Simultaneous transmission of human immunodeficiency virus and hepatitis C virus from a needle-stick injury

Human immunodeficiency virus facilitates infection/replication of hepatitis C virus in native human macrophages

Hepatitis C virus (HCV) was found to replicate in monocytes/macrophages particularly in patients with human immunodeficiency virus type 1 (HIV-1) infection. This study was undertaken to determine whether HIV facilitates HCV infection of native human macrophages in vitro. Monocytes/macrophages were collected from healthy donors, infected with HIV M-tropic molecular clone, and then exposed to HCV-positive sera. Presence of positive and negative HCV RNA strands was determined with a novel strand-specific quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR). Preceding as well as near-simultaneous infection with HIV made the macrophages more susceptible to infection with HCV; in particular, an HCV RNA-negative strand was detectable almost exclusively in the setting of concomitant HIV infection. Furthermore, HCV RNA load correlated with HIV replication level in the early stage of infection. The ratio of positive to negative strand in macrophages was lower than in control liver samples. HIV infection was also found to facilitate HCV replication in a Daudi B-cell line with engineered CD4 expression. It seems that HIV infection can facilitate replication of HCV in monocytes/macrophages either by rendering cells more susceptible to HCV infection or by increasing HCV replication. This could explain the presence of extrahepatic HCV replication in HIV-coinfected individuals.

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.

Occupationally acquired human immunodeficiency virus (HIV) infection: national case surveillance data during 20 years of the HIV epidemic in the United States

OBJECTIVE

To characterize occupationally acquired human immunodeficiency virus (HIV) infection detected through case surveillance efforts in the United States.

DESIGN

National surveillance systems, based on voluntary case reporting.

SETTING

Healthcare or laboratory (clinical or research) settings.

PATIENTS

Healthcare workers, defined as individuals employed in healthcare or laboratory settings (including students and trainees), who are infected with HIV.

METHODS

Review of data reported through December 2001 in the HIV/AIDS Reporting System and the National Surveillance for Occupationally Acquired HIV Infection.

RESULTS

Of 57 healthcare workers with documented occupationally acquired HIV infection, most (86%) were exposed to blood, and most (88%) had percutaneous injuries. The circumstances varied among 51 percutaneous injuries, with the largest proportion (41%) occurring after a procedure, 35% occurring during a procedure, and 20% occurring during disposal of sharp objects. Unexpected circumstances difficult to anticipate during or after procedures accounted for 20% of all injuries. Of 55 known source patients, most (69%) had acquired immunodeficiency syndrome (AIDS) at the time of occupational exposure, but some (11%) had asymptomatic HIV infection. Eight (14%) of the healthcare workers were infected despite receiving postexposure prophylaxis (PEP).

CONCLUSIONS

Prevention strategies for occupationally acquired HIV infection should continue to emphasize avoiding blood exposures. Healthcare workers should be educated about both the benefits and the limitations of PEP, which does not always prevent HIV infection following an exposure. Technologic advances (eg, safety-engineered devices) may further enhance safety in the healthcare workplace.

A patient with primary human immunodeficiency virus infection for whom highly active antiretroviral therapy was successful

We report the case of a 25-year-old male Japanese homosexual with primary human immunodeficiency virus (HIV)-1 infection and early stage syphilis. Approximately 60 days after HIV exposure by sex with another man, the patient abruptly had high fever, after which he experienced a variety of severe, prolonged symptoms such as painful oral mucosa ulcerations, rash, lymphadenopathy, splenomegaly, and a 5.5-kg weight loss. Serum lactate dehydrogenase and liver biochemical test values were elevated. Antibodies to HIV by both enzyme-linked immunosorbent assay (ELISA) and Western blot (WB) test were negative at the time of symptom onset, but serum HIV-1 RNA level was 1 585 000 copies/ml. Antibody seroconversions were found on day 9 after the onset of symptoms by ELISA and on day 16 by WB test, suggesting primary HIV infection. Within 2 weeks of starting highly active antiretroviral therapy (HAART), all symptoms except lymphadenopathy were resolved, and the serum HIV-1 RNA level dramatically decreased to 5011 copies/ml, eventually becoming undetectable by the standard method. The patient has remained asymptomatic for the 18 months since symptom resolution after HAART, and HIV-1 RNA remains undetectable.

