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Biomedical subjects

M J Alter

Publications and source records attributed to M J Alter.

At least 73 records · Page 4Linked to original sources
PubMed1993

Risk factors for hepatitis C virus infection among health care personnel in a community hospital.

OBJECTIVE: To determine the prevalence of and risk factors for antibody to the hepatitis C virus in hospital employees. METHODS: Retrospective testing of serum samples obtained from 1677 hospital employees during a prehepatitis B vaccination program in a private teaching community hospital. RESULTS: Twenty-three employees (1.4%) were found to have antibody to hepatitis C virus. The prevalence of antibody to hepatitis C virus was higher in blacks (3.4%) than in whites (1.1%, p = 0.03) and Hispanics (2.6%, p = 0.88). In a logistic regression model, factors significantly associated with antibody to hepatitis C virus seropositivity included antibody to hepatitis B core antigen (p = 0.002), a history of blood transfusion (p = 0.03), and needlestick injuries (p = 0.04). CONCLUSION: Although the prevalence of antibody to hepatitis C virus in health care workers was not high, needlestick injuries were associated with an increased risk for acquiring hepatitis C virus infection.

California↗
PubMed1993

Multicenter study of hepatitis C virus infection in chronic hemodialysis patients and hemodialysis center staff members.

Between April 1990 and December 1991, 499 (65%) of 767 patients and 142 (59%) of 239 staff members from 11 chronic hemodialysis centers in different geographic regions of the United States participated in a multicenter prospective cohort study that determined the prevalence and incidence of antibody to hepatitis C virus (anti-HCV) and evaluated their risk factors for HCV infection. Serum samples were tested for anti-HCV by enzyme immunoassay and HCV neutralization assay at baseline and 9 and 18 months later. Collected data included patient and staff demographics, number of years a patient had been on dialysis or staff were employed in the dialysis field, history and dates of blood transfusions, history of injecting drugs, and history of non-A, non-B hepatitis. Anti-HCV was detected in 52 (10%) of 499 patients and in two (1%) of 142 staff members. Logistic regression analysis revealed that in patients, an anti-HCV-positive test was associated with length of time on dialysis (3 or more years), history of injecting drugs, and history of non-A, non-B hepatitis. Anti-HCV positivity was not associated with history of blood transfusions, race, gender, or age. In patients, the cumulative incidence of HCV infection over an 18-month period was 4.6%. Throughout the 18-month follow-up period, no staff members became anti-HCV positive. The association between anti-HCV positivity and increasing patient years on dialysis may reflect the cumulative risk of exposure to infectious blood in the dialysis environment.(ABSTRACT TRUNCATED AT 250 WORDS)

Female↗
PubMed1993

Community acquired viral hepatitis B and C in the United States.

In the United States, most reported cases of hepatitis B occur in adults as a result of behavioural, lifestyle, or occupational exposures, but a significant number of children also become infected in well defined settings. Although only 1-3% of acute hepatitis B virus (HBV) infections occur in children under 5 years of age, they account for 20-30% of all chronic infections. A new strategy for HBV prevention in the USA includes integration of HBV vaccine into childhood immunisation schedules. Vaccination strategies that target high risk groups have not been effective. To determine the frequency and severity of community acquired chronic hepatitis C, patients with acute non-A, non-B hepatitis identified in four sentinel counties in the United States were followed prospectively. Hepatitis C virus (HCV) infection was found in 106 (82%) of 130 patients. Ninety three per cent of the HCV positive patients had a risk factor for their infection: 59% parenteral, 6% sexual or household, and 28% low socioeconomic level. Chronic hepatitis developed in 62%, independently of the risk factor for infection. HCV-RNA persisted in most patients, including those with biochemical resolution of their hepatitis. This study suggests that HCV may be a major cause of liver disease and persistent viraemia in the United States.

Adolescent↗
PubMed1993

The detection, transmission, and outcome of hepatitis C virus infection.

