Declining prevalence of chlamydial infection among adolescent girls

Screening for Chlamydia trachomatis infection among infertile women in Saudi Arabia

BACKGROUND

Chlamydia trachomatis infection is a worldwide-distributed sexually transmitted infection that may lead to infertility.

OBJECTIVES

This study aims to report the prevalence of Chlamydia trachomatis infection among infertile women in Saudi Arabia.

PATIENTS AND METHODS

A community-based study carried out at the obstetrics and gynecology clinic at Jazan General Hospital, Saudi Arabia. The study group included 640 Saudi infertile women who were aged between 18 and 40 years and who attended the gynecology clinic for infertility examination throughout 1 year of study (from July 1, 2011 to June 30, 2012). The randomized control group included 100 Saudi fertile women who attended the obstetrics clinic for routine antenatal care. All recruited women were screened for chlamydia infection by enzyme-linked immunosorbent assay (ELISA) for detection of serum-specific antibodies and then retested by the McCoy cell culture technique.

RESULTS

The prevalence of Chlamydia trachomatis infection among infertile women was high, at 15.0%. The rate of chlamydia infection detected by ELISA was 9.84%, and it was 12.03% by the culture method (P = 0.2443).

CONCLUSION

The high prevalence of Chlamydia trachomatis infection among Saudi infertile women demands a national screening program for early detection among infertile couples. ELISA is available as a simple screening test alternative to the culture method.

Efficacy of a motivational behavioral intervention to promote chlamydia and gonorrhea screening in young women: a randomized controlled trial

BACKGROUND

Seeking screening and treatment for chlamydia (CT) and gonorrhea (GC) by young women is critical to reduction of asymptomatic cervicitis and its complications.

OBJECTIVES

To evaluate the efficacy of a client-centered motivational behavioral intervention (MBI), to promote seeking of sexually tranmitted infection (STI) checkups by young women.

METHODS

Three hundred seventy-six of 770 eligible sexually active, nonpregnant, English-speaking women (mean age 18.5 years) were recruited from an urban reproductive health clinic and randomized to two groups: intervention plus standard care (MBI) or standard care alone (SC). MBI (two sessions plus booster) was based on the Transtheoretical Model of Change and employed motivational interviewing. Outcome measures monitored for 12 months included: client-initiated clinic visits for STI checkups in response to seven high-risk sexual behaviors by self-report (primary), consistent condom use, number of CT and GC episodes, and movement along the stages of change obtained at baseline and 6- and 12-month follow-up assessments (secondary). Analyses included chi-square, logistic regression, and generalized estimating equations.

RESULTS

At baseline, more than 70% endorsed the action stage of change for seeking STI checkups for three of seven high-risk sexual behaviors. No significant differences were noted between the two groups for the primary or secondary outcomes. Across groups, having multiple partners and being pregnant or thinking one might be pregnant were associated with STI checkups.

CONCLUSIONS

This is the first known client-centered clinical trial to promote STI screening. Risk-taking and health-seeking behaviors are complex and interrelated with STI and pregnancy concerns. The intervention may have an effect if it is targeted to women in a less medically connected community-based sample.

Use of an adaptation of a commercially available PCR assay aimed at diagnosis of chlamydia and gonorrhea to detect Trichomonas vaginalis in urogenital specimens

Trichomonas vaginalis PCR using reagents from a commercially available assay for Chlamydia trachomatis and Neisseria gonorrhoeae was evaluated for detection of infection in women and men attending a sexually transmitted disease clinic. Evaluations included three primer sets, endocervical swabs, vaginal swabs and urine, and various storage conditions. The TVK3/TVK7 primer set was optimal in our hands with sensitivities ranging from 69.5 to 96.8%. In all comparisons, T. vaginalis PCR performed better than routine diagnostics using microscopy for women and culture for men (P > 0.05). The assay performed well for all sample types tested, and vaginal swabs were stable for up to 7 days at ambient temperature. Using samples prepared for, and reagents from, the C. trachomatis-N. gonorrhoeae PCR assay allowed incorporation of T. vaginalis PCR diagnosis into routine clinical testing.

