Outcome of an outbreak of acute hepatitis C among healthy volunteers participating in pharmacokinetics studies

Simultaneous Hepatitis C Virus Genotyping and Variant Detection in Patients with Thalassemia: A Single-Center Phylogenetic Study

BACKGROUND: Hepatitis C virus (HCV) genotype distribution is different in various regions. A variety of strategies could be used to detect HCV genotypes and subtypes. The aim of the present study was to introduce a genotyping method by an in-house protocol that could be used to determine HCV drug-resistant variants and phylogeny studies. METHODS: Samples from 91 patients with thalassemia were used for HCV genotyping by Cobas 4800 platform, and 50 cases of 1a, 1b, and 3a genotypes underwent amplification and sequencing of NS5A and NS5B by using consensus primers via conventional reverse transcription-polymerase chain reaction (RT-PCR) method. An ABI 3730xl system used for direct sequencing. Raw sequences were analyzed by popular bioinformatics software MEGA6 and CLC workbench 5. Phylogenetic construction was drawn using 1000 replicates bootstrap by the neighbor-joining method. Multiple sequence alignment (MSA) was performed for mutation detection. RESULTS: Sequencing results of 50 HCV isolates subtypes 1a (31/45), 3a (15/22) and 1b (4/8) NS5A and NS5B genes showed there were 72 NS5A and 105 NS5B mutations. Moreover, 8 resistant associated substitutions (RASs) were identified in nine thalassemia cases by multiple sequence alignment (MSA) protein analysis. The phylogenetic tree construct drew confirmed by the Cobas HCV genotyping results. CONCLUSION: The phylogenetic analysis could be a useful tool for HCV genotyping in case of determining the drug-resistant substitutions; however, it is time-consuming and needs expert analysis and interpretation. This preliminary study in Iranian patients with thalassemia introduces specific conventional RT-PCR to find RASs to direct acting antivirals (DAAs) and subtype determination at the same time.

Testing and Clinical Management of Health Care Personnel Potentially Exposed to Hepatitis C Virus - CDC Guidance, United States, 2020

Exposure to hepatitis viruses is a recognized occupational risk for health care personnel (HCP). This report establishes new CDC guidance that includes recommendations for a testing algorithm and clinical management for HCP with potential occupational exposure to hepatitis C virus (HCV). Baseline testing of the source patient and HCP should be performed as soon as possible (preferably within 48 hours) after the exposure. A source patient refers to any person receiving health care services whose blood or other potentially infectious material is the source of the HCP's exposure. Two options are recommended for testing the source patient. The first option is to test the source patient with a nucleic acid test (NAT) for HCV RNA. This option is preferred, particularly if the source patient is known or suspected to have recent behaviors that increase risk for HCV acquisition (e.g., injection drug use within the previous 4 months) or if risk cannot be reliably assessed. The second option is to test the source patient for antibodies to hepatitis C virus (anti-HCV), then if positive, test for HCV RNA. For HCP, baseline testing for anti-HCV with reflex to a NAT for HCV RNA if positive should be conducted as soon as possible (preferably within 48 hours) after the exposure and may be simultaneous with source-patient testing. If follow-up testing is recommended based on the source patient's status (e.g., HCV RNA positive or anti-HCV positive with unavailable HCV RNA or if the HCV infection status is unknown), HCP should be tested with a NAT for HCV RNA at 3-6 weeks postexposure. If HCV RNA is negative at 3-6 weeks postexposure, a final test for anti-HCV at 4-6 months postexposure is recommended. A source patient or HCP found to be positive for HCV RNA should be referred to care. Postexposure prophylaxis of hepatitis C is not recommended for HCP who have occupational exposure to blood and other body fluids. This guidance was developed based on expert opinion (CDC. Updated U.S. Public Health Service guidelines for the management of occupational exposures to HBV, HCV, and HIV and recommendations for postexposure prophylaxis. MMWR Recommend Rep 2001;50[No. RR-11]; Supplementary Figure, https://stacks.cdc.gov/view/cdc/90288) and reflects updated guidance from professional organizations that recommend treatment for acute HCV infection. Health care providers can use this guidance to update their procedures for postexposure testing and clinical management of HCP potentially exposed to hepatitis C virus.

Hepatitis C Virus Postexposure Prophylaxis in the Healthcare Worker: Why Direct-Acting Antivirals Don't Change a Thing

Currently, 380 000-400 000 occupational exposures to blood-borne pathogens occur annually in the United States. The management for occupational HIV or hepatitis B virus exposures includes postexposure prophylaxis (PEP) when necessary; however, PEP is not recommended for hepatitis C virus (HCV) exposures. Recent approval of HCV direct-acting antivirals (DAAs) has renewed discussions as to whether these therapies could be used to prevent infection after exposure. There are no published studies addressing this question, but the prescribing of DAAs for PEP has been reported. We will discuss the differences in transmission of the 3 most common blood-borne pathogens, the natural history of early HCV infection, and the scientific rationale for PEP. In particular, we will discuss how the low feasibility of conducting an adequately powered clinical trial of DAA use for PEP and the low cost-effectiveness of such an intervention is not supportive of targeting limited resources for such use.

Occupational exposures in healthcare workers in University Hospital Dubrava--10 year follow-up study

Occupational hazardous exposure in healthcare workers is any contact with a material that carries the risk of acquiring an infection during their working activities. Among the most frequent viral occupational infections are those transmitted by blood such as hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV). Therefore, they represent a significant public health problem related to the majority of documented cases of professionally acquired infections. Reporting of occupational exposures in University Hospital Dubrava has been implemented in connection with the activity of the Committee for Hospital Infections since January 2002. During the period of occupational exposures' monitoring (from January 2002 to December 2011) 451 cases were reported. The majority of occupational exposures were reported by nurses and medical technicians (55.4%). The most common type of exposure was the needlestick injury (77.6%). 27.9% of the accidents occurred during the blood sampling and 23.5% during the surgical procedure. In 59.4% of the exposed workers aHBs-titer status was assessed as satisfactory. Positive serology with respect to HBV was confirmed in 1.6% of patients, HCV in 2.2% of patients and none for HIV. Cases of professionally acquired infections were not recorded in the registry. Consequences of the occupational exposure could include the development of professional infection, ban or inability to work further in health care services and last but not least a threat to healthcare workers life. It is therefore deemed necessary to prevent occupational exposure to blood-borne infections. The most important preventive action in respect to HBV, HCV and HIV infections is nonspecific pre-exposure prophylaxis.

New tools in HCV diagnosis, in light of the enhanced awareness and the new drugs for treatment: SMARTube and stimmunology

With improved HCV therapy, challenges regarding HCV diagnosis, such as seronegative window period, false positive readings, and differentiation between recent, chronic, and resolved infections, are of increasing importance. To address these challenges an innovative device—SMARTube HIV & HCV—was used. Blood samples were tested for anti-HCV antibodies before and after incubation in the SMARTube, which promotes the in vitro stimulation of in vivo HCV primed lymphocytes, thus enhancing levels of anti-HCV antibodies. Comparing antibody levels, in concordant samples before and after SMARTube, yielded the Stimulation Index (SI). Among 5888 fresh blood samples, from various populations and regions worldwide, 641 were seropositive using plasma, while SMARTube processing (yielding enriched plasma, termed SMARTplasma) enabled diagnosis of 10 additional carriers in high-risk cohorts, that is, earlier detection. Using SMARTplasma eliminated all false positive results, using the current assays. In addition we show that SI calculation may serve as an important tool for differentiating between those who recently seroconverted, carriers of long-term infection, and those who have cleared the virus. SMARTube and the SI could lead to better, more informative diagnosis of HCV infections and play an important role in changing the way we treat both the infected individuals and the epidemic as a whole.