HIV and AIDS in the workplace

Since the onset of the HIV epidemic, AIDS and HIV infection have presented tremendous challenges to infected individuals seeking to remain productive in the workplace, to employers coping with the special needs of such individuals, and to physicians who treat and counsel exposed or infected personnel. OEM physicians should strive to ensure that employers are familiar with legislation and guidelines protecting the rights of infected employees, and they should support rational workplace policies applying to employees with HIV infection or AIDS. When the potential for occupational HIV exposure exists, OEM physicians should ensure that adequate training around exposure prevention, triage, and treatment is provided. OEM physicians who treat individuals with occupational HIV exposures should involve themselves in institutional efforts to prevent exposures through the use of safer devices and procedures, and they should ensure that immediate and adequate clinical evaluation of exposures is available at all times.

Infectious hepatitis C, hepatitis G, and TT virus: review and implications for dentists

In the past 10 years, hepatitis C and G viruses have been identified, and in the last two years a further parenterally transmitted agent, termed TT virus (TTV), has been discovered. These viruses have a worldwide distribution and frequently cause chronic infection. The purpose of this article was to promote an understanding of these viral agents and their relevance in dental practice. Infected patients may develop a chronic carrier state without clinical disease or may develop liver disease, and may have related oral conditions. Dental providers will see a growing number of patients with HCV/HGV and possibly TTV infection. All of these patients require appropriate infection control measures during dental treatment.

Rapidly progressive fibrosing cholestatic hepatitis--hepatitis C virus in HIV coinfection

Fibrosing cholestatic hepatitis (FCH) is a severe and progressive form of liver dysfunction seen in organ transplant recipients infected with hepatitis B virus or hepatitis C virus (HCV) and has been attributed to cytopathic liver injury. To date, no case of FCH due to HCV has been reported in HIV-positive individuals. We describe two cases of HCV-induced FCH in two patients coinfected with HIV, culminating in rapidly progressive liver failure and death. Histological features and progression in both cases were not consistent with drug effect or obstruction. Late institution of interferon-based therapy was ultimately unsuccessful. The HCV RNA was not markedly elevated in these cases, suggesting that the cytopathic effect of HCV in these patients was not simply a consequence of viral load. FCH may in part explain the accelerated development of cirrhosis previously observed among coinfected patients. Clinicians should remain vigilant for FCH in the HIV/HCV population and consider antiviral treatment in this setting.

Hepatitis C and human immune deficiency coinfection at the era of highly active antiretroviral therapy

Interactions between human immunodeficiency virus (HIV) and hepatitis C virus (HCV) have been widely studied before the introduction of highly active antiretroviral therapies (HAART). We reviewed the potential impact of HAART on hepatitis C as well as the interactions between HIV and HCV therapies. Physicians should be aware of the potential risk of: (i) symptomatic liver disease in HCV-HIV-coinfected patients at the era of triple antiretroviral therapy; (ii) potential liver deterioration paralleling immune restoration; (iii) lack of impact of triple antiretroviral therapy on HCV load; and (iv) potential drug-related hepatitis which may modify the natural history of HCV-related liver disease. Liver biopsies should be performed regularly in these patients in order to identify patients with severe liver disease who require early initiation of anti-HCV therapy under close monitoring of their immune status. Treatment is, to date, based on the combination of ribavirin and interferon with an expected sustained response rate around 25%. An important unresolved issue is to better delineate the temporal place of anti-HCV and anti-HIV antiviral therapies. At least in coinfected patients with significant liver disease, namely necro-inflammatory activity and/or fibrosis >or= 2, we believe that anti-HCV therapy is the priority since it lessens the risk of drug-induced hepatitis and of hepatitis due to immune restoration.

Hepatitis C. Epidemiologic quandaries

Although many aspects of the transmission of HCV have been clarified, some important issues remain controversial, and the conventional wisdom may be based more on opinion than data (Table 2). HCV is transmitted by percutaneous exposure to contaminated blood, uncommonly from a mother to her infant and between sexual partners, and rarely during the provision of medical care in developed nations. Improved behavioral research instruments are needed to further the understanding of the practices that actually transmit infection. In addition, large, prospective studies are necessary to characterize the frequency [table: see text] of transmission between sexual partners and the potential role of cesarian section in reducing HCV transmission to infants.

Lack of seroconversion in a health care worker after polymerase chain reaction-documented acute hepatitis C resulting from a needlestick injury

We present a case of documented acute hepatitis C that occurred in a health care worker who sustained a needlestick injury while caring for an individual who was infected with both hepatitis C virus (HCV) and human immunodeficiency virus (HIV). According to the findings of third-generation serological assays performed during a follow-up of >1 year, the health care worker, who was treated with interferon-alpha (during weeks 2-6) and ribavirin (during weeks 5-9), did not develop antibodies against HCV, in spite of documentation of an HCV-specific T cell response.

