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Dive into the research topics where David Chilongozi is active.

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Featured researches published by David Chilongozi.


AIDS | 2007

Amplified transmission of HIV-1: comparison of HIV-1 concentrations in semen and blood during acute and chronic infection

Christopher D. Pilcher; George Joaki; Irving Hoffman; Francis Martinson; Clement Mapanje; Paul W. Stewart; Kimberly A. Powers; Shannon Galvin; David Chilongozi; Syze Gama; Matthew Price; Susan A. Fiscus; Myron S. Cohen

Objectives:This study was conducted to compare viral dynamics in blood and semen between subjects with antibody negative, acute HIV-1 infection and other subjects with later stages of infection. Design:A prospective cohort study was embedded within a cross-sectional study of HIV screening in a Lilongwe, Malawi STD clinic. Methods:Blood samples from HIV antibody negative or indeterminate volunteers were used to detect HIV RNA in plasma using a pooling strategy. Blood and seminal plasma HIV-1 RNA concentrations were measured over 16 weeks. Results:Sixteen men with acute HIV infection and 25 men with chronic HIV infection were studied. Blood viral load in subjects with acute HIV infection was highest about 17 days after infection (mean ± SE, 6.9 ± 0.5 log10 copies/ml), while semen viral load peaked about 30 days after infection (4.5 ± 0.4 log10 copies/ml). Semen viral load declined by 1.7 log10 to a nadir by week 10 of HIV infection. Semen and blood viral loads were more stable in chronically infected subjects over 16 weeks. Higher semen levels of HIV RNA were noted in subjects with low CD4 cell counts. Conclusions:These results provide a biological explanation for reported increases in HIV transmission during the very early (acute) and late stages of infection. Recognizing temporal differences in HIV shedding in the genital tract is important in the development of effective HIV prevention strategies.


Journal of Acquired Immune Deficiency Syndromes | 2008

The year-long effect of HIV-positive test results on pregnancy intentions, contraceptive use, and pregnancy incidence among Malawian women.

Irving Hoffman; Francis Martinson; Kimberly A. Powers; David Chilongozi; Emmie D Msiska; Emma I Kachipapa; Chimwemwe D Mphande; Mina C. Hosseinipour; Harriet C Chanza; Rob Stephenson; Amy O. Tsui

Objectives:To estimate the effect of receiving HIV-positive test results on intentions to have future children and on contraceptive use and to assess the association between pregnancy intentions and pregnancy incidence among HIV-positive women in Malawi. Methods:Women of unknown HIV status completed a questionnaire about pregnancy intentions and contraceptive use and then received HIV voluntary counseling and testing (VCT). Women who were HIV-positive and not pregnant were enrolled and followed for 1 year while receiving HIV care and access to family planning (FP) services. Results:Before receiving their HIV test results, 33% of women reported a desire to have future children; this declined to 15% 1 week later (P < 0.0001) and remained constant throughout follow-up. Contraceptive use increased from 38% before HIV testing to 52% 1 week later (P < 0.0001) and then decreased to 46% by 12 months. The pregnancy incidence among women not reporting a desire to have future children after VCT was less than half of the incidence among women reporting this desire. Conclusions:With knowledge of their HIV-positive status, women were less likely to desire future pregnancies. Pregnancy incidence was lower among women not desiring future children. Integration of VCT, FP, and HIV care could prevent mother-to-child HIV transmission.


The Journal of Infectious Diseases | 2007

Rapid real-time detection of acute HIV infection in patients in Africa.

Susan A. Fiscus; Christopher D. Pilcher; William C. Miller; Kimberly A. Powers; Irving Hoffman; Matthew Price; David Chilongozi; Clement Mapanje; Robert Krysiak; Syze Gama; Francis Martinson; Myron S. Cohen