Rapid progression to decompensated cirrhosis, liver transplant, and death in HIV-infected men after primary hepatitis C virus infection

BACKGROUND

We and others have shown that primary hepatitis C (HCV) infection in men infected with human immunodeficiency virus (HIV) causes early-onset liver fibrosis; however, little is known about the long-term natural history of the liver disease in these HIV-infected men.

METHODS

We followed a cohort of HIV-infected men with primary HCV infection in New York City.

RESULTS

Four men who were not cured after their primary HCV infection developed decompensated cirrhosis within 17 months to 6 years after primary HCV infection. Three died within 8 years of primary HCV infection, and 1 survived after liver transplant done 2 years after primary HCV infection. Three of the 4 men had AIDS at the time of primary HCV infection, and the most rapid progression occurred in the 2 men with the lowest CD4 counts at the time of HCV infection. Liver histopathology was most consistent with HCV-induced damage even though some had exposures to other potential hepatotoxins.

CONCLUSIONS

Primary HCV infection resulted in decompensated cirrhosis and death within 2-8 years in 4 HIV-infected men. The rapid onset of fibrosis due to primary HCV infection in HIV-infected men cannot therefore be considered benign. The rate of continued progression to liver failure may be proportional to the degree of underlying immunocompromise caused by HIV infection. More research is needed to better define the mechanisms behind accelerated liver damage.

Case definitions for acute hepatitis C virus infection: a systematic review

BACKGROUND & AIMS

Case definitions for recent hepatitis C virus (HCV) infection vary considerably between studies. The aim of this systematic review was to characterize case definitions for recent HCV and explore the heterogeneity in studies performed to date.

METHODS

A systematic literature search of MEDLINE, SCOPUS, and ISI Web of Knowledge was performed covering all studies of recent HCV infection cited between January 2000 and June 2011. The criteria used by each study to define cases of recent HCV infection were extracted, structured, and analyzed.

RESULTS

Overall, 195 articles were included, with 87% (n=169) providing a clear case definition for recent HCV infection. The most frequently used individual criteria for defining a case included HCV antibody seroconversion (77%), alanine aminotransferase (ALT) elevation (68%), and HCV RNA detection (63%). In studies using HCV antibody seroconversion, the window period between the last negative and the first positive antibody test varied widely across studies (4 weeks to 4 years). Considerable diversity was also observed with respect to the ALT threshold used to characterize ALT elevations, ranging from 2 to 20 times the upper limit of normal. HCV antibody seroconversion was used as a single criterion in 41% of the studies, while all other studies used at least two criteria (range: 2-9). Epidemiology/surveillance studies mostly used a more sensitive case definition, whereas treatment studies, natural history studies, and diagnosis studies used more specific case definitions.

CONCLUSIONS

Marked heterogeneity in case definitions for recent HCV infection was observed. Although a single case definition for recent HCV is not warranted, a degree of standardization within specific study categories would enable improved cross-study comparison and more uniform evaluation of HCV prevention and management strategies.

Phylogeny and phylodinamic of Hepatitis C in Italy

Hepatitis C virus infection (HCV) is one of the most pressing health emergencies in the world with a global prevalence of about 170 million people chronically infected worldwide. In Europe, Italy has the highest HCV prevalence (3 - 4.4%) with peaks of 12.6 - 26% in Southern regions and the major islands. In Italy HCV genotype 1b prevails, and genotype 4 is mainly found in the south of the country where the prevalence is particularly high in regions such as Calabria.

Phylogenetics analysis is a molecular tool widely used to study rapidly-evolving RNA viruses that establish chronic infections such as HCV. Searching the scientific literature, it was found that thirty-nine genetic studies on HCV genotypes have been carried out in Italy between 1997 to 2012 years. However, phylogenetic analysis was performed only in fourteen out of thirty-nine HCV studies (36%) considered. Monitoring the genetic evolution of HCV is an essential step to control the local as well as global HCV epidemic and to develop efficient preventive and therapeutic strategies.

Frequent longitudinal sampling of hepatitis C virus infection in injection drug users reveals intermittently detectable viremia and reinfection

BACKGROUND

Detection of hepatitis C virus (HCV) reinfection and intercalation (ie, intermittent recurrent bouts of viremia with homologous virus interspersed with aviremic periods) requires extensive and frequent evaluation and viral sequencing.

METHODS

HCV infection outcomes were studied prospectively in active injection drug users with recurrent HCV RNA-positive tests after serial negative results. HCV viremia and viral sequences (Core/E1) were assessed from monthly blood samples.

RESULTS

Viral clearance, reinfection, and intercalating infection were all detected. Among 44 participants with apparently resolved HCV (26 incident HCV clearers and 18 enrolled with already resolved infection), 36 (82%) remained persistently HCV RNA negative, but 8 demonstrated intermittent recurrent viremia. Four of these (50%) had confirmed reinfection with a heterologous virus; 3 demonstrated viral intercalation, and 1 was not classifiable as either. Estimated incidence of first reinfection was 5.4 per 100 person-years (95% confidence interval, 2.0-14.5). Six (75%) participants, including 3 of 4 with reinfection, demonstrated sustained viral clearance for a median of 26 months since last HCV RNA test.

CONCLUSIONS

These results show that frequent monitoring and viral sequencing are required to correctly assess HCV outcomes and estimate incidence of reinfection (which was previously overestimated). Sustained clearance may take many months and occur after episodes of reinfection and viral intercalation. Three of 4 subjects who had confirmed reinfection showed evidence of long-term clearance. Viral intercalation occurs with significant frequency. Further studies of these events, especially immunological, are needed to inform HCV clinical care and vaccine development.

Clinical evaluation of the signal-to-cutoff ratios of hepatitis C virus antibody screening tests used in China

The clinical diagnosis of hepatitis C virus (HCV) infection is important to direct an accurate course of therapy. Previous studies have reported a correlation between the signal-to-cutoff (S/CO) ratios of the anti-HCV screening test and confirm HCV infections for American anti-HCV screening kits as well as for those in China. It is currently unknown whether clinical laboratories use the same threshold S/CO ratios under routine conditions and if these values are acceptable for the analysis of Chinese samples. A total of 336 anti-HCV screening-test-positive serum samples were tested in duplicate using different lots of three most commonly used enzyme immunoassay (EIA) kits available in China. Samples were also tested using the Architect Anti-HCV chemiluminescent microparticle immunoassay (CMIA) kit and measured for HCV RNA. Recombinant immunoblot assays (RIBA) were additionally performed on samples with HCV RNA-negative results with RIBA HCV 3.0. The relationship between S/CO ratios and confirmed HCV infection rates were analyzed. The threshold S/CO ratio for each screening kit correlated with the ≥ 95% positive predictive value was InTec 12.0, KHB 4.0, Wantai 5.0, and Abbott Architect 5.0. Therefore, the same threshold S/CO ratios for manufactured domestically EIA kits was difficult to attain. A multi-center study with a large sample size is required to identify a uniform threshold S/CO ratio for use in different diagnostic laboratories. Alternatively, individual laboratories may be required to establish threshold S/CO ratios in their own laboratories to obtain consistent diagnostic results.