Preventing needlesticks in emergency medical system workers

Emergency medical system (EMS) workers frequently use sharp devices in injury-prone circumstances that involve limited visibility, confined spaces, rapidly moving vehicles, and uncooperative victims. This study examined the efficacy of an automatic self-retracting lancet in reducing needlestick injuries and related direct and indirect costs. Subjects were 477 active-duty EMS workers. Counseling, laboratory testing (hepatitis B and C, hepatic function enzymes, and human immunodeficiency virus), antiviral prophylaxis, and immunizations were provided according to US Public Health Service guidelines. Baseline and biennial laboratory testing for hepatitis B and C and liver function enzymes were conducted. After the introduction of a spring-loaded automatic-retracting type glucometer lancet device, needlestick injuries decreased from 16 per 954 EMS worker-years to 2 per 477 EMS worker-years. The annualized cost of treatment declined from $8276 to $2068. The change to a self-retracting device decreased the number of needlestick injuries and was cost-effective with a minimal increase in device cost (annualized $366 per year).

Occupational transmission of human immunodeficiency virus and hepatitis C virus after a punch

Although the simultaneous transmission of either human immunodeficiency virus (HIV) and hepatitis C virus or HIV and hepatitis B virus from a single source has already been described, this is the first case of transmission to occur after a blow with the fist.

Antiretroviral prophylaxis of health care workers at two urban medical centers

We examined the influence of job category, source patient HIV status, and exposure type as predictors of whether health care workers initiated antiretroviral prophylaxis after potential blood-borne pathogen exposures. Of 639 exposures over an 18-month period, 82 individuals (13%) elected to receive prophylaxis, of whom 66% took medications for fewer than 96 hours and 12% completed a 4-week course. Reasons for early drug discontinuation included confirmation of source patient HIV-negative serological status (65%), gastrointestinal side effects (13%), headache (4%), and personal decision after counseling/other input (18%). Individuals exposed to HIV-positive source patients were more likely to initiate prophylaxis (odds ratio [OR], 5.1; 95% confidence interval [CI] 2.6 to 9.9). Licensed nurses were less likely than others to accept prophylaxis (OR, 0.5; 95% CI, 0.3 to 0.8), whereas physicians and medical students were more likely to accept prophylaxis (OR, 1.9; 95% CI, 1.1 to 3.3).

Diagnosis of primary HIV-1 infection and duration of follow-up after HIV exposure. Karolinska Institute Primary HIV Infection Study Group

OBJECTIVE

To determine the sensitivity of 33 currently available and seven earlier tests for the detection of HIV or HIV antibody in primary HIV-1 infection, to estimate the duration of the 'window period' and the influence of early initiated antiretroviral treatment (ART).

DESIGN

A prospective cohort study of 38 patients with primary HIV-1 infection. ART was initiated at a median time of 13 (range 0-23) days after the onset of symptoms in 10 patients.

MAIN OUTCOME MEASURES

The time from infection to onset of symptoms and from onset of symptoms to the appearance of HIV antibody as measured by 36 different tests, and the start and duration of viraemia, as detected by four different tests.

RESULTS

The illness appeared 13-15 days after infection in 12 of 15 determinable cases, and seroconversion was detected within 1-2 weeks after the onset of illness by 27 of 30 currently available tests for HIV antibody, in contrast to the 2-7 weeks or more needed by the old tests. HIV RNA appeared during the week preceding the onset of illness and was detected in all subsequent samples, except when ART had been initiated, which also induced a delay of the antibody response.

CONCLUSION

Many tests for HIV or HIV antibody can now be employed for an early confirmation of primary HIV infection (PHI). Currently available screening tests proved much more sensitive than older tests, and seroconversion was usually detected within one month after infection. Consequently, in Sweden we now recommend only 3 months of follow-up after most cases of HIV exposure.

Efficacy of postexposure prophylaxis after intravaginal exposure of pig-tailed macaques to a human-derived retrovirus (human immunodeficiency virus type 2)

Postexposure prophylaxis (PEP) after intravaginal exposure to human immunodeficiency virus (HIV) was investigated using the HIV type 2 (HIV-2)/pig-tailed macaque transmission model. PEP for 28 days with the reverse transcriptase inhibitor (R)-9-(2-phosphonylmethoxypropyl)adenine (PMPA; tenofovir) was initiated 12 to 72 h following HIV-2 exposure. Systemic infection was not evident in the 12- and 36-h groups, as defined by plasma viremia, cell-associated provirus, antibody responses, and lymph node virus. Breakthrough infection in the 72-h group was detected at week 16 post-virus exposure. These results demonstrate for the first time using a vaginal transmission model that early intervention after high-risk sexual exposures may prevent infection.

