[Show abstract][Hide abstract] ABSTRACT: Chronic liver infection by hepatitis C virus (HCV) is a major public health concern. Despite partly successful treatment options, several aspects of intrahepatic HCV infection dynamics are still poorly understood, including the preferred mode of viral propagation, as well as the proportion of infected hepatocytes. Answers to these questions have important implications for the development of therapeutic interventions. In this study, we present methods to analyze the spatial distribution of infected hepatocytes obtained by single cell laser capture microdissection from liver biopsy samples of patients chronically infected with HCV. By characterizing the internal structure of clusters of infected cells, we are able to evaluate hypotheses about intrahepatic infection dynamics. We found that individual clusters on biopsy samples range in size from [Formula: see text] infected cells. In addition, the HCV RNA content in a cluster declines from the cell that presumably founded the cluster to cells at the maximal cluster extension. These observations support the idea that HCV infection in the liver is seeded randomly (e.g. from the blood) and then spreads locally. Assuming that the amount of intracellular HCV RNA is a proxy for how long a cell has been infected, we estimate based on models of intracellular HCV RNA replication and accumulation that cells in clusters have been infected on average for less than a week. Further, we do not find a relationship between the cluster size and the estimated cluster expansion time. Our method represents a novel approach to make inferences about infection dynamics in solid tissues from static spatial data.
[Show abstract][Hide abstract] ABSTRACT: IMPORTANCE New data and antiretroviral regimens expand treatment choices in resource-rich settings and warrant an update of recommendations to treat adults infected with human immunodeficiency virus (HIV). OBJECTIVE To provide updated treatment recommendations for adults with HIV, emphasizing when to start treatment; what treatment to start; the use of laboratory monitoring tools; and managing treatment failure, switches, and simplification. DATA SOURCES, STUDY SELECTION, AND DATA SYNTHESIS An International Antiviral Society–USA panel of experts in HIV research and patient care considered previous data and reviewed new data since the 2012 update with literature searches in PubMed and EMBASE through June 2014. Recommendations and ratings were based on the quality of evidence and consensus. RESULTS Antiretroviral therapy is recommended for all adults with HIV infection. Evidence for benefits of treatment and quality of available data increase at lower CD4 cell counts. Recommended initial regimens include 2 nucleoside reverse transcriptase inhibitors (NRTIs; abacavir/lamivudine or tenofovir disoproxil fumarate/emtricitabine) and a third single or boosted drug, which should be an integrase strand transfer inhibitor (dolutegravir, elvitegravir, or raltegravir), a nonnucleoside reverse transcriptase inhibitor (efavirenz or rilpivirine) or a boosted protease inhibitor (darunavir or atazanavir). Alternative regimens are available. Boosted protease inhibitor monotherapy is generally not recommended, but NRTI-sparing approaches may be considered. New guidance for optimal timing of monitoring of laboratory parameters is provided. Suspected treatment failure warrants rapid confirmation, performance of resistance testing while the patient is receiving the failing regimen, and evaluation of reasons for failure before consideration of switching therapy. Regimen switches for adverse effects, convenience, or to reduce costs should not jeopardize antiretroviral potency. CONCLUSIONS AND RELEVANCE After confirmed diagnosis of HIV infection, antiretroviral therapy should be initiated in all individuals who are willing and ready to start treatment. Regimens should be selected or changed based on resistance test results with consideration of dosing frequency, pill burden, adverse toxic effect profiles, comorbidities, and drug interactions.
