The first combined vaccine against hepatitis A and B: an overview.

Hepatitis A and B infections are prevalent world-wide and are a significant cause of morbidity and mortality. A vaccine providing dual protection against hepatitis A and B is now available (Twinrix, SmithKline Beecham Biologicals). Six pivotal vaccine trials, involving 843 healthy adults, aged between 17 and 60 years and vaccinated following a 0, 1, 6 month schedule are discussed. At month 2 more than 99% of the vaccinees were seropositive for anti-HAV and 84% were protected against hepatitis B. The third dose induced a 12-fold increase in geometric mean titres (GMTs) to 5404 mIU/ml. One month after completion of the vaccination course nearly all vaccinees had protective titres against hepatitis B with a GMT of 4818 mIU/ml. Long term follow-up data until month 48 is available for two studies. At month 48 all 129 vaccinees sampled were still positive for anti-HAV antibodies and > 95% were still protected against hepatitis B. The combined hepatitis A and B vaccine Twinrix proves to be consistently safe, well tolerated and highly immunogenic and compares well with serological responses reached with monovalent vaccines. This combined hepatitis A and B vaccine offers more convenience, potentially better compliance and lower administration costs.

[An outbreak of methicillin-resistant Staph aureus in a nursing home]. / Een uitbraak van meticilline-resistente Staphylococcus aureus in een verpleeghuis.

The introduction of methicillin-resistant Staphylococcus aureus (MRSA) in an Amsterdam nursing home (312 beds) by a patient discharged from a local hospital, the spread of this strain to other residents and staff of the nursing home and the actions taken to prevent this spread are described. During the period when this MRSA strain was circulating residents and staff members were checked periodically for presence of MRSA. In spite of all preventive measures as implemented in Dutch hospitals (including isolation of infected residents) additional residents (in a total of 8) and staff members acquired the MRSA strain. Relaxation of the precautions (no more isolation) and continued instruction of the members of the staff was attended by a decrease of further contamination. Four of 8 residents died while being colonised or infected. The course of this epidemic illustrates that limited precautions and proper training of staff in hygiene can restrict spread of MRSA in nursing homes.

Early antihepatitis C virus response with second-generation C200/C22 ELISA.

Detection of early antibody to hepatitis C virus (HCV) by a new second-generation C200/C22 anti-HCV enzyme-linked immunosorbent assay (ELISA) and a four-antigen recombinant immunoblot assay (4-RIBA) was compared with the first-generation anti-HCV C100 ELISA using sequential serum samples of 9 recipients who were infected with HCV, as detected by polymerase chain reaction after transfusion of blood products. Within 26 weeks after transfusion, 9/9 (100%) recipients seroconverted with C200/22 ELISA, and 6/9 (67%) seroconverted with C100 ELISA. Compared with C100 ELISA, C200/C22 ELISA seroconversion occurred simultaneously in 3 cases, 5-6 weeks earlier in 3 other cases, and 20 weeks earlier in 1 case. Seven of 9 (78%) recipients became positive, and 2/9 (22%) became indeterminate with 4-RIBA. In 8 cases with clinical posttransfusion hepatitis non-A, non-B (PTH-NANB), anti-HCV C200/C22 ELISA seroconversion occurred 2-17 (mean 6) weeks after the onset of hepatitis. In 6 cases of PTH-NANB, anti-HCV C100 ELISA seroconversion occurred 2-26 (mean 9) weeks after the onset of hepatitis. It is concluded that the second-generation C200/C22 ELISA is more sensitive than the C100 ELISA for the detection of antibody during early HCV infection. Indeterminate 4-RIBA results are found in the early phase of HCV infection.

The course of the HIV epidemic among intravenous drug users in Amsterdam, The Netherlands.

To determine if behavioral changes in intravenous drug users in Amsterdam have retarded the HIV (human immunodeficiency virus) epidemic in this group in recent years, we report that: HIV-antibody seroprevalence in annual samples of injectors has been constant over the years 1986-89; HIV-antibody incidence in a cohort of injectors appears to have decreased from 1986 to 1987 and stabilized after that until 1989; acute hepatitis B incidence in all drug users in Amsterdam declined rapidly between 1985-89. It is concluded that changes in drug use behavior so far appear to have resulted in a stabilization of the epidemic among injectors, at a level with a still disturbingly high incidence rate of 5-6 per 100 person-years.

