Seroepidemiological study of gonorrhoea in Ethiopian women. 2. Socioeconomic picture.

OBJECTIVES--To determine aetiological factors associated with the prevalence of gonorrhoea in Ethiopian women to enable subsequent formulation of intervention policies. SUBJECTS--1851 Ethiopian women: 50% symptomatic, 50% asymptomatic. SETTING--Gynaecological outpatient departments, antenatal, postnatal and family planning clinics (Ethiopian Family Guidance Association (EFGA)), in two teaching hospitals and a mother and child health centre in Addis Ababa, Ethiopia. METHODS--Using the indirect haemagglutination test with gonococcal pilus antigen, sera were tested for the presence of gonococcal antibodies indicating past or present infection. The socioeconomic facts were analysed against gonococcal seropositivity of these women. RESULTS--Gonococcal infection was associated with very early age at first marriage and first coitus, more than one sexual partner and marital status/profession. The highest prevalence and titres were found in bargirls (100%) prostitutes (89%) and sellers of local beer (85%). The lowest prevalence and titres were found in the highest income group, those married over the age of 18 years, those with only one husband or sexual partner, and those with a sexual life of less than 5 years duration. CONCLUSIONS--National measures which could contribute to reduction and control of gonorrhoea include effective raising of the age of first marriage and first coitus, as has already been defined by law; the education of all girls up to fifth grade or equivalent; the provision of financial support to prevent widows and divorcees from drifting into prostitution; regular health checks and treatment of prostitutes; and education of men. While gonorrhoea per se is a major public health problem, our findings must have serious implications in the wider context of possible transmission of HIV through the community.     

Seroepidemiological and socioeconomic studies of genital chlamydial infection in Ethiopian women.

OBJECTIVE--To measure the prevalence of chlamydial genital infection in Ethiopian women attending gynaecological, obstetric and family planning clinics; to identify the epidemiological, social and economic factors affecting the prevalence of infection in a country where routine laboratory culture and serological tests for chlamydial species are unavailable; to determine the risk factors for genital chlamydial infection in those with serological evidence of other sexually transmitted diseases. SUBJECTS--1846 Ethiopian women, outpatient attenders at two teaching hospitals and a mother and child health centre in Addis Ababa, Ethiopia. SETTING--Gynaecological outpatient department, antenatal, postnatal and family planning clinics. METHODS--Sera were tested for type-specific anti-chlamydial antibodies using purified chlamydial antigens (C. trachomatis A-C (CTA-C), C. trachomatis D-K (CTD-K), Lymphogranuloma venereum (LGV1-3), and C. pneumoniae (CPn)), in a micro-immunofluorescence test. The genital chlamydia seropositivity was analysed against patient's age, clinic attended, ethnic group, religion, origin of residence, age at first marriage and first coitus, income, number of sexual partners, duration of sexual activity, marital status/profession, obstetric and contraceptive history, and seropositivity for other sexually transmitted diseases. RESULTS--Overall exposure to chlamydia species was found in 84%, genital chlamydial infection in 62%, and titres suggestive of recent or present genital infection in 42% of those studied. Genital chlamydial infection was highest (64%) in family planning and lowest (54%) in antenatal clinic attenders. Exposure to genital chlamydia species was influenced by ethnic group and religion. Those married and sexually active under 13 years of age had greater exposure (69%) to genital chlamydial infection than those first sexually active aged over 18 (46%). Prevalence of infection was highest in those with more than five sexual partners (78%) and in bargirls (84%). The lowest income groups had a higher prevalence (65%) of genital chlamydial infection than the wealthiest (48%). Multivariate analysis showed the most important factors to be age at first coitus, religion, prostitution and present age of the woman in that order. Risk for genital chlamydial infection was increased in those with seropositivity for syphilis, gonorrhoea, HSV-2 but not HBV infection. CONCLUSION/APPLICATION--Chlamydial genital infections are highly prevalent in both symptomatic and asymptomatic Ethiopian women. The high prevalence of infection reported reflects a complexity of socioeconomic factors: very early age at first marriage and first coitus, instability of first marriage, subsequent divorce and remarriage or drift into prostitution, all of which are influenced by ethnic group, religion and poverty--together with transmission from an infected group of prostitutes by promiscuous males to their wives, lack of diagnostic facilities and inadequate treatment of both symptomatic and asymptomatic men and women. The problem of chlamydial disease in Ethiopia needs to be addressed urgently in the context of control of STD.     