[Use of individual protection equipment among nursing workers injured by puncture-cutting tools]

The present study analyzed work related accidents involving nursing personnel from a public hospital in the state of São Paulo. The study population comprised the entire nursing staff. The results obtained showed a high incidence of accidents with puncture-cutting instruments, particularly among the auxilliary nursing staff, which indicates that these workers don't often use individual protection equipment, even when it is made available at the work place. Due to the manipulation of sharp instruments, nursing personnel are especially vulnerable to suffer biological risks and serious diseases. These results indicate the need to prevent the occurrence of such accidents.

Occupational exposure to blood: search for a relation between personality and behavior

OBJECTIVE

To describe the behavior of French nurses after occupational exposure to blood (OEB); to study the reasons for not reporting an OEB to the occupational medicine service or the hospital authorities, and to explore the links between personality traits and both the risk of having an OEB and the likelihood of reporting it.

DESIGN

A descriptive and correlational study using a cross-sectional survey for data collection.

SETTING

Six nursing schools (four initial training institutes and two specialty training schools, one for surgical nurses and one for nurse anesthetists) and six hospitals in Lorraine.

PARTICIPANTS

942 nurses and 459 nursing students were approached, and 964 (69%) replied to the questionnaire.

METHODS

The participants received an anonymous two-part questionnaire. The first part explored the knowledge of the risk and Standard Precautions and collected details of the history of OEB. Reporting of OEB to the occupational medicine service or the hospital authorities and the nature of serological monitoring after OEB also were explored. The second part was composed of the Zuckerman sensation-seeking scale, exploring four areas: disinhibition, danger- and adventure-seeking, seeking new experiences, and susceptibility to boredom.

RESULTS

947 nurses were vaccinated against hepatitis B, but only 528 (56%) had checked that they were effectively immunized. Only 166 respondents (17%) stated they routinely used gloves during all procedures in which they were exposed to blood. There were 505 recorded OEB during the study period (0.24 per person per year). The most frequently reported OEB were those involving hollow needles (57%). Approximately one half (48.5%) of all OEB were reported. "Good local antisepsis immediately after the accident" was the reason most often given to justify nonreporting. Only 57% of OEB victims sought to determine the serological status of the source patient for human immunodeficiency virus (HIV), hepatitis C virus (HCV), and hepatitis B virus immediately after accident. Only 40% and 31% of OEB victims checked their own HIV and HCV serostatus 3 and 6 months after OEB, respectively. Few staff adopted safer-sex measures after OEB, and some continued to donate blood in subsequent months. Logistic regression identified two variables significantly and independently linked to the risk of having at least one OEB in the 27 months preceding the date on which the questionnaire was completed: having a permanent position and having a higher degree of disinhibition. Taking into account the number of OEB during this period (Poisson regression), four variables were significantly and independently linked to the risk of having a larger number of OEB: having a permanent position; having a higher degree of disinhibition; being more susceptible to boredom; and having less nursing experience. In logistic regression, three variables emerged as being significantly and independently linked to reporting all OEB: younger age; having had at least one percutaneous injury (excluding splashes); and having lower susceptibility to boredom.

CONCLUSION

Nursing personnel continue to ignore or be unaware of many factors surrounding OEB, meaning that information and counseling must continue unabated. Knowledge of the risk, of the benefit of respecting Standard Precautions, and of the importance of notification and serological follow-up is still inadequate. Finally, certain personality traits, such as a high level of disinhibition and susceptibility to boredom, appear to be linked to the risk of OEB. Subjects strongly susceptible to boredom are less likely to report such accidents.

Risk and management of blood-borne infections in health care workers

Exposure to blood-borne pathogens poses a serious risk to health care workers (HCWs). We review the risk and management of human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) infections in HCWs and also discuss current methods for preventing exposures and recommendations for postexposure prophylaxis. In the health care setting, blood-borne pathogen transmission occurs predominantly by percutaneous or mucosal exposure of workers to the blood or body fluids of infected patients. Prospective studies of HCWs have estimated that the average risk for HIV transmission after a percutaneous exposure is approximately 0.3%, the risk of HBV transmission is 6 to 30%, and the risk of HCV transmission is approximately 1.8%. To minimize the risk of blood-borne pathogen transmission from HCWs to patients, all HCWs should adhere to standard precautions, including the appropriate use of hand washing, protective barriers, and care in the use and disposal of needles and other sharp instruments. Employers should have in place a system that includes written protocols for prompt reporting, evaluation, counseling, treatment, and follow-up of occupational exposures that may place a worker at risk of blood-borne pathogen infection. A sustained commitment to the occupational health of all HCWs will ensure maximum protection for HCWs and patients and the availability of optimal medical care for all who need it.