Hepatitis C virus (HCV), the primary etiologic agent of parenterally transmitted non-A, non-B hepatitis, is a major cause of acute and chronic hepatitis and cirrhosis worldwide. The most efficient transmission of HCV is associated with percutaneous exposures to blood, but such exposures account for less than half of reported cases. Sexual, household, and perinatal transmission also seem to occur, but the risks associated with these types of exposures are still unknown. Virtually all persons with acute HCV infection seem to become chronically infected, and chronic liver disease with persistently elevated liver enzymes develops in an average of 67%, independent of the source for infection. The extraordinarily high rate of persistent infection observed in humans and the lack of protection against rechallenge with homologous HCV strains demonstrated in experimental studies in chimpanzees suggest that HCV fails to induce an effective neutralizing antibody response. This raises major concerns for the development of effective passive or active immunization against hepatitis C, and prevention may depend on a better understanding of the factors that facilitate the transmission of HCV infection.

Chronic Disease↗
PubMed1992

The natural history of community-acquired hepatitis C in the United States. The Sentinel Counties Chronic non-A, non-B Hepatitis Study Team.

BACKGROUND: Chronic liver disease develops in more than half of patients with post-transfusion hepatitis C, but little is known about the natural history of community-acquired hepatitis C. METHODS: In 1985 and 1986 we identified adults with acute non-A, non-B hepatitis in four counties in the United States and followed them prospectively. We used three markers to detect hepatitis C virus (HCV) infection in stored samples of serum: antibody to HCV (anti-HCV) detected by second-generation serologic assays; HCV RNA detected by polymerase-chain-reaction assay; and antibody to HCV antigen (anti-HCVAg) detected by fluorescent-antibody-blocking assay. RESULTS: Of 130 patients with non-A, non-B hepatitis, 106 (82 percent) had HCV infection, 93 were positive for anti-HCV, and 13 were positive only for HCV RNA or anti-HCVAg. Chronic hepatitis developed in 60 (62 percent) of 97 HCV-infected patients followed for 9 to 48 months, with no relation to the risk factors for infection. Ten of the 30 patients who had liver biopsies had chronic active hepatitis. In samples collected 42 to 48 months after the onset of hepatitis, HCV RNA was detected in 12 of 13 tested patients with chronic hepatitis and in all 15 tested patients with hepatitis that had resolved. Anti-HCV persisted in all but two of the initially positive patients, for a rate of antibody loss of 0.6 per 100 person-years. CONCLUSIONS: Patients with community-acquired hepatitis C have a high rate of chronic hepatitis. HCV may be a major cause of chronic liver disease in the United States, and in most patients HCV infection seems to persist for at least several years, even in the absence of active liver disease.

Adolescent↗
PubMed1992

Nosocomial transmission of hepatitis B virus associated with the use of a spring-loaded finger-stick device.

BACKGROUND AND METHODS: From June 1989 through March 1990, 26 patients, of whom 23 had diabetes, contracted acute hepatitis B virus (HBV) infection in a hospital in California. All 26 patients and one HBV carrier (also a diabetic) had been admitted to a single medical ward during the six months before the case patients became infected with HBV. To determine the source of the infection, we conducted a retrospective cohort study of the 72 patients with diabetes who had been admitted to the ward from January through December 1989 and a case-control study comparing the 3 nondiabetic patients who contracted hepatitis with 20 nondiabetic controls. RESULTS: The retrospective cohort study of all the patients with diabetes who were admitted to the ward during 1989 found that those who underwent capillary blood sampling by finger stick with a spring-loaded lancet device were more likely to contract HBV infection than those who did not have finger sticks (attack rate, 42 percent vs. 0 percent; P = 0.08). In addition, a dose-response relation was observed between the number of finger sticks received and the frequency of hepatitis B (P = 0.002). The case-control study found that all 3 of the nondiabetic patients who contracted hepatitis underwent finger-stick blood sampling with the device, as compared with none of the 20 nondiabetic controls (P = 0.0006). A review of nursing procedures indicated that the platform of the device was not routinely changed after each use; this finding suggested that contamination of the platform by HBV-infected blood was the mechanism of percutaneous transmission of HBV. CONCLUSIONS: Proper use of finger-stick devices as well as strict adherence to universal precautions to avoid contamination by blood are required to decrease the possibility of transmission of blood-borne pathogens among hospitalized patients.

Acute Disease↗
PubMed1992

Serologic identification of hepatitis E virus infections in epidemic and endemic settings.