Epidemiology of gonococcal and chlamydial infections in Harrow and Brent.

OBJECTIVE: To describe the epidemiology and associated clinical features of gonorrhoea and chlamydial infection and to develop a profile of sexually transmitted diseases (STDs) in an outer London health district. DESIGN: Hospital-based retrospective study. SETTING: Genitourinary medicine clinic, Northwick Park Hospital, Harrow and Brent Health Authority. SUBJECTS: 70 male and female individuals with gonorrhoea and 129 with chlamydial infection, diagnosed consecutively over 28 months in 1992-94. RESULTS: More men than women had gonorrhoea (43 versus 27) but more women than men had chlamydial infection (84 versus 45), p < 0.001. There was a clear tendency for cases with either infection to locate along major road and rail transport routes. Foci of gonococcal infection were concentrated mainly in the densely populated areas, whereas chlamydial cases were more evenly spread. There was no significant effect of gender or type of STD on the odds ratio for residence in Harrow, single marital status or attendance for test of cure. However, the odds ratios for women having sexual intercourse with a regular partner only or previous STD were 5 (95% CI 2.4 to 10.2), p < 0.001 and 0.3 (95% CI 0.18 to 0.69), p = 0.002 times the odds for men, respectively. The odds ratios for patients with gonococcal infection being employed or having sex with a regular partner only were 0.5 (95% CI 0.27 to 0.98), p = 0.04 and 0.30 (95% CI 0.15 to 0.60), p < 0.001 times the odds for patients with chlamydial infection, respectively. Of the women with gonorrhoea and previous pregnancy, 68% gave a history of abortion compared with 44% of those with chlamydial infection (p = 0.03). CONCLUSION: The identification of foci gonococcal and chlamydial infection and apparent location of these infections along the major transport routes in our health district require further study. That chlamydial infection, unlike gonorrhoea, is evenly distributed irrespective of population concentration and deprivation, suggests urgent need for a comprehensive local effort to control both STDs.     

Chlamydial infections of the urethra in women.

Cervical and endourethral swabs from 360 untreated women attending a sexually transmitted disease (STD) clinic were cultured for Chlamydia trachomatis and other genitourinary pathogens. The patients included contacts of men with non-gonococcal urethritis, women with gonorrhoea, and those in whom symptoms suggestive of urinary tract infection were the main reasons for their attendance. Chlamydial infection of the urethra was less common than, and seldom occurred in the absence of, cervical chlamydial infection; it was frequently silent, producing no signs or symptoms of urethritis. Only 33/96 women with evidence of urethritis gave chlamydia positive urethral swabs, and 14 of them had other concurrent infections of the genitourinary tract. Chlamydia trachomatis thus does not appear to be a major cause of the signs and symptoms of urethritis commonly found in women attending STD clinics, and there seems to be no indication for taking routine urethral swabs to aid in the diagnosis of chlamydial infection in women.     

Factors associated with genital chlamydial and gonococcal infection in males.

BACKGROUND--Predictors of chlamydia and gonorrhoea can be used to increase the cost-effectiveness and acceptability of screening programmes, and allow targeting of control strategies. METHOD--All men attending an STD clinic in 1988-1990 were offered screening for chlamydia and gonorrhoea, and the test results correlated with a wide range of potential predictors using multiple logistic regression. RESULTS--Of 9622 attenders, 7992 (82.3%) were tested over a total of 10,110 episodes for chlamydia and 10,090 episodes for gonorrhoea, yielding 729 (7.2%) chlamydial and 123 (1.2%) gonococcal infections. Having urethral discharge and/or dysuria, being heterosexual, and STD contact, unmarried, uncircumcised, tattooed and not having had an STD previously were independently associated with chlamydial infection. Having urethral discharge and/or dysuria, being Aboriginal, an STD contact, homosexual, uncircumcised, tattooed and having sex outside the state in the past three months, no steady partner in the past three months and multiple partners in the past month were associated with urethral gonococcal infection. Selective screening criteria for gonorrhoea provided 90% of positives, eliminated the need for 58% of tests and resulted in an increased yield ratio of 2.2 whereas the corresponding outcomes for screening criteria for chlamydia were 93% 20% and 1.2 respectively. CONCLUSIONS--The widespread influence of confounding on potential predictors for both gonorrhoea and chlamydia may provide misleading indicators of risk factors by univariate analysis. In the setting studied the benefits of selective screening for gonorrhoea in men would be substantial, whereas satisfactory criteria for selective screening for chlamydia could not be identified.     