Risk and management of blood-borne infections in health care workers

Exposure to blood-borne pathogens poses a serious risk to health care workers (HCWs). We review the risk and management of human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) infections in HCWs and also discuss current methods for preventing exposures and recommendations for postexposure prophylaxis. In the health care setting, blood-borne pathogen transmission occurs predominantly by percutaneous or mucosal exposure of workers to the blood or body fluids of infected patients. Prospective studies of HCWs have estimated that the average risk for HIV transmission after a percutaneous exposure is approximately 0.3%, the risk of HBV transmission is 6 to 30%, and the risk of HCV transmission is approximately 1.8%. To minimize the risk of blood-borne pathogen transmission from HCWs to patients, all HCWs should adhere to standard precautions, including the appropriate use of hand washing, protective barriers, and care in the use and disposal of needles and other sharp instruments. Employers should have in place a system that includes written protocols for prompt reporting, evaluation, counseling, treatment, and follow-up of occupational exposures that may place a worker at risk of blood-borne pathogen infection. A sustained commitment to the occupational health of all HCWs will ensure maximum protection for HCWs and patients and the availability of optimal medical care for all who need it.

Emergency department management of blood and body fluid exposures

Exposure to blood and body fluids that may be contaminated with infectious agents is a common occupational hazard for health care workers. Health care workers in the emergency department or out-of-hospital setting are at especially high risk for exposure to blood or body fluids. Nonemergency health care workers are frequently referred to hospital EDs for immediate treatment of occupation exposures. A series of recommendations by the Centers for Disease Control and Prevention evolved over the past decade, and changes are expected to continue. This state-of the-art article reviews current recommendations for management of persons exposed to blood or body fluids and discusses the scientific basis for recommendations regarding hepatitis B virus, hepatitis C virus, and HIV.

Hepatitis C epidemiology

Hepatitis C virus infection occurs in all parts of the world. Infection is generally due to percutaneous exposures, though sexual and perinatal transmission may occur. While further study is needed to elucidate the biology of HCV transmission and develop vaccines for prevention, new HCV infections can be reduced by economic development and education regarding blood-borne infections.

Liver fibrosis progression in human immunodeficiency virus and hepatitis C virus coinfected patients. The Multivirc Group

The natural history of hepatitis C virus (HCV) infection in human immunodeficiency virus (HIV)-infected patients has never been studied according to the concept of liver fibrosis progression. The aim of this work was to assess the fibrosis progression rate in HIV-HCV coinfected patients and in patients infected by HCV only. A cohort of 122 HIV-HCV coinfected patients was compared with a control group of 122 HIV-negative HCV-infected patients. Groups were matched according to age, sex, daily alcohol consumption, age at HCV infection, and duration and route of HCV infection. The fibrosis progression rate was defined as the ratio between fibrosis stage (METAVIR scoring system) and the HCV duration. The prevalence of extensive liver fibrosis (METAVIR fibrosis scores 2, 3, and 4) and moderate or severe activity were higher in HIV-infected patients (60% and 54%, respectively) than in control patients (47% and 30%, respectively; P <.05 and P <.001, respectively). The median fibrosis progression rate in coinfected patients and in control patients was 0.153 (95% confidence interval [CI], 0.117-0.181) and 0.106 (95% CI, 0.084-0.125) fibrosis units per year, respectively (P <.0001). HIV seropositivity (P <.0001), alcohol consumption (>50 g/d, P =.0002), age at HCV infection (<25 years old, P <.0001), and severe immunosuppression (CD4 count 50 g/d), CD4 count ( Collapse

Key Words Collapse

MESH Headings

• Adult
• Alcohol Drinking
• Cohort Studies
• Disease Progression
• Female
• HIV Infections/complications
• HIV Infections/therapy
• HIV Seronegativity
• Hepatitis C/complications
• Hepatitis C/virology
• Humans
• Immunosuppression Therapy
• Liver Cirrhosis/physiopathology
• Liver Cirrhosis/virology
• Male
• Prospective Studies
• Retrospective Studies
• Risk Factors
• Time Factors

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Grants Collapse

Affiliation(s)

