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Dive into the research topics where Pollyanna Chavez is active.

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Featured researches published by Pollyanna Chavez.


Journal of Clinical Virology | 2011

Evaluation of the performance of the Abbott ARCHITECT HIV Ag/Ab Combo Assay.

Pollyanna Chavez; Laura G. Wesolowski; Pragna Patel; Kevin P. Delaney; S. Michele Owen

BACKGROUND Worldwide, many countries test for HIV infection using combination assays that simultaneously detect p24 antigen and HIV antibodies. One such assay, the ARCHITECT(®) HIV Ag/Ab Combo Assay (ARCHITECT), has recently been approved by the Food and Drug Administration (FDA) for use in the United States. OBJECTIVE To evaluate the performance of ARCHITECT on well-characterized specimens from four CDC-funded studies. STUDY DESIGN We evaluated 3386 HIV-infected, 7551 HIV-uninfected, and 58 acute HIV infection (AHI) specimens. HIV-infected specimens were repeatedly reactive by enzyme immunoassay (EIA) and Western blot (WB) or positive by nucleic acid amplification testing (NAAT). HIV-uninfected specimens were EIA- and NAAT-negative. AHI specimens were seronegative or indeterminate (using antibody-based EIAs, rapid tests or WB) and NAAT-positive. All specimens were de-identified and sent to Abbott Diagnostics for testing with ARCHITECT. ARCHITECT test results were compared to original study characterizations and were used to assess overall sensitivity and specificity and also sensitivity for AHI. ARCHITECT false-positive specimens with sufficient quantity were retested. RESULTS Based on results from the initial ARCHITECT test, sensitivity was 99.94% (95% confidence interval [CI]: 99.79, 99.99) and specificity was 98.78% (95% CI: 98.51-99.01). Repeat testing resulted in corrected specificity of 99.50% (95% CI: 99.31, 99.64). Also, 48 AHI specimens (83%) were detected by this screening assay. CONCLUSION The sensitivity and specificity of the ARCHITECT combination assay are very high and most AHIs were detected by the assay. Use of Ag/Ab combination assays may improve the number of AHIs identified relative to existing FDA-approved HIV-antibody only based serologic assays, particularly in high incidence populations.


Drug and Alcohol Dependence | 2015

Binge drinking and risky sexual behavior among HIV-negative and unknown HIV status men who have sex with men, 20 US cities

Kristen L. Hess; Pollyanna Chavez; Dafna Kanny; Elizabeth DiNenno; Amy Lansky; Gabriela Paz-Bailey

BACKGROUND Men who have sex with men (MSM) represent over half of new HIV infections in the United States. It is important to understand the factors associated with engaging in risky sexual behavior to develop effective prevention interventions. Binge drinking (≥5 drinks on ≥1 occasion) is the most common form of excessive alcohol consumption. This study examines the relationship between binge drinking and sexual risk behaviors among MSM who are current drinkers and who were either HIV-negative or unaware of their HIV status. METHODS Using the 2011 National HIV Behavioral Surveillance system and multivariable Poisson models with robust error estimates, we assessed the association between binge drinking and sexual risk behaviors among current drinkers. Prevalence ratios (PR) and 95% confidence intervals (CI) are presented. RESULTS Overall, 85% of MSM were current drinkers, and 59% of MSM who drank reported ≥1 episode of binge drinking in the preceding 30 days. In multivariable models, binge drinking was associated with condomless anal intercourse (CAI) at last sex with an HIV-positive or unknown status partner (receptive: PR 1.3, 95% CI 1.1-1.6; insertive: PR 1.2, 95% CI 1.0-1.4), having exchanged sex for money or drugs at last sex (PR: 1.4, 95% CI 1.1-1.7), having concurrent partners in the past year (PR: 1.1, 95% CI 1.1-1.2), and having more CAI partners in the past year (PR: 1.2, 95% CI 1.0-1.4) compared to non-binge drinkers. CONCLUSIONS Evidence-based strategies for reducing binge drinking could help reduce risky sexual behavior among MSM.


PLOS ONE | 2012

Mortality, severe acute respiratory infection, and influenza-like illness associated with influenza A(H1N1)pdm09 in Argentina, 2009.