Diagnosis of sexually transmitted infections (STI) using self-collected non-invasive specimens

Paramount in control of transmission of sexually transmitted infections (STIs) is their prompt recognition and appropriate treatment. In countries where definitive diagnoses are difficult, a 'syndromic approach' to management of STIs is recommended and practiced, yet many STIs have common symptoms or are asymptomatic and therefore go undetected and untreated. This is of particular concern with the recognition that HIV transmission is increased with co-existent STIs: the attributable risk for each STI varying with the prevalence within a particular population. Hence, HIV public health prevention approaches must include STI preventative strategies to be effective. Even then, microbiological screening is incorporated into STI control strategies; lack of access to appropriate services (especially in rural and remote areas), reluctance of at-risk populations to attend for treatment, fear of invasive genital examinations, and lower sensitivities of conventional diagnostic assays reduces the effectiveness of such programmes. Therefore, accurate, cost-effective, reliable diagnostic assays (preferably those which can be used in the field) are needed to impact on the incidence of the various STIs, as well as HIV. With the advent of molecular technologies, including target and signal amplification methods, diagnoses of STIs have been revolutionised and allow the use of non or minimally invasive sampling techniques, some of which are self-collected by the patient, e.g. first-void urine, cervico-vaginal lavage, low vaginal swabs, and tampons. Most studies evaluating such self-sampling with molecular diagnostic techniques have demonstrated an equivalent or superior detection of STIs as compared to conventional sampling and detection methods. These sampling methods can also be used to determine prevalence of STIs in various populations, but particularly those with difficult access to medical care. In this article, the utility of self-sampling collection devices for detection of various STIs, particularly in women, is reviewed as one step towards formulating appropriate strategies in control of STIs, and which are especially suited for remote areas.

Chlamydia trachomatis infections in neonates and young children

In 1911, Lindner and colleagues identified intracytoplasmic inclusions in infants with a nongonococcal form of ophthalmia neonatorum called inclusion conjunctivitis of the newborn (ICN). Mothers of affected infants were found to have inclusions in their cervical epithelial cells, fathers of such infants had inclusions in their urethral cells, and the epidemiology of sexually transmitted chlamydial infections was revealed. Fifty years later, chlamydial isolation procedures were developed, and studies again demonstrated Chlamydia trachomatis as an etiology of ICN and the female birth canal as the reservoir. In the late 1970s, a report by Beem and Saxon described respiratory tract colonization and a distinct pneumonia syndrome in infected infants. Genital chlamydial infection is recognized as the world's most common sexually transmitted disease, with estimates of greater than 4 million new infections occurring annually in the United States. Although most C. trachomatis infections in men and women are asymptomatic, infection can lead to severe reproductive complications in women. The high prevalence in women of child-bearing age results in exposure of an estimated 100,000 neonates in the United States annually. Many of these infants develop conjunctivitis, pneumonia, or both in the first few months of life. Clinical features, diagnosis, treatment, and approaches to prevention of conjunctivitis and pneumonia in the newborn and young infant are reviewed here. Appropriate testing for chlamydial infection in a pediatric victim of sexual assault and the implications of identifying C. trachomatis in suspected cases of childhood sexual abuse also are reviewed.

Chlamydia and gonorrhea screening in asymptomatic young women

BACKGROUND

Adolescent and young adult minority women are at high risk for chlamydia (CT) and gonorrhea (NGC) cervical infections, which are significant causes of pelvic inflammatory disease, impaired fertility, ectopic pregnancy and chronic pain. The purpose of this article is to review among young women in the United States: (1) the epidemiology of CT and NGC cervical infection and their medical complications; (2) current public health recommendations to promote asymptomatic CT and NGC screening; (3) current screening practices and challenges of implementing public health recommendations; (4) testing and cost issues; and (5) future directions in promoting asymptomatic CT and NGC screening.

