Last data update: Dec 02, 2024. (Total: 48272 publications since 2009)
Records 1-30 (of 30 Records) |
Query Trace: Mixson-Hayden T[original query] |
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Hepatitis C virus infection and co-infection with HIV among persons who inject drugs in 10 U.S. cities-National HIV Behavioral Surveillance, 2018
Chapin-Bardales J , Asher A , Broz D , Teshale E , Mixson-Hayden T , Poe A , Handanagic S , Blanco C , Wejnert C . Int J Drug Policy 2024 104387 BACKGROUND: Characterizing acute and chronic hepatitis C virus (HCV) infection and HIV/HCV co-infection among persons who inject drugs (PWID) can inform elimination efforts. METHODS: During 2018 National HIV Behavioral Surveillance in 10 U.S. metropolitan statistical areas (MSAs), PWID were recruited using respondent-driven sampling and offered a survey, HIV testing, and HCV antibody and RNA testing. We examined prevalence and associated characteristics of HCV infection and HIV/HCV co-infection. Associations were assessed using log-linked Poisson regression models with robust standard errors accounting for clustering by recruitment chain and adjusting for MSA and network size. RESULTS: Overall, 44.2% had current HCV infection (RNA detected), with 3.9% classified as acute infection (HCV antibody non-reactive/RNA detected) and 40.3% as chronic (HCV antibody reactive/RNA detected). Four percent had HIV/HCV co-infection. Current HCV infection was significantly higher among PWID who were male, White, injected >1 time/day, shared syringes in past year, and shared injection equipment in past year. PWID who were transgender, injecting >5 years, and most often injected speedball (heroin and cocaine together) or stimulants alone were more likely to have HIV/HCV co-infection. Among PWID who never previously had HCV infection, 9.9% had acute HCV infection. Among PWID who started injecting ≤5 years ago, 41.5% had already acquired HCV infection. CONCLUSIONS: Acute and chronic HCV infections were substantial among a sample of PWID in 10 U.S. MSAs. Accessibility to HCV RNA testing, promoting safer practices, and intervening early with harm reduction programs for recent injection initiates will be critical to disease elimination efforts for PWID. |
HDV RNA Assays: Performance characteristics, clinical utility and challenges
Wedemeyer H , Leus M , Battersby TR , Glenn J , Gordien E , Kamili S , Kapoor H , Kessler HH , Lenz O , Lütgehetmann M , Mixson-Hayden T , Simon CO , Thomson M , Westman G , Miller V , Terrault N , Lampertico P . Hepatology 2023 Co-infection with hepatitis B virus (HBV) and hepatitis D virus (HDV) results in hepatitis D, the most severe form of chronic viral hepatitis, frequently leading to liver decompensation and hepatocellular carcinoma. Pegylated interferon alpha, the only treatment option for chronic hepatitis D for many years, has limited efficacy. New treatments are in advanced clinical development, with one recent approval. Diagnosis and antiviral treatment response monitoring are based on detection and quantification of HDV RNA. However, the development of reliable HDV RNA assays is challenged by viral heterogeneity (at least 8 different genotypes and several subgenotypes), intra-host viral diversity, rapid viral evolution, and distinct secondary structure features of HDV RNA. Different RNA extraction methodologies, primer/probe design for Nucleic Acid Tests, lack of automation, and overall dearth of standardization across testing laboratories contribute to substantial variability in performance characteristics of research-based and commercial HDV RNA assays. A WHO standard for HDV RNA, available for about 10 years, has been used by many laboratories to determine the limit of detection of their assays and facilitates comparisons of RNA levels across study centers. Here we review challenges for robust pan genotype HDV RNA quantification, discuss particular clinical needs and the importance of reliable HDV RNA quantification in the context of drug development and patient monitoring. We summarize distinct technical features and performance characteristics of available HDV RNA assays. Finally, we provide considerations for the use of HDV RNA assays in the context of drug development and patient monitoring. |
Hepatitis B vaccine delivered by microneedle patch: Immunogenicity in mice and rhesus macaques
Choi Y , Lee GS , Li S , Lee JW , Mixson-Hayden T , Woo J , Xia D , Prausnitz MR , Kamili S , Purdy MA , Tohme RA . Vaccine 2023 41 (24) 3663-3672 Vaccination against hepatitis B using a dissolving microneedle patch (dMNP) could increase access to the birth dose by reducing expertise needed for vaccine administration, refrigerated storage, and safe disposal of biohazardous sharps waste. In this study, we developed a dMNP to administer hepatitis B surface antigen (HBsAg) adjuvant-free monovalent vaccine (AFV) at doses of 5 µg, 10 µg, and 20 µg, and compared its immunogenicity to vaccination with 10 µg of standard monovalent HBsAg delivered by intramuscular (IM) injection either in an AFV format or as aluminum-adjuvanted vaccine (AAV). Vaccination was performed on a three dose schedule of 0, 3, and 9 weeks in mice and 0, 4, and 24 weeks in rhesus macaques. Vaccination by dMNP induced protective levels of anti-HBs antibody responses (≥10 mIU/ml) in mice and rhesus macaques at all three HBsAg doses studied. HBsAg delivered by dMNP induced higher anti-HBsAg antibody (anti-HBs) responses than the 10 µg IM AFV, but lower responses than 10 µg IM AAV, in mice and rhesus macaques. HBsAg-specific CD4+ and CD8+ T cell responses were detected in all vaccine groups. Furthermore, we analyzed differential gene expression profiles related to each vaccine delivery group and found that tissue stress, T cell receptor signaling, and NFκB signaling pathways were activated in all groups. These results suggest that HBsAg delivered by dMNP, IM AFV, and IM AAV have similar signaling pathways to induce innate and adaptive immune responses. We further demonstrated that dMNP was stable at room temperature (20 °C-25 °C) for 6 months, maintaining 67 ± 6 % HBsAg potency. This study provides evidence that delivery of 10 µg (birth dose) AFV by dMNP induced protective levels of antibody responses in mice and rhesus macaques. The dMNPs developed in this study could be used to improve hepatitis B birth dose vaccination coverage levels in resource limited regions to achieve and maintain hepatitis B elimination. |
Dried blood spot is the feasible matrix for detection of some but not all hepatitis B virus markers of infection.
