Routes of infection, viremia, and liver disease in blood donors found to have hepatitis C virus infection

Comparison of demographic and donation profiles and transfusion-transmissible disease markers and risk rates in previously transfused and nontransfused blood donors

BACKGROUND

Increasing concern about transfusion transmission of variant Creutzfeldt-Jakob disease has resulted in indefinite deferral of transfused donors in France and the UK. Little is known, however, about the impact of indefinite deferral of transfused donors on blood safety and availability in the US.

STUDY DESIGN AND METHODS

Data were collected on allogeneic donations at five US blood centers during 1991 through 2000. Donation characteristics, prevalence, and incidence of human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) were compared between transfused and nontransfused donors. Unreported deferrable risk (UDR) and reasons to donate were evaluated with data from a mail survey.

RESULTS

Transfusion history was reported by 4.2 percent of donors. Prevalence and incidence of HIV and HBV were comparable between transfused and nontransfused donors. Although HCV incidence was similar in both groups, HCV prevalence was nearly three times higher in transfused than in nontransfused first-time donors. UDR and reasons to donate were similar in the two groups, except transfused donors were less likely to donate for screening test results (odds ratio, 0.5; 95% confidence interval, 0.3-0.8).

CONCLUSION

Transfused and nontransfused donors had similar viral incidence and comparable UDR, suggesting that indefinite deferral of transfused donors would unlikely improve blood safety. Until more is known about the prevalence and transfusion transmissibility of emerging agents, indefinite deferral of previously transfused donors in the US does not appear warranted.

Epidemiology, Diagnosis, and Treatment of Chronic Hepatitis C

The hepatitis C virus (HCV) is a leading cause of chronic liver disease, cirrhosis, and hepatocellular carcinoma and is also a common indication for liver transplantation. Interferon alfa monotherapy leads to a sustained virologic response in only 10% to 15% of HCV-infected patients. The sustained virologic response rates can be increased to approximately 40% with interferon alfa-2b and ribavirin combination therapy for up to 48 weeks. However, recent clinical trials demonstrated that pegylated interferon in combination with ribavirin can improve the response rates even further, with more than 50% of patients having a sustained virologic response to treatment. Although new therapies are emerging, significant progress must be made to reduce the morbidity and mortality from HCV infection.

Intranasal cocaine use does not appear to be an independent risk factor for HCV infection

AIMS

To determine the prevalence of HCV infection among intranasal cocaine users and evaluate underlying parental risk factors.

DESIGN, SETTING AND PARTICIPANTS

A cross-sectional study evaluated prospectively 60 patients admitted to a chemical dependency unit.

MEASUREMENTS

A standardized questionnaire was designed to obtain epidemiological data. Aminotransferases and anti-HCV antibodies were determined. Anti-HCV antibody positivity was confirmed by polymerase chain reaction (PCR).

FINDINGS

Fifteen (25%) patients of 60 tested intranasal cocaine users were anti-HCV positive. Ten (75%) of them had detectable HCV-RNA. Comparison between 15 anti-HCV positive and 45 anti-HCV negative patients showed significant differences in mean age (35 versus 27 years), estimated time of drug use (10 versus 4 years), rate of elevated ALT and/or AST (60% versus 16%) and presence of parenteral risk factors (100% versus 7%). Comparison between patients with and without elevated aminotransferases showed significant difference in mean duration of drug use (8 versus 5 years) and rate of anti-HCV positivity (56% versus 14%). Among 15 anti-HCV positive patients, HCV-RNA was detectable in all with elevated aminotransferases and only one of six with normal aminotransferases (100% versus 17%).

CONCLUSIONS

While there was a high prevalence of anti-HCV antibodies in this sample of intranasal cocaine users, the infection was highly correlated with the presence of intravenous (i.v.) drug use and duration of drug use. In this sample, therefore, intranasal cocaine use alone was not an important risk factor for HCV infection.

Human immunodeficiency virus (HIV) and hepatitis C virus (HCV) in a Northern Alberta population

OBJECTIVE

To describe the demographics and estimate the prevalence of hepatitis C virus (HCV) in a cohort of Human Immunodeficiency Virus (HIV) positive patients in Northern Alberta.

METHODS

A cross-sectional (prevalence) study was performed on a cohort of HIV-positive patients. HCV testing was not widely available until December 1989, and the more sensitive, second generation immunoassay was not available until 1992. To reduce the effect of testing bias, we restricted consideration of HCV status to patients first seen January 1, 1992 onward.

RESULTS

Forty-four percent of patients in the whole cohort were tested for HCV (564/1,276) and 62% (505/809) of patients entered since January 1, 1992 were tested for HCV. During the period January 1, 1992-December 31, 1999, the prevalence of HCV in our cohort of northern Alberta HIV-positive patients was at least 37.9% (307/809) and was 60.8% (307/505) among those who were tested for HCV in 1992 or later. The mean age of the co-infected group was 33.6 years, 66.1% were male, 91.2% were injection drug users (IDUs), 56.8% were Caucasian, and 40.0% were Aboriginal. A statistically significant difference was found between the HCV-negative cohort, the HCV co-infected cohort, and the HCV-untested cohort for the following variables: risk behaviour, gender, ethnic status, death, occurrence of an AIDS-defining illness (p < 00.0001), and mean baseline CD4 cell count (p = 0.002).

CONCLUSION

A high proportion of the HIV-infected IDUs was co-infected with HCV. Compared to the HCV-negative group, the co-infected group appears to have had less advanced HIV disease. This is likely a reflection of more recent HIV infection in the HCV co-infected group.

[Interferon-alpha and ribavirin therapy on chronic hepatitis C virus infection: the experience of Rio Grande do Sul State Health Department, Brazil]

BACKGROUND

Chronic infection by hepatitis C virus is an important public health issue.

AIMS

To assess the effectiveness of a combination therapy with interferon-alpha plus ribavirin and to identify predictive factors of response in adult patients with chronic hepatitis C in a public drug supply program.

PATIENTS AND METHODS

A retrospective study of consecutive records of 400 patients with chronic hepatitis C treated with interferon-a plus ribavirin therapy, as part of a health program conducted by the Department of Health of the State of Rio Grande do Sul, Porto Alegre, RS, southern Brazil, between 1999 and 2000, was carried out.

RESULTS

Sex distribution was similar, and the average age was 46.5 +/- 10.3 years. Response at the end of the treatment was observed in 49% of patients, and sustained response was observed in 32% of them. Sustained response was significantly higher in females and in patients infected by genotypes other than 1. We did not observe significant differences in terms of age or histological stage and activity score.