METHODS

We conducted a MEDLINE search for articles published over the last two decades relating to CT and NGC screening in young women and then systematically reviewed all relevant articles.

RESULTS

The data indicate that CT and NGC infection are geographically widespread in the U.S. and asymptomatic infection is highly prevalent among economically disadvantaged young females. Public health recommendations promoting CT and NGC screening in asymptomatic young women are directed to both health care providers and clients. However, strategies to promote screening efforts have been primarily directed toward health care providers; there are no published studies on client-initiated screening strategies. Challenges of implementing public health recommendations and future directions for CT and NGC screening are discussed.

CONCLUSIONS

Young sexually active women continue to be at high risk for CT and NGC infection. The data indicate that implementation of health provider-based and client-initiated screening in private and public health care settings is a challenge. However, there is a great need to develop strategies to understand and promote client-initiated screening.

Developments in the screening for Chlamydia trachomatis: a review

Many studies have evaluated selective screening criteria for women in various settings. Most have concluded and all guidelines recommend that all women aged < 25 be screened yearly for C. trachomatis infection. Behavioral criteria, such as the number of sex partners, new or more than one sex partners, and previous infection, also can serve as criteria for screening women aged > 25. Because re-infection rates are high and occur within a few months, complications may be reduced further if partners are treated and women rescreened 4 to 6 months after initial infection. Revised recommendations for C. trachomatis screening programs have stated that more frequent screening may be considered among women < 20 and those with recent infection. Screening in nontraditional settings and careful evaluation of local prevalence and risk factor information should be encouraged. Private providers and emergency room providers should discuss screening recommendations and adopt a C. trachomatis screening policy for the population they serve. The HEDIS measure should serve to encourage at least annual screening of 15- to 25-year-old sexually active females through providers linked to managed care organizations. In general, high yields (ie, percentage of tests that are positive) in nontraditional settings and enhanced feasibility and acceptability of urine-based tests may encourage further innovative approaches to reach and screen populations at risk. Several issues remain to be addressed to increase the effectiveness of screening efforts. If more sensitive amplification tests are used widely, more infected persons will be identified and treated, and transmission patterns may change, particularly if partner treatment also occurs. Current screening criteria should continue to be re-evaluated. An important issue that affects testing methods includes the possible need for confirmation testing when using NAATs if the prevalence of C. trachomatis is less than 2%. If the sensitivity of an NAAT is 85% and specificity is 99%, in a hypothetical population of 10,000 with a prevalence of 2%, the positive predictive value is 170/268 (63%). A second important issue affecting testing methods and feasibility of using NAATs for screening large numbers of individuals is the pooling of urine specimens, which has been evaluated in several studies and found to be very effective for reducing costs. A research issue for pooling is the determination of the most cost-effective prevalence levels for pooling. An additional research question is in which populations should a NAAT be used for detection of C. trachomatis and N. gonorrhoeae. There are no recommendations for the routine screening of men because of the paucity of data showing that this strategy can reduce sequelae. The CDC is conducting a multisite study to examine the feasibility, acceptability, and usefulness of screening of asymptomatic men. There are a few studies have determining cost-effective prevalence threshold levels, particularly with NAATs. A recently developed decision analysis model by CDC designed to maximize the effectiveness of screening strategies for C. trachomatis infections may be useful for decision makers. It is intended to serve as an easy and flexible tool to determine cost effectiveness at a local level and takes into account positivity rates and test performance characteristics (SOCRATES). It is unclear if recurrent infection is caused by true re-infection by the same or a different partner or recurrence of initial infection. Recurrence may be caused by persistence of C. trachomatis or antibiotic resistance. This distinction is of scientific interest because the appropriate intervention differs (eg, identification of risk factors for the former and microbiologic investigations for the latter). Effective partner management and retesting are critical to reducing sequelae of C. trachomatis infection. Screening for C. trachomatis infection remains an essential component of C. trachomatis control. It is cost effective, most infections are asymptomatic, and symptom-based health care seeking and testing identify few of those infected. The likelihood that opportunities for screening are missed is high particularly in non-STD clinic settings. Local studies using NAATs to determine C. trachomatis prevalence and risk factors are helpful to health care providers so they can make evidence-based decisions on who to screen. The use of nontraditional, non-clinic-based test settings should be explored further. We have focused on summarizing the medical evidence regarding recommendations for screening for C. trachomatis. High-risk populations for C. trachomatis infection may overlap with populations for other STDs, and comprehensive STD prevention programs that involve a range of STD service providers are needed to successfully reduce the STD-related health burden in the population.