Female sex and IL28B, a synergism for spontaneous viral clearance in hepatitis C virus (HCV) seroconverters from a community-based cohort

BACKGROUND & AIMS

Since acute hepatitis C virus (HCV) infection is often asymptomatic, it is difficult to examine the rate and determinants of spontaneous clearance. Consequently, these studies are subject to bias, which can potentially lead to biased rates of viral clearance and risk estimates. We evaluated determinants of spontaneous HCV clearance among HCV seroconverters identified in a unique community-based cohort.

METHODS

Subjects were 106 drug users with documented dates of HCV seroconversion from the Amsterdam Cohort Study. Logistic regression was used to examine sociodemographic, behavioral, clinical, viral and host determinants, measured around acute infection, of HCV clearance.

RESULTS

The spontaneous viral clearance rate was 33.0% (95% confidence interval (CI) 24.2-42.8). In univariate analyses female sex and fever were significantly associated with spontaneous clearance. The favorable genotypes for rs12979860 (CC) and rs8099917 (TT) were associated with spontaneous clearance, although borderline significant. In multivariate analysis, females with the favorable genotype for rs12979860 (CC) had an increased odds to spontaneously clear HCV infection (adjusted OR 6.62, 95% 2.69-26.13), whereas females with the unfavorable genotype were as likely as men with the favorable and unfavorable genotype to clear HCV. Chronic Hepatitis B infection and absence of HIV coinfection around HCV seroconversion also favor HCV clearance.

CONCLUSIONS

This study shows that co-infection with HIV and HBV and genetic variation in the IL28B region play an important role in spontaneous clearance of HCV. Our findings suggest a possible synergistic interaction between female sex and IL28B in spontaneous clearance of HCV.

NS4A protein as a marker of HCV history suggests that different HCV genotypes originally evolved from genotype 1b

BACKGROUND

The 9.6 kb long RNA genome of Hepatitis C virus (HCV) is under the control of RNA dependent RNA polymerase, an error-prone enzyme, for its transcription and replication. A high rate of mutation has been found to be associated with RNA viruses like HCV. Based on genetic variability, HCV has been classified into 6 different major genotypes and 11 different subtypes. However this classification system does not provide significant information about the origin of the virus, primarily due to high mutation rate at nucleotide level. HCV genome codes for a single polyprotein of about 3011 amino acids which is processed into structural and non-structural proteins inside host cell by viral and cellular proteases.

RESULTS

We have identified a conserved NS4A protein sequence for HCV genotype 3a reported from four different continents of the world i.e. Europe, America, Australia and Asia. We investigated 346 sequences and compared amino acid composition of NS4A protein of different HCV genotypes through Multiple Sequence Alignment and observed amino acid substitutions C22, V29, V30, V38, Q46 and Q47 in NS4A protein of genotype 1b. Furthermore, we observed C22 and V30 as more consistent members of NS4A protein of genotype 1a. Similarly Q46 and Q47 in genotype 5, V29, V30, Q46 and Q47 in genotype 4, C22, Q46 and Q47 in genotype 6, C22, V38, Q46 and Q47 in genotype 3 and C22 in genotype 2 as more consistent members of NS4A protein of these genotypes. So the different amino acids that were introduced as substitutions in NS4A protein of genotype 1 subtype 1b have been retained as consistent members of the NS4A protein of other known genotypes.

CONCLUSION

These observations indicate that NS4A protein of different HCV genotypes originally evolved from NS4A protein of genotype 1 subtype 1b, which in turn indicate that HCV genotype 1 subtype 1b established itself earlier in human population and all other known genotypes evolved later as a result of mutations in HCV genotype 1b. These results were further confirmed through phylogenetic analysis by constructing phylogenetic tree using NS4A protein as a phylogenetic marker.

[Current status of acute hepatitis C]

Acute hepatitis C (AHC) is an increasing health issue. Despite the decline of blood-to-blood transmission of hepatitis C virus (HCV) through donor screening programs and a decline in intravenous drug use, the incidence of sexual transmission has now increased, particularly in HIV-infected homosexual patients. The presentation is almost always asymptomatic, which complicates diagnosis. Spontaneous clearance of the virus occurs in 25% of cases and usually, within the first three months after onset of symptoms and in symptomatic patients. If serum HCV-RNA remains detectable after this period, antiviral treatment should be started without delay, since sustained viral response rate in the acute phase is higher than that achieved with chronic liver disease. The optimal treatment regimen (interferon alone or combined with ribavirin) and its duration are not clearly established at the present time.

Adaptive immunity to the hepatitis C virus

The hepatitis C virus (HCV) is a global public health problem affecting approximately 2% of the human population. The majority of HCV infections (more than 70%) result in life-long persistence of the virus that substantially increases the risk of serious liver diseases, including cirrhosis and hepatocellular carcinoma. The remainder (less than 30%) resolves spontaneously, often resulting in long-lived protection from persistence upon reexposure to the virus. To persist, the virus must replicate and this requires effective evasion of adaptive immune responses. In this review, the role of humoral and cellular immunity in preventing HCV persistence, and the mechanisms used by the virus to subvert protective host responses, are considered.

An overview about hepatitis C: a devastating virus

Hepatitis C (HCV) is the disease that has affected around 200 million people globally. HCV is a life threatening human pathogen, not only because of its high prevalence and worldwide burden but also because of the potentially serious complications of persistent HCV infection. Chronicity of the disease leads to cirrhosis, hepatocellular carcinoma and end-stage liver disease. HCV positive hepatocytes vary between less than 5% and up to 100%, indicating the high rate of replication of viral RNA. HCV has a very high mutational rate that enables it to escape the immune system. Viral diversity has two levels; the genotypes and Quasiaspecies. Major HCV genotypes constitute genotype 1, 2, 3, 4, 5 and 6 while more than 50 subtypes are known. All HCV genotypes have their particular patterns of geographical distribution and a slight drift in viral population has been observed in some parts of the globe.

Outcome of a hepatitis C outbreak among patients in a pain management clinic

BACKGROUND AND AIMS

The aims of this study are to evaluate the natural history and response to therapy of patients following a hepatitis C outbreak in a pain management clinic.

METHODS

A retrospective cohort study was conducted on patients who acquired hepatitis C virus (HCV) at a pain management clinic. Medical records were retrospectively reviewed for 77% of patients with hepatitis C included in the outbreak to obtain data regarding laboratory results, treatment, and outcomes. Chi-square, Fisher's exact, and Student's t-test were used to determine variables that were significantly associated with spontaneous clearance or sustained virologic response to therapy.

RESULTS

Fifty Caucasian patients (31 women, 19 men; mean age 52 years) were included. Eleven of 50 (22%) patients cleared HCV spontaneously (clearers). The mean age of clearers was 47 years as compared with 57 years for nonclearers (P = 0.04). Liver biopsies were obtained by treating gastroenterologists in 31 patients with mean grade and stage of 2.1 and 1.7, respectively. Gastroenterologists treated 31 of 39 patients with pegylated interferon and ribavirin after a median of 354 (range 140-1,099) days post exposure. Sustained viral response (SVR) was observed in 65% (20/31) on an intention-to-treat basis. In patients who completed therapy, 91% (20/22) achieved SVR. Age, sex, weight, pretreatment alanine aminotransferase (ALT), and histologic parameters were not associated with SVR.