CONCLUSION

In adult patients with chronic hepatitis C, combination therapy with interferon-alpha plus ribavirin was effective in one third of patients. Higher rates of response were observed in women and in patients infected by genotypes other than 1.

A potential hidden source of hepatitis C infection among noninjecting drug users

Hepatitis C virus (HCV) is a major cause of chronic liver disease in the United States and worldwide. It is primarily transmitted through blood-to-blood contact with an infected individual. HCV is hyperendemic among injection drug users (IDUs), who contract the virus through contaminated syringes and drug preparation equipment shared with other IDUs. The prevalence of HCV is also high, to a lesser degree, among noninjection drug users, many of whom report no identifiable HCV risk exposures. This article reviews the epidemiological and virological evidence bearing on a potential hidden source of HCV infection among noninjection drug users: namely, the oral or intranasal transmission of HCV through the sharing of noninjection drug-use implements such as pipes or straws. While there is some epidemiological evidence supporting both oral and intranasal HCV transmission, most studies are hampered by methodological limitations. Thus, there is a need for prospective studies designed specifically to examine these potential routes of transmission. Current biological evidence does not refute either oral or intranasal transmission as possible sources of HCV infection, although more research is needed in the areas of oronasal HCV pathogenesis and the detection of HCV RNA in the nasal mucosa of intranasal drug users.

Risk factors for hepatitis C infection among sexually transmitted disease-infected, inner city obstetric patients

Objective: To test the hypothesis that our inner city obstetric patients who have been infected with sexually transmitted diseases (STDs) will have a higher prevalence of hepatitis C virus infection than the general population and to identify specific risk factors and high-risk groups.

Methods: All patients in our prenatal clinic (July 1997–April 1999) who tested positive for one or more STDs were asked to return for hepatitis C antibody testing. Medical charts of all patients who returned for hepatitis C testing were reviewed.

Results: A total of 106 patients with STDs were tested for hepatitis C. Positive screening tests for anti-hepatitis C antibody were found in 6.6% (7/106) of the patients (95% CI = 2.7–13.1%). This frequency is significantly higher than the hepatitis C prevalence (1.8%) in the general United States population (p = 0.006). Multiple logistic regression analysis confirmed only older age (p = 0.016) and positive HIV status (p = 0.023) to be significant predictors of hepatitis C infection.

Conclusions: Inner city STD-infected obstetric patients are at high risk for hepatitis C infection compared with the general population. Increasing age and HIV-positive status are risk factors which are significantly associated with hepatitis C infection.

Detection of hepatitis C virus in the nasal secretions of an intranasal drug-user

Background

One controversial source of infection for hepatitis C virus (HCV) involves the sharing of contaminated implements, such as straws or spoons, used to nasally inhale cocaine and other powdered drugs. An essential precondition for this mode of transmission is the presence of HCV in the nasal secretions of intranasal drug users.

Methods

Blood and nasal secretion samples were collected from five plasma-positive chronic intranasal drug users and tested for HCV RNA using RT-PCR.

Results

HCV was detected in all five blood samples and in the nasal secretions of the subject with the highest serum viral load.

Conclusions

This study is the first to demonstrate the presence of HCV in nasal secretions. This finding has implications for potential transmission of HCV through contact with contaminated nasal secretions.

Possible hepatotoxicity of chronic marijuana usage

CONTEXT

Hepatotoxicity is a potential complication from the usage of various illicit drugs, possibly consequent to their liver metabolism, but information on this is scarce in the medical literature.

OBJECTIVE

To study the occurrence of clinical and laboratory hepatic alterations in chronic marijuana users, from the use of marijuana on its own or in association with other legal or illicit drugs.

TYPE OF STUDY

transversal study

SETTING

Hospital Espírita de Marília, Marília, São Paulo, Brazil

PARTICIPANTS

The study was made among 123 patients interned in the Hospital Espírita de Marília from October 1996 to December 1998, divided into 3 groups: 26 (21%) using only marijuana, 83 (67.5%) using marijuana and crack, and 14 (11.4%) consuming marijuana and alcohol. PROCEDURES AND MAIN MEASUREMENTS: Patients were examined clinically with special emphasis on types of drugs used, drug intake route, age when consumption began, length and pattern of usage, presence of tattooing, jaundice, hepatomegaly and splenomegaly. Serum determinations of total proteins, albumin, globulin, total and fractions of bilirubin, aspartate (AST) and alanine (ALT) aminotransferases, alkaline phosphatase (AP), gamma-glutamyltransferase and prothrombin activity were performed.

RESULTS

Among users of only marijuana, hepatomegaly was observed in 57.7% and splenomegaly in 73.1%, and slightly elevated AST (42.3%), ALT (34.6%) and AP (53.8%). The three groups did not differ significantly in the prevalence of hepatomegaly, splenomegaly and hepatosplenomegaly. The group using both marijuana and alcohol showed the highest prevalence of alterations and highest levels of aminotransferases. Mean AP levels were above normal in all groups.

CONCLUSIONS

Chronic marijuana usage, on its own or in association with other drugs, was associated with hepatic morphologic and enzymatic alterations. This indicates that cannabinoids are possible hepatotoxic substances.

Hepatitis C Infection: A Clinical Review

Nearly three million persons in the United States are viremic with hepatitis C (HCV). Despite a decreasing incidence of HCV in this country, the prevalence of HCV-related chronic liver disease is increasing. Most infections in the United States are acquired by intravenous drug use. The chronicity rate of HCV is high, reaching 85% in some populations, and the risk of progression to advanced liver disease is as high as 20% within twenty years of infection. Host factors like alcohol use accelerate the rate of progression. The enzyme immunoassay is the preferred initial test for diagnosis; the third generation assay has greater than a 99% specificity in immunocompetent patients. Barring contraindications, the standard of care for treatment of chronic HCV has become pegylated interferon and ribavirin. With this therapy, the cure rate for treatment-naïve patients is about 55%, but rates are higher in certain groups. Common side effects of therapy include neuropsychiatric symptoms, influenza-like symptoms and hematological abnormalities.

Increased mortality associated with HTLV-II infection in blood donors: a prospective cohort study

Background

HTLV-I is associated with adult T-cell leukemia, and both HTLV-I and -II are associated with HTLV-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Several published reports suggest that HTLV-I may lead to decreased survival, but HTLV-II has not previously been associated with mortality.