Demonstration of declining community prevalence of Chlamydia trachomatis infection using sentinel surveillance

BACKGROUND

Chlamydia trachomatis infection rates in Alabama increased dramatically from 1996 to 1998, due in part to expanded screening. Detection of prevalent infection through increased testing could mask timely detection of the impact of screening programs on community prevalence.

GOAL

The goal of the study was to evaluate the temporal trend in prevalence among women aged 15 to 34 years attending reproductive healthcare clinics in Birmingham, Alabama.

STUDY DESIGN

Between 1995 and 1998, systematic screening of the first 60 women presenting each month to each of six participating clinics was performed with urine-based testing for chlamydia.

RESULTS

In contrast to the 218% increase in chlamydia prevalence detected through passive surveillance, during the study period surveillance in sentinel sites revealed that first-visit chlamydia prevalence declined from 12.8% to 8.6%.

CONCLUSIONS

Sentinel site surveillance served as a valuable adjunct to passive surveillance for determining the true trend of chlamydia prevalence during the hyperendemic phase of a local epidemic.

Epidemiology of female genital Chlamydia trachomatis infections

The World Health Organization (WHO) has estimated that 92 million new cases of C. trachomatis (Chlamydia trachomatis) infection occur each year. This chapter focuses on the epidemiology of C. trachomatis infection, including the prevalence of infection in high- and low-risk groups, the incidence of infection, and data on secular trends. The evidence on the transmission of infection is reviewed. Risk factors for C. trachomatis infection in women are discussed. The adverse sequelae associated with C. trachomatis infection are described. Areas requiring further research are highlighted.

Clinic-based service programs for increasing responsible sexual behavior

Three general classes of clinic-based programs to increase responsible sexual behavior are considered: (a) clinic-based educational/counseling programs, (b) school clinic-based condom distribution programs, and (c) clinic-based STD/HIV screening programs. Consistent condom use may double in response to clinic-based counseling. However, consistent use seldom exceeds 50% of coital exposures. Extensive and personalized counseling interventions reduce incident sexually transmitted infections by 5% to 10%. Increases in responsible sexual behavior following school-based condom distribution programs is reported in some but not in all studies. Screening programs for sexually transmitted infections are associated with decreases in rates of some infections. STD/HIV screening should be considered an important aspect of healthy sexuality and an adjunct to other counseling efforts.

Predictors of Chlamydia trachomatis infection among women attending rural Midwest family planning clinics

Objective: To determine predictors of Chlamydia trachomatis infection among women 14–24 years of age attending family planning clinics throughout a rural Midwestern state.

Methods: The study population included 16 756 women between the ages of 14 and 24 years attending family planning clinics for annual examinations throughout the state of Iowa in 1997. All women under 25 years of age having annual exams were tested for C. trachomatis during the visit. At the time of exam, both behavioral and demographic data were collected on all women participating in the study.

Results: The majority of women in the study (96%) reported no symptoms of chlamydia. Only 2.5% of all women had a positive test result. In the multivariate model, the odds ratios were significantly increased among the youngest age (14–17 years; OR = 2.2), those with mucopurulent cervicitis (OR = 3.4), cervical friability (OR = 2.2), symptomatic for infection (OR = 1.8), risk history (OR = 1.6), and black race (OR = 1.2) and predictive of a C. trachomatis infection.