BACKGROUND We conducted a prospective study to evaluate methods of detecting clients with sexually transmitted diseases (STDs) who were acutely coinfected with human immunodeficiency virus (HIV) in Lilongwe, Malawi. METHODS After informed consent was obtained, all clients with acute STDs were offered voluntary HIV counseling and testing by 2 rapid antibody tests. Samples from rapid test-negative or -discordant subjects were pooled (50 : 5 : 1) and tested for HIV RNA. Western blots were performed on all rapid test-discordant specimens with detectable HIV RNA. A subset of specimens received p24 antigen testing with standard and/or ultrasensitive methods. Patients with possible acute HIV infection were followed to confirm seroconversion. RESULTS A total of 1450 clients (34% female and 66% male) agreed to testing, of whom 588 (40.55%) had established HIV infection and 21 (1.45%) had acute infection. Discordant rapid antibody tests identified 7 of 21 (33.3% sensitivity), standard p24 antigen identified 12 of 16 (75% sensitivity), and ultrasensitive p24 antigen identified 15 of 17 (88% sensitivity) acute cases. By definition, the sensitivity of the RNA assay was 100%. CONCLUSIONS Real-time pooled RNA testing for the detection of acute HIV infection is feasible in resource-limited settings. However, parallel rapid testing and p24 antigen testing are technologically simpler and together may detect approximately 90% of acute cases.


Sexually Transmitted Diseases | 2003

Addition of treatment for trichomoniasis to syndromic management of urethritis in Malawi: a randomized clinical trial.

Matthew Price; Dickman Zimba; Irving Hoffman; S. Cornelia Kaydos-Daniels; William C. Miller; Francis Martinson; David Chilongozi; Ester Kip; Esnath Msowoya; Marcia M. Hobbs; Peter N. Kazembe; Myron S. Cohen

Background Male urethritis is generally treated syndromically, but failure of empirical treatment is common. Goal The study goal was to evaluate the addition of metronidazole to the syndromic management of urethritis in Malawi in a randomized clinical trial. Study Design Men with urethritis were randomized to receive either 2 g of metronidazole by mouth or placebo, in addition to standard care for urethritis (i.e., a single intramuscular dose of 240 mg gentamicin and 100 mg doxycycline twice daily for 7 days). The primary endpoints of the study included measurement of the effects of treatment on Trichomonas vaginalis, signs and symptoms of urethritis, and the concentration of HIV RNA in semen in dually infected subjects. Results The overall prevalence of T vaginalis was 17.3% (71/411), and treatment with metronidazole cleared 95% of culture-positive infections, compared with 54% clearance among men receiving placebo (P = 0.006). Prevalence of persistent urethritis was observed in approximately 16% of both groups at the end of 1 week (29/179 of those receiving metronidazole versus 29/187 in the placebo group;P = 0.86). For a subset of HIV-infected men with trichomoniasis, the seminal plasma HIV RNA concentration was lower than in a group of HIV-positive control subjects (P = 0.052). Conclusion In areas with a high prevalence of trichomoniasis, the addition of metronidazole to the syndromic management of male urethritis can eliminate infection with T vaginalis and may help to reduce the transmission of HIV. Such treatment should be strongly considered as part of empirical therapy for urethritis in men in Malawi and places where T vaginalis infection in men is common.


Pediatric Infectious Disease Journal | 2008

Morbidity and mortality among a cohort of human immunodeficiency virus type 1-infected and uninfected pregnant women and their infants from Malawi, Zambia, and Tanzania

David Chilongozi; Lei Wang; Lillian B. Brown; Taha E. Taha; Megan Valentine; Lynda Emel; George Kafulafula; Ramadhani A. Noor; Jennifer S. Read; Elizabeth R. Brown; Robert L. Goldenberg; Irving Hoffman

Background: Morbidity and mortality patterns among pregnant women and their infants (before antiretroviral therapy was widely available) determines HIV-1 diagnostic, monitoring, and care interventions. Methods: Data from mothers and their infants enrolled in a trial of antibiotics to reduce mother-to-child-transmission of HIV-1 at 4 sub-Saharan African sites were analyzed. Women were enrolled during pregnancy and follow-up continued until the infants reached 12 months of age. We describe maternal and infant morbidity and mortality in a cohort of HIV-1-infected and HIV-1-uninfected mothers. Maternal and infant factors associated with mortality risk in the infants were assessed using Cox proportional hazard modeling. Results: Among 2292 HIV-1-infected mothers, 166 (7.2%) had a serious adverse event (SAE) and 42 (1.8%) died, whereas no deaths occurred among the 331 HIV-1 uninfected mothers. Four hundred twenty-four (17.8%) of 2383 infants had an SAE and 349 (16.4%) died before the end of follow-up. Infants with early HIV-1 infection (birth to 4–6 weeks) had the highest mortality. Among infants born to HIV-1-infected women, maternal morbidity and mortality (P = 0.0001), baseline CD4 count (P = 0.0002), and baseline plasma HIV-1 RNA concentration (P < 0.0001) were significant predictors of infant mortality in multivariate analyses. Conclusions: The high mortality among infants with early HIV-1 infection supports access to HIV-1 diagnostics and appropriate early treatment for all infants of HIV-1-infected mothers. The significant association between stage of maternal HIV-1 infection and infant mortality supports routine CD4 counts at the time of prenatal HIV-1 testing.


