PubMed Health⌕ Search

Biomedical subjects

S J McConkey

Publications and source records attributed to S J McConkey.

9 recordsLinked to original sources
PubMed2006

Similar long-term vaccine efficacy of two versus three doses of HBV vaccine in early life.

WHO currently recommends three vaccinations against hepatitis B to provide optimal protection against infection and carriage. However, immunological theory and mathematical modelling suggest that similar protection could be induced with two doses, and trials among adolescents and adults have shown comparable rates for both primary seroprotection and geometric mean titres following vaccination. We determined vaccine efficacy among 60 children who only received two doses of hepatitis B vaccine as infants and among 463 children who had received three doses after 4-7 years of follow-up. Vaccine efficacy among the two-dose group was 86.3% against anti-HBc positivity (infection) and 92.3% against HBsAg positivity (carriage), which was similar to the vaccine efficacy found among the participants who had received three doses. To confirm this comparable vaccine efficacy a randomised controlled non-inferiority trial with long-term follow-up is needed.

Child, Preschool↗
PubMed2006

Long-term protection against carriage of hepatitis B virus after infant vaccination.

BACKGROUND: Carriage of hepatitis B virus (HBV) is a major risk factor for liver cirrhosis and hepatocellular carcinoma. Infant vaccination has been effective in preventing horizontal transmission during early childhood. It is unknown whether protection is maintained into early adulthood. METHODS: In 1984, early childhood vaccination was introduced in 2 rural Gambian villages. In 2003, serological assessment of 81.5% of 1,350 eligible participants 1-24 years old was done, to determine vaccine efficacy against infection and carriage. RESULTS: Overall vaccine efficacy against infection and carriage was 83.4% (95% confidence interval [CI], 79.8%-86.6%) and 96.5% (85% CI, 93.9%-98.9%), respectively. Vaccine efficacy against infection was similar when restricted to primary responders (85.3%), but a significant effect of peak antibody concentration was found. Both vaccine efficacy and levels of hepatitis B surface antibody (anti-HBs) decreased with age, resulting in a vaccine efficacy against infection and carriage among 20-24-year-old participants of 70.9% (95% CI, 60.4%-80.5%) and 91.1% (95% CI, 75.8%-100%), respectively. Fifteen years after vaccination, fewer than half of the vaccinees had detectable anti-HBs. The prevalence of carriage in the unvaccinated population was similar to the prevalence 20 years earlier. CONCLUSIONS: HBV vaccination early during life can provide long-lasting protection against carriage, despite decreasing antibody levels. The role played by subclinical boosting and the necessity of a booster need to be evaluated.

Adolescent↗
PubMed2002

Evaluation of a rapid-format antibody test and the tuberculin skin test for diagnosis of tuberculosis in two contrasting endemic settings.

OBJECTIVE AND SETTING: We evaluated a rapid-format antibody card test and the tuberculin skin test for diagnosis of active tuberculosis (TB) in high (Cairo, Egypt) and low (St. Louis, USA) prevalence areas. DESIGN: Prospective study of hospitalized TB patients and controls with other chest diseases. RESULTS: Test performance varied significantly in the two study sites. The antibody test detected 87% of 71 smear-positive pulmonary TB cases (86% of smear-negative pulmonary cases and 48% of TB meningitis cases) in Egypt; specificity was 82%. The tuberculin test was highly sensitive in Egypt in subjects with pulmonary TB (100%) but not in those with meningitis (23%); specificity was 70%. The sensitivity and specificity of the antibody test in St. Louis were 29% and 79%, respectively; 50% of St. Louis TB cases and 15% of controls had positive tuberculin tests. CONCLUSIONS: This convenient antibody card test may have value for diagnosis of patients suspected of having TB in high prevalence areas like Egypt. However, the specificity of the test is too low for it to be useful as a screening test. Our results suggest that neither the antibody test nor the tuberculin test have much diagnostic utility in low prevalence settings like St. Louis.

Adult↗
PubMed1999

Results of a comprehensive infection control program for reducing surgical-site infections in coronary artery bypass surgery.

OBJECTIVE: To evaluate the efficacy of a comprehensive infection control program on the reduction of surgical-site infections (SSIs) following coronary artery bypass graft (CABG) surgery. DESIGN: Prospective cohort study. SETTING: 1,000-bed tertiary-care hospital. PATIENTS: Persons undergoing CABG with or without concomitant valve surgery from April 1991 through December 1994. INTERVENTIONS: Prospective surveillance, quarterly reporting of SSI rates, chlorhexidene showers, discontinuation of shaving, administration of antibiotic prophylaxis in the holding area, elimination of ice baths for cooling of cardioplegia solution, limitation of operating room traffic, minimization of flash sterilization, and elimination of postoperative tap-water wound bathing for 96 hours. Logistic regression models were fitted to assess infection rates over time, adjusting for severity of illness, surgeon, patient characteristics, and type of surgery. RESULTS: 2,231 procedures were performed. A reduction in infection rates was noted at all sites. The rate of deep chest infections decreased from 2.6% in 1991 to 1.6% in 1994. Over the same period, the rate of leg infections decreased from 6.8% to 2.7%, and of all SSI from 12.4% to 8.9%. The adjusted odds ratio (OR) for all SSIs for the end of 1994 compared to December 31, 1991, was 0.37 (95% confidence interval [CI95], 0.22-0.63). For deep chest and mediastinal infections, the adjusted OR comparing the same period was 0.69 (CI95, 0.28-1.71). CONCLUSIONS: We observed significant reductions in SSI rates of deep and superficial sites in CABG surgery following implementation of a comprehensive infection control program. These differences remained significant when adjusted for potential confounding covariables.

Adult↗
PubMed1997

Leptospirosis in the Republic of Ireland: 1985 to 1996.

Official government statistics and serological laboratory data provide limited information about the incidence of leptospirosis in the Republic of Ireland. The mean annual notified incidence in the Republic of Ireland from 1985 to 1996 was 1.3/million. The incidence according to hospital discharge diagnosis was higher at 4.9/million. One hundred and seventy-five serologically confirmed cases of leptospirosis were reported from 1986 to 1996, giving a mean annual incidence of 4.5/million. The true incidence of leptospirosis in the Republic of Ireland is probably higher, as hospital discharge data are incomplete and full serological testing was not always performed. Our data indicate that leptospirosis is an underestimated public health problem with only 26% of cases being notified. A national communicable disease surveillance centre in the Republic of Ireland would facilitate better monitoring and understanding of this disease.

Adult↗
PubMed1989

Enterobacter cloacae in a haematology/oncology ward--first impressions.

The observation that Enterobacter cloacae has emerged as a cause of infection in a haematology/oncology ward prompted a prospective study over an eight-month period. Sensitivity to antibiotics, plasmid screening and typing methods were used to describe the epidemiology of the organism which was isolated from 22 patients. There was evidence of a limited amount of cross infection. No common sources were found. A large number of distinct strains were identified. E. cloacae infection was associated with prolonged profound leucopenia and broad-spectrum antibiotic therapy.

Adolescent↗