Eduardo Azziz-Baumgartner; Ana Cabrera; Loretta S. Chang; Rogelio Calli; Gabriela Kusznierz; Clarisa Baez; Pablo Yedlin; Ana María Zamora; Romina Cuezzo; Elena B Sarrouf; Andrea Uboldi; Juan Herrmann; Elsa Zerbini; Osvaldo Uez; Pedro Osvaldo Rico Cordeiro; Pollyanna Chavez; George Han; Julián Antman; Fátima Coronado; Joseph S. Bresee; Marina Kosacoff; Marc-Alain Widdowson; Horacio Echenique

Introduction While there is much information about the burden of influenza A(H1N1)pdm09 in North America, little data exist on its burden in South America. Methods During April to December 2009, we actively searched for persons with severe acute respiratory infection and influenza-like illness (ILI) in three sentinel cities. A proportion of case-patients provided swabs for influenza testing. We estimated the number of case-patients that would have tested positive for influenza by multiplying the number of untested case-patients by the proportion who tested positive. We estimated rates by dividing the estimated number of case-patients by the census population after adjusting for the proportion of case-patients with missing illness onset information and ILI case-patients who visited physicians multiple times for one illness event. Results We estimated that the influenza A(H1N1)pdm09 mortality rate per 100,000 person-years (py) ranged from 1.5 among persons aged 5–44 years to 5.6 among persons aged ≥65 years. A(H1N1)pdm09 hospitalization rates per 100,000 py ranged between 26.9 among children aged <5 years to 41.8 among persons aged ≥65 years. Influenza A(H1N1)pdm09 ILI rates per 100 py ranged between 1.6 among children aged <5 to 17.1 among persons aged 45–64 years. While 9 (53%) of 17 influenza A(H1N1)pdm09 decedents with available data had obesity and 7 (17%) of 40 had diabetes, less than 4% of surviving influenza A(H1N1)pdm09 case-patients had these pre-existing conditions (p≤0.001). Conclusion Influenza A(H1N1)pdm09 caused a similar burden of disease in Argentina as in other countries. Such disease burden suggests the potential value of timely influenza vaccinations.


PLOS ONE | 2012

An Analysis of 332 Fatalities Infected with Pandemic 2009 Influenza A (H1N1) in Argentina

Ana M. Balanzat; Christian Hertlein; Carlos Apezteguia; Pablo Bonvehi; Luis Cámera; Angela Gentile; Oscar Rizzo; Manuel Gómez-Carrillo; Fátima Coronado; Eduardo Azziz-Baumgartner; Pollyanna Chavez; Marc-Alain Widdowson

Background The apparent high number of deaths in Argentina during the 2009 pandemic led to concern that the influenza A H1N1pdm disease was different there. We report the characteristics and risk factors for influenza A H1N1pdm fatalities. Methods We identified laboratory-confirmed influenza A H1N1pdm fatalities occurring during June-July 2009. Physicians abstracted data on age, sex, time of onset of illness, medical history, clinical presentation at admission, laboratory, treatment, and outcomes using standardize questionnaires. We explored the characteristics of fatalities according to their age and risk group. Results Of 332 influenza A H1N1pdm fatalities, 226 (68%) were among persons aged <50 years. Acute respiratory failure was the leading cause of death. Of all cases, 249 (75%) had at least one comorbidity as defined by Advisory Committee on Immunization Practices. Obesity was reported in 32% with data and chronic pulmonary disease in 28%. Among the 40 deaths in children aged <5 years, chronic pulmonary disease (42%) and neonatal pathologies (35%) were the most common co-morbidities. Twenty (6%) fatalities were among pregnant or postpartum women of which only 47% had diagnosed co-morbidities. Only 13% of patients received antiviral treatment within 48 hours of symptom onset. None of children aged <5 years or the pregnant women received antivirals within 48 h of symptom onset. As the pandemic progressed, the time from symptom-onset to medical care and to antiviral treatment decreased significantly among case-patients who subsequently died (p<0.001). Conclusion Persons with co-morbidities, pregnant and who received antivirals late were over-represented among influenza A H1N1pdm deaths in Argentina, though timeliness of antiviral treatment improved during the pandemic.


Journal of Clinical Virology | 2013

Use of rapid HIV assays as supplemental tests in specimens with repeatedly reactive screening immunoassay results not confirmed by HIV-1 Western blot

Laura G. Wesolowski; Kevin P. Delaney; William A. Meyer; Amy J. Blatt; Berry Bennett; Pollyanna Chavez; Timothy C. Granade; Michele Owen