Kikuchi M , Lindstrom P , Tejada-Strop A , Mixson-Hayden T , Kamili S , Sawabe M . BMC Res Notes 2022 15 (1) 287 OBJECTIVE: Use of dried blood spots (DBS) for detection of hepatitis B virus (HBV) markers of infection has the potential to facilitate diagnosis of HBV infection especially in resource-limited countries. The aim of this study was to evaluate the feasibility of DBS for detection of various markers of HBV infections. RESULTS: Fifty-four DBS samples were engineered from well-characterized plasma samples. All DBS samples were tested for HBsAg, total anti-HBc and HBV DNA, 20 of 54 samples were also tested for HBeAg using commercially available assays. HBsAg was detected in 24 of 25 (96%), HBV DNA in 22 of 25 (88%), total anti-HBc in all 9 (100%), and HBeAg in all 7 (100%) DBS samples. The average difference in HBV DNA levels between DBS eluates and corresponding plasma samples was 2.7 log(10) IU/mL. Fifteen DBS eluates positive for HBV DNA were sequenced and all of them belonged to HBV genotype A. Thirteen samples which were negative for all HBV markers showed HBeAg false positivity. Therefore, DBS is a reliable sample matrix for detection of HBsAg, total anti-HBc and HBV DNA, but not HBeAg. Further feasibility studies of DBS for diagnostic purposes and epidemiologic studies are warranted. |
In vitro characterization of six hepatitis B virus genotypes from clinical isolates using transfecting linear HBV genomes.
Zafrullah M , Vazquez C , Mixson-Hayden T , Purdy MA . J Gen Virol 2021 102 (11) Hepatitis B virus (HBV) infection is a global public health problem with about 257 million chronically infected people and over 887000 deaths annually. In this study, 32 whole HBV genomes of various genotypes were amplified from clinical isolates to create transfection clones. The clones were sequenced, and their biological properties characterized by transfecting linear HBV clones into HepG2 cells. We analysed the SPI and SPII promotor regions, X-gene, BCP/PC sequences, core, preS/S and HBV polymerase sequences. HBV clones analysed in this study revealed differential replication kinetics of viral nucleic acids and expression of proteins. Sequence analysis of HBV clones revealed mutations in preS1, preS2 and S genes; deletion and insertion and point mutations in BCP/PC region; including novel and previously reported mutations. Among the patient samples tested, HBV genotype B clones were more likely to have higher frequencies of mutations, while sub-genotype A1 and A2 clones tended to have fewer mutations. No polymerase drug resistant mutations were seen. HBeAg mutations were primarily in the BCP/PC region in genotype B, but core truncations were found in genotype E. S gene mutations affecting HBsAg expression and detection were seen in all genotypes except A2. Using an HBV clone with repetitive terminal sequences and a SapI restriction site allowed us to analyse HBV analyte production in cell culture and characterize the genetics of viral phenotypes using complete HBV genomes isolated from serum/plasma samples of infected patients. |
Hepatitis B virus mutant infections in hemodialysis patients: A case series
Apata IW , Nguyen DB , Khudyakov Y , Mixson-Hayden T , Rosenberg J , Zahn M , Greenko J , Clement E , Portney AE , Kulkarni PA , Comer M , Adams E , Kamili S , Patel PR , Moorman AC . Kidney Med 2019 1 (6) 347-353 Rationale & Objective: Hepatitis B virus (HBV) transmission in hemodialysis units has become a rare event since implementation of hemodialysis-specific infection control guidelines: performing hemodialysis for hepatitis B surface antigen (HBsAg)-positive patients in an HBV isolation room, vaccinating HBV-susceptible (HBV surface antibody and HBsAg negative) patients, and monthly HBsAg testing in HBV-susceptible patients. Mutations in HBsAg can result in false-negative HBsAg results, leading to failure to identify HBsAg seroconversion from negative to positive. We describe 4 unique cases of HBsAg seroconversion caused by mutant HBV infection or reactivation in hemodialysis patients. Study Design: Following identification of a possible HBsAg seroconversion and mutant HBV infection, public health investigations were launched to conduct further HBV testing of case patients and potentially exposed patients. A case patient was defined as a hemodialysis patient with suspected mutant HBV infection because of false-negative HBsAg testing results. Confirmed case patients had HBV DNA sequences demonstrating S-gene mutations. Setting & Participants: Case patients and patients potentially exposed to the case patient in the respective hemodialysis units in multiple US states. Results: 4 cases of mutant HBV infection in hemodialysis patients were identified; 3 cases were confirmed using molecular sequencing. Failure of some HBsAg testing platforms to detect HBV mutations led to delays in applying HBV isolation procedures. Testing of potentially exposed patients did not identify secondary transmissions. Limitations: Lack of access to information on past HBsAg testing platforms and results led to challenges in ascertaining when HBsAg seroconversion occurred and identifying and testing all potentially exposed patients. Conclusions: Mutant HBV infections should be suspected in patients who test HBsAg negative and concurrently test positive for HBV DNA at high levels. Dialysis providers should consider using HBsAg assays that can also detect mutant HBV strains for routine HBV testing. |
Integrated HIV surveillance finds recent adult hepatitis B virus (HBV) transmission and intermediate HBV prevalence among military in uncharacterized Caribbean country
O'Connor SM , Mixson-Hayden T , Ganova-Raeva L , Djibo DA , Brown M , Xia GL , Kamili S , Jacobs M , Dong M , Thomas AG , Bulterys M , Hale B . PLoS One 2019 14 (10) e0222835 BACKGROUND: Guyana expanded its HIV response in 2005 but the epidemiology of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections has not been characterized. METHODS: The 2011 Seroprevalence and Behavioral Epidemiology Risk Survey for HIV and STIs collected biologic specimens with demographic and behavioral data from a representative sample of Guyana military personnel. Diagnostics included commercial serum: HIV antibody; total antibody to hepatitis B core (anti-HBc); IgM anti-HBc; hepatitis B surface antigen (HBsAg); anti-HBs; antibody to HCV with confirmatory testing; and HBV DNA sequencing with S gene fragment phylogenetic analysis. Chi-square, p-values and prevalence ratios determined statistical significance. RESULTS: Among 480 participants providing serologic specimens, 176 (36.7%) tested anti-HBc-positive. Overall, 19 (4.0%) participants tested HBsAg-positive; 17 (89.5%) of the HBsAg-positive participants also had detectable anti-HBc, including 1 (5.3%) IgM anti-HBc-positive male. Four (6.8%) females with available HBV testing were HBsAg-positive, all aged 23-29 years. Sixteen (16, 84.2%) HBsAg-positive participants had sufficient specimen for DNA testing. All 16 had detectable HBV DNA, 4 with viral load >2x104IU/ml. Sequencing found: 12 genotype (gt) A1 with 99.9% genetic identity between 1 IgM anti-HBc-positive and 1 anti-HBc-negative; 2 gtD1; and 2 with insufficient specimen. No statistically significant associations between risk factors and HBV infection were identified. CONCLUSIONS: Integrated HIV surveillance identified likely recent adult HBV transmission, current HBV infection among females of reproductive age, moderate HBV infection prevalence (all gtA1 and D1), no HCV infections and low HIV frequency among Guyana military personnel. Integrated HIV surveillance helped characterize HBV and HCV epidemiology, including probable recent transmission, prompting targeted responses to control ongoing HBV transmission and examination of hepatitis B vaccine policies. |
Development of a World Health Organization International Reference Panel for different genotypes of hepatitis E virus for nucleic acid amplification testing.