CONCLUSIONS

In this large cohort of US immunocompetent patients with recent HCV infection, 22% resolved spontaneously. Younger age was the only predictor of spontaneous clearance. In patients with early chronic HCV, 65% achieved SVR.

A case-control study of factors associated with resolution of hepatitis C viremia in former blood donors (CME)

BACKGROUND

Nucleic acid testing (NAT) is performed on blood collected in the United States allowing for the classification of hepatitis C virus (HCV) antibody-positive donors into resolved and chronic hepatitis C infections. We report a case-control study of factors associated with HCV resolution.

STUDY DESIGN AND METHODS

Blood donors with resolved (HCV antibody positive, RNA negative defined as "cases") or chronic (HCV antibody positive, RNA positive defined as "controls") based on their index donation HCV test results were enrolled. Participants completed a risk factor, symptoms, and treatment questionnaire followed by HCV antibody, HCV RNA, and liver biochemical testing.

RESULTS

We enrolled 100 cases and 202 controls. In a multivariate logistic regression model, significant independent effects for spontaneous viral clearance were observed for African American (inverse; odds ratio [OR], 0.11; 95% confidence interval [CI], 0.01-0.87), autologous blood donation (OR, 4.70; 95% CI, 2.02-10.94), alcohol intake (OR, 2.39; 95% CI, 1.13-5.03), and transfusion before May 1990 (inverse; OR, 0.36; 95% CI, 0.14-0.91). Cases admitting injection drug use had shorter time since first injection than did controls. Forty-nine index RNA positive controls received antiviral therapy and 25 (51%) were RNA negative at enrollment; surprisingly several RNA-negative cases received liver biopsies and/or antiviral treatment.

CONCLUSIONS

We document the role donor screening plays in the identification, subsequent medical evaluation, and treatment among individuals who presumably did not know that they were at risk for HCV infection. Additionally, we confirmed race/ethnicity as a determinant of clearance and suggest infectious dose and route of infection may play a role in clearance.

Early treatment improves outcomes in acute hepatitis C virus infection: a meta-analysis

Acute hepatitis C virus infection is associated with high rates of spontaneous clearance and variable rates of treatment-induced clearance. The benefit of early treatment versus awaiting spontaneous clearance is unknown, as is the optimal timing of treatment.We performed a MEDLINE and EMBASE search for the time period 1950 to October 2008. All English language abstracts using the search terms acute hepatitis C, hepatitis C and acute and hepatitis C and acute disease or acute infection were reviewed. Bibliographies were reviewed.Twenty-two studies including 1075 patients met the inclusion criteria. The sustained virologic response (SVR) rate for treated patients was 78%, significantly higher than 55.1% in untreated patients (OR = 3.08, 95% CI: 1.8-4.8 P value <0.0001). Mean time from diagnosis to spontaneous clearance was 9.7 weeks (SD 6.5). SVR rates varied inversely with time from acute HCV diagnosis. SVR rates for treatment within 12 weeks was 82.5% (95% CI: 75.6-89.3), significantly better than the clearance rates in untreated patients (P < 0.001). Response rates fell to 66.9% for treatment between 12 and 24 weeks, and decreased further to 62.5% for treatment beyond 24 weeks. Rates of viral clearance in treated patients with acute hepatitis C virus infection were significantly higher than that in untreated patients. Treatment rates were highest when treatment was initiated within 12 weeks of diagnosis. Based on these findings, we would advocate a 12 week period of observation for spontaneous clearance before treatment initiation. If no clearance has occurred by 12 weeks, treatment should be initiated.

Acute hepatitis C virus infection in young adult injection drug users: a prospective study of incident infection, resolution, and reinfection

BACKGROUND

Hepatitis C virus (HCV) infection, clearance, and reinfection are best studied in injection drug users (IDUs), who have the highest incidence of HCV and are likely to represent most infections.

METHODS

A prospective cohort of HCV-negative young IDUs was followed up from January 2000 to September 2007, to identify acute and incident HCV and prospectively study infection outcomes.

RESULTS

Among 1,191 young IDUs screened, 731 (61.4%) were HCV negative, and 520 (71.1%) of the 731 were enrolled into follow-up. Cumulative HCV incidence was 26.7/100 person-years of observation (95% confidence interval [CI], 21.5-31.6). Of 135 acute/incident HCV infections, 95 (70.4%) were followed; 20 (21.1%) of the 95 infections cleared. Women had a significantly higher incidence of viral clearance than did men (age-adjusted hazard ratio, 2.91 [95% CI, 1.68-5.03]) and also showed a faster rate of early HCV viremia decline (P < .01). The estimated reinfection rate was 24.6/100 person-years of observation (95% CI, 11.7-51.6). Among 7 individuals, multiple episodes of HCV reinfection and reclearance were observed.

CONCLUSIONS

In this large sample of young IDUs, females show demonstrative differences in their rates of viral clearance and kinetics of early viral decline. Recurring reinfection and reclearance suggest possible protection against persistent infection. These results should inform HCV clinical care and vaccine development.

Healthcare-associated hepatitis C virus transmission among patients in an abdominal organ transplant center

BACKGROUND

De novo hepatitis C virus (HCV) infection among transplant patients is rarely recognized but can have severe consequences. We investigated the scope, source, and mode of HCV transmission within a transplant center after incident HCV infection was identified in 2 patients who had liver transplantation in late 2006.

METHODS

Patients were interviewed, and transplant logs, medical records, and staff practices were reviewed to identify opportunities for HCV transmission. Infection via receipt of blood or organs was evaluated. Molecular epidemiology was used to determine the relatedness between persons with incident and chronic HCV infection.

RESULTS

HCV from infected blood or organ donors was ruled out. Among the 308 patients who underwent transplant in 2006, no additional incident HCV infections were identified. Eighty-five (28%) had pre-transplant chronic HCV infection; 13 were considered possible HCV source patients based upon shared days on the inpatient unit, nursing assignment, or invasive procedures in common with incident HCV case-patients. Viral isolates from 1 HCV source patient and 1 incident case-patient were found to be highly related by quasispecies analysis, confirming patient-to-patient HCV transmission. Possible modes of transmission identified were the improper use of multidose vials, sharing of blood-contaminated glucometers, and touch contamination.

CONCLUSION

Sporadic transmission or endemic levels of HCV transmission might be overlooked in a setting with high HCV prevalence, such as liver transplant units, where multiple, repeated opportunities for patient-to-patient HCV transmission can occur. Surveillance through pre- and post-transplant screening is necessary to identify incident HCV infection in this setting. Constant, meticulous attention must be paid to maintaining aseptic technique and good infection control practices to eliminate HCV transmission opportunities.

The hepatitis C virus enigma

Hepatitis C virus (HCV) has a high propensity to establish chronic infection with end-stage liver disease. The high turnover of virus particles and high transcription error rates due to lack of proof-reading function of the viral polymerase imply that HCV exists as quasispecies, thus enabling the virus to evade the host immune response. Clearance of the virus is characterized by a multispecific, vigorous and persistent T-cell response, whereas T-cell responses are weak, narrow and transient in patients who develop chronic infection. At present, standard treatment is a combination of pegylated interferon-alpha and ribavirin, with a sustained viral response rate of 40-80%, depending on genotype. The mechanisms for the observed synergistic effects of the two drugs are still not known in detail, but in addition to direct antiviral mechanisms, the immunomodulatory effects of both drugs seem to be important, with a shift from Th2- to Th1-cytokine profiles in successfully treated patients. This article describes virus-host relations in the natural course of HCV infection and during treatment.

