, and 335 (14%) were born to HIV-uninfected women. The overall stillbirth rate was 32.9 per 1,000 deliveries (95% confidence interval [CI] 26.1-40.7). In univariable analyses, predictors for stillbirth included previous stillbirth (odds ratio [OR] 2.3, 95% CI 1.2-4.3), antenatal hemorrhage (OR 14.4, 95% CI 4.3-47.9), clinical chorioamnionitis (OR 20.9, 95% CI 5.1-86.2), and marked polymorphonuclear infiltration on placental histology (OR 2.9, 95% CI 1.7-5.2). When compared with pregnancies longer than 37 weeks, those at 34-37 weeks (OR 1.7, 95% CI 0.8-3.4) and those at less than 34 weeks (OR 22.8, 95% CI 13.6-38.2) appeared more likely to result in stillborn delivery. Human immunodeficiency virus infection was not associated with a greater risk for stillbirth in either univariable (OR 1.5, 95% CI 0.7-3.0) or multivariable (adjusted OR 1.11, 95% CI 0.38-3.26) analysis. Among HIV-infected women, however, decreasing CD4 cell count was inversely related to stillbirth risk (P=.009). CONCLUSION: In this large cohort, HIV infection was not associated with increased stillbirth risk. Further work is needed to elucidate the relationship between chorioamnionitis and stillbirth in African populations. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00021671 LEVEL OF EVIDENCE: II.

All research publications in this repository are the property of the Centre for Infectious Disease Research in Zambia (CIDRZ). Where applicable, content is licensed under a Creative Commons Attribution 4.0 License.

If you wish to reuse or cite materials from this repository, please ensure proper attribution and check the publisher's copyright policies.