Conclusions: Risk factors predictive of C. trachomatis infection among younger aged women attending family planning clinics in a Midwest rural population are consistent with predictors of infection among women attending family planning clinics across theUnited States. The overall findings suggest the importance of developing screening guidelines as a means of lowering chlamydia rates. This may be a particularly difficult task in light of the low rate of symptoms that would lead a woman to seek medical care, even in younger age women who are at higher risk. In addition, screening guidelines would be more difficult to implement in a rural setting.

Urine-based screening for Chlamydia trachomatis in men attending sexually transmitted disease clinics

BACKGROUND

Nucleic acid-amplified tests for Chlamydia trachomatis are accurate but costly. Screening strategies for asymptomatic men are needed.

GOAL

To assess C trachomatis screening strategies for asymptomatic males.

STUDY DESIGN

Men attending a sexually transmitted disease clinic were tested for C trachomatis with ligase chain reaction and culture, and for urethral inflammation with urine leukocyte esterase and urethral Gram stain.

RESULTS

C trachomatis prevalence was 5.5% among 1,625 asymptomatic men. Ligase chain reaction increased detection by 49% among men without urethral inflammation. An age of younger than 25 years and urethral inflammation were associated with positive ligase chain reaction results. The negative predictive value of urine leukocyte esterase was highest among older men, but urethral Gram stain was equally sensitive in predicting infection regardless of age. An age of younger than 30 years or urethral inflammation identified the highest proportion of infections (92%) and reduced the percentage of men screened by 43%.

CONCLUSIONS

Urine ligase chain reaction increased C trachomatis detection, particularly among men without urethral inflammation. Testing all asymptomatic men younger than 30 years is optimal, whereas negative urine leukocyte esterase or urethral Gram stain results in men 30 years or older support no testing.

Screening for chlamydial infection

OBJECTIVES

To examine data on the effectiveness of screening for chlamydial infection by a physician or other health care professional. Specifically, we examine the evidence that early treatment of chlamydial infection improves health outcomes, as well as evidence of the effectiveness of screening strategies in nonpregnant women, pregnant women, and men, and the accuracy of tests used for screening. This review updates the literature since the last recommendation of the U.S. Preventive Services Task Force published in 1996.

SEARCH STRATEGY

We searched the topic of chlamydia in the MEDLINE, HealthSTAR, and Cochrane Library databases from January 1994 to July 2000, supplemented by reference lists of relevant articles and from experts in the field. Articles published prior to 1994 and research abstracts were cited if particularly important to the key questions or to the interpretation of included articles.

SELECTION CRITERIA

A single reader reviewed all English abstracts. Articles were selected for full review if they were about Chlamydia trachomatis genitourinary infections in nonpregnant women, pregnant women, or men and were relevant to key questions in the analytic framework. Investigators read the full-text version of the retrieved articles and applied additional eligibility criteria. For all topics, we excluded articles if they did not provide sufficient information to determine the methods for selecting subjects and for analyzing data.

DATA COLLECTION AND ANALYSIS

We systematically reviewed three types of studies about screening in nonpregnant women that relate to three key questions: (1) studies about the effectiveness of screening programs in reducing prevalence rates of infection, (2) studies about risk factors for chlamydial infection in women, and (3) studies about chlamydial screening tests in women. Our search found too few studies on pregnant women to systematically review, although pertinent studies are described. We systematically reviewed two types of studies about screening in men: (1) studies about prevalence rates and risk factors for chlamydial infection in men and (2) studies about chlamydial screening tests in men.