Baylis SA , Hanschmann KO , Matsubayashi K , Sakata H , Roque-Afonso AM , Kaiser M , Corman VM , Kamili S , Aggarwal R , Trehanpati N , Gartner T , Thomson EC , Davis CA , da Silva Filipe A , Abdelrahman TT , Blumel J , Terao E . J Clin Virol 2019 119 60-67 BACKGROUND: Globally, hepatitis E virus (HEV) is a major cause of acute viral hepatitis. Epidemiology and clinical presentation of hepatitis E vary greatly by location and are affected by the HEV genotype. Nucleic acid amplification technique (NAT)-based assays are important for the detection of acute HEV infection as well for monitoring chronic cases of hepatitis E. OBJECTIVES: The aim of the study was to evaluate a panel of samples containing different genotypes of HEV for use in nucleic NAT-based assays. STUDY DESIGN: The panel of samples comprises eleven different members including HEV genotype 1a (2 strains), 1e, 2a, 3b, 3c, 3e, 3f, 4c, 4g as well as a human isolate related to rabbit HEV. Each laboratory assayed the panel members directly against the 1(st) World Health Organization (WHO) International Standard (IS) for HEV RNA (6329/10) which is based upon a genotype 3 a strain. RESULTS: The samples for evaluation were distributed to 24 laboratories from 14 different countries and assayed on three separate days. Of these, 23 participating laboratories returned a total of 32 sets of data; 17 from quantitative assays and 15 from qualitative assays. The assays used consisted of a mixture of in-house developed and commercially available assays. The results showed that all samples were detected consistently by the majority of participants, although in some cases, some samples were detected less efficiently. CONCLUSIONS: Based on the results of the collaborative study the panel (code number 8578/13) was established as the "1st International Reference Panel (IRP) for all HEV genotypes for NAT-based assays" by the WHO Expert Committee on Biological Standardization. This IRP will be important for assay validation and ensuring adequate detection of different genotypes and clinically important sub-genotypes of HEV. |
Hepatitis B and C virus infections transmitted through organ transplantation investigated by CDC, United States, 2014-2017
Bixler D , Annambholta P , Abara WE , Collier MG , Jones J , Mixson-Hayden T , Basavaraju SV , Ramachandran S , Kamili S , Moorman A . Am J Transplant 2019 19 (9) 2570-2582 We evaluated clinical outcomes among organ recipients with donor-derived hepatitis B virus (HBV) or hepatitis C virus (HCV) infections investigated by CDC from 2014-2017 in the United States. We characterized new HBV infections in organ recipients if donors tested negative for total anti-HBc, HBsAg and HBV DNA, and new recipient HCV infections if donors tested negative for anti-HCV and HCV RNA. Donor risk behaviors were abstracted from next-of-kin interviews and medical records. During 2014-2017, seven new recipient HBV infections associated with seven donors were identified; six (86%) recipients survived. At last follow-up, all survivors had functioning grafts and five (83%) had started antiviral therapy. Twenty new recipient HCV infections associated with nine donors were identified; 19 (95%) recipients survived. At last follow-up, 18 (95%) survivors had functioning grafts and 14 (74%) had started antiviral treatment. Combining donor next-of kin interviews and medical records, 11/16 (69%) donors had evidence of injection drug use and all met Public Health Service increased risk donor (IRD) criteria. IRD designation led to early diagnosis of recipient infection, and prompt implementation of therapy, likely reducing the risk of graft failure, liver disease and death. This article is protected by copyright. All rights reserved. |
Evaluation of performance characteristics of hepatitis B e antigen serologic assays
Mixson-Hayden T , Purdy MA , Ganova-Raeva L , McGovern D , Forbi JC , Kamili S . J Clin Virol 2018 109 22-28 BACKGROUND: Hepatitis B e antigen (HBeAg) is considered an indicator of high hepatitis B virus (HBV) replication. Performance characteristics of commercially available HBeAg assays have not been determined, thus it is unknown whether lack of HBeAg detection is because of test sensitivity or HBV basal core promoter and precore mutations. OBJECTIVES: We studied the correlation between HBeAg reactivity with HBV DNA levels in three commercially available HBeAg assays using 335 HBsAg and HBV DNA positive serum/plasma samples. STUDY DESIGN: Diagnostic sensitivity was determined by serial dilutions of a WHO HBeAg standard. The limit of HBeAg detection estimated through regression was 1 IU/mL (Centaur), 97 IU/mL (DiaSorin) and 129 IU/mL (Vitros). Of these 335 samples, enough sample volume remained in 253 samples for head-to-head comparison of the assays. RESULTS: 81 (32%), 41 (16%) and 36 (14%) of the samples were HBeAg positive by the Centaur, DiaSorin and Vitros assays, respectively. Compared to the FDA-approved Centaur assay the specificity of the other two assays was 98%, while sensitivity was 47% for the DiaSorin assay and 41% for the Vitros assay. Significant association was found between HBeAg positive samples and HBV DNA levels >20,000 IU/mL; 31% of HBeAg negative samples (Centaur) had HBV DNA levels >20,000 IU/mL, 26% of HBeAg positive samples had HBV DNA levels <20,000 IU/mL and 5 HBeAg positive samples had HBV DNA levels <2000 IU/mL. CONCLUSION: Discordance was seen between these HBeAg assays, indicating reliance on HBeAg alone as a marker of high HBV replication can be misleading. Detection and quantification of HBV DNA remains the accurate and reliable marker of HBV replication. |
Delta hepatitis: Towards improved diagnostics
