Publications by authors named "Lynn A Paxton"

Transmission of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), is ongoing in many communities throughout the United States. Although case-based and syndromic surveillance are critical for monitoring the pandemic, these systems rely on persons obtaining testing or reporting a COVID-19-like illness. Using serologic tests to detect the presence of SARS-CoV-2 antibodies is an adjunctive strategy that estimates the prevalence of past infection in a population.

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Background: Mass drug administration (MDA) appears to be effective in reducing the risk of malaria parasitaemia. This study reports on programmatic coverage and compliance of MDA using artemisinin-based combination therapy (ACT) in four shehias (smallest administration unit) that had been identified as hotspots through Zanzibar's malaria case notification surveillance system.

Methods: Mass drug administration was done in four shehias selected on the basis of: being an established malaria hot spot; having had mass screening and treatment (MSaT) 2-6 weeks previously; and exceeding the epidemic alert threshold of 5 cases within a week even after MSaT.

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Background: Malaria in pregnancy (MiP) remains a major public health challenge in areas of high malaria transmission. Intermittent preventive treatment in pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP) is recommended to prevent the adverse consequences of MiP. The effectiveness of SP for IPTp may be reduced in areas where the dhps581 mutation (a key marker of high level SP resistance) is found; this mutation was previously reported to be common in the Tanga Region of northern Tanzania, but there are limited data from other areas.

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Article Synopsis
  • - The Bangkok Tenofovir Study (BTS) found that daily tenofovir as pre-exposure prophylaxis (PrEP) can lower HIV infection risk by 49% in people who inject drugs, leading to an extension offering participants one year of open-label PrEP.
  • - The study included 1,315 eligible participants from the BTS, revealing that 61% chose to start PrEP, with 42% completing 12 months of follow-up and factors like age, heroin use, and prior imprisonment influencing adherence rates.
  • - Data was collected through self-interviews every three months, and findings suggest that older age and specific drug use habits correlated with better uptake and adherence to PrEP, promoting the importance of
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Background: Rapid easy-to-use HIV tests offer opportunities to increase HIV testing among populations at risk of infection. We used the OraQuick Rapid HIV-1/2 antibody test (OraQuick) in the Bangkok Tenofovir Study, an HIV pre-exposure prophylaxis trial among people who inject drugs.

Methods: The Bangkok Tenofovir Study was a randomized, double-blind, placebo-controlled trial.

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Objective: To describe participant adherence to daily oral tenofovir in an HIV preexposure prophylaxis (PrEP) trial, examine factors associated with adherence, and assess the impact of adherence on the risk of HIV infection.

Design: The Bangkok Tenofovir Study was a randomized, double-blind, placebo-controlled trial conducted among people who inject drugs, 2005-2012.

Methods: Participants chose daily visits or monthly visits.

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Objectives: We examined the causes of hospitalization and death of people who inject drugs participating in the Bangkok Tenofovir Study, an HIV preexposure prophylaxis trial.

Methods: The Bangkok Tenofovir Study was a randomized, double-blind, placebo-controlled trial conducted during 2005 to 2012 among 2413 people who inject drugs. We reviewed medical records to define the causes of hospitalization and death, examined participant characteristics and risk behaviors to determine predictors of death, and compared the participant mortality rate with the rate of the general population of Bangkok, Thailand.

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Article Synopsis
  • - The study on product adherence in Botswana's oral pre-exposure prophylaxis trial found that among 1,219 participants, the adherence rate was high at 94% based on both pill counts and self-reports.
  • - Key factors influencing adherence included adverse events like nausea and concerns about side effects, with self-reported adherence linked to having an HIV-positive partner and living in Francistown.
  • - Main barriers to adherence were refill delays and logistical issues, while the use of cellphone alarms was identified as an effective strategy to improve adherence.
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Background: Tenofovir disoproxil fumarate (tenofovir) has been associated with renal dysfunction in people infected with human immunodeficiency virus (HIV) receiving combination antiretroviral therapy. We reviewed data from an HIV preexposure prophylaxis trial to determine if tenofovir use was associated with changes in renal function in an HIV-uninfected population.

Methods: During the trial, 2413 HIV-uninfected people who inject drugs were randomized to receive tenofovir or placebo.