Recombinant chimeric protein C2 containing the N-terminal region of trpE (37 kilodaltons [kDa]) and the C-terminal half (46.8 kDa) of the polypeptide encoded by ORF2 of the hepatitis E virus (HEV) genome was used for the construction of a Western blot diagnostic test for IgG and IgM antibodies to the virus (anti-HEV). (The C2 protein and the trpE protein devoid of C2 activity and used as a control for non-specific reactions were purified by recovery from sodium dodecyl sulfate-polyacrylamide gel electrophoresis [SDS-PAGE] and used for preparation of strips). Specificity of the test was proven with sera obtained from patients with acute hepatitis non-A, non-B, non-C (NANBNC) from outbreaks in different geographic regions of the world. IgG antibodies reactive to the recombinant C2 protein were detected in 93% of patients with acute hepatitis NANBNC and remained detectable in 89-100% of these patients 1-24 months after onset of jaundice. IgM antibodies were detected in 73% of patients within 26 days after onset of jaundice, in 50% 1-4 months after onset, in 6% 6-7 months after onset, and in no patients by 8 months after onset. When this test was used to identify sporadic hepatitis E cases in different regions of the world, such cases were found almost exclusively in areas where outbreaks of the disease had occurred and rarely in any other regions.

Adolescent↗
PubMed1992

Hepatitis C virus antigen in hepatocytes: immunomorphologic detection and identification.

Hepatitis C virus (HCV) antigen was detected immunohistochemically using fluorescein isothiocyanate-labeled immunoglobulin G fractions from chimpanzee and human sera strongly reactive with recombinant hepatitis C virus structural and non-structural proteins. The antigen was localized in the cytoplasm of hepatocytes in all 9 chimpanzees with acute hepatitis C, in 5 of 10 chimpanzees with chronic HCV infection, and in 11 of 12 patients with chronic hepatitis C. The specificity of the hepatocellular HCV and FITC-labeled probes for HCV was ascertained by blocking studies with paired serum samples obtained from 8 infected and uninfected chimpanzees or from 14 patients during the acute and chronic phases of HCV infection. Absorption experiments on FITC-labeled probes with selected host proteins (normal liver homogenate, plasma proteins, red blood cells) did not indicate cross reactivity of the probes with these antigens. Direct immunomorphologic evidence for the HCV specificity of hepatocellular HCV antigen deposits and the FITC-labeled polyclonal anti-HCVAg probe was established in absorption experiments using recombinant HCV nonstructural proteins. The putative HCV NS3 protein was the most prominent component of hepatocellular HCV antigen.

Adult↗
PubMed1992

Epidemiology of hepatitis A: seroepidemiology and risk groups in the USA.

Surveillance and seroepidemiological data are important in determining optimal hepatitis A vaccine strategies. In the USA, after a decade of declining rates, reported hepatitis A rates gradually increased from 9.2 cases per 100,000 population in 1983 to a peak of 14.4 per 100,000 in 1989. In 1991, 23,144 cases were reported, for a rate of 9.1 per 100,000. Since 1983, rates in males have been consistently 20% higher than in females. Rates in children, adolescents and adults up to 39 years old have been roughly equivalent and approximately threefold higher than for persons > or = 40 years old. Among reported cases in 1989, the most commonly reported risk factor was personal contact with a hepatitis A case (26%), followed by employment or attendance at a day-care centre (14%), a history of injecting drug use (11%), a history of recent international travel (4%), and association with a suspected food or waterborne outbreak (3%). Of cases, 42% had no known risk factor for infection. The prevalence of antibody to hepatitis A virus in the general US population was 38.2%, based upon testing of 9516 participants from the second National Health and Nutrition Examination Survey conducted from 1976 to 1980. Prevalence increased steadily with age, ranging from 11% in persons < 5 years of age to 74% in persons > or = 50 years old. Because some groups may be difficult to vaccinate prior to disease exposure (contacts of cases) or are difficult to reach (drug users or persons with unidentified risk), a selected risk group vaccination strategy may not be successful in reducing the disease burden in the USA.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Outbreak of hemodialysis-associated non-A, non-B hepatitis and correlation with antibody to hepatitis C virus.