Liver fibrosis during an outbreak of acute hepatitis C virus infection in HIV-infected men: a prospective cohort study

Outbreaks of acute hepatitis C virus (HCV) infection are occurring in HIV-infected men who have sex with men. We evaluated risk factors and liver histopathology in 11 consecutively enrolled men with newly acquired HCV infection that was diagnosed on the basis of antibody seroconversion, new elevations in alanine aminotransferase level, and wide fluctuations in HCV RNA level. Ten patients reported unprotected anal intercourse, and 7 reported "club-drug" use, including methamphetamine. Liver biopsy showed moderately advanced fibrosis (Scheuer stage 2) in 9 patients (82%). No cause of liver damage other than acute HCV infection was identified. The specific pathways leading to periportal fibrosis in HIV-infected men with newly acquired HCV infection require investigation.

Epidemiological characteristics and medical follow-up of 61 patients with acute hepatitis C identified through the hepatitis C surveillance system in France

This study aimed to describe current epidemiological and clinical characteristics, medical follow-up and outcome in the real practice of acute hepatitis C (AHC) patients. AHC cases were retrospectively identified through the French Hepatology Reference Centres Surveillance system and additional data were collected. Sixty-one patients with AHC were identified (sex ratio: M/F 1.7/1; mean age 39 years). Forty-four (72%) had documented seroconversion within a 6-month period. Main reported risk exposures were intravenous or nasal drug use (35%), invasive medical procedures (25%) and sexual contact with a HCV-positive partner (20%). Spontaneous clearance of HCV RNA was observed in seven out of 16 patients followed without therapy. This study confirms the major role of drug use in HCV transmission and highlights the role of invasive medical procedures and occupational exposure.

Hepatitis infection in the treatment of opioid dependence and abuse

Many new and existing cases of viral hepatitis infections are related to injection drug use. Transmission of these infections can result directly from the use of injection equipment that is contaminated with blood containing the hepatitis B or C virus or through sexual contact with an infected individual. In the latter case, drug use can indirectly contribute to hepatitis transmission through the dis-inhibited at-risk behavior, that is, unprotected sex with an infected partner. Individuals who inject drugs are at-risk for infection from different hepatitis viruses, hepatitis A, B, or C. Those with chronic hepatitis B virus infection also face additional risk should they become co-infected with hepatitis D virus. Protection from the transmission of hepatitis viruses A and B is best achieved by vaccination. For those with a history of or who currently inject drugs, the medical management of viral hepatitis infection comprising screening, testing, counseling and providing care and treatment is evolving. Components of the medical management of hepatitis infection, for persons considering, initiating, or receiving pharmacologic therapy for opioid addiction include: testing for hepatitis B and C infections; education and counseling regarding at-risk behavior and hepatitis transmission, acute and chronic hepatitis infection, liver disease and its care and treatment; vaccination against hepatitis A and B infection; and integrative primary care as part of the comprehensive treatment approach for recovery from opioid abuse and dependence. In addition, participation in a peer support group as part of integrated medical care enhances treatment outcomes. Liver disease is highly prevalent in patient populations seeking recovery from opioid addiction or who are currently receiving pharmacotherapy for opioid addiction. Pharmacotherapy for opioid addiction is not a contraindication to evaluation, care, or treatment of liver disease due to hepatitis virus infection. Successful pharmacotherapy for opioid addiction stabilizes patients and improves patient compliance to care and treatment regimens as well as promotes good patient outcomes. Implementation and integration of effective hepatitis prevention programs, care programs, and treatment regimens in concert with the pharmacological therapy of opioid addiction can reduce the public health burdens of hepatitis and injection drug use.

The course of hepatitis C viraemia in transfusion recipients prior to availability of antiviral therapy

Knowing the likely distribution of intervals from hepatitis C infection to first RNA-negativity is important in deciding about therapeutic intervention. Prospectively collected sera and data from the Transfusion-transmitted Viruses Study (1974-1980) provide specific dates of infection and pattern of alanine aminotransferase (ALT) elevations. We examined frequency, timing and correlates of spontaneous resolution for 94 acutely infected transfusion recipients followed for a median of 9.5 months. Later, follow-up sera (>10 years) were available for 27 of the 94 cases from a Veterans Administration (VA) Study (1989-1990). Twenty-five (27%) of the 94 cases were classified as probably resolved during the episode itself. First RNA negativity occurred at 6-50 weeks (median, 19.5 weeks) after infection, and 5-43 weeks (median, 11 weeks) after ALT elevation. Thirteen of the 25 cases remained RNA-negative subsequently; 12 others had 1-6 RNA-positive sera intercalated between first and last RNA-negative results. RNA negativity, therefore, began variably and was interrupted in 12 cases of 25 (48%) by transient RNA-positive sera. Five of these 25 patients who were RNA-negative in the last study specimen had late, Veterans Administration Study follow-up; none showed viraemia. Of the remaining 69 transfusion transmitted virus study recipients, whose last serum was RNA-positive, two cleared viraemia after the last study serum but before late follow-up. Eleven (16%) had 23 intercalated RNA-negative sera before last positivity. RNA status, therefore, needs monitoring for many months before judging the spontaneous outcome as transient negativity may occur. Resolution was significantly more common in women and symptomatic cases; it was not associated with viral load in the infectious donation, HCV genotype, or the recipient's age.

Spontaneous clearance of childhood hepatitis C virus infection

To describe the spontaneous clearance rate of childhood hepatitis C virus (HCV) infection, to determine whether route of transmission affects the clearance rate and to identify other predictors of clearance. Children with chronic hepatitis C were identified between 1990 and 2001. The rate of spontaneous clearance (defined as >or=2 positive anti-HCV antibody test but negative HCV RNA) was calculated using survival analysis. Univariate and multivariate predictor variables [route of transmission, age at infection, age at last follow-up, alanine aminotransferase (ALT) and gender] for clearance were evaluated. Of 157 patients, 28% of children cleared infection (34 transfusional and 10 nontransfusional cases). The 123 transfusional cases were older at time of infection and at follow-up, compared with the 34 nontransfusional cases. Younger age at follow-up (p < 0.0001) and normal ALT levels (p < 0.0001) favoured clearance. Among cases of neonatal infection, 25% demonstrated spontaneous clearance by 7.3 years. The rate of spontaneous clearance of childhood HCV infection was comparable between transfusional and nontransfusional cases. If clearance occurs, it tends to occur early in infection, at a younger age.

Distinguishing acute from chronic and resolved hepatitis C virus (HCV) infections by measurement of anti-HCV immunoglobulin G avidity index

An assay to measure avidity index (AI) was developed to diagnose incident hepatitis C virus (HCV) infections. The assay demonstrated an AI value statistically significantly lower in primary HCV infections than in chronic infections. When the assay was applied to past resolved infections, the difference in AI values was not as significant as the difference between incident and chronic infections. Lower AI values obtained in past resolved infections may be directly related to lower levels of immunoglobulin G anti-HCV in past resolved infections than in either new infections or chronic infections.