Risk factors for gonorrhoea, syphilis, and trichomonas infections among women attending family planning clinics in Nairobi, Kenya.

OBJECTIVE--To identify the risk factors for gonorrhoea, syphilis, and trichomonas infections among low risk women in Nairobi, Kenya. METHOD--In a cross-sectional study, 4,404 women attending two peri-urban family planning clinics between 1989 and 1991 were interviewed using a structured questionnaire and examined for signs of sexually transmitted disease (STD) infection. Cervical cultures for gonorrhoea, PAP smear (including microscopy for trichomonas), RPR and HIV testing were done. RESULTS--Positive cervical cultures for gonorrhoea were found in 3.2% of women, positive syphilis serology in 1.9%, and positive trichomonas microscopy in 5.2%. Genital ulcers were found in 1.9% of women. Although unmarried status and reporting more than one sex partner in the previous year were both significantly associated with each disease in the crude analysis, these associations were attenuated after controlling for each other and for other risk factors. The population attributable risks (PARs) for these factors were low (7-16%) owing to the high proportion of cases who were married and monogamous. The majority of women with microbiological evidence of infection had normal pelvic examinations. Clinical diagnostic algorithms for STDs in this population had a low sensitivity and positive predictive value. Nevertheless, a strong association between HIV seropositivity and STDs was observed. CONCLUSION--The low population attributable risks found in this study suggest that behaviour change messages directed to women, particularly if they are married have a low potential for preventing STDs. The poor performance of clinical diagnostic algorithms illustrates the desirability of testing these algorithms in a variety of populations and reinforces the need for low-cost methods of microbiologic diagnosis if populations with relatively low prevalences of these infections are to be included in programmes to diagnose and treat STDs.     

Chlamydial and gonococcal reinfection among men: a systematic review of data to evaluate the need for retesting

This study aimed to systematically review and describe the evidence on chlamydia and gonorrhoea reinfection among men, and to evaluate the need for retesting recommendations in men. PubMed and STI conference abstract books from January 1995 to October 2006 were searched to identify studies on chlamydia and gonorrhoea reinfection among men using chlamydia and gonorrhoea nucleic acid amplification tests or gonorrhoea culture. Studies were categorised as using either active or passive follow-up methods. The proportions of chlamydial and gonococcal reinfection among men were calculated for each study and summary medians were reported. Repeat chlamydia infection among men had a median reinfection probability of 11.3%. Repeat gonorrhoea infection among men had a median reinfection probability of 7.0%. Studies with active follow-up had moderate rates of chlamydia and gonorrhoea reinfection among men, with respective medians of 10.9% and 7.0%. Studies with passive follow-up had higher proportions of both chlamydia and gonorrhoea reinfections among men, with respective medians of 17.4% and 8.5%. Proportions of chlamydia and gonorrhoea reinfection among men were comparable with those among women. Reinfection among men was strongly associated with previous history of sexually transmitted diseases and younger age, and inconsistently associated with risky sexual behaviour. Substantial repeat chlamydia and gonorrhoea infection rates were found in men comparable with those in women. Retesting recommendations in men are appropriate, given the high rate of reinfection. To optimise retesting guidelines, further research to determine effective retesting methods and establish factors associated with reinfection among men is suggested.     

Urethritis in women attending an STD clinic.

Of an unselected group of 159 women attending a sexually transmitted diseases (STD) clinic 20% (32) had symptoms of urethritis. A positive correlation existed between the finding of more than 10 polymorphonuclear leucocytes (PMNL) per high-power field in the Gram-stained urethral smear and the presence of Neisseria gonorrhoeae, Chlamydia trachomatis, and Trichomonas vaginalis. Conversely, these organisms were rarely isolated if no PMNL were present. Fewer cultures gave positive results for these organisms if micturition had occurred less than four hours before examination. C trachomatis was recovered from the urethra or endocervix in 29/150 (19 . 3%) and from the urethra alone in six women. In contrast, N gonorrhoea was never recovered from the urethra in the absence of endocervical infection. Of the 159 women 10% had bacteriuria due to non-sexually transmissible agents; 50% had asymptomatic bacteriuria. All, however, had other urethral pathogens isolated as well. Thus, sexually transmitted disease agents are highly prevalent in women attending an STD clinic who have signs and symptoms of urethritis. As in non-gonococcal urethritis in men, C trachomatis may be an important cause of urethritis in women.     

Group B streptococci in venereal disease clinic patients.