Results

We examined deaths among 138 HTLV-I, 358 HTLV-II, and 759 uninfected controls enrolled in a prospective cohort study of U.S. blood donors followed biannually since 1992. Proportional hazards models yielded hazard ratios (HRs) for the association between mortality and HTLV infection, controlling for sex, race/ethnicity, age, income, educational level, blood center, smoking, injection drug use history, alcohol intake, hepatitis C status and autologous donation. After a median follow-up of 8.6 years, there were 45 confirmed subject deaths. HTLV-I infection did not convey a statistically significant excess risk of mortality (unadjusted HR 1.9, 95%CI 0.8–4.4; adjusted HR 1.9, 95%CI 0.8–4.6). HTLV-II was associated with death in both the unadjusted model (HR 2.8, 95%CI 1.5–5.5) and in the adjusted model (HR 2.3, 95%CI 1.1–4.9). No single cause of death appeared responsible for the HTLV-II effect.

Conclusions

After adjusting for known and potential confounders, HTLV-II infection is associated with increased mortality among healthy blood donors. If replicated in other cohorts, this finding has implications for both HTLV pathogenesis and counseling of infected persons.

[Identification of the cutoff value for serum alanine aminotransferase in hepatitis C screening of patients with chronic renal failure on hemodialysis]

The patients with chronic renal failure in hemodialysis present low levels of serum alanine aminotransferases. In order to establish a better cutoff value for ALT in hepatitis C screening of hemodialysis patients, the ALT levels were measured monthly in 235 patients, being excluded those that presented average above the upper limit of normality. The cutoff value was identified by construction of a ROC curve (receiver operating characteristic). Among 202 patients, 15 (7.4%) presented antibodies to hepatitis C virus (anti-HCV) and 187 (92.6%) were anti-HCV negative, with an ALT average of 0.7 and of 0.5 from ULN (p <0.0001), respectively. The better cutoff value for ALT was at 0.6 from ULN, with sensitivity of 67% and specificity of 75% in anti-HCV screening. These results suggest that ULN of ALT could be reduced for 60% from conventional limit, when we are evaluating patients with CRF in hemodialysis.

Neuropsychiatric side effects of HCV therapy and their treatment: focus on IFN alpha-induced depression

Psychiatric disorders, particularly depression, and substance-use disorders (SUDs) are common comorbidities in patients who have chronic hepatitis C virus (HCV) infection. Patients who are infected with HCV who are treated with interferon alfa (IFNalpha) are also at significant risk for IFNalpha-induced depression (incidence, ~20-30%) and other neuropsychiatric side effects that can affect treatment adherence, require dose reduction or discontinuation, and impact patient quality of life adversely. Because psychiatric illness and SUD comorbidities are so common, patients who have hepatitis C should be screened for these disorders. If these disorders are present, patients should be referred to a mental health care provider for appropriate treatment before therapy with IFNalpha is considered. Having a comanagement model of care that involves mental health care providers should help identify appropriate candidates for IFNalpha therapy. If preexisting depression responds to antidepressant treatment IFNalpha therapy can then be initiated. Patients who have other active psychiatric disorders can probably be offered IFNalpha therapy safely with appropriate monitoring and management involving a mental health care professional; however, there is a paycity of research in this area, and the few published studies have small sample sizes. If depression develops during IFNalpha therapy, most patients respond to treatment with selective serotonin-reuptake inhibitors, often allowing patients to continue receiving IFNalpha therapy. In addition to screening patients and treating those who have psychiatric disorders before IFNalpha therapy is started, early recognition of psychiatric disorders and neuropsychiatric side effects during IRNalpha therapy through continued screening and monitoring, with appropriate management, can potentially maximize HCV treatment adherence and possibly improve antiviral therapy outcomes.

Risk factors for HCV infection among blood donors confirmed to be positive for the presence of HCV RNA and not reactive for the presence of anti-HCV

BACKGROUND

In 1999, NAT of blood donations was implemented to detect "window-period" infections. Blood donors who have confirmed NAT results positive for the presence of HCV in the absence of anti-HCV are likely to have been recently infected. Of over 26.8 million donations tested between March 3, 1999, and March 31, 2003, 810 were HCV-reactive by NAT. A subset of these donors was assessed for recent exposure risk.

STUDY DESIGN AND METHODS

All anti-HCV- blood donors with reactive, unconfirmed HCV NAT results were invited to participate in a study that included an extensive demographic and risk questionnaire. Confirmed HCV+ cases were compared to HCV- (falsely positive) controls for histories of potential risk factors during the 6 months before donation.

RESULTS

Recent injection drug use (IDU) was independently associated with HCV infection (29.2% vs. 0% of cases vs. controls, p < 0.001). In addition, likely sources were identified for three other cases (4.6%), including occupational exposure, sexual contact with an HCV-infected partner (who was an IDU), and perinatal exposure, none of which was known to the donors at the time of donation. Incarceration was independently associated with HCV infection among the group not reporting IDU and after removal of the three donors with likely sources of risk (14.6% vs. 1.3% of cases vs. controls, p < 0.001).

CONCLUSIONS

A likely risk, primarily IDU, was found for 43 percent of HCV+ donors whose infections were identified solely by NAT. Because the maximum efficiency of the donor history questions may have been reached, NAT will continue to be an important measure to interdict recently infected blood donors.

Two antiviral compounds from the plant Stylogne cauliflora as inhibitors of HCV NS3 protease

The 70% aq methanolic extract of the Peruvian plant Stylogne cauliflora was found to contain two novel oligophenolic compounds SCH 644343 (1) and SCH 644342 (2), which were identified as inhibitors of HCV NS3 protease. The structure of 1 and 2 was established based on high-resolution NMR studies. Compound 1 inhibited HCV NS3 protease with an IC(50) of 0.3 microM, while compound 2 showed an IC(50) of 0.8 microM.

Low incidence and prevalence of hepatitis C virus infection among sexually active non-intravenous drug-using adults, San Francisco, 1997-2000

BACKGROUND

The rate of sexual transmission of hepatitis C virus (HCV) is debated.

GOAL

The goal was to measure the risk of sexual transmission of hepatitis C virus (HCV) in a sexually active population.

STUDY DESIGN

Sexual behaviors and HCV antibody status were measured in persons seeking repeat HIV testing in San Francisco from October 1997 through March 2000.