JAMA The Journal of the American Medical Association 07/2014; 312(4):410-25. · 29.98 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background & Aims: The contribution of humoral immune responses to spontaneous control of Hepatitis C virus (HCV) infection remains unclear. We assessed nAb responses during acute HCV infection to determine whether infection outcome is associated with the neutralizing antibody (nAb) response, specifically its timing or breadth (neutralization of multiple genotype-matched variants). Methods: A representative genotype 1 HCV pseudoparticle (HCVpp) library, consisting of 19 genetically-distinct genotype 1 HCVpp that comprise the natural variability of genotype 1 E1E2 sequences, was used to assess anti-genotype 1 nAb responses during acute infection in at-risk persons followed prospectively. Neutralization of individual library HCVpp by the last viremic plasma sample obtained before clearance was compared to either one-year post-initial viremia or clearance time-matched specimens obtained from subjects developing persistent infection. Results: In persistently infected persons nAb responses were delayed then progressively broadened whereas in persons who controlled viremia broader responses were detected early and contracted after clearance of viremia. Surprisingly, the breadth of anti-genotype 1 nAb responses was not dependent upon subjects' infection genotype. Also, individual library HCVpp neutralization sensitivity was not associated with any known E2 sequence determinants. Interestingly, two single nucleotide polymorphisms in the HLA-DQ locus were associated with nAb breadth. Conclusions: Taken together, these data demonstrate that control of HCV infection is associated with more rapid development of a broad nAb response, independent of the infection viral genotype, providing further evidence for the role of nAb in controlling HCV infection and the potential benefit of generating broad anti-HCV nAb responses by vaccination. (Hepatology 2014;).
[Show abstract][Hide abstract] ABSTRACT: The prevalence of hepatitis C viral (HCV) infection in sub-Saharan Africa remains unclear. We tested 1000 individuals from Rakai Uganda with the Ortho v3.0 HCV ELISA. All serologically positive samples were tested for HCV RNA. 7.6%(76/1000) subjects were HCV antibody positive, none were confirmed by detection of HCV RNA.
[Show abstract][Hide abstract] ABSTRACT: To confirm previously-identified polymorphisms in HAVCR1 that were associated with persistent hepatitis C virus (HCV) infection in individuals of African and of European descent, we studied 165 African-descent and 635 European-descent subjects. Since the association only confirmed in African-descent subjects (rs6880859, OR 2.42, P=0.01), we then used 379 African-descent subjects (142 with spontaneous HCV clearance) to fine map HAVCR1. rs111511318 was strongly associated with HCV persistence after adjusting for IL28B and HLA (adjusted P=8.8 x 10(-4)) as was one 81 kilobase haplotype (adjusted P=0.0006). The HAVCR1 genomic region is an independent genetic determinant of HCV persistence in African-descent subjects.
The Journal of Infectious Diseases 08/2013; · 5.85 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Interferon lambda 4 protein can be generated in IFNL4-ΔG carriers, but not IFNL4-TT homozygotes. We studied 890 anti-hepatitis C virus (HCV) positive participants in the Women's Interagency HIV Study. Among African Americans (n=555), HCV was more often cleared for those with genotype IFNL4-TT/TT (32.6%; odds ratio (OR), 3.59; p=3.3x10(-5)) than IFNL4-TT/ΔG (11.3%; OR, 0.95; p=0.86) or IFNL4-ΔG/ΔG (11.9%; referent). Pooling these data with published results in African Americans (n=1,678), ORs were: IFNL4-TT/TT, 3.84 (p=8.6x10(-14)); IFNL4-TT/ΔG, 1.44 (p=0.03); area under the curve was 0.64 for IFNL4-ΔG genotype and 0.61 for rs12979860 ('IL28B'). IFNL4-ΔG is strongly associated with impaired spontaneous HCV clearance.
The Journal of Infectious Diseases 08/2013; · 5.85 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Abstract Several epidemiological studies have suggested that hepatitis C virus (HCV) infection is associated with the presence of obstructive lung disease (OLD). However, there is a strong link between HCV infection and tobacco abuse, a major risk factor for the development of OLD. In this study we analyzed clinical, laboratory and spirometric data from 1068 study participants to assess whether HCV infection, viremia, or HCV-associated end organ damage were associated with OLD. Demographics, risk behavior, serologic status for HCV and HIV, and spirometric measurements were collected from a cross-sectional analysis of the Acquired Immunodeficiency Syndrome (AIDS) Linked to the IntraVenous Experience (ALIVE) study, an observational cohort of IDUs followed in Baltimore, MD since 1988. Of 1,068 participants, 890 (83%) were HCV positive and 174 (16%) met spirometric criteria for OLD. Factors independently associated with OLD were age and BMI. HCV infection, viral load and HCV-associated end organ damage were similar in participants with and without OLD. In summary, there was no independent association between markers of HCV exposure, chronicity, viremia, or HCV-associated end-organ damage with OLD. Our findings support the strong correlation between HCV status, injection drug use, and smoking. These data suggest that HCV may not be a sole contributor to the increased prevalence of OLD described in previous studies of HCV-infected individuals.
