King C.C.,Centers for Disease Control and Prevention |
Kourtis A.P.,Centers for Disease Control and Prevention |
Persaud D.,Johns Hopkins University |
Ziemniak C.,Johns Hopkins University |
And 5 more authors.
AIDS | Year: 2015
Objective: The objective of this study is to determine whether detection of HIV infection was delayed in infants exposed to antiretroviral prophylaxis to prevent HIV transmission during breastfeeding. Design: The Breastfeeding, Antiretrovirals and Nutrition (BAN) study was a randomized trial of 2369 mother-infant pairs conducted from 2004 to 2010. In addition to an intrapartum regimen, all mother-infant pairs were randomly assigned to three antiretroviral intervention arms during 28 weeks of breastfeeding: no further antiretroviral prophylaxis (control arm); infant-daily nevirapine (nevirapine arm); and maternal zidovudine, lamivudine and either nevirapine, nelfinavir or lopinavir-ritonavir (maternal arm). After breastfeeding cessation counselling and stopping the antiretroviral interventions by 28 weeks, 28 infant HIV infections occurred. Methods: To determine whether these infections occurred during the breastfeeding and antiretroviral intervention phase but had delayed detection on the antiretroviral arms, we performed ultrasensitive (droplet digital PCR) HIV testing on infants with stored peripheral blood mononuclear cell (PBMC) specimens at 24 weeks (n=9). Results: Of the nine infants, all three on the infant nevirapine arm had detectable HIV DNA at 24 weeks, compared with two of four on the maternal antiretroviral arm and one of two on the control arm. For infants with detectable HIV at 24 weeks, the median delay in detection between the ultrasensitive and standard assays was 18.3 weeks for the nevirapine arm, 15.4 weeks for the maternal arm and 9.4 weeks for the control arm. Conclusion: The prolonged inability to detect HIV with standard assays in the context of postnatal antiretroviral prophylaxis suggests that early antiretrovirals may restrict HIV replication sufficiently to lead to missed diagnosis among infected infants. Therefore, repeat virologic testing is warranted beyond the WHO-recommended point of testing at 6 weeks after breastfeeding cessation. © 2015 Wolters Kluwer Health, Inc. All rights reserved. Source
Pettifor A.,University of North Carolina at Chapel Hill |
Pettifor A.,University of Witwatersrand |
Macphail C.,University of Witwatersrand |
Corneli A.,Family Health International |
And 7 more authors.
AIDS and Behavior | Year: 2011
Understanding sexual behavior following diagnosis of acute HIV infection (AHI) is key to developing prevention programs targeting individuals diagnosed with AHI. We conducted separate qualitative and quantitative interviews with individuals newly diagnosed (n = 19) with AHI at 1-, 4- and 12-weeks post-diagnosis and one qualitative interview with individuals who had previously been diagnosed with AHI (n = 18) in Lilongwe, Malawi and Johannesburg, South Africa between October 2007 and June 2008. The majority of participants reported engaging in sexual activity following diagnosis with AHI with a significant minority reporting unprotected sex during this time. Most participants perceived to have changed their behavior following diagnosis. However, participants reported barriers to condom use and abstinence, in particular, long term relationships and the need for disclosure of sero-status. Understanding of increased infectiousness during AHI was limited. Participants reported a desire for a behavioral intervention at the time of AHI diagnosis, however, there were differences by country in the types of interventions participants found acceptable. Studies are underway to determine the feasibility, acceptability and potential effectiveness of interventions designed for individuals with AHI. © Springer Science+Business Media, LLC 2010. Source
Tang W.,University of North Carolina at Chapel Hill |
Harmon P.,University of North Carolina at Chapel Hill |
Gulley M.L.,University of North Carolina at Chapel Hill |
Mwansambo C.,Kamuzu Central Hospital |
And 9 more authors.