RESULTS

Among 981 repeat testers, the prevalence of HCV antibody was 2.5%. Among men who have sex with men who denied intravenous drug use (n=746), factors associated with HCV antibody positivity include age greater than 50 years (odds ratio [OR], 8.5; 95% confidence interval [CI], 2.6-27.7), HIV infection (OR, 5.7; 95% CI, 1.6-20.6), and being nonwhite (OR, 3.3; 95% CI, 1.1-10.0). HCV antibody positivity was not associated with sexual risk behaviors. In 576.6 person-years of observation, no new HCV seroconversions occurred (incidence=0 per 100 person-year; 95% CI, 0-.6), whereas 6 new herpes simplex virus-2 infections (2.8 per 100 person-years) and 10 new HIV infections (1.8 per 100 person-years) occurred.

CONCLUSION

The absence of new HCV infections in this sample supports the hypothesis that the risk of sexual transmission of HCV is low.

Hepatite C: prevalência e fatores de risco entre portadores do VIH/SIDA em Belém, Pará, na Amazônia brasileira

Este trabalho objetivou investigar a prevalência de infecção pelo vírus da hepatite C e identificar possíveis fatores de risco para sua transmissão, em 406 indivíduos portadores do vírus da imunodeficiência humana, maiores de dezoito anos de idade, atendidos na rede pública de saúde da cidade de Belém, Pará, situada na Amazônia brasileira. Os exames referentes ao anti-VHC foram realizados pelo método de Elisa e a pesquisa do VHC RNA através da reação de polimerase em cadeia. A prevalência de infecção, atual ou pregressa, pelo vírus da hepatite C foi de 16% (IC: 12,4 - 19,6). A análise multivariada mostrou associação do vírus C com as variáveis idade, cujo risco significante recaiu no grupo com cinqüenta ou mais anos (OR=9,75), antecedente de transfusão de sangue (OR=4,74) e uso de droga ilícita injetável (OR=149,28). A prevalência do vírus da hepatite C entre os usuários de drogas injetáveis foi de 83,7% e de 22,1% na população de transfundidos. Estes resultados indicam a efetiva transmissão do vírus C através da exposição percutânea e reafirmam o grande potencial de risco para hepatite C contido no uso injetável de drogas ilícitas.

Sharing of noninjection drug-use implements as a risk factor for hepatitis C

This study examined sharing noninjection drug implements as a risk factor for hepatitis C (HCV) infection among women drug users (n = 123) with no history of drug injection. Participants were street-recruited from East Harlem, New York City, between October 1997 and June 1999. Participants were administered a survey measuring risk factors for HCV. Prevalence of HCV and HIV infections was 19.5% and 14.6%, respectively. Multiple logistic regression determined significant associations between sharing noninjection drug-use implements and HCV infection. "Ever shared both oral and intranasal noninjection drug implements" was independently associated with HCV infection [Odds ratio (OR) 2.83; Confidence interval (CI) 1.04, 7.72; p = 0.04]; "ever shared noninjected heroin implements with an injector" was a trend (OR 3.06; CI .85, 10.79; p = 0.08). The strongest association between sharing noninjection drug-use implements and HCV infection was found among HIV positive individuals (chi2 = 8.8, 1 d.f., p < 0.01). These findings, if supported by future research, indicate a need to reassess policies regarding HCV infection.

Influence of maternal human immunodeficiency virus (HIV) co-infection on vertical transmission of hepatitis C virus (HCV): a meta-analysis

BACKGROUND

Maternal co-infection with human immunodeficiency virus (HIV) has been implicated as a potentially important co-factor for enhanced vertical transmission of hepatitis C virus (HCV). In previous reports, however, methodological issues (notably small sample sizes) have limited accurate evaluation of the contribution of maternal co-infection with HIV on the risk of vertical transmission of HCV.

METHODS

A systematic review and subsequent meta-analysis of current published and unpublished reports was performed. Odds ratios (OR) and 95% CI for individual studies were calculated with maternal HIV serostatus as the exposure measure and HCV vertical transmission as the outcome measure. Overall summary estimates were then calculated using a random effects model that estimates a weighted average of OR from individual studies.

RESULTS

In total, 2382 infants from 10 studies were included in an analysis of HCV-infected mothers (defined by anti-HCV+ antibody assays) with and without concomitant HIV infection. The risk estimate (OR) of HCV vertical transmission was 2.82 (95% CI: 1.78-4.45; P = 0.00001) from anti-HCV+/HIV+ co-infected mothers compared with anti-HCV+/HIV- mothers. In a subanalysis of 1327 infants born to viraemic (HCV RNA+) mothers, the risk estimate of HCV vertical transmission was 1.97 (95% CI: 1.04-3.74; P = 0.04) from HCV viraemic/HIV+ co-infected mothers compared with HCV viraemic/HIV- mothers.

CONCLUSIONS

Results from this meta-analysis of observational studies suggest that the risk of HCV vertical transmission is higher in infants born to HIV co-infected mothers.

Natural history and epidemiology of hepatitis C

The high incidence of hepatitis C virus (HCV) makes it one of the greatest health threats facing the world today. Hepatitis C is the most common blood-borne infectious disease in the United States, and evidence demonstrates that if the disease is not contained it will continue to spread and the death rate from hepatitis C will rise to a level far greater than that of AIDS. The epidemiological patterns of hepatitis C transmission will be reviewed.

Risks of blood transfusion

OBJECTIVE

To review the current status of risks of blood transfusion.

DATA SOURCES, EXTRACTIONS, AND SYNTHESIS

English-speaking literature, literature search using key works, human data, and follow-up with key bibliographic citations.

CONCLUSIONS

Substantial advances have been achieved in blood safety during the last 20 yrs, particularly for transfusion-transmitted viral infections. Currently, the most serious known risks from blood transfusion are administrative error (leading to ABO-incompatible blood transfusion), transfusion-related acute lung injury, and bacterial contamination in platelet products. Emerging pathogens, such as West Nile virus infection emphasize the need for implementation of proactive strategies, such as pathogen inactivation technologies, as well as reactive strategies, such as nucleic acid testing, to ensure continued advances in blood safety.

Tattooing and transfusion-transmitted diseases in Brazil: a hospital-based cross-sectional matched study

BACKGROUND

Presence of tattoos has been a criterion for temporary deferral of blood donors. Scientific evidence remains equivocal regarding the association between tattooing and transfusion-transmitted diseases (TTDs).

METHODS

A cross-sectional matched study was undertaken among adults attending a Brazilian hospital and blood bank. The exposure of interest was having at least one permanent tattoo, and the outcomes were the presence of serological markers for the following TTDs: hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV) infections, syphilis, and Chagas' disease. Exposed and unexposed subjects were matched on age, sex, and main clinical complaint. Associations were assessed by odds ratios (ORs), adjusted for confounders by unconditional logistic regression.

