ABSTRACT
Studies have suggested that positivity can be used to estimate the prevalence of Chlamydia trachomatis in large-scale chlamydia screening programmes. A recent pilot of opportunistic screening in England estimated that the prevalence among 16-24-year-old women in Portsmouth and Wirral was 9.8% and 11.2%, respectively. This study assessed the continued validity of positivity as an approximate for prevalence. We re-analysed data from the Chlamydia Screening Pilot to estimate positivity,calculated as total positive tests divided by total tests, and compared these estimates with the previously reported prevalence, measured as the number of women testing positive divided by the total number of women screened. Overall positivity was 9.4% in Portsmouth and 11.0% in the Wirral; these estimates were not statistically different from prevalence, regardless of health-care setting, age group or symptoms. We conclude that positivity can be used as a proxy for prevalence.
Subject(s)
Chlamydia Infections/diagnosis , Chlamydia Infections/epidemiology , Mass Screening , Adolescent , Adult , Data Interpretation, Statistical , Female , Humans , Pilot Projects , Prevalence , Reproducibility of Results , United KingdomABSTRACT
Sera from 105 blood donors and eight patients with brucellosis were examined for anti-brucella IgG and IgM by a radioimmune technique. A pooled standard was used for comparison and evaluation. The upper limit of the 99% confidence interval on the mean of both immunoglobulin classes in blood donor sera was below 7 units/ml. Antibody response was shown in three acute, two relapsing, two chronic, and one asymptomatic cases. Values of up to 300 units/ml of both classes were found in the acute cases. Chronic sufferers showed lower concentrations of antibody. Relapsing cases showed increases comprising mainly IgG. The assay method, which shows general concordance with the results of conventional tests. is useful and measures individual immunoglobulin classes directly.
Subject(s)
Antibodies, Bacterial/analysis , Brucella/immunology , Brucellosis/immunology , Immunoglobulin G/analysis , Immunoglobulin M/analysis , Humans , Male , RadioimmunoassaySubject(s)
Metronidazole/blood , Humans , Intestinal Absorption , Metronidazole/administration & dosage , Rectum , SuppositoriesABSTRACT
In a study of 188 patients and 109 controls, the detection of antibody by counterimmunoelectrophoresis was used as a diagnostic aid in human infections with Bacteroides fragilis. It was found that positive results indicated current infection and negative results were not conclusive. The method used was simple, rapid, and easily performed in a routine laboratory, but further work is needed to enhance antigen potency.