Kamili S , Drobeniuc J , Mixson-Hayden T , Kodani M . Hepatology 2017 66 (6) 1716-1718 Hepatitis D virus (HDV), the etiologic agent of hepatitis D or delta hepatitis, is a unique human virus that requires the hepatitis B surface antigen (HBsAg) of hepatitis B virus (HBV) for its replication and to establish infection. HDV, the only member of its own separate genus, Deltavirus, is the smallest known infectious viral agent of humans.1 The HDV virion, which measures 35‐37 nm in diameter, contains a single‐stranded circular ∼1,700‐nucleotide RNA genome of negative polarity, which encloses only a single functional open reading frame encoding the sole viral protein, the hepatitis delta antigen (HDAg). The HDAg is associated with the genomic RNA to form a ribonucleoprotein complex which is encapsulated by a lipid envelope containing the small, middle, and large HBsAg proteins.2 HDV exhibits a high degree of genetic heterogeneity, with estimated mutation rates between 3 × 10–2 and 3 × 10–3 base substitutions per genomic site per year.1 The virus has a wide geographic distribution with eight distinct genotypes. HDV genotype 1 is the most common genotype, being prevalent in North America, Europe, the Middle East, and North Africa; genotypes 2 and 4 are found predominantly in East Asia; genotype 3 is found exclusively in the Amazon basin in South America; and genotypes 5‐8, also known as African genotypes, are predominantly found in West and central Africa.3 |
Hepatitis C virus transmission in a skilled nursing facility, North Dakota, 2013
Calles DL , Collier MG , Khudyakov Y , Mixson-Hayden T , VanderBusch L , Weninger S , Miller TK . Am J Infect Control 2016 45 (2) 126-132 BACKGROUND: From March-May 2013, 3 cases of acute hepatitis C virus (HCV) infection were diagnosed among elderly patients residing at the same skilled nursing facility (facility A) and who received health care at hospital X during their likely exposure period. METHODS: We performed HCV testing of at-risk populations; quasispecies analysis was performed to determine relatedness of HCV in persons with current infection. Infection control practice assessments were conducted at facility A and hospital X. Persons residing in facility A on September 9, 2013, were enrolled in a case-control study to identify risk factors for HCV infection. RESULTS: Forty-five outbreak-associated infections were identified. Thirty cases and 62 controls were enrolled in the case-control study. Only podiatry (odds ratio, 11.6; 95% confidence interval, 2.4-57.2) and international normalized ratio monitoring by phlebotomy (odds ratio, 6.7; 95% confidence interval, 1.7-26.6) at facility A were significantly associated with case status. Infection control lapses during podiatry and point-of-care testing procedures at facility A were identified. CONCLUSIONS: HCV transmission was confirmed among residents of facility A. The exact mode of transmission was not able to be identified, but infection control lapses were likely responsible. This outbreak highlights the importance of prompt reporting and investigation of incident HCV infection and the need for adherence to basic infection control procedures by health care personnel. |
Notes from the Field: Health Care-Associated Hepatitis A Outbreak - Texas, 2015
Wiseman R , Weil LM , Lozano C , Johnson TJ Jr , Jin S , Moorman AC , Foster MA , Mixson-Hayden T , Khudyakov Y , Kuhar DT , Graves J . MMWR Morb Mortal Wkly Rep 2016 65 (16) 425-426 On August 27-28, 2015, the Texas Department of State Health Services received calls from Fort Bend County and Harris County health departments requesting postexposure prophylaxis (PEP) recommendations for contacts of two nurses (patients A and B) with confirmed hepatitis A virus (HAV) infection. Both nurses had symptom onset during August 15-19 and worked for the same pediatric home health care agency in another jurisdiction. Because of the proximity of the onset dates, a common source exposure was suspected. The state and local health departments began an investigation to identify potentially exposed patients, their families, and other agency personnel; offer PEP; and identify the source of exposure. |
High hepatitis C virus (HCV) prevalence among men who have sex with men (MSM) in Vietnam and associated risk factors: 2010 Vietnam Integrated Behavioural and Biologic Cross-Sectional Survey
Nadol P , O'Connor S , Duong H , Mixson-Hayden T , Tram TH , Xia GL , Kaldor J , Law M , Nguyen T . Sex Transm Infect 2016 92 (7) 542-549 BACKGROUND: Hepatitis C virus (HCV) is an increasing health issue among key populations such as men who have sex with men (MSM). We sought to assess the burden of and risk factors for HCV among MSM in Vietnam. METHODS: We analysed behavioural and demographic data and stored specimens from MSM surveyed in four provinces through Vietnam's 2009-2010 Integrated Biologic and Behavioural Survey, which used probability-based, respondent-driven sampling. Commercial hepatitis B surface antigen (HBsAg) and HCV/antibody (HCV Ag/Ab) testing were performed on archived sera with follow-up PCR for HCV RNA and genotype determination. RESULTS: Among the 1588 MSM surveyed, the median (range) frequency, by province, of HCV Ag/Ab detection was 28.4% (13.7%-38.8%); 84.5% (83.1%-100%) among HIV-infected and 21.9% (8.9%-28.2%) among HIV-uninfected. HCV prevalence was higher in northern Hanoi and Hai Phong provinces than in southern Ho Chi Minh City and Chan Tho provinces. Among a convenience sample of 67 HCV Ag/Ab+ MSM, 67.2% were HCV RNA+; of 41 genotyped, 73.2% were genotype 1. HBsAg prevalence varied from 8.5% to 27.4%. In the multivariable logistic regression analysis, being HIV-infected (adjusted OR (aOR) 19.0; 7.0-51.9), ever having used injected drugs (aOR 4.4; 1.6-12.4) and age >25 years were significant risk factors for testing HCV Ag/Ab+. CONCLUSIONS: HCV infection in Vietnam appears to be high among MSM, particularly among HIV-infected MSM, with a north-south gradient. Given overlapping risk behaviours and associations between HCV and HIV, integrating HIV and HCV programme services to prevent both HIV and HCV transmission among MSM is indicated. |
Notes from the Field: Hepatitis C Outbreak in a Dialysis Clinic - Tennessee, 2014.