FINDINGS

The study recruited 345 subjects, 182 with tattoos. Having a tattoo was associated with HCV (OR: 6.41; 95% confidence interval (CI) 1.29, 31.84), and with having at least one positive test for any TTD (OR: 2.05, 95% CI: 1.11, 3.81). No statistically significant associations were found between tattooing and HBV or HIV infection, syphilis or Chagas' disease, but these results are inconclusive given the large CI obtained.

INTERPRETATION

Having a tattoo is not an important indicator for testing positive for a TTD, except for HCV infection. Taking into consideration the increasing prevalence of tattooing in the general population, the absolute need of a safe and sustainable blood supply and optimization of the cost-effectiveness of screening blood donors, further research on tattoos is urgently required.

Hepatitis C and B-cell lymphoma

The association between the hepatitis C virus and B-cell non-Hodgkin's lymphomas is controversial. We review the epidemiological evidence behind the association, and look at the reasons behind the variation in study findings. There is increasing evidence of the pathogenesis of hepatitis C-associated lymphoma. Treatment of the hepatitis C virus with antiviral therapy may lead to the regression of some low-grade lymphomas. The management of other hepatitis C-associated lymphomas is similar to that of conventional lymphoma, although viral reactivation and subsequent immune reconstitution hepatitis can complicate chemotherapy.

Factors associated with hepatitis C virus infection in injection and noninjection drug users in Italy

We describe the prevalence of hepatitis C virus (HCV) infection among noninjection users of heroin in Italy and compare the prevalence of HCV infection among noninjection drug users (NIDUs) and injection drug users (IDUs). Multiple logistic regression analysis of data from NIDUs showed that hepatitis B virus (HBV) infection status was the only independent predictor of HCV seroprevalence. Among IDUs, the number of years of drug use and HBV and human immunodeficiency virus infection status were independent predictors of HCV seropositivity. We found an HCV infection prevalence of 20% among NIDUs. This rate was much lower than that for IDUs, who are 11 times more likely to have antibodies against HCV. The prevalence of HCV infection was much higher than that of HBV infection among the IDUs. In contrast, the prevalence of HBV infection was slightly higher than that of HCV infection among unvaccinated NIDUs. The prevalence of HCV infection among long-term IDUs approached true population saturation; among long-term NIDUs, however, it appeared to plateau at approximately 40%. Additional research on HCV infection among NIDUs is needed to develop a strategic prevention program for this patient subgroup.

Managing occupational risks for hepatitis C transmission in the health care setting

Hepatitis C virus (HCV) infection is a significant contemporary health problem in the United States and elsewhere. Because it is primarily transmitted via blood, hepatitis C infection presents risks for both nosocomial transmission to patients and occupational spread to health care workers. Recent insights into the pathogenesis, immunopathogenesis, natural history, and treatment of infection caused by this unique flavivirus provide a rationale for the use of new strategies for managing occupational hepatitis C infections when they occur. This article reviews this developing information. Recently published data demonstrate success rates in the treatment of "acute hepatitis C syndrome" that approach 100\%, and although these studies are not directly applicable to all occupational infections, they may provide important clues to optimal management strategies. In addition, the article delineates approaches to the prevention of occupational exposures and also addresses the difficult issue of managing HCV-infected health care providers. The article summarizes currently available data about the nosocomial epidemiology of HCV infection and the magnitude of risk and discusses several alternatives for managing exposure and infection. No evidence supports the use of immediate postexposure prophylaxis with immunoglobulin, immunomodulators, or antiviral agents. Based on the very limited data available, the watchful waiting and preemptive therapy strategies described in detail in this article represent reasonable interim approaches to the complex problem of managing occupational HCV infections, at least until more definitive data are obtained.

Hepatitis C virus infection among noninjecting drug users in New York City

The prevalence of hepatitis C virus (HCV) infection among noninjecting drug users has been reported to be higher than in the general population, but the reasons for this observation remain unclear. Noninjecting drug users aged 15-40 years and who used drugs for no longer than 10 years were enrolled in the study. The participants were interviewed about risk behaviors and had specimens drawn for serological testing. Of 276 enrolled, 4.7% were infected with HCV. Drug users who had ever sniffed or snorted heroin in combination with cocaine were significantly more likely to be infected with HCV compared with those who never sniffed or snorted heroin with cocaine. No other drug use or sexual risk behaviors were found to be associated with HCV infection. These findings suggest that sniffing or snorting heroin with cocaine may explain the increase frequently found in HCV infection among noninjectors, but further studies are necessary.

Clinical aspects and outcomes of volunteer blood donors testing positive for hepatitis-C virus infection in Taiwan: a prospective study

BACKGROUND/AIM

The natural history of hepatitis-C virus (HCV) infection has been explored in volunteer blood donors, but not yet in hepatitis-B endemic areas. Whether previous or concurrent hepatitis-B virus (HBV) infection influences the natural history of HCV infection remains unknown. Thus, we followed the anti-HCV-positive blood donors who had past or concurrent HBV infection in Taiwan.

METHODS

From 1992 to 1993, 1588 anti-HCV reactive volunteer blood donors were referred to us from the Taipei Blood Center and 879 (55%) repeatedly reactive for anti-HCV were enrolled. Two hundred and forty-three donors (HCV RNA seropositive rate 49% by polymerase chain reaction (PCR)) received regular follow-ups (mean period: 4.9 years) with their liver disease status determined mainly by clinical and biochemical parameters, serum alpha-fetoprotein level and imaging studies. Hepatitis-C virus genotype and occult HBV infection were determined by PCR-based assays.

RESULTS

Of the initial 879 subjects, 250 (28%) had chronic hepatitis, nine (1%) had liver cirrhosis (LC) and two (0.2%) had hepatocellular carcinoma (HCC) already. In the 243 regularly followed donors, 30% had repeatedly normal serum alanine aminotransferase (ALT) and 70% had more than once elevated ALT. Cirrhosis developed in four (1.6%; follow-up period range: 2-6 years) and HCC in two (0.8%; follow-up period: 3 and 4 years, respectively). Distribution of HCV genotype and hepatitis-B surface antigen (HBsAg) did not differ between those with and those without elevation of ALT. Of the 15 donors with LC and/or HCC, only 1(7%) was positive for both HBsAg and HBV DNA and the other 14 were negative for both HBsAg and serum HBV DNA.

CONCLUSIONS

Incidentally detected hepatitis-C was progressive in a small proportion of anti-HCV-positive volunteer blood donors in Taiwan. Occult HBV infection played a minimal role in the development of LC in this donor population.