The isolation rates of group B streptococci for 457 men and 300 women attending a venereal disease clinic were 16-4 and 20-6% respectively. The frequencies were significantly increased by using a selective medium and by taking specimens from the female urethra as well as the cervix. In contrast to gonorrhoea the presence of group B streptococci could not be related to promiscuity. In addition, the isolation of group B streptococci was found to be independent of a concomitant gonococcal infection. This study indicates that group B streptococci have little relation to the clinical signs and symptoms of genital infection, such as dysuria, discharge and inflammatory mucosal reaction.     

Group B streptococci in venereal disease clinic patients.

The isolation rates of group B streptococci for 457 men and 300 women attending a venereal disease clinic were 16-4 and 20-6% respectively. The frequencies were significantly increased by using a selective medium and by taking specimens from the female urethra as well as the cervix. In contrast to gonorrhoea the presence of group B streptococci could not be related to promiscuity. In addition, the isolation of group B streptococci was found to be independent of a concomitant gonococcal infection. This study indicates that group B streptococci have little relation to the clinical signs and symptoms of genital infection, such as dysuria, discharge and inflammatory mucosal reaction.     

Study of STD clinic attenders in England and Wales, 1978. 2. Patterns of diagnosis.

A study of diagnostic patterns in patients attending sexually transmitted disease clinics in England and Wales during 1978 showed that homosexuals contributed 10% of all male cases but 15% of gonococcal infections. In heterosexual and homosexual men only 6% of disease episodes included more than one positive diagnosis compared with 16% in women. One or more diseases occurred concurrently in over 30% of cases of gonorrhoea, trichomoniasis, candidosis, genital herpes, and genital warts in women. Men with multiple episodes of disease contributed a disproportionate number of gonococcal infections but were less likely to have candidosis or genital herpes than patients with only one disease episode. Thus, counting cases treated appears to be an inadequate way of measuring the problems caused by STDS. To enable more rapid identification of the diseases which are the most difficult to control, STD statistics should include the sexual orientation of male patients and differentiate between genuine "new" attenders at clinics and those previously seen.     

Enzyme-linked immunosorbent assay for detecting gonococcal antibodies using two antigenically different gonococcal pili as antigen.

Antibodies to pilar antigens of two gonococcal strains isolated in Rotterdam (6650 and 1443) were detected using enzyme-linked immunosorbent assays (ELISA). Paired sera (the first sample taken at the first examination (D1) and the second 11-22 days later (D2)) from women with and without gonorrhoea attending a sexually transmitted disease (STD) clinic were studied. The sensitivity of the ELISA using gonococcal pili 6650 as antigen (ELISA 6650) was significantly higher than that using gonococcal pili 1443 as antigen (ELISA 1443). The specificity of the two tests differed little. On D1 the sensitivity in women with uncomplicated gonorrhoea was 69% in the ELISA 6650 and 45% in the ELISA 1443; the corresponding values in asymptomatic infected women were 75% and 57% respectively. The agreement (both in positive and in negative results) between the two tests was less than might have been expected (kappa = 0.41).     

Studies on the influence of antigens on the results with the gonococcal complement fixation test in patients with uncomplicated and complicated gonorrhoea.

The gonococcal complement fixation test (GCFT) was investigated with regard to its sensitivity and specificity by testing serum specimens from (a) female patients attending a VD out-patient clinic because of suspected gonorrhoea, (b) patients with a proven, uncomplicated, urogenital gonococcal, infection, (c) patients with disseminated gonococcal infection (DGI). Three different pools of gonococcal (GC) antigens were used which were comprised of GC strains from two different geographical areas. It was found that 39% of the females with culture-proven uncomplicated gonorrhoea had a positive GCFT whereas 10% of the females with negative GC cultures had a positive GCFT. The latter were found to have either a history of gonorrhoea or strong clinical suspicion of recent GC infection. One of the GC antigen pools gave a much lower diagnostic yield than the other two pools in the GCFTs with serum specimens from patients with uncomplicated gonorrhoea. However, no differences were found between the antigen pools in the tests with serum specimens from patients with DGI. These findings indicate the presence of various strain antigens participating in the immune response to complicated as well as uncomplicated GC infections. The results are presented in detail and discussed.     

HIV and other sexually transmitted diseases at a rural hospital in Zimbabwe.