AIDS | 2007

Improved detection of acute HIV-1 infection in sub-Saharan Africa: development of a risk score algorithm.

Kimberly A. Powers; William C. Miller; Christopher D. Pilcher; Clement Mapanje; Francis Martinson; Susan A. Fiscus; David Chilongozi; David Namakhwa; Matthew Price; Shannon Galvin; Irving Hoffman; Myron S. Cohen

Objective:Individuals with acute (preseroconversion) HIV infection (AHI) are important in the spread of HIV. The identification of AHI requires the detection of viral proteins or nucleic acids with techniques that are often unaffordable for routine use. To facilitate the efficient use of these tests, we sought to develop a risk score algorithm for identifying likely AHI cases and targeting the tests towards those individuals. Design:A cross-sectional study of 1448 adults attending a sexually transmitted infections (STI) clinic in Malawi. Methods:Using logistic regression, we identified risk behaviors, symptoms, HIV rapid test results, and STI syndromes that were predictive of AHI. We assigned a model-based score to each predictor and calculated a risk score for each participant. Results:Twenty-one participants (1.45%) had AHI, 588 had established HIV infection, and 839 were HIV-negative. AHI was strongly associated with discordant rapid HIV tests and genital ulcer disease (GUD). The algorithm also included diarrhea, more than one sexual partner in 2 months, body ache, and fever. Corresponding predictor scores were 1 for fever, body ache, and more than one partner; 2 for diarrhea and GUD; and 4 for discordant rapid tests. A risk score of 2 or greater was 95.2% sensitive and 60.5% specific in detecting AHI. Conclusion:Using this algorithm, we could identify 95% of AHI cases by performing nucleic acid or protein tests in only 40% of patients. Risk score algorithms could enable rapid, reliable AHI detection in resource-limited settings.


Sexually Transmitted Diseases | 2006

HIV Incidence Among Women of Reproductive Age in Malawi and Zimbabwe

Newton Kumwenda; Irving Hoffman; Mike Chirenje; Clifton W. Kelly; Anne Coletti; Aleen Ristow; Francis Martinson; Joelle Brown; David Chilongozi; Barbra A. Richardson; Zeda Rosenberg; Nancy S. Padian; Taha E. Taha

Objective: The objective of this study was to determine the incidence of HIV-1. Goal: The goal of this study was to inform HIV prevention and vaccine trials by conducting a multisite study in Malawi and Zimbabwe. Study Design: Women of reproductive age were enrolled in a prospective study. They received 5 intensive HIV counseling and condom promotion sessions over 2 months. Subsequently, HIV-negative women completed quarterly follow-up visits. HIV incidence rates and predictors of HIV acquisition were assessed. Results: A total of 2016 HIV-negative women were enrolled in the condom promotion and counseling phase of the study. Of these, 1679 were tested for HIV during follow up and 113 women seroconverted, resulting in an overall HIV incidence rate of 4.7 per 100 women-years (95% confidence interval = 3.8–5.6). Incidence rates were similar across sites. The major predictors of HIV acquisition were young age, presence of sexually transmitted infections, being unmarried, and higher educational level. Conclusion: The incidence of HIV continues to be high among women in both Malawi and Zimbabwe despite counseling and condom promotion.