Prevalence of hepatitis C in a drug using and non-using welfare population

CONTEXT

Drug use is a primary route for the transmission of the Hepatitis C virus (HCV). A substantial proportion of welfare recipients have been shown to be substance abusers. In addition, federal legislation has imposed limits on the number of months individuals may receive benefits and has mandated most recipients to participate in a 'work activity' in exchange for benefits. HCV symptoms may inhibit welfare recipients' ability to seek and maintain employment.

OBJECTIVE

To assess the prevalence of HCV in a sample of Temporary Assistance to Needy Families (TANF) recipients and the effects of HCV antibody seropositivity on employability.

DESIGN, SETTING, AND PARTICIPANTS

The sample for this study consisted of 380 individuals participating in a longitudinal study of employment patterns among TANF recipients in Houston, TX, funded by the National Institute on Drug Abuse (NIDA). Private interviews regarding welfare receipt, employment, and drug use were conducted at intake into the study and at 4-month intervals for one year. Participants agreed to a one-time blood test. Blood samples were tested for the presence of HCV antibodies by enzyme linked immunoassay.

MAIN OUTCOME MEASURE

Employment status over time by HCV antibody status.

RESULTS

Overall, 12% of all participants tested positive for the presence of HCV antibodies. A significantly greater proportion of chronic drug users (31%) than non-drug users (4%) tested positive for the presence of Hepatitis C antibodies. Those who tested positive for hepatitis C had significantly lower rates of employment.

CONCLUSIONS

Potential infection with Hepatitis C may constitute an employment barrier for many welfare recipients.

Clinical management of HCV carriers with normal aminotransferase levels

An ad hoc committee appointed by the Italian Association for the Study of the Liver (AISF) proposed these Practice Guidelines for the management of HCV carriers with persistently normal aminotransferase levels. Only stringent ALT determinations will make it possible to distinguish these subjects from those in temporary biochemical remission. The overall prevalence in Italy has been estimated between 1.5 and 10.6%. HCV RNA quantitation and genotype determination are not predictors of the presence and severity of liver damage nor correlate with the outcome of the disease, and should not be used in clinical practice for the management and surveillance of HCV carriers with normal ALT. Only a minority of HCV carriers with normal ALT levels show a normal morphological picture (true 'healthy carriers'). Disease activity is mild in most cases; fibrosis is generally mild and cirrhosis is very rare. Histological activity, as monitored by sequential liver biopsies, seems to have very slow evolution. HCV carriers should not undergo liver biopsy on a routine basis. Liver biopsy can be reasonably proposed only in selected cases. Until the results of studies with PEG interferon plus ribavirin are available, HCV carriers should not receive antiviral treatment outside controlled experimental studies.

Evaluation of screening criteria to identify persons with hepatitis C virus infection among sexually transmitted disease clinic clients: results from the San Diego Viral Hepatitis Integration Project

BACKGROUND

The Centers for Disease Control and Prevention estimates that 1.8% of the US population is infected with hepatitis C virus (HCV), and most are unaware of their infection.

GOAL

The goal was to evaluate risk-based HCV screening criteria for clients attending an urban sexually transmitted disease (STD) clinic.

STUDY DESIGN

This was a cross-sectional study of HCV prevalence among all STD clinic clients during an 8-month period (September 1999 through April 2000) in San Diego, California.

RESULTS

HCV prevalence was 4.9% (165/3367). Clients who reported that they were injecting drug users (IDUs) were much more likely to be HCV-positive than other clients (51% versus 2%; P < 0.001). Selective screening of IDUs, sex partners of IDUs, and persons having received a blood transfusion before 1992 would have identified 70% of HCV-infected clients while screening only 12% of the clinic's attendees. The HCV prevalence among clients with a history of a bacterial STD (in the past 5 years) and no other major risk factors was only 2.5%.

CONCLUSION

In STD clinics, integrating risk-based screening into routine clinic services is an efficient way to identify HCV-infected persons.

Hepatitis C virus infection in the general population: a community-based study in West Bengal, India

Limited information is available about the prevalence and genotype distribution of hepatitis C virus (HCV) in the general population of India. A community-based epidemiologic study was carried out in a district in West Bengal, India. By a 1:3 sampling method, 3,579 individuals were preselected from 10,737 inhabitants of 9 villages of the district, of whom 2,973 (83.1%) agreed to participate. Twenty-six subjects (0.87%) were HCV antibody positive. The prevalence increased from 0.31% in subjects <10 years of age to 1.85% in those >or=60 years. No difference in prevalence between men and women was observed. Serum alanine aminotransferase (ALT) levels were elevated in 30.8% (8 of 26) of anti-HCV-positive subjects compared with 3.2% (94 of 2,947) anti-HCV-negative subjects (P <.001). HCV RNA was detectable in 80.8% (95% CI, 65.6%-95.91%) of the anti-HCV-positive subjects by reverse transcription-primed polymerase chain reaction (RT-PCR). The participants were HCV types 1b in 2 (9.5%), 3a in 8 (38.1%), 3b in 6 (28.6%), and unclassified in 5 (23.8%). Nucleotide sequencing and phylogenetic analysis assigned the unclassified type to genotype 3e. In conclusion, this study provides general population-based estimates of HCV prevalence, including genotypes, from a South Asian country. Although the prevalence of HCV infection in this population was lower than that reported from industrialized countries of the west, the total reservoir of infection is significant and calls for public health measures, including health education to limit the magnitude of the problem.

Hepatitis

Hepatitis is a common disorder with diverse etiology. Hepatitis can be classified as acute when duration is short and as chronic when it lasts more than 6 months. It can also be suspected to be chronic because of its cause. When evaluating a patient with hepatitis, investigation for viral etiologies is usually the first step, however it is important not to forget the other possibilities of drug- or chemical-related injury, as well as the multiple immune, metabolic and toxic causes of hepatitis. In this article, we have dedicated the larger part of our discussion to viral etiologies. There has been enormous progress over the past few years in the management of viral hepatitis, especially of viral hepatitis B and C. In this article, we discussed current therapeutic options in the management of these relatively common disorders and provided some recommendations in preventing transmission of these infections.

Prevalence of and risk factors for hepatitis C virus infection among STD clinic clientele in Miami, Florida

OBJECTIVES

Hepatitis C virus (HCV) is the most common chronic blood borne viral infection in the United States. We assessed the HCV prevalence, risk factors, and sensitivity of the Centers for Disease Control and Prevention's (CDC) routine screening criteria among clients of a large urban sexually transmitted disease (STD) clinic.