Between January 1987 and October 1988, 35 (45%) of 77 patients undergoing chronic hemodialysis at one unit developed serum alanine aminotransferase (ALT) elevations suggestive of non-A, non-B hepatitis (NANBH). Patients were grouped by level of ALT elevation and presence of other etiologies for liver injury. All dialysis patients and staff were tested for antibody to hepatitis C virus (anti-HCV) by enzyme immunoassay on three occasions, 9 months apart; anti-HCV repeatedly reactive specimens were tested by the HCV neutralization assay. Household and sexual contacts of patients were tested once for anti-HCV. Case-patients were classified on the basis of clinical case definitions as probable, possible, questionable, and noncases, and by anti-HCV testing. Case-patients who had no history of transfusions or parenteral drug use were compared with noncases for common exposures. A total of 35% (27/77) of patients and none (0/24) of staff were anti-HCV-positive. Anti-HCV was found in 82% of probable cases, compared with 44% of possible cases, 44% of questionable cases, and 12% of noncases (P less than 0.01). Neither a common source nor direct person-to-person transmission could be documented; however, inadequate infection control measures demonstrated by lack of glove use and poor handwashing occurred during the exposure period. The incidence of HCV infection in patients over an 18-month period was 5%. Transmission of HCV to household or sexual contacts of patients did not appear to occur.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

A survey of hepatitis B surface antigen-positive blood donors: degree of understanding and action taken after notification.

All blood donors in the United States are tested for hepatitis B surface antigen (HBsAg) upon donation; if the test result is positive, the primary method of notification is by letter. To assess the effectiveness of this notification methods in stimulating HBsAg-positive donors to seek medical care and take preventive measures, 54 donors who tested HBsAg-positive on donation at the American Red Cross Blood Services. Atlanta Region, from January 1987 to July 1989 were interviewed. Thirty-nine donors (72%) had sought medical care after notification; the only motivating factor was that the letter told the donor to consult with his or her physician. Compared with donors who did not seek medical care, donors who did so were more likely to understand that the blood test was abnormal or that they were infected, and they were more likely to understand how hepatitis B virus is transmitted and that a vaccine is available. The differences were not significant, however. Of those donors who sought medical care, less than half received appropriate recommendations for protection of contacts, and of those who did, only one-third received prophylaxis. In-person and telephone interviews with donors, revision of the notification letter, and hepatitis B education programs targeted at medical care providers are suggested.

Blood Donors↗
PubMed1992

Multistate outbreak of hepatitis A associated with frozen strawberries.

A multistate outbreak of hepatitis A was traced to frozen strawberries processed at a single plant. Among 827 students and 60 teachers at an elementary school in Georgia during a 2-week period, 15 developed hepatitis A. Three months later, among 174 residents and 467 staff in an institution for the developmentally disabled in Montana during a 3-week period, 13 developed hepatitis A. Primary attack rates were 10% in the school and 8% in the institution. Cohort analysis in the school implicated consumption of strawberry shortcake in hepatitis A virus (HAV) infection (relative risk, 7.6; 95% confidence interval, 1.04-55.6). In the institution, such analysis implicated desserts and uncooked strawberries as the most biologically plausible vehicle of HAV transmission. Molecular analysis of HAV from patients in the two outbreaks revealed that the viral genomes were genetically identical and distinct from other known US strains. Contamination of food products before retail distribution is rare but should be considered in investigating common-source outbreaks of hepatitis A.

Adult↗
PubMed1992

Histopathology of community acquired chronic hepatitis C. The Sentinel Counties Chronic Non-A, Non-B Hepatitis Study Team.

As part of a study of community-acquired non-A, non-B hepatitis, liver biopsy specimens of 29 anti-HCV positive and four anti-HCV negative patients were evaluated in order to characterize the histopathologic changes of chronic hepatitis C. Liver biopsies were performed 6 to 46 mo after onset of the disease and repeat biopsies were obtained in 10 anti-HCV positive patients. The histologic diagnoses were chronic persistent hepatitis (45%), chronic active hepatitis (35%), and chronic lobular hepatitis (21%). Irrespective of the tissue diagnosis, the majority of the patients showed characteristic histologic abnormalities in the liver, particularly damage of the small and medium-sized bile ducts (76%), lymphoid aggregates in portal tracts (45%), enlarged macrophages (48%), and steatosis (31%). In 59% of the patients, two or more of these histologic abnormalities were combined. Similar histologic changes have previously been observed in non-A, non-B hepatitis, but only uncommonly in hepatitis A or hepatitis B. We conclude that the histopathologic findings in chronic hepatitis C are highly characteristic, although not pathognomonic.(ABSTRACT TRUNCATED AT 250 WORDS)

Biopsy↗
PubMed1991

Hepatitis C: a sleeping giant?