[Show abstract][Hide abstract] ABSTRACT: Chronic infection with hepatitis C virus (HCV) is a major global health problem-there are approximately 120-130 million chronic infections worldwide. Since discovery of HCV 24 y ago, there has been a relentless effort to develop successful antiviral therapies. Studies of interferon-α(IFN)-based therapies have helped define treatment parameters, and these treatment strategies have cured a substantial percentage of patients. However, IFN must be injected, and there are problems with tolerability, adherence, and incomplete response in a large percentage of patients. New drug candidates designed to target the virus or the host have recently been introduced at an unprecedented pace. In phase I-III studies, these agents have exceeded expectations and achieved rates of response previously not thought possible. We are therefore entering a new era of therapy for HCV infection and interferon independence.
Clinical gastroenterology and hepatology: the official clinical practice journal of the American Gastroenterological Association 07/2013; · 5.64 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We are entering an important new chapter in the story of hepatitis C virus (HCV) infection. There are clear challenges and opportunities. On the one hand, new HCV infections are still occurring, and an estimated 185 million people are or have previously been infected worldwide. Most HCV-infected persons are unaware of their status yet are at risk for life-threatening diseases such as cirrhosis and hepatocellular carcinoma (HCC), whose incidences are predicted to rise in the coming decade. On the other hand, new HCV infections can be prevented, and those that have already occurred can be detected and treated-viral eradication is even possible. How the story ends will largely be determined by the extent to which these rapidly advancing opportunities overcome the growing challenges and by the vigor of the public health response.
Nature medicine 07/2013; 19(7):850-8. · 28.05 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: Persons with HIV infection have been reported to develop age-related diseases at younger ages than those without HIV. Whether this finding is related to HIV infection or failure to control for other risk factors is unknown. OBJECTIVE: To investigate whether persons with HIV infection develop hepatitis C virus (HCV)-related liver disease at younger ages than similar persons without HIV. DESIGN: Comparison of the severity of liver fibrosis by age among persons who have HCV with and without HIV followed concurrently in the same protocol. SETTING: Observational cohort from Baltimore, Maryland, participating in the ALIVE (AIDS Linked to the IntraVenous Experience) study. PARTICIPANTS: 1176 current and former injection drug users with antibodies to HCV. MEASUREMENTS: Liver fibrosis assessed semiannually from 2006 to 2011 by elastography (FibroScan, Echosens, Paris, France) and using previously validated thresholds for clinically significant fibrosis and cirrhosis; concurrent assessment of medical history, alcohol and illicit drug use, HCV RNA levels, hepatitis B virus surface antigen level, body mass index, and (for those with HIV) CD4+ lymphocyte count and HIV RNA levels. RESULTS: Among 1176 participants with antibodies to HCV, the median age was 49 years and 34% were coinfected with HIV and HCV. Participants contributed 5634 valid liver fibrosis measurements. The prevalence of clinically significant fibrosis without cirrhosis (12.9% vs. 9.5%) and of cirrhosis (19.5% vs. 11.0%) was greater in persons coinfected with HIV and HCV than in those with only HCV (P < 0.001). Increasing age and HIV infection were independently associated with liver fibrosis, as were daily alcohol use, chronic hepatitis B virus infection, body mass index greater than 25 kg/m2, and greater plasma HCV RNA levels. When these factors were kept constant, persons with HIV had liver fibrosis measurements equal to those of persons without HIV, who were, on average, 9.2 years older. LIMITATION: The process of liver fibrosis began before the study in most persons. CONCLUSION: In this cohort, persons who have HCV with HIV have liver fibrosis stages similar to those without HIV who are nearly a decade older. PRIMARY FUNDING SOURCE: National Institute on Drug Abuse.
Annals of internal medicine 02/2013; · 16.10 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Chinese translation
Hepatitis C virus (HCV) infections occur worldwide and either spontaneously resolve or persist and markedly increase the person's lifetime risk for cirrhosis and hepatocellular carcinoma. Although HCV persistence occurs more often in persons of African ancestry and persons with genetic variants near interleukin-28B (IL-28B), the genetic basis is not well-understood.