METHODS

Participants were recruited from a public STD clinic in Miami, Florida, and were interviewed regarding known and potential risk factors. The survey assessed CDC screening criteria, as well as other risk factors (for example, intranasal drug use, history of incarceration, exchanging sex for money, number of lifetime sex partners, and history of an STD). Testing was done by enzyme immunoassay (EIA) and confirmed by recombinant immunoblot assay (RIBA).

RESULTS

The prevalence of anti-HCV positivity was 4.7%. Four variables were significantly associated with being anti-HCV positive, independent of confounding factors. These included injection drug use (odds ratio (OR) = 31.6; 95% confidence intervals (CI) 11.0 to 90.5); history of incarceration (OR = 3.0; 95% CI 1.1 to 8.1); sexual contact with an HCV positive person (OR 12.7; 95% CI 2.5 to 64.7); and older age (OR 1.4; 95% CI 1.2, 1.6). The sensitivity of CDC's routine screening criteria was 69% and specificity was 91%.

CONCLUSIONS

The prevalence of anti-HCV in this clinic was similar to that determined in studies of comparable populations. Having sexual contact with an HCV positive person and history of incarceration were independently associated with being anti-HCV positive. CDC's screening criteria identified approximately two thirds of the anti-HCV positive participants.

Hepatitis C in the HIV-infected patient

Hepatitis C virus infection is common in people with HIV and represents an increasingly important public health problem. Thus, although there remains a considerable amount of uncertainty about whom to treat and the best way to treat, providers must use available information generated chiefly from patients without HIV to manage HCV infection in coinfected patients. Future efforts should include prospective studies that demonstrate the natural history and optimal management of HIV/HCV-coinfected patients, including the feasibility of liver transplantation.

Prevalence of illicit drug use in plasmapheresis donors

BACKGROUND AND OBJECTIVES

No data are presently available concerning the frequency of illicit drug use in plasmapheresis donors. We therefore examined source plasma units produced in the United States (US) and in Germany for evidence of illicit drug use among donors.

MATERIALS AND METHODS

Seventy-five US plasma units from 10 different US states and 75 German plasma units that had been analysed principally for their protein composition were screened for drugs. Determinations were made, using automated immunoassays, of the presence of cannabis, cocaine, amphetamine, methamphetamine, methylenedioxymethamphetamine (MDMA), methylenedioxyethylamphetamine (MDE) and opiates. Positive results were confirmed by gas chromatography-mass spectrometry.

RESULTS

Eleven US plasma units were found to be positive for cocaine (14.6%), whereas all German samples were cocaine negative (P = 0.0007). Fifteen US plasma units (20%) and one German unit (1.3%) were confirmed as positive for cannabis (P = 0.0003). Three out of 75 US plasma units were positive for both cannabis and cocaine. In none of the 150 samples were amphetamine, methamphetamine, MDMA, MDE or opiates detected.

CONCLUSIONS

Our results strongly suggest differences in cocaine and cannabis consumption between US and German plasmapheresis donors. If these results are confirmed by larger-scale studies, random drug screening (including cocaine) of donors should be implemented in order to reduce the number of drug-containing plasma units, especially in the USA.

Antiviral effect and virus-host interactions in response to alpha interferon, gamma interferon, poly(i)-poly(c), tumor necrosis factor alpha, and ribavirin in hepatitis C virus subgenomic replicons

The recently developed hepatitis C virus (HCV) subgenomic replicon system was utilized to evaluate the efficacy of several known antiviral agents. Cell lines that persistently maintained a genotype 1b replicon were selected. The replicon resident in each cell line had acquired adaptive mutations in the NS5A region that increased colony-forming efficiency, and some replicons had acquired NS3 mutations that alone did not enhance colony-forming efficiency but were synergistic with NS5A mutations. A replicon constructed from the infectious clone of the HCV-1 strain (genotype 1a) was not capable of inducing colony formation even after the introduction of adaptive mutations identified in the genotype 1b replicon. Alpha interferon (IFN-alpha), IFN-gamma, and ribavirin exhibited antiviral activity, while double-stranded RNA (dsRNA) and tumor necrosis factor alpha did not. Analysis of transcript levels for a series of genes stimulated by IFN (ISGs) or dsRNA following treatment with IFN-alpha, IFN-gamma, and dsRNA revealed that both IFNs increased ISG transcript levels, but that some aspect of the dsRNA response pathway was defective in Huh7 cells and replicon cell lines in comparison to primary chimpanzee and tamarin hepatocytes. The colony-forming efficiency of the replicon was reduced or eliminated following replication in the presence of ribavirin, implicating the induction of error-prone replication. The potential role of error-prone replication in the synergy observed between IFN-alpha and ribavirin in attaining sustained viral clearance is discussed. These studies reveal characteristics of Huh7 cells that may contribute to their unique capacity to support HCV RNA synthesis and demonstrate the utility of the replicon system for mechanistic studies on antiviral agents.

The epidemiology of hepatitis C virus infection

The prevalence of hepatitis C virus (HCV) infection varies in different populations, ranging from as low as 0.6% in volunteer blood donors to as high as 80% in injection drug users. The prevalence of HCV in a population can be predicted by risk factors associated with the transmission of infection. These risk factors include injection drug use, blood product transfusion, organ transplantation, hemodialysis, occupational injury, sexual transmission, and vertical transmission. We review the literature regarding the incidence and prevalence of HCV infection and the evidence supporting various modes of HCV transmission.

Incidence and clinical course of major depression in patients with chronic hepatitis type C undergoing interferon-alpha therapy: a prospective study

This study examined the incidence, clinical course and its risk factors for major depression in patients with chronic hepatitis type C undergoing interferon-alpha therapy. Ninety-nine subjects underwent the psychiatric interviews for diagnosis of major depressive episode according to the DSM-IV criteria before the start of interferon therapy, and once every 4 weeks during both the 24-week treatment period and 12 weeks after the end of therapy. Depressive symptoms were also evaluated using the Hamilton Rating Scale for Depression. Major depression occurred during interferon therapy in 23 patients (23.2%). In 73.9% of them depression occurred within 8 weeks after the start of therapy. Twenty-two patients with depression completed the therapy and 59.1% of them achieved remission by the end of therapy with a mean duration of 11.6 weeks. Although the other 40.9% were not in remission at the end of therapy, they achieved remission within 12 weeks thereafter. The only risk factor for depression was advanced age. Depression occurs frequently among patients with hepatitis type C undergoing interferon-alpha therapy. Such patients require careful observation, and psychiatrists should be sufficiently aware of this significant psychiatric complication of interferon therapy.