Clinical Cancer Research | Year: 2010
Purpose: Some EBV-directed therapies are predicted to be effective only when lytic viral replication occurs. We studied whether cyclophosphamide chemotherapy induces EBV to switch from latent to lytic phases of infection in a series of EBV-associated Burkitt lymphomas. Experimental Design: Children with first presentation of an expanding, solid maxillary or mandibular mass consistent with Burkitt lymphoma underwent fine-needle aspiration just prior to the initiation of cyclophosphamide therapy and again 1 to 5 days later. Aspirated cells were examined for latent and lytic EBV infection using in situ hybridization to EBV-encoded RNA (EBER), immunohistochemical analysis of the lytic EBV proteins BZLF1 and BMRF1, reverse transcription PCR targeting BZLF1 transcripts, and EBV viral load measurement by quantitative PCR. Results: Among 21 lymphomas expressing EBER prior to chemotherapy, 9 of 10 still expressed EBER on day 1 after therapy whereas only 2 of 11 (18%) specimens still expressed EBER at days 3 to 5, implying that chemotherapy was fairly effective at eliminating latently infected cells. Neither of the lytic products, BZLF1 or BMRF1, were significantly upregulated at the posttherapy time points examined. However, EBV genomic copy number increased in 5 of 10 samples 1 day after treatment began, suggesting that viral replication occurs within the first 24 hours. Conclusion: Cyclophosphamide may induce the lytic phase of EBV infection and is fairly effective in diminishing EBER-expressing tumor cells within 5 days. These findings provide the rationale for a trial testing synergistic tumor cell killing using cyclophosphamide with a drug like ganciclovir targeting lytically infected cells. ©2010 AACR. Source
Powers K.A.,University of North Carolina at Chapel Hill |
Ghani A.C.,Imperial College London |
Miller W.C.,University of North Carolina at Chapel Hill |
Hoffman I.F.,University of North Carolina at Chapel Hill |
And 4 more authors.
The Lancet | Year: 2011
HIV transmission risk is higher during acute and early HIV infection than it is during chronic infection, but the contribution of early infection to the spread of HIV is controversial. We estimated the contribution of early infection to HIV incidence in Lilongwe, Malawi, and predict the future effect of hypothetical prevention interventions targeted at early infection only, chronic infection only, or both stages. We developed a deterministic mathematical model describing heterosexual HIV transmission, informed by detailed behavioural and viral-load data collected in Lilongwe. We included sexual contact within and outside of steady pairs and divided the infectious period into intervals to allow for changes in transmissibility by infection stage. We used a Bayesian melding approach to fit the model to HIV prevalence data collected between 1987 and 2005 at Lilongwe antenatal clinics. We assessed interventions that reduced the per-contact transmission probability to 0·00003 in people receiving them, and varied the proportion of individuals receiving the intervention in each stage. We estimated that 38·4 (95 credible interval 18·6-52·3) of HIV transmissions in Lilongwe are attributable to sexual contact with individuals with early infection. Interventions targeted at only early infection substantially reduced HIV prevalence, but did not lead to elimination, even with 100 coverage. Interventions targeted at only chronic infections also reduced HIV prevalence, but coverage levels of 95-99 were needed for the elimination of HIV. In scenarios with less than 95 coverage of interventions targeted at chronic infections, additional interventions reaching 25-75 of individuals with early infection reduced HIV prevalence substantially. Our results suggest that early infection plays an important part in HIV transmission in this sub-Saharan African setting. Without near-complete coverage, interventions during chronic infection will probably have incomplete effectiveness unless complemented by strategies targeting individuals with early HIV infection. National Institutes of Health, University of North Carolina Center for AIDS Research. © 2011 Elsevier Ltd. Source
Sanders E.J.,Kenya Medical Research Institute |
Sanders E.J.,University of Oxford |
Sanders E.J.,University of Amsterdam |
Wahome E.,Kenya Medical Research Institute |
And 11 more authors.
AIDS | Year: 2015
Background: Patients with acute HIV-1 infection (AHI) have elevated infectivity, but cannot be diagnosed using antibody-based testing. Approaches to screen patients for AHI are urgently needed to enable counselling and treatment to reduce onward transmission. Methods: We pooled data from four African studies of high-risk adults that evaluated symptoms and signs compatible with acute retroviral syndrome and tested for HIV-1 at each visit. AHI was defined as detectable plasma viral load or p24 antigen in an HIV-1-antibody-negative patient who subsequently seroconverted. Using generalized estimating equation, we identified symptoms, signs, and demographic factors predictive of AHI, adjusting for study site. We assigned a predictor score to each statistically significant predictor based on its beta coefficient, summing predictor scores to calculate a risk score for each participant. We evaluated the performance of this algorithm overall and at each site. Results: We compared 122 AHI visits with 45 961 visits by uninfected patients. Younger age (18-29 years), fever, fatigue, body pains, diarrhoea, sore throat, and genital ulcer disease were independent predictors of AHI. The overall area under the receiver operating characteristics curve (AUC) for the algorithm was 0.78, with sitespecific AUCs ranging from 0.61 to 0.89. A risk score of at least 2 would indicate AHI testing for 5-50% of participants, substantially decreasing the number needing testing. Conclusion: Our targeted risk score algorithm based on seven characteristics reduced the number of patients needing AHI testing and had good performance overall. We recommend this risk score algorithm for use by HIV programs in sub-Saharan Africa with capacity to test high-risk patients for AHI. © 2015 Wolters Kluwer Health, Inc. All rights reserved. Source