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Introduction: Accurate clinical laboratory reference values derived from a local or regional population base are required to correctly interpret laboratory results. In Botswana, most reference intervals used to date are not standardized across clinical laboratories and are based on values derived from populations in the United States or Western Europe.

Methods: We measured 14 hematologic and biochemical parameters of healthy young adults screened for participation in the Botswana HIV Pre-exposure Prophylaxis Study using tenofovir disoproxil fumarate and emtricitabine (TDF/FTC) (TDF2 Study).

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Introduction: HIV spread rapidly among people who inject drugs in Bangkok in the late 1980s. In recent years, changes in drug use and HIV-associated risk behaviors have been reported. We examined data from the Bangkok Tenofovir Study, an HIV pre-exposure prophylaxis trial conducted among people who inject drugs, to assess participant risk behavior and drug use, and to identify risk factors for HIV infection.

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Background: Tenofovir-emtricitabine (TDF-FTC) pre-exposure prophylaxis (PrEP) has been found to be effective for prevention of HIV infection in several clinical trials. Two studies of TDF PrEP among men who have sex with men showed slight bone mineral density (BMD) loss. We investigated the effect of TDF and the interaction of TDF and hormonal contraception on BMD among HIV-uninfected African men and women.

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We examined CD4 cell count and plasma viral load patterns among Botswana TDF/FTC Oral HIV Prophylaxis Trial (TDF2 study) participants who seroconverted, comparing participants assigned to receive tenofovir/emtricitabine with participants assigned to receive placebo. We also evaluated for antiretroviral drug resistance among the breakthrough HIV infections. Among nine seroconverters assigned to tenofovir/emtricitabine and 24 to placebo, there were no significant differences in their CD4 cell count or viral load profiles over time.

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Background: Antiretroviral pre-exposure prophylaxis reduces sexual transmission of HIV. We assessed whether daily oral use of tenofovir disoproxil fumarate (tenofovir), an antiretroviral, can reduce HIV transmission in injecting drug users.

Methods: In this randomised, double-blind, placebo-controlled trial, we enrolled volunteers from 17 drug-treatment clinics in Bangkok, Thailand.

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Objectives: To evaluate the clinical safety of daily tenofovir disoproxil fumarate (TDF) among HIV-negative men who have sex with men.

Design: Randomized, double-blind, placebo-controlled trial. Participants were randomized 1:1:1:1 to immediate or delayed study drug (TDF, 300 mg orally per day, or placebo).

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Purpose Of Review: To discuss the factors pertinent to the use of pre-exposure prophylaxis (PrEP) by at-risk heterosexuals in countries with generalized HIV epidemics.

Recent Findings: PrEP will have the greatest prevention effect if targeted to those at highest risk, but identifying and engaging such persons is challenging. Serodiscordant couples account for a high proportion of new infections and are an appropriate target for PrEP, but the proportion of people in such relationships is small and outside partnerships are common.

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Background: Preexposure prophylaxis with antiretroviral agents has been shown to reduce the transmission of human immunodeficiency virus (HIV) among men who have sex with men; however, the efficacy among heterosexuals is uncertain.

Methods: We randomly assigned HIV-seronegative men and women to receive either tenofovir disoproxil fumarate and emtricitabine (TDF-FTC) or matching placebo once daily. Monthly study visits were scheduled, and participants received a comprehensive package of prevention services, including HIV testing, counseling on adherence to medication, management of sexually transmitted infections, monitoring for adverse events, and individualized counseling on risk reduction; bone mineral density testing was performed semiannually in a subgroup of participants.

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In a changing public health landscape in which local, state, and federal agencies must confront threats of bioterrorism, emerging infections, and numerous chronic diseases, transmission of HIV among injection drug users (IDUs) continues to be an important public health issue and one of the driving forces behind the HIV epidemic. Using a computerized MEDLINE search of published articles from January 1981 through October 2005, we conducted a literature review of practical epidemiologic aspects of HIV/AIDS among IDUs in the United States. Although recent trends indicate a decline in the proportion of newly diagnosed HIV infections associated with injection drug use, drug-use behaviors overall still account for 32% of new HIV diagnoses.

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The most effective means of preventing human immunodeficiency virus (HIV) infection is preventing exposure. The provision of antiretroviral drugs to prevent HIV infection after unanticipated sexual or injection-drug--use exposure might be beneficial. The U.

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