BACKGROUND An alternate HIV testing algorithm has been proposed which includes a fourth-generation immunoassay followed by an HIV-1/HIV-2 antibody differentiation supplemental test for reactive specimens and a nucleic acid test (NAT) for specimens with discordant results. OBJECTIVE To evaluate the performance of five rapid tests (Alere Clearview, Bio-Rad Multispot, OraSure OraQuick, MedMira Reveal, and Trinity Biotech Unigold) as the supplemental antibody assay in the algorithm. STUDY DESIGN A total of 3273 serum and plasma specimens that were third-generation immunoassay repeatedly reactive and Western blot (WB) negative or indeterminate were tested with rapid tests and NAT. Specimens were classified by NAT: (1) HIV-1 infected (NAT-reactive; n=184, 5.6%), (2) HIV-status unknown (NAT nonreactive; n=3078, 94.2%) or by Multispot, (3) HIV-2 positive (n=5), and (4) HIV-1 and HIV-2 positive (n=6). Excluding HIV-2 positive specimens, we calculated the proportion of reactive rapid tests among specimens with reactive and nonreactive NAT. RESULTS The proportion of infected specimens with reactive rapid test results and negative or indeterminate WB ranged from 30.4% (56) to 47.8% (88) depending on the rapid test. From 1% to 2% of NAT-negative specimens had reactive rapid test results. CONCLUSIONS In these diagnostically challenging specimens, all rapid tests identified infections that were missed by the Western blot, but only Multispot could differentiate HIV-1 from HIV-2. Regardless of which rapid test is used as a supplemental test in the alternative algorithm, false-positive algorithm results (i.e., reactive screening and rapid test in uninfected person) may occur, which will need to be resolved during the baseline medical evaluation.


Public Health Reports | 2014

Rapid HIV Testing at Gay Pride Events to Reach Previously Untested MSM: U.S., 2009-2010

Rennatus Mdodo; Peter E. Thomas; Anissa Walker; Pollyanna Chavez; Steven F. Ethridge; Emeka Oraka; Madeline Y. Sutton

We offered rapid HIV testing at social events frequented by young men who have sex with men (MSM), a group disproportionately affected by the HIV epidemic. We tested 1,312 MSM; of those MSM, 1,072 (81.7%) reported HIV testing history. Of those reporting HIV testing history, 550 (51.3%) were non-Hispanic black and 404 (37.7%) were aged <25 years. One hundred twenty-eight (11.9%) had never tested for HIV; 77 (7.2%) were preliminarily positive, with 15 (19.5%) being first-time testers. Factors associated with no previous HIV test included young age (13–24 years) (adjusted odds ratio [AOR] = 3.5, 95% confidence interval [CI] 1.9, 6.5) and non-Hispanic black (AOR=3.2, 95% CI 1.6, 6.4) or Hispanic (AOR=2.8, 95% CI 1.2, 6.3) race/ethnicity. HIV testing at Gay Pride events reaches young, previously untested MSM. This venue-based HIV testing approach at nonclinical sociocultural events is an additional strategy for HIV prevention goals to increase the number of people aware of their HIV infection with subsequent linkage to HIV care.


AIDS | 2015

Nonvolitional sex and HIV-related sexual risk behaviours among MSM in the United States.

Muazzam Nasrullah; Emeka Oraka; Pollyanna Chavez; Eduardo E. Valverde; Elizabeth DiNenno

Objective:We estimated the prevalence of lifetime nonvolitional sex (NVS) among MSM by demographic characteristics, and characterized its association with HIV-related sexual risk behaviours among MSM in the United States. Design:The National Survey of Family Growth (NSFG) is a nationally representative cross-sectional survey of the United States. Methods:NSFG data from recent cycles 2002, and 2006–2010 were weighted and analysed for men aged 18–44 years who reported ever having anal or oral intercourse with another male. Associations of lifetime NVS (forced sex by men or women) and age of first NVS experience (<18 vs. ≥18 years), with HIV-related sexual risk behaviour outcomes in the past 12 months (i.e. sex with two or more male sex partners; exchanged sex for money or drugs; sex with IDU; sex with HIV-positive person; sex with two or more female sex partners) were assessed using adjusted prevalence ratios (aPR). Results:An estimated 3 226 872 or 5.8% of men aged 18–44 years were identified as MSM with 24.6% of them reporting ever experiencing NVS. MSM reporting NVS at age 18 years or older were more likely to have had sex with an IDU [aPR = 4.40; 95% confidence interval (95% CI) 1.78–10.88] and exchanged sex for money or drugs (aPR = 2.52; 95% CI 1.17–5.43) in the past 12 months compared with those not reporting NVS. NVS for MSM less than 18 years of age was associated with exchanging sex for money or drugs. Conclusion:Effective interventions to raise awareness of NVS among MSM and to offer support for MSM who have experienced NVS are needed.


Travel Medicine and Infectious Disease | 2012

Rubella contact tracing associated with air travel.