In the United States, non-A, non-B hepatitis accounts for 20-40% of acute viral hepatitis. Although it has traditionally been considered a transfusion-associated disease, non-A, non-B hepatitis is more likely to occur outside the transfusion setting. Surveillance data from the Centers for Disease Control show that in 1988 6% of patients with non-A, non-B hepatitis reported a history of blood transfusion, 46% parenteral drug use, 10% household or sexual exposure to a contact who had had hepatitis or exposure to multiple sex partners, 2% medical or dental employment involving frequent blood contact, less than 1% hemodialysis, and 40% no known source. Antibody to hepatitis C virus (anti-HCV) is found in the majority of patients with non-A, non-B hepatitis independent of the source of infection; however, antibody may not appear for 6 to 9 months after exposure or onset of illness. Limited serologic studies of the prevalence of anti-HCV in various population groups have found high anti-HCV rates (50-80%) in parenteral drug users and hemophiliacs, intermediate rates among the sexually active (5-15%), and low rates among health care workers (1%). In persons with acute or chronic hepatitis C, the presence of anti-HCV appears to indicate infectivity. Persons with no history of hepatitis who are anti-HCV positive may or may not be infectious. More sensitive and specific markers for the detection of hepatitis C virus will be needed to resolve this question.

Hepacivirus↗
PubMed1991

Hepatitis B: evolving epidemiology and implications for control.

Control and the possible elimination of transmission of HBV infection is possible with the appropriate use of hepatitis B vaccines. The prevention of chronic HBV infection has the potential of reducing the association burden of chronic liver disease and primary hepatocellular carcinoma. Worldwide, strategies for the effective use of hepatitis B vaccine have been developed and are being implemented in those areas where childhood transmission is the predominant source of chronic HBV infections. However, in the United States and other areas with "low" rates of HBV infection, current vaccination strategies have not been effective and have not fully taken into account the multifaceted epidemiology of HBV infection in those areas. Unfortunately, the majority of infections occur among adults who have been the most difficult to access, who acquire infection before they realize they are at risk, and where the changing epidemiology of HBV infections among the various risk groups only emphasizes the problems of vaccine delivery. In addition, the majority of persons receiving vaccine as a result of the current strategy to immunize adult high-risk groups have been persons who acquire HBV infection through occupational exposure, a group that accounted for no more than 5% of cases even before vaccine was introduced. The failure of the current immunization strategy to prevent a disease with significant health care and economic consequences is beginning to cause a reevaluation of this approach. A comprehensive approach to eliminating HBV transmission must address infections acquired during early childhood as well as those acquired by teenagers and adults.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1990

Risk factors for acute non-A, non-B hepatitis in the United States and association with hepatitis C virus infection.

The Centers for Disease Control conducted intensive surveillance for acute non-A, non-B hepatitis in four sentinel counties over a 7-year period. Testing for antibody to hepatitis C virus was performed with the newly developed enzyme immunoassay. The incidence of non-A, non-B hepatitis remained relatively stable (average, 7.1 cases per 100,000, but there were significant changes in disease transmission patterns. The proportion of patients with a history of blood transfusion declined from 17% to 6%, but the proportion with a history of parenteral drug use increased from 21% to 42%. The proportion of patients with histories of sexual exposure (6%), household exposure (3%), occupational exposure to blood (2%), or hemodialysis (0.6%) did not change over time. Antibody to hepatitis C virus was found in 45% of patients within 6 weeks of onset of illness and in 68% of patients followed up for at least 6 months. Patients with no history of transfusions were just as likely to be positive for antibody to hepatitis C virus as patients with transfusion-associated hepatitis, indicating that hepatitis C virus is the major causative agent of all non-A, non-B hepatitis in the United States.

Acute Disease↗