To evaluate the host genetic basis for spontaneous resolution of HCV infection.
2-stage, genome-wide association study.
13 international multicenter study sites.
919 persons with serum HCV antibodies but no HCV RNA (spontaneous resolution) and 1482 persons with serum HCV antibodies and HCV RNA (persistence).
Frequencies of 792 721 single nucleotide polymorphisms (SNPs).
Differences in allele frequencies between persons with spontaneous resolution and persistence were identified on chromosomes 19q13.13 and 6p21.32. On chromosome 19, allele frequency differences localized near IL-28B and included rs12979860 (overall per-allele OR, 0.45; P = 2.17 × 10-30) and 10 additional SNPs spanning 55 000 base pairs. On chromosome 6, allele frequency differences localized near genes for HLA class II and included rs4273729 (overall per-allele OR, 0.59; P = 1.71 × 10-16) near DQB1*03:01 and an additional 116 SNPs spanning 1 090 000 base pairs. The associations in chromosomes 19 and 6 were independent and additive and explain an estimated 14.9% (95% CI, 8.5% to 22.6%) and 15.8% (CI, 4.4% to 31.0%) of the variation in HCV resolution in persons of European and African ancestry, respectively. Replication of the chromosome 6 SNP, rs4272729, in an additional 745 persons confirmed the findings (P = 0.015).
Epigenetic effects were not studied.
IL-28B and HLA class II are independently associated with spontaneous resolution of HCV infection, and SNPs marking IL-28B and DQB1*03:01 may explain approximately 15% of spontaneous resolution of HCV infection.
Office of AIDS Research, National Institutes of Health, and Frederick National Laboratory for Cancer Research.
Annals of internal medicine 02/2013; 158(4):235-45. · 16.10 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Chronic infection with hepatitis C virus (HCV) is a common cause of liver cirrhosis and cancer. We performed RNA sequencing in primary human hepatocytes activated with synthetic double-stranded RNA to mimic HCV infection. Upstream of IFNL3 (IL28B) on chromosome 19q13.13, we discovered a new transiently induced region that harbors a dinucleotide variant ss469415590 (TT or ΔG), which is in high linkage disequilibrium with rs12979860, a genetic marker strongly associated with HCV clearance. ss469415590[ΔG] is a frameshift variant that creates a novel gene, designated IFNL4, encoding the interferon-λ4 protein (IFNL4), which is moderately similar to IFNL3. Compared to rs12979860, ss469415590 is more strongly associated with HCV clearance in individuals of African ancestry, although it provides comparable information in Europeans and Asians. Transient overexpression of IFNL4 in a hepatoma cell line induced STAT1 and STAT2 phosphorylation and the expression of interferon-stimulated genes. Our findings provide new insights into the genetic regulation of HCV clearance and its clinical management.
[Show abstract][Hide abstract] ABSTRACT: Microbial translocation (MT) is thought to be a major contributor to the pathogenesis of HIV-related immune activation, and circulating lipopolysaccharide (LPS) from gram-negative bacteria is the principle measurement of this process. However, related research has been impeded by inconsistent LPS test results.
Specimens were obtained from HIV-infected adults enrolled in the PEARLS study (ACTG A5175) and HIV-HCV co-infected participants enrolled in a study of liver disease staging using MRI elastography. Pig-tailed macaque specimens were obtained from SIV-infected and -uninfected animals. Samples were tested for LPS using the LAL assay with diazo-coupling modifications to improve sensitive detection.
When exogenous LPS was added to macaque plasma, >25% inhibition of LPS detection was found in 10/10 (100%) samples at 20% plasma concentration compared to control; in contrast 5/10 (50%) samples at 2% plasma concentration (p = 0.07) and 0/10 (0%) at 0.1% plasma concentration (p = 0.004) showed >25% inhibition of LPS detection. Similarly, when LPS was added to human serum, >25% inhibition of LPS detection was found in 5/12 (42%) of samples at 2% serum concentration compared to control, while 0/12 (0%) of samples in 0.1% serum showed >25% inhibition of LPS detection (p = 0.07). Likewise, LPS detection in human sera without exogenous LPS was improved by dilution: LPS was detected in 2/12 (17%) human samples in 2% serum, ranging from 3,436-4,736 pg/mL, compared to 9/12 (75%) samples in 0.1% serum, ranging from 123 pg/mL -60,131 pg/mL (p = 0.016). In a separate validation cohort of HIV-HCV co-infected participants sampled at two different times on the same day, LPS measured in 0.2% plasma and with diazo-coupling was closely correlated between the first and second samples (R = 0.66, p<0.05).