Y Benhamou Service d'Hépato-Gastroentérologie, Groupe Hospitalier Pitié Salpêtrière and UPRES-A 8067, Paris, France.
M Bochet
V Di Martino
F Charlotte
F Azria
A Coutellier
M Vidaud
F Bricaire
P Opolon
C Katlama
T Poynard

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Hepatitis C: the lurking dragon

Hepatitis C virus (HCV) is the most common chronic blood-borne infection in the United States. An estimated 3.9 million Americans (1.4%) are infected with HCV. The 10th leading cause of death in U.S. adults is chronic liver disease (CLD), which accounts for 25,000 deaths annually. Approximately 40% of all CLD is related to HCV, causing 8000 to 10,000 deaths annually. In addition, approximately 60% of people with HIV are believed to be coinfected with HCV, which hastens their progression to AIDS.

Hepatitis viruses A, B, C, D, E and G: implications for dental personnel

BACKGROUND

This article provides dental personnel with a brief overview of the different types of viral hepatitis, including their epidemiology, clinical features, prevention and treatment. It also explores the ramifications of these diseases for the practice of dentistry. DESCRIPTION OF THE CONDITION: Viral hepatitis is an inflammation of the liver caused by one of at least six distinct viruses. The hepatitis A and E viruses, or HAV and HEV, are enterically transmitted viruses that produce acute disease only. The hepatitis B, C and D viruses, or HBV, HCV and HDV, are most efficiently transmitted by infected blood, but also can be transmitted by exposure to other infectious bodily fluids. These three viruses can cause acute or chronic hepatitis. People with chronic viral hepatitis can develop chronic liver disease, cirrhosis and hepatocellular carcinoma. The hepatitis G virus was recently identified, and its ability to cause clinically significant acute or chronic hepatitis is unknown.

CONCLUSIONS

Dental health care workers, or DHCWs, should be concerned primarily with HBV, HCV and HDV, as occupational exposure to these pathogens places them at risk of developing acute or chronic infections. Vaccines and immune globulins are available and effective in protecting against infections with HAV, HBV and HDV, but not HCV.

CLINICAL IMPLICATIONS

DHCWs should become knowledgeable about viral hepatitis. They should be vaccinated against hepatitis B. Adherence to infection control measures will help prevent occupational transmission of all bloodborne pathogens, including hepatitis viruses.

Human immunodeficiency virus infection, Part II

The acceptance of highly active antiretroviral therapy (HAART) among patients and health care providers has had a dramatic impact on the epidemiology and clinical characteristics of many opportunistic infections associated with human immunodeficiency virus (HIV). Previously intractable opportunistic infections and syndromes are now far less common. In addition, effective antibiotic prophylactic therapies have had a profound impact on the risk of patients developing particular infections and on the incidence of these infections overall. Most notable among these are Pneumocystis carinii, disseminated Mycobacterium avium complex, tuberculosis, and toxoplasmosis. Nevertheless, infections continue to cause significant morbidity and mortality among patients who are infected with HIV. The role of HAART in many clinical situations is unquestioned. Compelling data from clinical trials support the use of these therapies during pregnancy to prevent perinatal transmission of HIV. HAART is also recommended for health care workers who have had a "significant" exposure to the blood of an HIV-infected patient. Both of these situations are discussed in detail in this article. In addition, although more controversial, increasing evidence supports the use of HAART during the acute HIV seroconversion syndrome. An "immune reconstitution syndrome" has been newly described for patients in the early phases of treatment with HAART who develop tuberculosis, M avium complex, and cytomegalovirus disease. Accumulating data support the use of hydroxyurea, an agent with a long history in the field of myeloproliferative disorders, for the treatment of HIV. Newer agents, particularly abacavir and adefovir dipivoxil, are available through expanded access protocols, and their roles are being defined and clarified.

[Interactions between the human immunodeficiency virus and hepatitis C virus]

INTRODUCTION

Prevalence of hepatitis C virus (HCV) infection in human immunodeficiency virus (HIV)-infected subjects is around 9%, varying according to the mode of contamination. Reciprocal interactions between the two viruses have to be evaluated.

CURRENT KNOWLEDGE AND KEY POINTS

HCV infection is usually associated with chronic hepatitis and detectable viremia in HIV-infected patients. HIV infection enhances HCV replication, leading to more severe liver lesions and to a more rapid occurrence of cirrhosis. This underlines the need for both early diagnosis and therapy in order to avoid severe evolution of the liver disease.

FUTURE PROSPECTS AND PROJECTS

Even though the rate of long-term responses to interferon alpha is low, improvement may be expected from combined therapies, especially with combination including ribavirin. The impact of both antiretroviral triple therapy and accompanying immune restoration on natural history and treatment of HCV infection has to be assessed, as the above mentioned consensual conclusions may be modified in a near future.