Prevalence of hepatitis C virus infection and risk factors in an incarcerated juvenile population: a pilot study

OBJECTIVE

Hepatitis C virus (HCV) infection is the leading cause of liver failure in adulthood. Although the prevalence of HCV is reportedly as high as 80% in incarcerated adult populations, little is known about the prevalence of HCV in incarcerated juvenile populations. The purpose of this study was to determine the prevalence of HCV and high-risk behaviors in a population of incarcerated youths.

METHODS

We conducted a cross-sectional prevalence study of HCV infection in youths who were admitted to a juvenile detention center between September 1999 and January 2001. Subjects were asked questions regarding behaviors that might put them at risk for acquiring HCV, and blood was drawn for HCV antibody testing. Qualitative HCV RNA testing was performed on antibody-positive subjects.

RESULTS

Seventy-four percent (n = 305) of youths consented to participate in the seroprevalence study. HCV risk behaviors were common in this population: sexual activity (70%), intravenous drug use (6%), intranasal drug use (32%), body piercing (53%), and tattoos (33%). Six study youths (2%) were HCV antibody positive; 4 of these subjects were also HCV RNA positive. HCV-positive status was significantly associated with history of intravenous drug use and having had a sexually transmitted disease. Only 17% of study participants could correctly identify behaviors that might put them at risk for HCV.

CONCLUSIONS

The prevalence of HCV in incarcerated youths is higher than in the general pediatric population but not yet at adult levels of prevalence. Given the high prevalence of risk factors in this population, future studies should address the need for targeted HCV screening and education of incarcerated youths regarding risks for HCV.

A comparison of the molecular clock of hepatitis C virus in the United States and Japan predicts that hepatocellular carcinoma incidence in the United States will increase over the next two decades

The prevalence of hepatitis C virus (HCV)-related hepatocellular carcinoma (HCC) is considerably lower in the U.S. than in Japan. To elucidate this difference, we determined the time origin of the HCV epidemic in each country by using molecularly clocked long-term serial samples obtained from HCV carriers of genotypes 1a and 1b. The molecular clock estimated that HCV genotype 1 first appeared in Japan in around 1882, whereas emergence in the U.S. was delayed until around 1910. In addition, by statistical analysis using coalescent theory, the major spread time for HCV infection in Japan occurred in the 1930s, whereas widespread dissemination of HCV in the U.S. occurred in the 1960s. These estimates of viral spread time are consistent with epidemiologic observations and predict that the burden of HCC in the U.S. will increase in the next two to three decades, possibly to equal that currently experienced in Japan.

Treatment of patients with hepatitis C and normal serum aminotransferase levels

Approximately 30% of patients with chronic hepatitis C have normal serum alanine aminotransferase (ALT) levels and another 40% have ALT levels that are less than twice the upper limit of the normal range. Most patients with normal ALT levels have mild degrees of inflammation with mild or no fibrosis, and the rate of disease progression is reduced compared with that in patients with elevated ALT levels. Some patients with normal ALT levels have advanced fibrosis and cirrhosis on liver biopsy. Treatment of patients with normal ALT levels with either interferon monotherapy or interferon/ribavirin combination therapy has shown sustained virological response (SVR) rates that are equivalent to those achieved for patients with elevated ALT levels. Thus, patients with chronic hepatitis C should not be excluded from therapy based on ALT levels alone. The decision to initiate therapy with interferon and ribavirin should be based on a combination of factors independent of ALT levels including amount of fibrosis on liver biopsy, hepatitis C virus (HCV) genotype and viral level, patient age and motivation, and co-morbid illness, and the presence of other complicating conditions.

Course and outcome of hepatitis C

The hepatitis C virus (HCV) is a small enveloped RNA virus belonging to the family flaviviridae and genus hepacivirus. The HCV RNA genome is 9,600 nucleotides in length and encodes a single polyprotein that is post-translationally cleaved into 10 polypeptides including t3 structural (C, E1, and E2) and multiple nonstructural proteins ([NS] NS2 to NS5). The NS proteins include enzymes necessary for protein processing (proteases) and viral replication (RNA polymerase). The virus replicates at a high rate in the liver and has marked sequence heterogeneity. There are 6 genotypes and more than 90 subtypes of HCV, the most common in the United States being 1a and 1b (approximately 75%), 2a and 2b (approximately 15%), and 3 (approximately 7%). Acute hepatitis C is marked by appearance of HCV RNA in serum within 1 to 2 weeks of exposure followed by serum alanine aminotransferase (ALT) elevations, and then symptoms and jaundice. Antibody to HCV (anti-HCV) tends to arise late. In acute resolving hepatitis, HCV RNA is cleared and serum ALT levels fall to normal. However, 55% to 85% of patients do not clear virus, but develop chronic hepatitis C. Chronic hepatitis C is often asymptomatic, but is usually associated with persistent or fluctuating elevations in ALT levels. The chronic sequelae of hepatitis C include progressive hepatic fibrosis, cirrhosis, and hepatocellular carcinoma. Extra-hepatic manifestations include sicca syndrome, cryoglobulinemia, glomerulonephritis, and porphyria cutanea tarda. Knowledge of the course and outcome of hepatitis C is important in developing approaches to management and therapy.

Prevention of spread of hepatitis C

Hepatitis C virus (HCV) is transmitted by percutaneous or permucosal exposure to infectious blood or blood-derived body fluids. Based on the results of cohort and acute case control studies, risk factors associated with acquiring HCV infection in the United States have included transfusion of blood and blood products and transplantation of solid organs from infected donors, injecting drug use, occupational exposure to blood (primarily contaminated needle sticks), birth to an infected mother, sex with an infected partner, and multiple heterosexual partners. Nosocomial and iatrogenic transmission of HCV primarily are recognized in the context of outbreaks, and primarily have resulted from unsafe injection practices. Transmission from HCV-infected health care workers to patients is rare. Transfusions and transplants have been virtually eliminated as sources for transmission, and most (68%) newly acquired cases of hepatitis C are related to injecting drug use. The primary prevention of illegal drug injecting will eliminate the greatest risk factor for HCV infection in the United States. Other prevention strategies that need to be widely implemented include risk reduction counseling and services and review and improvement of infection control practices in all types of health care settings. Testing for HCV infection should be routinely performed for persons at high risk for infection or who require postexposure management. There are no recommendations for routine restriction of professional activities for HCV-infected health care workers, and persons should not be excluded from work, school, play, and child care or other settings on the basis of their HCV infection status.