Muleta D , Kainer MA , Moore-Moravian L , Wiese A , Ward J , McMaster S , Nguyen D , Forbi JC , Mixson-Hayden T , Collier M . MMWR Morb Mortal Wkly Rep 2016 64 1386-7 Outbreaks of hepatitis C virus (HCV) infections can occur among hemodialysis patients when recommended infection control practices are not followed (1). On January 30, 2014, a dialysis clinic in Tennessee identified acute HCV in a patient (patient A) during routine screening and reported it to the Tennessee Department of Health. Patient A had enrolled in the dialysis clinic in March 2010 and had annually tested negative for HCV (including a last HCV test on December 19, 2012), until testing positive for HCV antibodies (anti-HCV) on December 18, 2013 (confirmed by a positive HCV nucleic acid amplification test). Patient A reported no behavioral risk factors, but did have multiple health care exposures. |
Fatal Accelerated Cirrhosis after Imported HEV Genotype 4 Infection.
Perumpail RB , Ahmed A , Higgins JP , So SK , Cochran JL , Drobeniuc J , Mixson-Hayden TR , Teo CG . Emerg Infect Dis 2015 21 (9) 1679-81 Hepatitis E is a viral hepatitide that is endemic in many developing countries. In its classic form, it results from ingesting fecally contaminated water that carries hepatitis E virus (HEV), and it frequently resolves without treatment. When hepatitis E is imported to the United States, it originates mainly from persons who have acquired HEV genotype 1 infection from South Asia (1). We report imported HEV genotype 4 infection (Technical Appendix Figure, panel A) in a patient during which cirrhosis and fatal hepatic decompensation ensued. | The patient was a 68-year-old man of Chinese ethnicity who had been a California resident since 1985. He sought treatment for mild jaundice in April 2013 in Hong Kong, where he had been staying for 7 weeks. Sixteen years before, he had undergone orthotopic liver transplantation at Stanford University Medical Center (Palo Alto, California, USA) for hepatitis B cirrhosis. Since then, he had received entecavir and tacrolimus for maintenance and had been vaccinated against hepatitis A virus. Until his current illness, routine liver function tests had not indicated hepatic dysfunction (values in November 2012: alanine aminotransferase 2 IU/L, aspartate aminotransferase 24 IU/L, alkaline phosphatase 67 IU/L, total bilirubin 0.5 mg/dL). |
Performance of ARCHITECT HCV core antigen test with specimens from US plasma donors and injecting drug users
Mixson-Hayden T , Dawson GJ , Teshale E , Le T , Cheng K , Drobeniuc J , Ward J , Kamili S . J Clin Virol 2015 66 15-8 BACKGROUND: Hepatitis C virus (HCV) core antigen is a serological marker of current HCV infection. OBJECTIVES: The aim of this study was mainly to evaluate the performance characteristics of the ARCHITECT HCV core antigen assay with specimens from US plasma donors and injecting drug users. STUDY DESIGN: A total of 551 serum and plasma samples with known anti-HCV and HCV RNA status were tested for HCV core antigen using the Abbott ARCHITECT HCV core antigen test. RESULTS: HCV core antigen was detectable in 100% of US plasma donor samples collected during the pre-seroconversion phase of infection (anti-HCV negative/HCV RNA positive). Overall sensitivity of the HCV core antigen assay was 88.9-94.3% in samples collected after seroconversion. The correlation between HCV core antigen and HCV RNA titers was 0.959. CONCLUSIONS: HCV core antigen testing may be reliably used to identify current HCV infection. |
Variability of hepatitis E serologic assays in a pediatric liver transplant recipient: challenges to diagnosing hepatitis E virus infection in the United States
Sue PK , Pisanic N , Heaney CD , Mixson-Hayden T , Kamili S , Nelson K , Schwarz KB , Forman M , Valsamakis A , Ticehurst J , Karnsakul W . Transpl Infect Dis 2015 17 (2) 284-8 Hepatitis E virus (HEV) is an emerging cause of viral hepatitis among immunocompromised individuals in developed countries. Yet the diagnosis of HEV infection in the United States remains challenging, because of the variable sensitivity and specificity of currently available tests, and the lack of a US Food and Drug Administration-approved test. We report a case of multiple discordant HEV serology results in a pediatric liver transplant recipient with idiopathic hepatitis, and review the challenges to diagnosis of HEV infection in the United States. |
Disparate detection outcomes for anti-HCV IgG and HCV RNA in dried blood spots.
Tejada-Strop A , Drobeniuc J , Mixson-Hayden T , Forbi JC , Le NT , Li L , Mei J , Terrault N , Kamili S . J Virol Methods 2014 212c 66-70 Dried blood spots (DBS) expedite the collection, storage and shipping of blood samples, thereby facilitating large-scale serologic studies. We evaluated the sensitivity of anti-HCV IgG testing and HCV-RNA quantitation using freshly prepared and stored DBS derived from HCV-infected patients. Protocols for elution were optimized using DBS prepared from plasma of 52 HCV-infected persons and 51 uninfected persons (control DBS), then applied to DBS from 33 chronic hepatitis C patients that had been stored at -20 degrees C for 5 years (stored DBS). Control and stored DBS, and their corresponding plasma, were processed for anti-HCV IgG testing using the VITROS chemiluminescence assay (CIA) and the HCV 3.0 enzyme immunoassay (EIA) (Ortho-Clinical Diagnostics), and for HCV RNA quantitation by quantitative (q) RT-PCR. HCV genotyping was conducted by nucleotide sequencing. The sensitivity of CIA and EIA in control DBS was 92% and 90%, respectively, compared to 100% and 97%, respectively, in stored DBS. The sensitivity of HCV RNA detection was 88% in control DBS, compared to 36% in stored DBS. Specificity was 100% for all the assays in both control and stored DBS. Genotypes 1, 2 and 3 were detected in 16 (62%), 6 (23.1%), and 4 (15.3%) samples, respectively. Sequences generated from DBS and their corresponding plasma samples were identical. Whereas the sensitivity of anti-HCV IgG detection in stored DBS was equivalent to that in recently prepared DBS, the sensitivity of HCV RNA detection was markedly lower in stored DBS compared to recently prepared DBS. Stored DBS may be reliably used for anti-HCV detection but for HCV-RNA-based testing freshly prepared DBS is preferable to stored DBS. |
Rapid and sensitive approach to simultaneous detection of genomes of hepatitis A, B, C, D and E viruses.