Occupational exposure to human immunodeficiency virus: what healthcare providers should know

PURPOSE

The author reviews the risks of occupational exposure to HIV and provides a rationale for new postexposure guidelines for healthcare workers.

OVERVIEW

Approximately 50,000 percutaneous exposures occur yearly among healthcare workers in the United States. Of these, approximately 5000 involve exposures to blood that is known to be infected with HIV. The risk of transmission after percutaneous exposure to HIV-tainted blood has been estimated to be 0.3%, but the risk may be considerably higher to the healthcare worker if any of the following is present: a deep injury; visible blood on the sharp device; a procedure that involves a needle placed in the patient's artery or vein; and a patient with advanced AIDS. The increasing resistance of HIV strains to antiretroviral therapy continues to make treatment more difficult.

CLINICAL IMPLICATIONS

Postexposure prophylaxis with zidovudine may reduce the risk of occupational infection by 80%. Advances in the ability to ameliorate HIV transmission rates and to treat individuals with resistant disease through innovations in drug therapy, engineering of controls for injury prevention, and more focused postexposure evaluation offer the hope of reducing this infrequent, but dangerous, occupational threat.

Sexual transmission of hepatitis C virus and prevention with intramuscular immunoglobulin

The sexual transmission of hepatitis C virus (HCV) has long been debated. The prevalence of infected at-risk partners varies from 0% to 30%. In a prospective study, the risk of infection was quantified in steady heterosexual partners and the prophylactic effect of normal human polyvalent immune serum globulin (ISG) was evaluated. A total of 899 at-risk partners of HCV-infected patients were enrolled in a single-blind randomized controlled trial and assigned to receive every 2 month 4 mL of intramuscular ISG from unscreened donors (450 partners) or placebo (499 partners). Seven partners developed acute HCV infection (increased aminotransferase levels and appearance of HCV-RNA): six of the placebo group (incidence density [ID] 12.00/1,000 person year; 95% confidence interval [CI] 3.0 to 21.61), and only one of the ISG-treated group (ID 1.98/1,000 person year; 95% CI 0 to 5.86). The risk of infection was significantly higher in controls versus treated individuals (p = 0.03). Six couples had genotype 1b (85%), and one couple had genotype 1a; HCV sequence homology strongly supported sexual transmission. Our trial demonstrates that HCV infection can be sexually transmitted and quantifies the risk of sexual transmission: for every year of at-risk sexual relationship, almost 1% of the partners became infected. Intramuscular ISG is safe and well tolerated. Unlike ISG from screened donors, ISG from donors unscreened for anti-HCV contains high titers of anti-gpE1/gpE2 neutralizing antibodies and high neutralizing activity. Anti-HCV hyperimmune globulin could be prepared from anti-HCV-positive blood units and could be used to protect sexual partners and in other at-risk situations of exposure to HCV infection.

Postmortem blood tests for HIV, HBV, and HCV in a body donation program

A retrospective analysis of the results of blood tests conducted on body donors received by the Anatomical Gift Registry of the Medical College of Wisconsin (MCW) was performed. Over the 5-year period from April 1992 through March 1997 a total of 785 body donors were tested for Human Immunodeficiency Virus (HIV) and Hepatitis B and C Viruses (HBV and HCV). Eighteen of the 785 donors (2.3%) tested positive for one of these infectious agents. Two donors were positive for HIV, six were positive for HBV and ten were positive for HCV. The death certificates and files of those donors who tested positive were reviewed and the results are presented here. Blood testing prior to the use of the body donors is an effective and reasonable way of identifying the presence of these infectious agents, thus reducing the risk to those who work with cadavers. The cost for the testing at MCW is about $60 per donor.

Hepatitis C virus infection: Review and implications for the dentist

OBJECTIVE

The purpose of this report was to review the current literature on hepatitis C virus infection, with particular attention to the aspects of interest for dental health care staff.

MATERIAL AND METHODS

The authors searched original research and review articles on specific aspects of hepatitis C virus infection, including articles on virology, epidemiology, transmission, diagnosis, natural history, extrahepatic manifestations, therapy and oral aspects of hepatitis C virus infection. The relevant material was evaluated and reviewed.