Clinical course and outcome of a nosocomial outbreak of hepatitis C in a urology ward

This paper describes a prospective study of the clinical course and outcome of a nosocomial outbreak of hepatitis C virus (HCV) infection in six male urology patients at a hospital in Stara Zagora, Bulgaria. These patients had been previously hospitalised in the urology ward, during which all had received intravenous therapy. Approximately three weeks later, all six were admitted to the infectious diseases unit with acute hepatitis, shown to be caused by HCV genotype 1b. The diagnosis was confirmed by polymerase chain reaction during the first week of their hospital stay. Infected patients were followed up for 30 months following diagnosis and 54 potential contacts for 6 months post-exposure. Four patients recovered completely; one developed chronic HCV infection and one died. The latter already had cirrhosis due to co-infection with hepatitis B virus. The investigation established the index case as a patient with chronic hepatitis C, who had been an in-patient on the same ward at the same time. The most likely route of transmission was intravenous heparin flushes administered with a common syringe. Contrary to the common assumption that acute HCV infection often leads to chronic disease, only one chronic case was observed during the 30-month period of investigation.

Acute hepatitis C in Israel: a predominantly iatrogenic disease?

BACKGROUND AND AIMS

Acute hepatitis C virus infection in the era of universal screening of blood products has not disappeared, and is thought to be transmitted primarily via injecting drug use. A growing body of evidence supports iatrogenic transmission as an important mode of transmission. The aim of this study was to examine transmission routes and clinical characteristics in a group of patients with acute hepatitis C in Israel.

METHODS

A retrospective chart review was conducted in three different liver clinics in Israel, of all new hepatitis C patients. Patients identified as possible acute hepatitis C were re-interviewed and all other sources such as blood bank records and pre-employment check-ups reviewed in order to establish the diagnosis of acute hepatitis C infection and to identify the transmission route.

RESULTS

Twenty-nine patients were found to have acute hepatitis C, representing 0.75% of all new referrals for hepatitis C. The most frequent (65%) mode of transmission was iatrogenic involving several, often minimal, procedures and clinical settings. The group in which iatrogenic transmission was suspected was older and the patients more often in monogamous relationship compared with other transmission routes groups. Injecting drug use was the second most common route of infection. Spontaneous seroconversion has occurred in approximately one third of the patients.

CONCLUSIONS

Acute hepatitis C in the post universal blood products screening era was found to be predominantly an iatrogenic disease in the investigated localities. This finding should direct attention and resources towards the development and implementation of preventive measures.

Outcomes and treatment of acute hepatitis C virus infection in a United States population

BACKGROUND & AIMS

Acute hepatitis C infection progresses to chronic infection in up to 80% of infected persons. Reports from Europe indicate that early treatment of acute hepatitis C infection produces sustained virologic response rates as high as 80%-98%. However, the outcome of acute hepatitis C infection in United States cohorts is not well-characterized.

METHODS

We describe the clinical course of 28 episodes of acute hepatitis C infection in 24 persons at our institution.

RESULTS

Of the 28 infections, 7 episodes resolved spontaneously. Of the remaining 21 episodes, 16 were treated, and 5 did not receive treatment. Of the 16 treated episodes, 4 received interferon and ribavirin, 11 received pegylated interferon and ribavirin, and 1 was treated initially with interferon monotherapy followed by pegylated interferon monotherapy. Among those episodes treated with interferon, 3 of 4 experienced sustained virologic response. Among those episodes treated with pegylated interferon, all 12 achieved SVR. In total, 15 of 16 treated patients (94%) experienced SVR. In all, 18 of the 24 patients (75%) experienced spontaneous or treatment-induced sustained virologic clearance.

CONCLUSIONS

Our experience with treated and untreated acute HCV infection is comparable to that observed in Europe. Patients treated with antiviral therapy had an excellent response. Randomized trials to investigate immediate versus delayed treatment of acute hepatitis C infection are warranted. In view of these strongly positive outcomes, increased vigilance for acute hepatitis C becomes essential.

Sustained viral response of a case of acute hepatitis C virus infection via needle-stick injury

A 29-year-old nurse with a hepatitis C virus (HCV) infection caused by needle-stick injury was treated with interferon-beta starting about one year after the onset of acute hepatitis. The patient developed acute hepatitis C with symptoms of general fatigues, jaundice, and ascites 4 wk after the needle-stick injury. When these symptoms were presented, the patient was pregnant by artificial insemination. She hoped to continue her pregnancy. After delivery, biochemical liver enzyme returned to normal levels. Nevertheless, HCV RNA was positive and the pathological finding indicated a progression to chronicity. The genotype was 1b with low viral load. Daily intravenous injection of interferon-beta at the dosage of six million units was started and continued for eight weeks. HCV was eradicated without severe adverse effects. In acute hepatitis C, delaying therapy is considered to reduce the efficacy but interferon-beta therapy is one of the useful treatments for hepatitis C infection in chronic phase.

Potential biases in estimates of hepatitis C RNA clearance in newly acquired hepatitis C infection among a cohort of injecting drug users

Estimates of hepatitis C virus (HCV) clearance following acute infection range from 14 to 46%. This wide range is likely to be due to the characteristics of the populations studied and analysis methods. This paper examines how differing definitions of clearance parameters affect estimates of viral clearance in a cohort of 85 injecting drug users with newly acquired HCV infection. Kaplan-Meier estimates of time to HCV clearance were determined using varying definitions of eligible cohort, viral clearance, date of infection and date of clearance. Based on which combinations of definitions were used, the number of subjects eligible for analysis ranged from 27 to 75, clearance rate ranged from 14 to 68% and time to achieving 25% clearance ranged from approximately 5 months to 14 months. Standardized definitions and methodologies are required to enable valid comparisons of rates of clearance across newly acquired HCV infection natural history studies.

Prospective study of viral clearance and CD4(+) T-cell response in acute hepatitis C primary infection and reinfection

BACKGROUND

The outcome of acute hepatitis C is determined by early host-virus interactions, particularly involving the antiviral T-cell response.

OBJECTIVES

To identify early prognostic markers of spontaneous resolution of acute hepatitis C by performing a comprehensive analysis of viral and immunological factors during the natural course of acute HCV infection and reinfection.

STUDY DESIGN

20 patients were investigated prospectively during acute HC or confirmed reinfection and 18 of them during follow up after spontaneous or treatment-induced elimination of the virus and resolution of the disease. Multiparameter flow cytometry was used to functionally characterize virus-specific CD4(+) T-cell responses relative to the virologic outcome.

RESULTS

Parallel immunologic and virologic monitoring of patients with acute HC identified distinct patterns of host-virus interaction related to HCV persistence or clearance. The highest frequency of antiviral Th1 cytokine-producing CD4(+) T-cells was observed in patients with HCV reinfection, preceding rapid viral clearance within 3 weeks after disease onset. In all patients who subsequently cleared viremia, CD4(+) T-cells produced Th1 cytokines following stimulation with non-structural HCV antigens (NS3 and NS4). In contrast, a chronic course of disease was associated with the absence of antiviral Th1 cytokine producing cells from the first weeks after onset of disease (acute persistent HC), or with fluctuating RNA levels (yo-yo pattern) and gradual waning of antiviral Th1 cells.

CONCLUSIONS

The results highlight the variability of immune response pattern in acute hepatitis C. Most importantly, "acute persistent hepatitis C" and a lack of TH1 effector cells within the first months of acute hepatitis C represent efficacious predictors of viral persistence and could thus be used as criteria in selecting candidates for early antiviral treatment.