Kodani M , Mixson-Hayden T , Drobeniuc J , Kamili S . J Clin Virol 2014 61 (2) 260-4 BACKGROUND: Five viruses have been etiologically associated with viral hepatitis. Nucleic acid testing (NAT) remains the gold standard for diagnosis of viremic stages of infection. NAT methodologies have been developed for all hepatitis viruses; however, a NAT-based assay that can simultaneously detect all five viruses is not available. OBJECTIVES: We designed TaqMan card-based assays for detection of HAV RNA, HBV DNA, HCV RNA, HDV RNA and HEV RNA. STUDY DESIGN: The performances of individual assays were evaluated on TaqMan Array Cards (TAC) for detecting five viral genomes simultaneously. Sensitivity and specificity were determined by testing 329 NAT-tested clinical specimens. RESULTS: All NAT-positive samples for HCV (n=32), HDV (n=28) and HEV (n=14) were also found positive in TAC (sensitivity, 100%). Forty-three of 46 HAV-NAT positive samples were also positive in TAC (sensitivity, 94%), while 36 of 39 HBV-NAT positive samples were positive (sensitivity, 92%). No false-positives were detected for HBV (n=32), HCV (n=36), HDV (n=30), and HEV (n=31) NAT-negative samples (specificity 100%), while 38 of 41 HAV-NAT negative samples were negative by TAC (specificity 93%). CONCLUSIONS: TAC assay was concordant with corresponding individual NATs for hepatitis A-E viral genomes and can be used for their detection simultaneously. The TAC assay has potential for use in hepatitis surveillance, for screening of donor specimens and in outbreak situations. Wider availability of TAC-ready assays may allow for customized assays, for improving acute jaundice surveillance and for other purposes for which there is need to identify multiple pathogens rapidly. |
Characterization of the bacterial communities of life stages of free living lone star ticks (Amblyomma americanum)
Williams-Newkirk AJ , Rowe LA , Mixson-Hayden TR , Dasch GA . PLoS One 2014 9 (7) e102130 The lone star tick (Amblyomma americanum) is an abundant and aggressive biter of humans, domestic animals, and wildlife in the southeastern-central USA and an important vector of several known and suspected zoonotic bacterial pathogens. However, the biological drivers of bacterial community variation in this tick are still poorly defined. Knowing the community context in which tick-borne bacterial pathogens exist and evolve is required to fully understand the ecology and immunobiology of the ticks and to design effective public health and veterinary interventions. We performed a metagenomic survey of the bacterial communities of questing A. americanum and tested 131 individuals (66 nymphs, 24 males, and 41 females) from five sites in three states. Pyrosequencing was performed with barcoded eubacterial primers targeting variable 16S rRNA gene regions 5-3. The bacterial communities were dominated by Rickettsia (likely R. amblyommii) and an obligate Coxiella symbiont, together accounting for 6.7-100% of sequences per tick. DNAs from Midichloria, Borrelia, Wolbachia, Ehrlichia, Pseudomonas, or unidentified Bacillales, Enterobacteriaceae, or Rhizobiales groups were also detected frequently. Wolbachia and Midichloria significantly co-occurred in Georgia (p<0.00001), but not in other states. The significance of the Midichloria-Wolbachia co-occurrence is unknown. Among ticks collected in Georgia, nymphs differed from adults in both the composition (p = 0.002) and structure (p = 0.002) of their bacterial communities. Adults differed only in their community structure (p = 0.002) with males containing more Rickettsia and females containing more Coxiella. Comparisons among adult ticks collected in New York and North Carolina supported the findings from the Georgia collection despite differences in geography, collection date, and sample handling, implying that the differences detected are consistent attributes. The data also suggest that some members of the bacterial community change during the tick life cycle and that some sex-specific attributes may be detectable in nymphs. |
Hepatitis B virus and hepatitis C virus infections in United States-bound refugees from Asia and Africa
Mixson-Hayden T , Lee D , Ganova-Raeva L , Drobeniuc J , Stauffer WM , Teshale E , Kamili S . Am J Trop Med Hyg 2014 90 (6) 1014-20 The aim of this study was to determine the prevalence of active hepatitis B and C virus infections among refugees from various countries in Africa and Asia. Pre-admission serum samples collected during 2002-2007 from refugees originating from Bhutan (N = 755), Myanmar (N = 1076), Iraq (N = 1137), Laos (N = 593), Thailand (N = 622), and Somalia (N = 707) were tested for hepatitis B virus (HBV) DNA and hepatitis C virus (HCV) RNA. The HBV DNA (genotypes A, B, C, and G) was detected in 12.1% of samples negative for anti-HBs. Highest HBV prevalence was found among Hmong; lowest among Bhutanese. The HCV RNA (genotypes 1a, 1b, 1c, 3b, 6n, and 6m) was detected in 1.3% of the samples. Highest HCV prevalence was found among Hmong from Thailand; lowest among Iraqis. Screening specific refugee groups at high risk for viral hepatitis infections will identify infected individuals who could benefit from referral to care and treatment and prevent further transmissions. |
One-step real-time PCR assay for detection and quantitation of hepatitis D virus RNA.
Kodani M , Martin A , Mixson-Hayden T , Drobeniuc J , Gish RR , Kamili S . J Virol Methods 2013 193 (2) 531-5 Hepatitis D virus (HDV) is a defective virus which requires hepatitis B virus (HBV) surface antigen (HBsAg) for its assembly. Hepatitis B infected individuals co-infected or superinfected with HDV often present with more severe hepatitis, progress faster to liver disease, and have a higher mortality rate than individuals infected with HBV alone. Currently, there are no commercially available clinical tests for the detection and quantitation of HDV RNA in the United States. A one-step TaqMan quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assay was developed for detection of HDV RNA, designing primers located in the region located just downstream from the HDV antigen gene. The assay has the potential to detect all eight HDV genotypes. A quantifiable synthetic RNA control was also developed for use in the determination of HDV RNA titers in clinical samples. The limit of detection of this assay is 7.5x102 HDV RNA copies/ml with a dynamic range of six logs. Most clinical specimens tested (40/41) fell within the linear range of the assay. The median HDV RNA titer of the tested specimens was 6.24x106 copies/ml, with a range of 8.52x103 to 1.79x109 copies/ml. Out of 132 anti-HDV-positive specimens 41 (31.1%) were positive for HDV RNA. |
Historical shifts in Brazilian P. falciparum population structure and drug resistance alleles.