RESULTS

Hepatitis C virus is an RNA virus that is present throughout the world and has major geographic variations. The virus, transmitted mainly by means of blood contact, causes chronic hepatitis in up to 80% of cases and may give rise to hepatic cirrhosis and hepatocellular carcinoma in a significant proportion of patients. Although it is of limited efficacy, interferon alpha is currently the drug of choice in the treatment of the infection. Hepatitis C virus infection is associated with a number of extrahepatic manifestations that may include oral diseases such as lichen planus or sialadenitis. Although there are documented cases of nosocomial transmission to health care workers after percutaneous exposure, the prevalence of hepatitis C virus among dental staff members is probably similar to that in the general population.

CONCLUSION

Hepatitis C virus infection is a relatively common infection worldwide (1.4% in the US general population) that causes significant chronic hepatic disease. The dentist is thus likely to face a growing number of patients with a diagnosis of hepatitis C virus infection. For this reason it is essential for dental health care workers to be aware of the principal features of the disease and of its oral and dental implications.

Retrospective analysis of the impact of HIV infection and alcohol use on chronic hepatitis C in a large cohort of drug users

BACKGROUND/AIM

This retrospective study aimed to better define the respective biological and pathological impact of human immunodeficiency virus infection and chronic alcohol consumption on the course of hepatitis C virus infection in intravenous drug users.

METHODS

Two hundred and ten consecutive anti-HCV positive intravenous drug users, among whom 60 were also anti-HIV positive, took part in the study at the University Hospital, Paris, France.

RESULTS

The activity of aspartate aminotransferase and gamma-glutamyl transpeptidase was significantly increased in serum from anti-HIV positive patients. The mean hepatitis activity index was significantly higher in anti-HIV positive patients (p<0.05), among whom there was also a higher proportion of patients with cirrhosis as compared to anti-HIV negative patients (30.0 vs 15.3%, p<0.0001). Excessive alcohol drinking (recorded in around 35% of the patients, whatever their HIV status), as compared to non-excessive drinking, was more often associated with cirrhosis in anti-HIV negative (24.5 vs 11.3%, p<0.05) than in anti-HIV positive patients (30.4 vs 29.7%, not significant). In a multivariate analysis, HIV infection (relative risk 2.2, confidence interval 1.1-4.5) and excessive alcohol drinking (relative risk 1.9, confidence interval 1.0-3.9) were the variables independently associated with the risk of cirrhosis.

CONCLUSION

Human immunodeficiency virus infection worsens the course of chronic hepatitis C in intravenous drug users. Excessive alcohol drinking also appears to be a crucial negative cofactor, and therefore alcohol withdrawal should be proposed as an integral part of the therapy.

Hepatitis viruses: genetic variants and clinical significance

Variants of hepatitis B, C, and delta virus have been identified in patients both with acute and chronic infections. In the hepatitis B virus genome, naturally occurring mutations have been found in all viral genes, most notably in the genes coding for the structural envelope and nucleocapsid proteins. In the hepatitis C virus genome, the regions coding for the structural envelope proteins E1 and E2, as well as the 3'-contiguous non-structural region NS1, were found to be hypervariable. Viral variants may be associated with a specific clinical course of the infection, e.g., acute, fulminant or chronic hepatitis. Specific mutations may reduce viral clearance by immune mechanisms ('vaccine escape' and 'immune escape'), response to antiviral therapy ('therapy escape'), as well as detection ('diagnosis escape'). The exact contribution, however, of specific mutations to the pathogenesis and natural course of hepatitis B, C, or delta virus infection, including hepatocellular carcinoma development, and the response to antiviral treatment remains to be established.

Duration of time between exposure and seroconversion in healthcare workers with occupationally acquired infection with human immunodeficiency virus

Through December 1994, 41 healthcare workers with a documented seroconversion to human immunodeficiency virus (HIV) in temporal association to an occupational exposure were reported to the Centers for Disease Control and Prevention (CDC). Each tested positive for HIV antibodies within 12 months of the occupational exposure. Two (5%) of the 41 tested negative for HIV antibodies >6 months following the occupational exposure but were seropositive within 12 months of the injury. Both denied any subsequent exposures to HIV after the initial exposure, and in one case genetic sequencing confirmed the source of the infection. Four of the healthcare workers took postexposure zidovudine prophylaxis; each reported an acute retroviral syndrome within 6 weeks of their exposure, and each of the four seroconverted to HIV within 6 months of the exposure. Our data suggest that zidovudine prophylaxis does not delay the development of HIV antibodies beyond 6 months. Because many of the healthcare workers had follow-up testing at irregular intervals, with long periods between tests, it was not possible to define precisely when seroconversion occurred. However, our findings are compatible with previously published estimates that 95% of infected persons will develop HIV antibodies within 6 months of infection.