Different outcomes of nosocomial infection with hepatitis C virus from the same origin

The outcome of infection with hepatitis C virus (HCV) varies substantially from self-limiting infection to chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma among the individuals. The mechanisms that determine the clearance or the persistence of HCV have not yet been clarified. Here, we experienced two cases of hospital-related infection with HCV from the same origin but with quite different outcomes. One case resolved after an episode of acute hepatitis, while the other case developed a chronic hepatitis although they were infected with HCV of the same origin. Although infected with the virus of the same origin, the clinical and virological courses were completely different. This suggests that host factors play a major role in conditioning the outcome of acute HCV infection.

Spontaneous viral clearance following acute hepatitis C infection: a systematic review of longitudinal studies

A large number of studies have reported on spontaneous viral clearance rates in acute hepatitis C infection, however most have been small, and reported rates have varied quite widely. To improve the precision of the estimated rate of spontaneous viral clearance, a systematic review was conducted of longitudinal studies. Factors associated with viral clearance were also examined. Inclusion criteria for studies were: longitudinal assessment from time of acute hepatitis C; hepatitis C virus RNA analysis as determinant of viral clearance; untreated for acute hepatitis C. Information on study population, and factors that may influence viral clearance were extracted from each study. Viral clearance was defined among individuals with at least 6 months follow-up following acute hepatitis C. The number of subjects with viral clearance was expressed as a proportion for each study and a weighted mean for proportion was calculated. A total of 31 studies were examined. Study populations included nine studies of post-transfusion hepatitis, 19 of acute clinical hepatitis, and three of sero-incident cases. In total, data was available for 675 subjects and the mean study population was 22 (range 4-67). The proportion with viral clearance ranged from 0.0 to 0.8, with a weighted mean of 0.26 (95% CI 0.22-0.29). Factors associated with viral clearance were female gender and acute clinical hepatitis C study population. Further studies are required to more clearly define predictors of clearance and guide therapeutic intervention strategies.

Surveillance of acute hepatitis C in Cairo, Egypt

Surveillance of acute hepatitis has been set up in two fever hospitals in Cairo to diagnose acute hepatitis C. Patients were categorized as definite acute hepatitis C with positive hepatitis C virus (HCV) RNA and without anti-HCV antibody, or probable acute hepatitis C with positive HCV RNA, positive anti-HCV antibody, alanine aminotransferase >/=4 times the upper limit of normal (ULN), and high risk parenteral exposure in the 1--3 months prior to the beginning of symptoms. From May to November 2002, 315 patients were recruited in the study. Of these, 115 (36.5%) had acute hepatitis A, 89 (28.3%) had acute hepatitis B, and 111 (35.2%) had non-A non-B acute hepatitis. Of the total with complete data (n=309), 12 (3.9%, 95% CI=2.0%-6.7%) had definite acute hepatitis C, and 11 (3.6%, 95% CI=1.8%-6.3%) had probable acute hepatitis C. In patients with definite acute hepatitis C, dental exposure (n=5) and intravenous drug use (n=2), were the only high risk procedures found in the 6 months prior to diagnosis. Five patients had no identifiable parenteral exposure. In conclusion, results from this study suggest that acute hepatitis C can be diagnosed by surveillance of acute hepatitis in hospital settings in Cairo and that minor community exposures contribute substantially to local HCV transmission.

Challenges and Controversies in the Management of Hepatitis C Virus Infection (Part 1)

Hepatitis C virus (HCV) is emerging as a public health issue in most counties worldwide. The prevalence of HCV infection varies among different geographical areas from 0.5% to 40% with an overall global prevalence of 3%. The WHO estimates that around 170 million people are chronically infected with HCV world wide. Hepatitis CV infection causes a slowly progressive liver disease in over 60% of infected individuals culminating into cirrhosis and ultimately leading to liver failure and hepatocellular carcinoma (HCC). Chronic liver disease due to HCV infection is now the leading indication for livertransplantation both in Europe and the USA. Although the incidence of acute hepatitis C has decreased over the last decade, the number of individuals with HCV-related liver disease continues to rise and is projected to peak around year 2015. As such HCV infection imposes a significant burden on the already exhausted health resources, particularly in the developing counties where the infection is endemic and its incidence is increasing.

Epidemiological and phylogenetic evidence for patient-to-patient hepatitis C virus transmission during sclerotherapy of varicose veins

The aim of this study was to provide evidence for patient-to-patient nosocomial hepatitis C virus (HCV) transmission during sclerotherapy of varicose veins. Forty-three patients who had evidence of current infection by genotype 2 HCV have had sclerotherapy by the same physician. Based on this observation, a detailed epidemiological questionnaire on risk factors for HCV in genotype 2 infected patients was conducted. Seventeen sequences in the hypervariable region 1 (HVR1) of the HCV genome obtained from 17 HCV RNA positive patients with a past history of sclerotherapy, were compared with 17 sequences derived from genotype 2 patients with no past history of sclerotherapy, and with 25 sequences sampled from GenBank. Two hundred seven genotype 2 HCV infected patients were included. The main risk factors for HCV infection were transfusion (n = 76), drug use (n = 6), and sclerotherapy of varicose veins (n = 62 including 43 (20.8%) by the same physician), other or unknown (n = 76). These sclerotherapy sessions were carried out in the 1980s for many years. Five of these 43 patients had jaundice within a few weeks after a sclerotherapy session. Sequence analysis of HVR1 from 17 patients who had sclerotherapy by the same physician revealed that they were all infected with HCV genotype 2c. The phylogenetic tree indicated clustering of the patients with a past history of sclerotherapy. The method by which infection was likely to have been transmitted was probably the use of a single vial for multiple patients. This study provides strong evidence that sclerotherapy of varicose veins is a risk factor for HCV infection.

Protection of healthcare workers from bloodborne pathogens

PURPOSE OF REVIEW

For decades, healthcare workers have been known to be at risk from acquiring a variety of bloodborne pathogen infections as a result of occupational exposure. Primary prevention of exposures, as recommended by universal precautions guidelines, remains the cornerstone of protecting healthcare workers. Nonetheless, a substantial number of parenteral exposures continue to occur. Updated developments are summarized here, and recommendations for the protection of healthcare workers from bloodborne pathogens are provided.

RECENT FINDINGS

The predominant evidence suggests that total percutaneous injuries have decreased over the last decade. Thoughtful adherence to universal precautions remains the primary means of preventing occupational exposures and thus of reducing occupational risk of infection with bloodborne pathogens. A number of studies have provided additional evidence for the efficacy of safety devices in reducing specific subsets of injuries when combined with education and administrative interventions. Barriers to and positive predictors of universal precautions compliance have been identified. Postexposure prophylaxis remains the second line of defense; several authorities have now recommended three antiretroviral agents in this setting.

SUMMARY

In summary, almost two decades of experience with universal/standard precautions has resulted in a decrease in parenteral injuries, but much work remains to be done. Vaccines, effective infection control procedures, safer procedures, and safer devices will all be necessary, along with a better understanding of factors that influence healthcare worker behaviors that result in injury. In addition, a number of issues relating to the postexposure management of occupational exposures with bloodborne pathogens need to be better understood.

Hepatitis C virus prevalence and outcomes among injecting drug users on opioid replacement therapy

OBJECTIVES

To determine hepatitis C virus (HCV) prevalence among injecting drug users (IDUs) receiving opioid replacement therapy in a referred office setting, and assess potential needs for hepatitis C treatment and care.