Griffing SM , Viana GM , Mixson-Hayden T , Sridaran S , Alam MT , de Oliveira AM , Barnwell JW , Escalante AA , Povoa MM , Udhayakumar V . PLoS One 2013 8 (3) e58984 Previous work suggests that Brazilian Plasmodium falciparum has limited genetic diversity and a history of bottlenecks, multiple reintroductions due to human migration, and clonal expansions. We hypothesized that Brazilian P. falciparum would exhibit clonal structure. We examined isolates collected across two decades from Amapa, Rondonia, and Para state (n = 190). By examining more microsatellites markers on more chromosomes than previous studies, we hoped to define the extent of low diversity, linkage disequilibrium, bottlenecks, population structure, and parasite migration within Brazil. We used retrospective genotyping of samples from the 1980s and 1990s to explore the population genetics of SP resistant dhfr and dhps alleles. We tested an existing hypothesis that the triple mutant dhfr mutations 50R/51I/108N and 51I/108N/164L developed in southern Amazon from a single origin of common or similar parasites. We found that Brazilian P. falciparum had limited genetic diversity and isolation by distance was rejected, which suggests it underwent bottlenecks followed by migration between sites. Unlike Peru, there appeared to be gene flow across the Brazilian Amazon basin. We were unable to divide parasite populations by clonal lineages and pairwise FST were common. Most parasite diversity was found within sites in the Brazilian Amazon, according to AMOVA. Our results challenge the hypothesis that triple mutant alleles arose from a single lineage in the Southern Amazon. SP resistance, at both the double and triple mutant stages, developed twice and potentially in different regions of the Brazilian Amazon. We would have required samples from before the 1980s to describe how SP resistance spread across the basin or describe the complex internal migration of Brazilian parasites after the colonization efforts of past decades. The Brazilian Amazon basin may have sufficient internal migration for drug resistance reported in any particular region to rapidly spread to other parts of basin under similar drug pressure. |
Laboratory-based surveillance for hepatitis E virus infection, United States, 2005-2012
Drobeniuc J , Greene-Montfort T , Le NT , Mixson-Hayden TR , Ganova-Raeva L , Dong C , Novak RT , Sharapov UM , Tohme RA , Teshale E , Kamili S , Teo CG . Emerg Infect Dis 2013 19 (2) 218-22 To investigate characteristics of hepatitis E cases in the United States, we tested samples from persons seronegative for acute hepatitis A and B whose clinical specimens were referred to the Centers for Disease Control and Prevention during June 2005-March 2012 for hepatitis E virus (HEV) testing. We found that 26 (17%) of 154 persons tested had hepatitis E. Of these, 15 had not recently traveled abroad (nontravelers), and 11 had (travelers). Compared with travelers, nontravelers were older (median 61 vs. 32 years of age) and more likely to be anicteric (53% vs. 8%); the nontraveler group also had fewer persons of South Asian ethnicity (7% vs. 73%) and more solid-organ transplant recipients (47% vs. 0). HEV genotype 3 was characterized from 8 nontravelers and genotypes 1 or 4 from 4 travelers. Clinicians should consider HEV infection in the differential diagnosis of hepatitis, regardless of patient travel history. |
Presence, genetic variability, and potential significance of "Candidatus Midichloria mitochondrii" in the lone star tick Amblyomma americanum.
Williams-Newkirk AJ , Rowe LA , Mixson-Hayden TR , Dasch GA . Exp Appl Acarol 2012 58 (3) 291-300 We used next generation sequencing to detect the bacterium "Candidatus Midichloria mitochondrii" for the first time in lone star ticks (Amblyomma americanum) from the eastern United States. 177 individuals and 11 tick pools from seven sites in four states were tested by pyrosequencing with barcoded 16S rRNA gene eubacterial primers targeting variable regions 5-3. Average infection prevalence was 0.15 across all surveyed populations (range 0-0.29) and only the site with the smallest sample size (n = 5) was negative. Three genotypes differing by 2.6-4.1 % in a 271 bp region of 16S rRNA gene were identified. Two variants co-occurred in sites in North Carolina and New York, but were not observed in the same tick at those sites. The third genotype was found only in Georgia. Phylogenetic analysis of this fragment indicated that the three variants are more closely related to "Candidatus Midichloria mitochondrii" genotypes from other tick species than to each other. This variation suggests that multiple independent introductions occurred in A. americanum which may provide insight into bacterial spread within its ecosystem and parasitism on this tick. Whether the presence of this bacterium affects acquisition or maintenance of other pathogens and symbionts in A. americanum or the survival, biology and evolution of the tick itself is unknown. |
Suppression of alpha interferon signaling by hepatitis E virus
Dong C , Mohammad Z , Mixson-Hayden T , Dai X , Liang J , Meng J , Kamili S . Hepatology 2011 55 (5) 1324-32 The interferon (IFN) system is integral to the host response against viruses to which many viruses have developed strategies to overcome its antiviral effects. The effects of hepatitis E virus (HEV), the causative agent of hepatitis E, on IFN signaling have not been investigated primarily because of the non-availability of an efficient in vitro culture system or small animal models of infection. Herein, we report the generation of A549 cell lines persistently infected with genotype 3 HEV, designated as HEV-A549 cells and the effects HEV has on IFN-alpha-mediated Janus kinase-signal transducer and activator of transcription (JAK-STAT) signaling. Treatment of HEV-A549 cells with 250, 500, and 1000 Units/ml of IFN-alpha for 72 hours showed dose-dependant reduction of HEV RNA levels by 10%, 20%, and 50% respectively. IFN-alpha-stimulated genes coding for the antiviral proteins, dsRNA-activated protein kinase (PKR) and 2',5'-oligoadenylate synthetase(2,5-OAS), were down-regulated in IFN-alpha-treated HEV-A549 cells. HEV infection also prevented IFN-alpha-induced phosphorylation of STAT1. Regulation of STAT1 by HEV was specific, as phosphorylation of STAT2, tyrosine kinase (Tyk) 2, and Jak1 by IFN-alpha were unaltered. Additionally, STAT1 levels were markedly increased in HEV-A549 cells compared to naive A549 cells. Furthermore, binding of HEV ORF3 protein to STAT1 in HEV-A549 cells was observed. HEV ORF3 protein alone inhibited IFN-alpha-induced phosphorylation of STAT1 and down-regulated the IFN-alpha-stimulated genes encoding PKR, 2,5-OAS and myxovirus resistance A (MxA). Conclusions: HEV inhibits IFN-alpha signaling through the regulation of STAT1 phosphorylation in A549 cells. These findings have implications for the development of new strategies against hepatitis E. (HEPATOLOGY 2011.) |
South American Plasmodium falciparum after the malaria eradication era: clonal population expansion and survival of the fittest hybrids.