Prevalence of anti-HCV antibodies confirmed by recombinant immunoblot in different population subsets in The Netherlands.

The prevalence of antibodies to hepatitis C virus (anti-HCV) was studied in various population subsets in the Netherlands with anti-HCV C100 enzyme linked immunosorbent assay (ELISA), and confirmed with recombinant immunoblot assay (RIBA). Anti-HCV C100 ELISA positivity and RIBA positivity were found in 39 (0.7%) and 5 (0.1%) of 5,434 blood donors from Amsterdam; 25 (5%) and 2 (0.4%) of 481 blood donors from Surinam (South America); 19 (9%) and 2 (1%) of 213 multitransfused patients; 28 (4%) and 15 (2%) of 633 hemodialysis patients; 179 (80%) and 150 (67%) of 225 hemophilia A and B patients; 8 (80%) and 4 (40%) of 10 intravenous drug abusers; 18 (15%) and 2 (2%) of 119 anti-HIV-positive homosexual men; 2 (2%) and none of 106 anti-HIV-negative homosexual men; 6 (32%) and 3 (16%) of 19 patients with acute hepatitis non-A, non-B (NANBH); 13 (65%) and 8 (40%) of 20 patients with chronic NANBH and/or cryptogenic cirrhosis; and 4 (40%) and 1 (10%) of 10 patients with idiopathic autoimmune chronic hepatitis. Among blood donors, a positive correlation between a history of jaundice after the age of 18 years and the presence of RIBA-confirmed anti-HCV antibodies was found. Among both blood donors and hemodialysis patients, a positive correlation of RIBA-confirmed anti-HCV positivity with elevated alanine aminotransferase levels, but not with the presence of anti-hepatitis B core antibodies was found.(ABSTRACT TRUNCATED AT 250 WORDS)

Infectivity of blood seropositive for hepatitis C virus antibodies.

Stored serum samples from 5150 blood product transfusions and 383 recipients were tested for antibodies to hepatitis C virus (anti-HCV) by a recombinant enzyme-linked immunosorbent assay (ELISA) as part of a prospective study on post-transfusion non-A, non-B hepatitis (NANBH). Donor cofactors associated with HCV infectivity of anti-HCV-positive blood products were raised alanine aminotransferase concentrations (6 of 9 infective vs 1 of 26 not infective); a mean ELISA optical density/cut-off ratio greater than or equal to 2 (7 of 9 vs 9 of 26); both preceding factors (together in 6 blood products, all of which transmitted infection); and persistent donor anti-HCV seropositivity. Use of anti-HCV screening to prevent post-transfusion NANBH was compared with measurement of alanine aminotransferase concentrations: a corrected efficacy of 63% and 65%, a specificity of 93% and 64%, and a positive predictive value of 16.2% and 3.6% were found, respectively; 0.7% or 3.8% of blood donations, respectively, would be discarded. Blood donor screening for anti-HCV is recommended to reduce the incidence of post-transfusion NANBH.

Anti-hepatitis C antibodies and non-A, non-B post-transfusion hepatitis in The Netherlands.

In a prospective study carried out in the Netherlands (1984-86) to establish the incidence of post-transfusion hepatitis non-A, non-B (PTH-NANB) in patients undergoing open heart surgery, 393 patients received 5315 blood product transfusions. PTH-NANB developed in 9 patients (index cases); stored serum samples from these patients and from 9 control patients, matched for age, sex, and number of blood product transfusions, as well as serum samples of all implicated blood products, were selected retrospectively. Sera were tested under code with a radioimmunoassay for the detection of antibodies to hepatitis C virus (anti-HCV). PTH-NANB patients received 151 blood product transfusions and control patients 140. 4 of 9 PTH-NANB patients (3/5 chronic, 1/4 acute resolved hepatitis) and 0/9 controls seroconverted. 7 of the transfusions given to PTH-NANB patients but none of those given to control patients were anti-HCV positive. In 7 of 9 serum sets from PTH-NANB index cases plus implicated donors, either a donor or the recipient was anti-HCV positive. Among the donors implicated in transmission of PTH-NANB there was a strong correlation between raised alanine aminotransferase levels and the presence of anti-HCV antibodies.