OBJECTIVE--To define the epidemiological characteristics of STD patients attending an outpatient clinic in rural Zimbabwe, to examine the aetiologic agents causing infection and to determine their relationship with HIV infection. SUBJECTS--319 men and 146 women, making a sample of about 7% all patients attending an STD clinic during the 3 month study period. Microbiological data were collected from 104 men and 72 women selected randomly from these. Pregnant women were excluded and patients who had received antibiotics within the previous 14 days were excluded from the microbiology sub-sample. SETTING--An outpatient STD clinic at a District Hospital on a major truck route about 300 km north of the capital, Harare. METHODS--All new patients attending the clinic during a 3 month period were enrolled for clinical and epidemiological investigations using a standard procedure. Specimens for microbiological investigation were taken from every second patient seen on the first three days of each week. RESULTS--The typical patient was male (m:f ratio 2.2) aged 20-29 years (68% patients), not married (56% men) and in paid employment (66% men vs. 27% for the district). In men the most common presenting feature was genital ulceration, while in women, discharges were more common. Genital warts were noted frequently in both sexes. In the sub-sample examined microbiologically, H ducreyi was isolated from 46% ulcers clinically diagnosed as chancroid, and motile spirochaetes were detected in 25% painless ulcers. Neither of these were detected in ulcers in women, but HSV antigen was found as frequently in ulcers from men (19%) as from women (17%). In patients with genital discharges, gonococcal infection occurred in 64% men and 17% women, while T vaginalis was isolated from 39% women and only 8% men. Over 60% gonococcal isolates were PPNG, and 18% showed in vitro resistance to tetracycline. Yeasts, mainly C albicans were isolated from 42% women with a discharge and 25% women with ulcers. In men the presence of yeasts was associated with superficial ulceration and itchiness of the glans. Positive HIV-1 serology was found in 64% patients. There was no statistical association with current genital ulcers, though there was an association with previous STD episodes and particularly with serological evidence of syphilis. Apart from yeasts, there was no association between positive HIV-1 serology and the presence of pathogens in the genital tract. CONCLUSIONS--The high prevalence of HIV-1 antibodies in STD patients in Karoi suggests integration of STD and AIDS control programmes to be a necessity. Since paid employment was a common feature of both STD clinic attendance and HIV-1 seropositivity, these programmes may be effectively directed through the work place.     

Study of STD clinic attenders in England and Wales, 1978. 2. Patterns of diagnosis

A study of diagnostic patterns in patients attending sexually transmitted disease clinics in England and Wales during 1978 showed that homosexuals contributed 10% of all male cases but 15% of gonococcal infections. In heterosexual and homosexual men only 6% of disease episodes included more than one positive diagnosis compared with 16% in women. One or more diseases occurred concurrently in over 30% of cases of gonorrhoea, trichomoniasis, candidosis, genital herpes, and genital warts in women. Men with multiple episodes of disease contributed a disproportionate number of gonococcal infections but were less likely to have candidosis or genital herpes than patients with only one disease episode. Thus, counting cases treated appears to be an inadequate way of measuring the problems caused by STDS. To enable more rapid identification of the diseases which are the most difficult to control, STD statistics should include the sexual orientation of male patients and differentiate between genuine "new" attenders at clinics and those previously seen.     

Quantitative study of Chlamydia trachomatis in genital infection.

Chlamydia trachomatis inclusion counts on inoculated McCoy cell coverslips were used as an index of the degree of infection of the cervix in women and of the urethra in men with urethritis. High inclusion counts were obtained significantly more often from men than from women, from women with cervical ectopy, and from women who had had recent sexual intercourse. Low inclusion counts were significantly more common in men with a past history of gonococcal urethritis. Higher chlamydial isolation rates in women with gonorrhoea and in women taking the contraceptive pill could not be attributed to a greater degree of infection, since inclusion counts were not raised in these patients. There was evidence that strains of C trachomatis might vary in their ability to establish themselves in the genital tract because high counts in men with NGU were associated with high counts in their female consorts and the levels of counts in men were associated with the frequency of chlamydial isolation from their female consorts. The relatively simple technique of inclusion counts in cultures for chlamydia from the genital tract may yield valuable information about the behaviour of different strains of C trachomatis in causing pathological changes, in the transmission of infection between individuals, and in the response to specific chemotherapy.     

Barrier methods of contraception, spermicides, and sexually transmitted diseases: a review.