Griffing SM , Mixson-Hayden T , Sridaran S , Alam MT , McCollum AM , Cabezas C , Marquino Quezada W , Barnwell JW , Macedo De Oliveira A , Lucas C , Arrospide N , Escalante AA , Bacon DJ , Udhayakumar V . PLoS One 2011 6 (9) e23486 Malaria has reemerged in many regions where once it was nearly eliminated. Yet the source of these parasites, the process of repopulation, their population structure, and dynamics are ill defined. Peru was one of malaria eradication's successes, where Plasmodium falciparum was nearly eliminated for two decades. It reemerged in the 1990s. In the new era of malaria elimination, Peruvian P. falciparum is a model of malaria reinvasion. We investigated its population structure and drug resistance profiles. We hypothesized that only populations adapted to local ecological niches could expand and repopulate and originated as vestigial populations or recent introductions. We investigated the genetic structure (using microsatellites) and drug resistant genotypes of 220 parasites collected from patients immediately after peak epidemic expansion (1999-2000) from seven sites across the country. The majority of parasites could be grouped into five clonal lineages by networks and AMOVA. The distribution of clonal lineages and their drug sensitivity profiles suggested geographic structure. In 2001, artesunate combination therapy was introduced in Peru. We tested 62 parasites collected in 2006-2007 for changes in genetic structure. Clonal lineages had recombined under selection for the fittest parasites. Our findings illustrate that local adaptations in the post-eradication era have contributed to clonal lineage expansion. Within the shifting confluence of drug policy and malaria incidence, populations continue to evolve through genetic outcrossing influenced by antimalarial selection pressure. Understanding the population substructure of P. falciparum has implications for vaccine, drug, and epidemiologic studies, including monitoring malaria during and after the elimination phase. |
Pfmdr1 amplification and fixation of chloroquine resistant pfcrt alleles in Venezuela
Griffing S , Syphard L , Sridaran S , McCollum AM , Mixson-Hayden T , Vinayak S , Villegas L , Barnwell JW , Escalante AA , Udhayakumar V . Antimicrob Agents Chemother 2010 54 (4) 1572-9 Molecular tools are valuable for determining evolutionary history and the prevalence of drug-resistant malaria parasites. These tools have helped to predict decreased sensitivity to antimalarials and fixation of multidrug resistant genotypes in some regions. In order to assess how historical drug policies impacted Venezuelan Plasmodium falciparum, we examined molecular changes to genes associated with drug resistance. We examined pfmdr1 and pfcrt in samples from Sifontes, Venezuela and integrated our findings with earlier work describing dhfr and dhps in these samples. We characterized pfmdr1 genotypes and copy number variation, pfcrt genotypes, and proximal microsatellites in 93 samples originating from 2003-2004 surveillance. Multicopy pfmdr1 was found in 12% of the samples. Two pfmdr1 alleles, Y184F/N1042D/D1246Y (37%) and Y184F/S1034C/N1042D/D1246Y (63%), were found. These alleles share ancestry and no evidence of strong selective pressure on mutations was found. Chloroquine resistant pfcrt alleles are fixed with two alleles: StctVMNT (91%) and SagtVMNT (9%). These alleles are associated with strong selection. There was also an association between pfcrt, pfmdr1, dhfr, and dhps genotypes/haplotypes. Duplication of pfmdr1 suggests a potential shift in mefloquine sensitivity in this region, which warrants further study. A bottleneck occurred in P. falciparum in Sifontes and multidrug resistant genotypes are present. This population could be targeted for malaria elimination programs to prevent the possible spread of multidrug resistant parasites. |
Evidence of selective sweeps in genes conferring resistance to chloroquine and pyrimethamine in Plasmodium falciparum within India
Mixson-Hayden T , Jain V , McCollum AM , Poe A , Nagpal AC , Dash AP , Stiles JK , Udhayakumar V , Singh N . Antimicrob Agents Chemother 2009 54 (3) 997-1006 Treatment of Plasmodium falciparum is complicated by the emergence and spread of parasite resistance to many of the first line drugs used to treat malaria. Anti-malarial drug resistance has been associated with specific point mutations in several genes, suggesting that these single nucleotide polymorphisms can be useful in tracking the emergence of drug resistance. In India, P. falciparum can manifest itself as asymptomatic, mild, or severe malaria, with or without cerebral involvement. We tested whether chloroquine and antifolate drug resistant genotypes would be more commonly associated with cases of cerebral malaria than with cases of mild malaria in the province of Jabalpur, India by genotyping the genes dhps, dhfr, pfmdr-1, and pfcrt using pyrosequencing, direct sequencing, and real time PCR. Further, we used microsatellites surrounding the genes to determine the origins and spread of the drug resistant genotypes in this area. Resistance to chloroquine was essentially fixed with 95% of the isolates harboring the pfcrt K76T mutation. Resistant genotypes of dhfr, dhps, and pfmdr-1 were found in 94%, 17%, and 77% of the isolates, respectively. Drug resistant genotypes were equally likely to be associated with cerebral malaria as they were with cases of mild malaria. We found evidence of a selective sweep in pfcrt and, to a lesser degree, dhfr, indicating high levels of resistance to chloroquine and evolving resistance to pyrimethamine. Microsatellites surrounding pfcrt indicate that the resistant genotypes (SVMNT) were most similar to those found in Papua New Guinea. |
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