The Journal of Infectious Diseases | 2003

Human Immunodeficiency Virus Type 1 RNA in Breast-Milk Components

Irving Hoffman; Francis Martinson; Paul W. Stewart; David Chilongozi; Szu Yun Leu; Peter N. Kazembe; Topia Banda; Willard Dzinyemba; Priya Joshi; Myron S. Cohen; Susan A. Fiscus

We conducted the present study to determine which of the 4 components of breast milk (whole milk, skim milk, lipid layer, and breast-milk cells) had the highest sensitivity and concentration of human immunodeficiency virus (HIV) type 1 RNA burden and to determine biological correlates to these factors. The probability of detection of HIV (sensitivity) and the concentration of HIV-1 RNA were both associated with the choice of milk component, CD4(+) cell count, concentration of blood serum HIV-1 RNA, and the presence of breast inflammation. Whole milk demonstrated higher sensitivity and mean concentration than any other single component. Sensitivity was enhanced by analyzing all 4 components of breast milk.


AIDS | 2004

Nonoxynol-9 100 mg gel: multi-site safety study from sub-Saharan Africa.

Irving Hoffman; Taha E. Taha; Nancy S. Padian; Clifton W. Kelly; Julia D. Welch; Francis Martinson; Newton Kumwenda; Zeda Rosenberg; David Chilongozi; Joelle Brown; Michael Chirenje; Barbra A. Richardson

Objectives: To evaluate the safety of 100 mg nonoxynol-9 (N-9) gel, a vaginal microbicide, on the genital mucosa of women from Malawi and Zimbabwe in preparation for a phase III efficacy study. Methods: HIV-uninfected women (180) were enrolled and randomized to either N-9 or placebo gel and instructed to insert gel into the vagina twice daily for 14 days. Follow up examinations were conducted at 7 and 14 days. Results: The number of adverse events in the N-9 gel group was higher than in the placebo group (40% versus 13%; P < 0.01). Reported number of any genital symptoms was significantly higher in the N-9 group (38% N-9, 13% placebo; P = 0.01). The number of total epithelial disruptions was higher in the N-9 group (20% versus 3%; P < 0.01); however, the number of genital ulcers and abrasions in the N-9 group was low (2% and 3%, respectively) and not different from that in the placebo group (1% and 2%, respectively). Conclusions: N-9 gel 100 mg caused a significant increase in the rate of genital symptoms and epithelial disruptions compared with placebo. The clinical significance of these epithelial disruptions is unknown. Although these findings alone were not sufficient to cancel the planned phase III study, when considered together with the negative results from the COL-1492 effectiveness trial of 52.5 mg N-9 gel, the decision was made to cancel the planned phase III trial of 100 mg N-9 gel.


The Journal of Infectious Diseases | 2004

The use of specimens from various genitourinary sites in men, to detect Trichomonas vaginalis infection

S. Cornelia Kaydos-Daniels; William C. Miller; Irving Hoffman; Matthew Price; Francis Martinson; David Chilongozi; David Namakwha; Syze Gama; Seveliano Phakati; Myron S. Cohen; Marcia M. Hobbs

Variations in estimates of prevalence of trichomoniasis in men may reflect true differences in the burden of disease but are also affected by the performance of diagnostic methods and the type of specimen tested. In this study, men were evaluated at baseline and at follow-up, to evaluate syndromic management of urethritis and the effects of human immunodeficiency virus and trichomoniasis, in Lilongwe, Malawi. First-void urine specimens and urethral swabs were obtained at enrollment, for Trichomonas vaginalis culture; semen specimens were also obtained at follow-up. The sensitivities of testing methods using urine specimens and urethral swabs were equal; 67% of cases were identified by use of either specimen, and, in 47% of cases, both specimens tested positive. When semen specimens were included, all 3 specimens tested positive in only 19% of cases. Semen was the most sensitive single specimen, and, in 25.6% of cases, only semen specimens tested positive. Thus, prevalence of T. vaginalis infection in men is underestimated if only 1 specimen is tested.

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Francis Martinson

University of North Carolina at Chapel Hill

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Irving Hoffman

University of North Carolina at Chapel Hill

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Myron S. Cohen

University of North Carolina at Chapel Hill

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Susan A. Fiscus

University of North Carolina at Chapel Hill

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Kimberly A. Powers

University of North Carolina at Chapel Hill

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Cheng Yen Chen

Centers for Disease Control and Prevention

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