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Biomedical subjects

C E Stevens

Publications and source records attributed to C E Stevens.

At least 163 records · Page 9Linked to original sources

A controlled clinical trial of the efficacy of the hepatitis B vaccine (Heptavax B): a final report.

A controlled, randomized, double-blind trial in 1,083 homosexual men from New York confirmed that a highly purified, formalin-inactivated vaccine against hepatitis B prepared from HBsAg positive plasma, is safe immunogenic, and highly efficacious. Over 95% of vaccinated subjects developed antibody against the surface antigen. Vaccine-induced antibody persisted for the entire 24-month follow-up period. The attack rate of all hepatitis B virus infections (excluding conversions of anti-HBc alone) was 3.2% in vaccine recipients compared with 25.6% in placebo recipients (p less than 0.0001). In those who received all three doses of vaccine, of 40 micrograms each, the protective efficacy rate was close to 100%. The vaccine protects against acute hepatitis B, asymptomatic infection, and chronic antigenemia. There is reason to assume that the vaccine is also partially effective when given postexposure.

Adult↗

Efficacy of hepatitis B immune globulin for prevention of perinatal transmission of the hepatitis B virus carrier state: final report of a randomized double-blind, placebo-controlled trial.

A randomized double-blind, placebo-controlled efficacy trial of hepatitis B immune globulin (HBIG) for prevention of the mother-to-infant transmitted HBsAg carrier state was conducted in Taiwan where the carrier rate in the general population is 15 to 20%. HBIG was given immediately after birth to infants of e antigen positive HBsAg carrier mothers, and all infants were followed for at least 15 months. Among 61 placebo recipients, the carrier rate was 92%; compared with 26% among 57 infants who received 0.5 ml HBIG at birth, 3 months, and 6 months, and 54% among 67 infants who received a single 1.0 ml dose of HBIG at birth only. Efficacy was 71 and 42%, respectively, for the two treatment schedules. The most common response of HBIG-treated infants was passive-active immunization which was 27% in the single-dose group and 61% in the three-dose group. Some of the infants who became carriers were probably infected as HBIG protection waned, and we expect that higher efficacy can be achieved by hepatitis B vaccine in conjunction with HBIG.

Carrier State↗

Occupational risk for hepatitis C virus infection among New York City dentists.

Health-care workers have an occupational risk of infection with hepatitis C virus (HCV). However, neither the magnitude of this risk nor the practices associated with it have been defined. Since dentists have numerous patients and are exposed to blood, they are likely to have the maximum risk. Therefore, we have assessed occupational risk for HCV infection among dentists in the New York City area. Individuals who admitted present or previous intravenous drug use or (men) who were homosexual or bisexual were excluded. Demographic, occupational, and behavioural data were recorded, and sera were tested for antibodies to HCV (anti-HCV). Anti-HCV was found in 8 (1.75%) of 456 dentists compared with 1 (0.14%) of 723 controls (odds ratio [OR] 12.9, 95% confidence interval [CI] 1.7 to 573). Anti-HCV was found in 4 (9.3%) of 43 oral surgeons compared with 4 (0.97%) of 413 other dentists (OR 10.5, 95% CI 1.9 to 58). Seropositive dentists claimed to have treated more intravenous drug users in the week (p = 0.04) or month (p = 0.03) before the study than did seronegative dentists. Our findings show that dentists are at increased risk for hepatitis C infection. All health-care workers should regard patients as potentially infected with a communicable bloodborne agent.

Adult↗

Hepatitis B virus contains pre-S gene-encoded domains.

One of the open reading frames on hepatitis B virus (HBV) DNA comprises the coding region (designated the env gene) for the virus envelope proteins. Studies on messenger RNA transcription suggest that this gene has the potential to code for three related proteins: (1) a protein of 226 amino acids identified as a major protein constituent of the HBV envelope, termed S-protein; (2) a protein with 55 additional amino acids at the N-terminal coded for by a portion of the env gene upstream of the S-gene (pre-S); (3) a protein corresponding to the entire env gene (pre-S + S). Synthetic peptides from the N-terminals of proteins (2) and (3), and antisera to them have been used to study the occurrence and properties of pre-S sequences. The results presented here provide unambiguous evidence that all three env encoded proteins are present in HBV particles; synthetic peptides corresponding to the gene encoding pre-S are highly immunogenic and can be used in diagnostic tests for detection in human sera of antibodies preferentially recognizing HBV; such antibodies, specific for pre-S determinants, are elicited during hepatitis B infection and by immunization with HBV proteins (2) and (3); the hepatitis B vaccine licensed in the United States does not contain pre-S proteins; and the pre-S proteins of the HBV envelope contain domains specifically recognized by liver cells. These findings suggest that pre-S determinants are important in virus-neutralizing responses and should be present in HBV vaccines.

