An international workshop on vaginal smear-based diagnosis of bacterial vaginosis was organized where 13 investigators scoring 258 slides with smears from vaginal fluid. Interobserver reproducibility of interpretations of Nugent scores, Hay/Ison scores and wet smear scores for the diagnosis of bacterial vaginosis was shown to be high. Detailed analysis of individual scoring results however indicated that basic standards of quality control to ensure robust individual readings of slides must be adhered to.

The first five cases of human tick-borne encephalitis in Norway were reported from Tromöya, in Aust-Agder County. Serum specimens from 317 dogs in the same geographic area were collected. An enzyme immunoassay demonstrated antibody to human tick-borne encephalitis virus in 52 (16.4%) of the dogs, which supports the notion of an emerging disease.

Mycoplasma pneumoniae antibodies were studied in 504 blood donors and 102 patients with infections not caused by M. pneumoniae with the use of enzyme immunoassay kits from ThermoLabsystems (L), Savyon (S), Bio-Rad (B) and Novitec (N). Detection frequencies of M. pneumoniae IgM in blood donors were 14.9% (L), 16.0% (S), 2.8% (B) and 3.8% (N), and in patients were 40.2% (L), 42.2% (S), 9.8% (B) and 16.7% (N). Detection frequencies of M. pneumoniae IgA were 68.5% (L) and 22.8% (S), and in 65 respiratory disease patients were 100% (L) and 53.8% (S). Thus, use of some kits may lead to overdiagnosis of M. pneumoniae infections.

Chlamydia trachomatis and C. pneumoniae are both important human pathogens. Antigenic cross‐reactivity between the two species may complicate serologic diagnosis of infection with one or the other agent. In this study we examined sera of persons with chlamydial infections and of healthy children by microimmunofluorescence (MIF) against C. trachomatis L2 antigen and against C. pneumoniae TW‐183 antigen to explore the degree of cross‐reactivity found by these two methods. Likewise, the cross‐reactivity seen by immunoblot with sera of rabbits immunized against one of the antigens when tested on the other was examined. While among healthy children stratified by age, MIF seropositivity to C. pneumoniae TW‐183 increased with age, no such trend was observed with respect to seropositivity to C. trachomatis L2 antigens, and 81% of children seropositive to TW‐183 did not react on L2 antigen. Moreover, 27% of those positive on L2 antigen were negative on TW‐183. Immunoblot analysis showed much greater antibody cross‐reactivity than that detected by MIF. The immunoblot cross‐reactivity was probably not attributable solely to double infection since sera of rabbits immunized to only one species of chlamydia reacted strongly with both chlamydiae in immunoblot analysis. The data presented need to be taken into account in the development of serologic tests based on a small number of antigens or on partially denatured antigens.

SUMMARY The efficiency of an immunoperoxidase serological assay and culture of Chlamydia trachomatis were compared in 127 women seeking first trimester abortion. Serum IgG and IgA antibodies specific for C trachomatis wer.e detected by a single serovar (L2) inclusion immunoperoxidase assay (IPA). Eighty (63%) women were seropositive for chlamydial IgG and 31 (24%) for IgA antibodies. C trachomatis was isolated from 21 of 127 (17%) women. Twenty of the 80 women (25%) seropositive for specific IgG antibodies and one of 47 (2%) patients without these antibodies were culture positive (p < 0-001). Compared with isolation, chlamydial antibodies at a titre of > 16 showed high sensitivity and negative predictive value (95% and 98%, respectively), but low specificity and efficiency (43% and 52%, respectively). Chlamydial IgA antibodies at a titre of > 8 showed low sensitivity (52%), but a higher specificity, negative predictive value, and efficiency of 81%, 90%, and 76%, respectively. C trachomatis IgG antibodies at a titre of 16 as determined by IPA can be used as an efficient negative exclusion marker for active chlamydial infection in screening women seeking abortion. Postabortal salpingitis may complicate postoperative recovery in about 20% of women infected with C trachomatis.' To avoid this complication screening for C trachomatis by direct immunofluorescence and culture isolation has recently gained wider application for women wanting an abortion. Although culture is the standard reference method, it is costly, time consuming, and requires considerable experience. The results may also arrive too late and therefore be oflittle help in deciding on appropriate management. Direct detection methods are speedier, but they, too, require expensive equipment, skill, and may be less sensitive than culture.2 In this study we compared the efficiency of a new and sensitive serological method with the standard cell culture. The results of cell culture were correlated with serology for specific chlamydial IgG and IgA antibodies by the single serovar (L2) IPA. Patients and methodsOne hundred and twenty seven women presenting for first trimester abortion were included in the study. The