Curi Kim; Pollyanna Chavez; Abbi Pierce; Andrew Murray; Molly Sander; Cynthia L. Kenyon; Ruta Sharangpani; Emily Abernathy; Joseph P. Icenogle; Preeta K. Kutty; Susan B. Redd; Kathleen Gallagher; John Neatherlin; Karen J. Marienau

This report reviews U.S. guidelines for the identification of persons exposed to rubella during air travel. In response to an individual with rubella who traveled on multiple flights, CDC conducted an airline contact investigation that was expanded beyond customary protocol to assess if current operating procedures are adequate. Of 250 potentially exposed airline passengers, 215 (86%) were contacted and none developed a rubella-like rash, arguing against the need to notify passengers beyond the standard protocol in most cases.


Aids Care-psychological and Socio-medical Aspects of Aids\/hiv | 2017

Willingness to distribute free rapid home HIV test kits and to test with social or sexual network associates among men who have sex with men in the United States

Akshay Sharma; Pollyanna Chavez; Robin MacGowan; A. D. McNaghten; Brian Mustanski; Laura Gravens; Arin Freeman; Patrick S. Sullivan

ABSTRACT Peer-driven HIV prevention strategies can be effective in identifying high-risk persons with undiagnosed infections. Besides individual self-testing, other potential uses of rapid home HIV test kits include distributing them, and testing with others within ones social or sexual networks. We sought to identify factors associated with the willingness to engage in these alternative activities among men who have sex with men (MSM) in the United States. From May to October 2014, we surveyed 828 HIV-negative or unknown status MSM about multiple aspects of rapid home HIV testing. A greater proportion indicated being likely to distribute free oral fluid (OF) tests compared to free finger-stick blood (FSB) tests (91% versus 79%), and almost three-fourths (72%) reported being likely to test with their friends or sex partners in the future. MSM not identifying as homosexual/gay were less willing to distribute OF tests, and those with lower educational attainment were more willing to distribute FSB tests. MSM unaware of their HIV status were less likely to report potentially testing with others using free rapid home HIV tests compared to those who were HIV-negative. Finally, MSM willing to self-test were more likely to report future test kit distribution, and those willing to distribute kits were more likely to report potentially testing with others. Engaging individuals with positive attitudes towards these strategies in prevention efforts could help increase HIV testing levels among MSM. A greater understanding of the potential public health impact of rapid home HIV test kits is necessary.


Clinical Infectious Diseases | 2018

Expanding Hospital Human Immunodeficiency Virus Testing in the Bronx, New York and Washington, District of Columbia: Results from the HPTN 065 Study

Bernard M. Branson; Pollyanna Chavez; Brett Hanscom; Elizabeth Greene; Laura McKinstry; Kate Buchacz; Geetha Beauchamp; Theresa Gamble; Barry S. Zingman; Edward E. Telzak; Tammey Naab; Lisa Fitzpatrick; Wafaa El-Sadr

Background Human immunodeficiency virus (HIV) testing is critical for both HIV treatment and prevention. Expanding testing in hospital settings can identify undiagnosed HIV infections. Methods To evaluate the feasibility of universally offering HIV testing during emergency department (ED) visits and inpatient admissions, 9 hospitals in the Bronx, New York and 7 in Washington, District of Columbia (DC) undertook efforts to offer HIV testing routinely. Outcomes included the percentage of encounters with an HIV test, the change from year 1 to year 3, and the percentages of tests that were HIV-positive and new diagnoses. Results From 1 February 2011 to 31 January 2014, HIV tests were conducted during 6.5% of 1621016 ED visits and 13.0% of 361745 inpatient admissions in Bronx hospitals and 13.8% of 729172 ED visits and 22.0% of 150655 inpatient admissions in DC. From year 1 to year 3, testing was stable in the Bronx (ED visits: 6.6% to 6.9%; inpatient admissions: 13.0% to 13.6%), but increased in DC (ED visits: 11.9% to 15.8%; inpatient admissions: 19.0% to 23.9%). In the Bronx, 0.4% (408) of ED HIV tests were positive and 0.3% (277) were new diagnoses; 1.8% (828) of inpatient tests were positive and 0.5% (244) were new diagnoses. In DC, 0.6% (618) of ED tests were positive and 0.4% (404) were new diagnoses; 4.9% (1349) of inpatient tests were positive and 0.7% (189) were new diagnoses. Conclusions Hospitals consistently identified previously undiagnosed HIV infections, but universal offer of HIV testing proved elusive.

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Elizabeth DiNenno

Centers for Disease Control and Prevention

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Emeka Oraka

Centers for Disease Control and Prevention

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Laura G. Wesolowski

Centers for Disease Control and Prevention

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Muazzam Nasrullah

Centers for Disease Control and Prevention

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A. D. McNaghten

Centers for Disease Control and Prevention

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Arin Freeman

Centers for Disease Control and Prevention

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Robin MacGowan

Centers for Disease Control and Prevention

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