Antibody Specificity↗

Serologic evidence of hepatitis A and B virus infections in thalassemia patients: a retrospective study.

To determine the current risk of hepatitis B virus (HBV) infection in multiply transfused thalassemia patients, we tested sera from such patients in New York City for the hepatitis B surface antigen (HBsAg) and its antibody (anti-HBs) using radioimmunoassay techniques. Altogether 48 per cent of the patients had either HBsAg (4.5%) or anti-HBs (43.9%) positive sera. The prevalence of these HBV markers was related to both the number of units transfused and the year blood transfusion therapy was begun, although evidence suggested that the latter factor had the greatest influence. Donor HBsAg screening began in New York in 1969, and only one patient first transfused since that time had HBV marker positive serum. Thus, multiply-transfused thalassemia patients now appear to be at little risk of HBV infection from transfusions. Sera were also tested for antibody to the hepatitis A virus (anti-HA) using immune adherence hemaglutination. Anti-HA prevalence was only 4.9 per cent, no greater than rates reported among nontransfused children, providing evidence against a significant role for blood transfusions in hepatitis A virus transmission.

Adolescent↗

Human T-cell lymphotropic virus in volunteer blood donors.

Serum samples collected in 1985 and 1986 from 18,257 donors to the Greater New York Blood Program were screened by enzyme-linked immunoassay for antibody to human T-cell lymphotropic virus (anti-HTLV). Fifteen samples (0.08%) were confirmed positive: 7 by radioimmunoprecipitation assay (RIPA) alone, 6 by Western blot alone, and 2 by combined results from both tests. One donor, whose original test result was uninterpretable because multiple nonspecific bands were present on RIPA, clearly tested positive on subsequent specimens. Follow-up testing of individuals with this type of result may be needed to resolve their HTLV status. Anti-HTLV prevalence increased with age and was significantly more common in black or Hispanic donors and in those born in the Caribbean than in other donors. All anti-HTLV-positive donors were negative for antibody to HIV-1, and only one donor (7% of those positive) would have been excluded by any of the routine donor screening tests used at that time.

Blood↗

Treatment of concomitant Neisseria gonorrhoeae and Chlamydia trachomatis infections in women: comparison of trimethoprim-sulfamethoxazole with ampicillin-probenecid.

Sixty-nine women with known or suspected uncomplicated gonorrhea were treated randomly either with a single dose of 3.5 g of ampicillin plus 1 g of probenecid or with four doses of trimethoprim-sulfamethoxazole (TMP-SMZ) in two double-strength tablets (160 mg of TMP plus 800 mg of SMZ) twice daily for two days. Overall, 56 (81%) of the women had gonococcal infections, 26 (38%) had chlamydial infections, and 23 (33%) had coexisting Chlamydia trachomatis and Neisseria gonorrhoeae infections. Among the women with genital or anal gonorrhea, two (9%) of 23 treated with TMP-SMZ and three (12%) of 25 treated with ampicillin and probenecid remained infected. TMP-SMZ cured four of four pharyngeal gonococcal infections. C. trachomatis was isolated at the first posttreatment visit significantly more often after treatment with ampicillin and probenecid (10 of 11 times) than after treatment with TMP-SMZ (1 of 10 times; P = 0.003). However, at the second follow-up visit, C. trachomatis was isolated from 30% of the women treated with TMP-SMZ. The area of ectopic columnar epithelium (ectopy) on the ectocervix and edema of this area were highly correlated with the presence of C. trachomatis, and persistence of C. trachomatis was associated with persistent edema of ectopy and with friability. TMP-SMZ is as effective as ampicillin-probenecid for the treatment of uncomplicated genital gonorrhea in women and may be more effective for the treatment of pharyngeal gonorrhea. The optimal dose and duration of TMP-SMZ therapy for C. trachomatis infection requires further study.

Adolescent↗