Undiluted serum and plasma mask LPS detection. The extent of MT may be substantially underestimated.
PLoS ONE 08/2012; 7(8):e41258. · 3.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Human immunodeficiency virus (HIV) accelerates hepatitis C virus (HCV) disease progression; however, the effect of liver disease stage and antiviral therapy on the risk of clinical outcomes is incompletely understood.
To determine the incidence of end-stage liver disease (ESLD), hepatocellular carcinoma (HCC), or death according to baseline hepatic fibrosis and antiviral treatment for HIV/HCV coinfected individuals.
Prospective cohort of 638 coinfected adults (80% black, 66% men) receiving care at the Johns Hopkins HIV clinic and receiving a liver biopsy and who were prospectively monitored for clinical events between July 1993 and August 2011 (median follow-up, 5.82 years; interquartile range, 3.42-8.85 years). Histological specimens were scored for hepatic fibrosis stage according to the METAVIR scoring system.
Incidence of composite outcome of ESLD, HCC, or death.
Patients experienced a graded increased risk in incidence of clinical outcomes based on baseline hepatic fibrosis stage (classification range, F0-F4): F0, 23.63 (95% CI, 16.80-33.24); F1, 36.33 (95% CI, 28.03-47.10); F2, 53.40 (95% CI, 33.65-84.76); F3, 56.14 (95% CI, 31.09-101.38); and F4, 79.43 (95% CI, 55.86-112.95) per 1000 person-years (P < .001). In multivariable negative binomial regression, fibrosis stages F2 through F4 and antiretroviral therapy were independently associated with composite ESLD, HCC, or all-cause mortality after adjustment for demographic characteristics, injection drug use, and CD4 cell count. Compared with F0, the incidence rate ratio (RR) for F2 was 2.31 (95% CI, 1.23-4.34; P = .009); F3, 3.18 (95% CI, 1.47-6.88; P = .003); and F4, 3.57 (95% CI, 2.06-6.19; P < .001). Human immunodeficiency virus treatment was associated with fewer clinical events (incidence RR, 0.27; 95% CI, 0.19-0.38; P < .001). For the 226 patients who underwent HCV treatment, the incidence of clinical events did not significantly differ between treatment nonresponders and untreated patients (incidence RR, 1.27; 95% CI, 0.86-1.86; P = .23). In contrast, no events were observed in the 51 patients with sustained virologic response (n = 36) and relapse (n = 15), including 19 with significant fibrosis.
In this cohort of patients with HIV/HCV coinfection, hepatic fibrosis stage was independently associated with a composite outcome of ESLD, HCC, or death.
JAMA The Journal of the American Medical Association 07/2012; 308(4):370-8. · 29.98 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: New trial data and drug regimens that have become available in the last 2 years warrant an update to guidelines for antiretroviral therapy (ART) in human immunodeficiency virus (HIV)-infected adults in resource-rich settings.
To provide current recommendations for the treatment of adult HIV infection with ART and use of laboratory-monitoring tools. Guidelines include when to start therapy and with what drugs, monitoring for response and toxic effects, special considerations in therapy, and managing antiretroviral failure.
Data that had been published or presented in abstract form at scientific conferences in the past 2 years were systematically searched and reviewed by an International Antiviral Society-USA panel. The panel reviewed available evidence and formed recommendations by full panel consensus.
