Publications by authors named "Tyson Volkmann"

Many SARS-CoV-2 infections are asymptomatic, thus reported cases underestimate actual cases. To improve estimates, we conducted surveillance for SARS-CoV-2 seroprevalence among pregnant women attending their first antenatal care visit (ANC1) from June 2021 through May 2022. We administered a questionnaire to collect demographic, risk factors, and COVID-19 vaccine status information and tested dried blood spots for SARS-CoV-2 antibodies.

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In the Caribbean region, HIV prevalence is high among key population (KP) groups, such as sex workers and men who have sex with men. However, there is a lack of high-quality, population-level data estimating HIV prevalence and population sizes of KPs. The President's Emergency Plan for AIDS Relief has funded and completed five bio-behavioral surveillance (BBS) surveys using respondent-driven sampling methodology to target KP in the English-speaking Caribbean region.

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Background: The Global Fund encourages operational research (OR) in all its grants; however very few reports describe this aspect. In India, Project Axshya was supported by a Global Fund grant to improve the reach and visibility of the government Tuberculosis (TB) services among marginalised and vulnerable communities. OR was incorporated to build research capacity of professionals working with the national TB programme and to generate evidence to inform policies and practices.

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HIV testing among persons with tuberculosis (TB) results in high-yield identification of persons infected with HIV. To evaluate differences in HIV testing among children versus adults with TB in Vietnam, we collected and analyzed age-disaggregated facility and aggregated provincial data from the National Tuberculosis Program. HIV testing was incompletely documented for >70% of children, whereas adult testing data were >90% complete.

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Introduction: Poverty and poor nutrition are associated with the risk of developing tuberculosis (TB). Socioeconomic factors may interfere with anti-tuberculosis treatment compliance and its outcome. We examined whether providing nutritional support (monthly supply of rice and lentil beans) to TB patients who live below the poverty line was associated with TB treatment outcome.

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Introduction: Treatment completion is the cornerstone of tuberculosis (TB) control strategy globally. Although the majority of reported TB cases in the U.S.

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We followed 188 euthyroidic persons undergoing treatment for multidrug resistant tuberculosis (MDR-TB) in the state of Karnataka, India to determine the incidence of hypothyroidism during anti-tuberculosis treatment. Overall, among MDR-TB patients with valid thyroid stimulating hormone (TSH) values, about 23% developed hypothyroidism (TSH value ≥10 mIU/ml) during anti-tuberculosis treatment; the majority (74%) occurring after 3 months of treatment. Among 133 patients who received a regimen that contained ethionamide, 42 (32%) developed hypothyroidism.

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Rationale: Excess alcohol use (EAU) is associated with adverse TB treatment outcomes.

Objective: We investigated the relationship between EAU and death among TB patients 15 years and older prescribed anti-TB treatment in the United States.

Design: Using data reported to the National Tuberculosis Surveillance System for 1997-2012, we calculated adjusted odds ratios and excess attributable risk percent for death among TB patients with reported EAU.

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Male clients of female sex workers (FSWs) in Tijuana, Mexico engage in high levels of unprotected sex. While behavioral change theories posit that self-efficacy predicts condom use, correlates of self-efficacy for condom use remain largely unstudied. We examined these correlates among male clients of FSWs in Tijuana.

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The authors report the results of qualitative (n = 19) and quantitative (n = 545) interviews with young injection drug users (IDUs) in San Diego, California about their experiences using drugs in Tijuana, Mexico, and associated risks for HIV infection. Young IDUs who have ever traveled to Mexico (n = 365) used a variety of injection (54%) and noninjection (30%) drugs there and appear to be heavier users than those who have never traveled to Mexico. Sociocultural themes influencing drug use in Mexico included interactions among the purpose of travel, drug preference, and route of administration; familiarity with the border region; evolving relationships with the United States and Mexican drug markets; and the experience of crossing the U.

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We examined drug-scene familiarity and exposure to gang violence among residents of a migrant farming community in rural Baja California, Mexico. In October 2010, 164 members of a single colonia (community) underwent an interviewer-administered survey to assess 'exposure to gang violence' and 'drug-scene familiarity', as well as other health indicators. Logistic regression was used to identify correlates of exposure to gang violence.

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Objective: To gain insights into bridging behaviors and their correlates among male clients of female sex workers (FSWs).

Methods: Men aged ≥18 years who recently paid or traded for sex with FSWs were recruited in Tijuana in 2008-2009. Participants underwent interviews and testing for HIV, chlamydia, syphilis, and gonorrhea.

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Although rates of methamphetamine use continue to increase throughout the United States, little is known about the individuals who sell methamphetamine at the street level. This exploratory study examined the prevalence and correlates of drug-dealing behavior in a sample of 404 heterosexually identified methamphetamine users who were participants in a sexual risk reduction intervention in San Diego, California. Twenty-nine percent of participants (N = 116) reported "dealing" methamphetamine in the past 2 months.

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Objective: To assess factors associated with drug-related harms related to policing among injection drug users (IDUs) in Tijuana, Mexico.

Methods: IDUs who were over 18 years old and had injected drugs within the last six months were recruited via respondent-driven sampling and underwent questionnaires and testing for HIV (human immunodeficiency virus), syphilis and TB (tuberculosis). Random effects logistic regression was used to simultaneously model factors associated with five drug-related harms related to policing practices in the prior six months (i.

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We examined correlates of ever injecting drugs in Mexico among residents of San Diego, California. From 2007 to 2010, injecting drug users (IDUs) in San Diego underwent an interviewer-administered survey. Logistic regression identified correlates of injection drug use in Mexico.

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Background: International borders are unique social and environmental contexts characterized by high levels of mobility. Among drug users, mobility increases risk for human immunodeficiency virus (HIV) in part through its effects on the social environment. However, the social dynamics of drug users living in border regions are understudied.

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