OBJECTIVE--To understand whether barrier methods of contraception (BMC) and/or spermicides lower the risk of acquiring sexually transmitted disease (STD) and to quantify the protection. DESIGN--Review of published experimental studies, in vitro and in vivo evidence on the issue. SUBJECTS--We reviewed 22 papers that examined the impermeability of BMC in vitro against STD agents or the effect of spermicides, and 60 papers reporting results of epidemiological studies on the risk of STD in users of BMC. RESULTS--There was in vitro evidence that both BMC and spermicides were effective against most sexually transmissible agents. Doubts remain on the effectiveness of BMC and spermicides in normal conditions of use, particularly against human papilloma virus. Natural membrane condoms are not impermeable and pores are seen by electron microscopy. Epidemiological studies show a consistent reduction in the risk for use of condoms against gonococcal (most studies giving relative risk, RR, estimates around 0.4 to 0.6) and HIV infection (RRs between 0.3 and 0.6 in most studies). Spermicides protect women against gonorrhoea and trichomoniasis; their role against other STDs is less clear and there is some indication of an irritative effect on the vaginal mucosa that is likely to be dose-dependent. CONCLUSIONS--A large amount of evidence indicates that BMC reduce the risk of gonorrhoea and HIV transmission, but the results are--at least in quantitative terms--less consistent for other diseases. Implications for individual choices and public health approaches should relate to frequency of exposure and severity of the disease too.     

Epidemiological treatment gonorrhoea and non-specific genital infection in female sexual contacts. Current practices in STD clinics in England and Wales.

In a study to quantify epidemiological treatment given to female contracts for gonorrhoea and non-specific genital infection in STD clinics in England and Wales two-thirds of women treated for gonorrhoea during 1978 were named contacts, a quarter of whom received epidemiological treatment. Only 35% of cases treated in this way were subsequently confirmed microbiologically, but nearly 1000 unconfirmed cases were returned as if they were true cases of gonorrhoea. In view of modern culture techniques and the low default rates found in this study, there seems to be little justification for the use of epidemiological treatment for gonorrhoea. Of women who gave a history of exposure to non-specific urethritis, 86% received epidemiological treatment. The variation in diagnostic and notification criteria for non-specific genital infection results in virtually worthless statistics for female cases treated.     

Antibodies to gonococcal pili in women with asymptomatic gonorrhoea. Diagnostic value of the ELISA for testing women attending an STD clinic.

The diagnostic efficacy of an enzyme-linked immunosorbent assay (ELISA) using gonococcal pili 6650 as antigen was studied in asymptomatic women attending an STD clinic. Of the 182 women studied, gonorrhoea was diagnosed in 29%. The value of the ELISA was calculated on the basis of four arbitrary cut-off points in the test. The best predictive values for a positive result (PV(+)) were obtained at an absorbance value of A greater than or equal to 1.15 and A greater than or equal to 1.30 and that for a negative result at A greater than or equal to 0.85. When patients with a history of gonorrhoea were excluded, the PV(+) rose only at A greater than or equal to 1.15 (not at A greater than or equal to 1.30) and the PV(-) rose slightly. To be of use in the diagnosis of gonorrhoea in asymptomatic patients the ELISA should be used as follows: the result is positive at A greater than or equal to 1.15 and negative at A less than 0.85, the PV(+) then being 0.52 and the PV(-) 0.85. Whenever sera give a result between A = 0.85 and A = 1.15, the test should be repeated.     

Characterisation of Neisseria gonorrhoeae in semen during urethral infection in men.

OBJECTIVE: To determine the number of Neisseria gonorrhoeae organisms in urine and semen in men with gonococcal urethritis, and to compare selected phenotypic characteristics of organisms harvested from the urethra and semen. DESIGN: Samples from two groups of subjects were examined. Patients with symptomatic urethritis receiving treatment at an STD clinic, as well as six subjects with experimental urethritis. Semen and urine specimens were obtained after the urethral exudate was sampled. RESULTS: Using quantitative cultures, we found an average of 6 x 10(6) gonococci in urine or semen of 17 men with symptomatic urethritis seeking treatment at an STD clinic, and 2 x 10(4) gonococci in secretions of six male subjects with early experimental infection. Gonococcal outer membrane opacity (Opa) proteins and lipo-oligosaccharide (LOS) recovered from urine and semen of these subjects were very similar. CONCLUSIONS: Men with symptomatic gonorrhoea excrete a large number of gonococci in semen which is not affected by the duration of symptoms. The similar phenotype of organisms in urine and semen suggests the bacteria come from the same compartment. These data help to explain the efficiency of gonococcal transmission from men to their partners, and identify an appropriate target for a preventative vaccine or immunotherapy designed to reduce the inoculum in infected patients.