METHODS

Data were collected on 178 IDUs receiving opioid replacement therapy who underwent clinical assessment between January 2002 and June 2003. Standard clinic protocols included HCV and hepatitis B virus (HBV) serology, liver biochemistry and HCV RNA analysis for patients with a positive HCV antibody and normal alanine aminotransferase (ALT) levels.

RESULTS

HCV prevalence was 75.3%, similar for males (75.5%) and females (74.4%), and increased with age from 60.8% for 19-30 years to 93.9% above 40 years. Among patients with HCV antibodies and no prior HCV antiviral therapy (n = 130), 53.1% had normal ALT levels and 25.4% were HCV-RNA negative. Older patients were more likely to have normal ALT levels (P = 0.02), and be HCV-RNA negative (P = 0.02). Younger patients were more likely to have been HBV vaccinated (P < 0.001), however, were less likely to have either vaccine or natural immunity (P = 0.006). Of 97 patients with probable chronic HCV infection, 58 patients met pre-liver biopsy criteria for HCV treatment, 34 had relative contraindications to treatment and 6 had been referred for treatment assessment.

CONCLUSION

Clinical characterization in a setting of high HCV prevalence has enabled the differentiation of patients into groups with no evidence of HCV viraemia, with chronic HCV infection, and those most appropriate for HCV treatment referral. These clinical assessments along with appropriate referral should be instituted in drug dependency treatment settings.

Outbreak of hepatitis C virus infection in an outpatient clinic

BACKGROUND

From January through September 2001, seven patients were admitted to Fukaya Red Cross Hospital with typical clinical manifestations of acute hepatitis. Six were outpatients of the clinic, which is located near the hospital. An extensive survey of clinic outpatients conducted by the local health department revealed six more new acute hepatitis cases during this period.

METHODS

A case control study was carried out to identify potential risk factors for infection. In total, 1946 outpatients with clinic records were scheduled to undergo hepatitis C virus (HCV)-antibody testing. For the HCV-Ab positive patients, HCV-RNA was subtyped and quantified, and sequences of HCV hypervariable region 1 were determined.

RESULTS

Ultimately, 12 patients with acute hepatitis and two asymptomatic subjects were found to be a part of this outbreak. HCV isolates were divided into three major groups using phylogenetic tree analysis. Only a past history of visiting the clinic was significantly associated with acute hepatitis. The timing of the parenteral medical procedure at the clinic and the onset of acute hepatitis strongly suggested association of the two events.

CONCLUSIONS

Our findings suggest that nosocomial HCV infection can occur in an outpatient clinic, even in countries where post-transfusion hepatitis has been almost entirely eliminated.

Diagnosis of hepatitis C virus related acute hepatitis by serial determination of IgM anti-HCV titres

BACKGROUND/AIMS

We investigated whether serial determination of IgM to HCV core protein (HCV IgM) may be useful to identify acute hepatitis C (AHC) and to distinguish this disease from reactivation of chronic hepatitis C (r-CHC).

METHODS

We enrolled 35 consecutive patients with AHC identified by seroconversion to anti-HCV and 31 consecutive patients who had been anti-HCV positive for at least six months at the time of reactivation. Titres of HCV IgM were calculated as Index values by a commercially available enzyme immunoassay.

RESULTS

During the early phase of the illness we observed a wide variation in the HCV IgM Index values in all patients in the AHC group and consistent values in all cases in the r-CHC group. The HCV viral load determined soon after the onset of symptoms was of no use in identifying AHC.Twenty-three patients in the AHC group were observed as outpatients for 6-30 months; of these, 10 became plasma HCV-RNA negative within the third month of observation, but three showed a subsequent reactivation of HCV infection.

CONCLUSIONS

Our data indicate that the detection of high and variable titres of HCV IgM in the early phase of the illness may identify acute hepatitis C and allow early antiviral treatment.

Hepatitis C in haemophilia: lights and shadows

Hepatitis C is a major cause of morbidity and mortality in haemophiliacs who received clotting factor concentrates before the availability of virus-inactivated factors in the mid-1980s. Early studies gave conflicting indications as to the severity of hepatitis C (originally termed non-A non-B hepatitis), as mild, slowly progressive hepatitis was documented in several infants and young adults with haemophilia who were examined with repeat liver biopsies, whereas more progressive hepatitis and cirrhosis was documented in others. One major point of dispute was whether these discrepancies could in part be accounted for by epidemiological differences among studies, as hepatitis C acquired early in life may initially run a benign course and later worsen owing to spontaneous recrudescence of hepatitis or interference with such comorbidity factors as alcohol abuse or infection with the human immunodeficiency virus (HIV). In the mid 1990s, the latter infection overshadowed hepatitis C as a cause of death in this patient population. Because hepatocellular carcinoma is emerging as an important complication in haemophiliacs with long-standing hepatitis C virus (HCV) infection who survived HIV infection, and because of recent advances in treating HIV, morbidity and mortality associated with chronic hepatitis C have regained emphasis amongst haemophiliacs. The development of newer interferon-based therapies provides an opportunity for modifying the natural history of HCV infection in a substantial number of haemophilic patients.

The hepatitis C virus genotype and subtype frequency in hepatitis C virus RNA-positive, hepatitis C virus antibody-negative blood donors identified in the nucleic acid test screening program in Poland

BACKGROUND

Since 2002, blood donors in Poland have been tested not only for hepatitis C virus antibodies (anti-HCV) but also for HCV RNA or HCV core antigen. This screening program identifies asymptomatic, recently infected individuals with no anti-HCV (in the "window period"). The aim of this study was to compare HCV genotype and subtype distribution in window-period (wp) donors, anti-HCV-positive donors, and chronic hepatitis C (CHC) patients.

STUDY DESIGN AND METHODS

A total of 2.37 million donors were investigated for HCV RNA, and 340,000 for HCV core antigen. HCV genotypes and subtypes were investigated in 50 HCV RNA-positive, anti-HCV-negative donors; in 70 anti-HCV-positive donors; and in 170 CHC patients. Re-questioning of wp donors for probable risk factors was introduced.

RESULTS

HCV RNA was detected in 50 donors of 2.71 million (1:54,200) anti-HCV-negative blood donations. Of these 50 donors, 36 percent exhibited Subtype 1b, whereas Subtypes 3a and 4c/d were identified in 40 and 14 percent, respectively. In anti-HCV-positive donors and CHC patients, the frequency of Subtype 1b was significantly higher (75.7 and 85.3%, respectively); in both groups the lower frequency of Subtypes 3a (14.3 and 10.6%, respectively) and 4c/d (4.3 and 1.2%, respectively) was found. The probable source of infection was identified in 9 wp donors.

CONCLUSIONS

The frequency of wp donors is 18.5 per 1 million. The unexpected high frequency of Genotype 4 and Subtype 3a and the low frequency of Subtype 1b was observed in wp donors compared to anti-HCV-positive individuals. Additional epidemiologic questioning introduced after HCV RNA detection may help to identify infection source.

Hepatitis C: What is the nature of the problem?

This review concentrates on the natural history of the infection. The virology and epidemiology of the disease are covered elsewhere. There are a number of inherent difficulties in studying the outcome of HCV infection: the onset is often not recognized, it can be asymptomatic, the progression is slow and patients may have had treatment. However some insights in recent years have been made.