Treatment is recommended for all adults with HIV infection; the strength of the recommendation and the quality of the evidence increase with decreasing CD4 cell count and the presence of certain concurrent conditions. Recommended initial regimens include 2 nucleoside reverse transcriptase inhibitors (tenofovir/emtricitabine or abacavir/lamivudine) plus a nonnucleoside reverse transcriptase inhibitor (efavirenz), a ritonavir-boosted protease inhibitor (atazanavir or darunavir), or an integrase strand transfer inhibitor (raltegravir). Alternatives in each class are recommended for patients with or at risk of certain concurrent conditions. CD4 cell count and HIV-1 RNA level should be monitored, as should engagement in care, ART adherence, HIV drug resistance, and quality-of-care indicators. Reasons for regimen switching include virologic, immunologic, or clinical failure and drug toxicity or intolerance. Confirmed treatment failure should be addressed promptly and multiple factors considered.
New recommendations for HIV patient care include offering ART to all patients regardless of CD4 cell count, changes in therapeutic options, and modifications in the timing and choice of ART in the setting of opportunistic illnesses such as cryptococcal disease and tuberculosis.
JAMA The Journal of the American Medical Association 07/2012; 308(4):387-402. · 29.98 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: INTRODUCTION: Fractures and cirrhosis are major causes of morbidity and mortality among HIV/HCV co-infected persons. It is not known whether vitamin-D deficiency is associated with these outcomes. METHODS: Between 2005 and 2007, 116 HIV/HCV co-infected individuals underwent dual-energy-X-ray-absorptiometry (DXA) within one year of a liver biopsy. 25-hydroxyvitamin D (25OHD) and parathyroid hormone (PTH) were measured from archived samples. Low bone mineral density (BMD) was defined as BMD ≥ 2 standard deviations lower than age-, sex-, and race-matched controls (Z-score ≤ -2.0) at the total hip, femoral neck, or lumbar spine. Histologic fibrosis staging was assessed according to the METAVIR system [0 (no fibrosis) to 4 (cirrhosis)]. RESULTS: The cohort was 87% African-American and 63% men. The median age (interquartile range [IQR]) was 49.9 years (46.5, 53.3). 89% had CD4 count > 200 cells/mm3 and 64% were receiving highly-active-antiretroviral-therapy. The median 25OHD was 19 ng/mL (IQR: 11.0, 26.0). Hypovitaminosis D (25OHD < 15 ng/ml) was present in 41% and secondary hyperparathyroidism, defined by PTH > 65 pg/ml was present in 24%. 27% had low BMD (Z-score < -2) at the spine, femoral neck, or total hip; and 39% had significant hepatic fibrosis (METAVIR ≥ 2). In multivariate analysis, vitamin-D deficiency was not associated with BMD at any site or significant fibrosis. CONCLUSIONS: Vitamin-D deficiency was highly prevalent in this mostly African-American, HIV/HCV co-infected population, but was not related to bone mineral density or liver disease severity. These data suggest that efforts to increase vitamin-D levels in this population may not improve bone or liver outcomes.
[Show abstract][Hide abstract] ABSTRACT: Since 2007, the annual age-adjusted mortality rate in hepatitis C virus (HCV) infection in the United States has been greater than that in HIV disease, reflecting the continuing decline in HIV-related mortality and the continuing increase in HCV-related mortality. The approval of 2 new direct-acting antivirals within the past year, as well as the promise offered by numerous other direct-acting agents in development, provides hope that we will be able to markedly improve our ability to cure HCV disease. The addition of a protease inhibitor (PI) to what has been the standard HCV therapy of peginterferon alfa and ribavirin dramatically improves sustained virologic response rates in treatment-naive patients with genotype 1 infection. Similar results have been observed in some treatment-experienced patients in whom prior peginterferon alfa/ribavirin therapy has failed. The use of these new agents has also permitted response-guided therapy, wherein early sustained virologic response to treatment allows for a shortened treatment duration. However, these new PIs add cost and adverse effects to HCV therapy. Boceprevir is associated with increased risk of anemia and dysgeusia, and telaprevir is associated with increased risk of anemia and skin and gastrointestinal adverse effects. Early studies indicate that the addition of PIs results in high response rates in patients with HCV/HIV coinfection. Other studies suggest that combinations of PIs and other direct-acting antivirals may ultimately permit cure when used in interferon sparing regimens. This article summarizes a presentation by David L. Thomas, MD, MPH, at the IAS-USA live continuing medical education course held in New York City in October 2011.
Topics in antiviral medicine. 04/2012; 20(1):5-10.