MAIN RESULTS

Nonpregnant women. The results of a randomized controlled trial conducted in a large health maintenance organization indicate that screening women selected by a set of risk factors reduces the incidence of pelvic inflammatory disease (PID) over a 1-year period. Changes in population prevalence rates have not been well documented because few studies have employed a representative population sample. Age continues to be the best predictor of chlamydial infection in women, with most studies evaluating cut-offs at age younger than 25 years. Other risk factors may be useful predictors, but these are likely to be population specific. To determine the accuracy of screening tests for women, we retrieved and critically reviewed 34 articles on test performance. Results indicate that endocervical swab specimens and first-void urine specimens have similar performance when using DNA amplification tests and have better sensitivity than endocervical culture. Recurrent chlamydial infections in women have been associated with increased risks for PID and ectopic pregnancies. Pregnant women. The Second Task Force recommendations for screening pregnant women were based on two major studies demonstrating improved pregnancy outcomes following treatment of chlamydial infection. We identified no recent studies on this topic in our literature search. Very few studies describe risk factors for chlamydial infection in pregnant women. Nonculture testing techniques appear to perform well in pregnant women, although studies are limited. Men. No studies described the effectiveness of screening or early treatment for men in reducing transmission to women or in preventing acute infections or complications in men. Studies of prevalence rates and risk factors for chlamydial infection in men are limited. Age lower than 25 years is the strongest known risk factor cited so far. Results of urethral swab specimens compared to first-void urine specimens were similar for DNA amplification tests. DNA amplification techniques are more sensitive than culture.

CONCLUSIONS

Screening women for Chlamydia trachomatis reduces the incidence of PID, and it is associated with reductions in prevalence of infection in uncontrolled studies. No studies were found to determine whether screening asymptomatic men would reduce transmission or prevent acute infections or complications. Age is the strongest risk factor for men and women. A variety of tests can detect chlamydial infection with acceptable sensitivity and specificity, including new DNA amplification tests that use either endocervical swabs in women, urethral swabs in men, or first-void urine specimens from men and women.

Multicenter evaluation of the BDProbeTec ET System for detection of Chlamydia trachomatis and Neisseria gonorrhoeae in urine specimens, female endocervical swabs, and male urethral swabs

The performance of the Becton Dickinson BDProbe Tec ET System Chlamydia trachomatis and Neisseria gonorrhoeae Amplified DNA Assays (BD Biosciences, Sparks, Md.) was evaluated in a multicenter study. Specimens were collected from 2,109 men and women, with or without symptoms, attending sexually transmitted disease, family planning, and obstetrics and gynecology clinics. Both swab and urine samples were collected, and the results obtained from 4,131 specimens were compared to those from culture and the LCx nucleic acid amplification test (Abbott Industries, Abbott Park, Ill.). PCR and cytospin of the culture transport medium with chlamydia direct fluorescent antibody staining were used to adjudicate chlamydia culture-negative results. Sensitivity and specificity were calculated both with and without use of the amplification control (AC), with little apparent difference in the results. Without the AC result, sensitivity for C. trachomatis and N. gonorrhoeae were 92.8 and 96.6%, respectively, for cervical swabs and 80.5 and 84.9% for urine from women. C. trachomatis and N. gonorrhoeae sensitivities were 92.5 and 98.5%, respectively, for male urethral swabs and 93.1 and 97.9% for urine from men. This amplified DNA system for simultaneous detection of chlamydial and gonococcal infections demonstrated superior sensitivity compared to chlamydia culture and has performance characteristics comparable to those of other commercially available nucleic acid-based assays for these organisms.

Home sampling versus conventional swab sampling for screening of Chlamydia trachomatis in women: a cluster-randomized 1-year follow-up study

We compared the efficacy of a screening program for urogenital Chlamydia trachomatis infections based on home sampling with that of a screening program based on conventional swab sampling performed at a physician's office. Female subjects, comprising students at 17 high schools in the county of Aarhus, Denmark, were divided into a study group (tested by home sampling) and a control group (tested in a physician's office). We assessed the number of new infections and the number of subjects who reported being treated for pelvic inflammatory disease (PID) at 1 year of follow-up; 443 (51.1%) of 867 women in the intervention group and 487 (58.5%) of 833 women in the control group were available for follow-up. Thirteen (2.9%) and 32 (6.6%) new infections were identified in the intervention group and the control group, respectively (Wilcoxon exact value, P=.026). Nine (2.1%) women in the intervention group and 20 (4.2%) in the control group reported being treated for PID (P=.045), indicating that a screening strategy involving home sampling is associated with a lower prevalence of C. trachomatis and a lower proportion of reported cases of PID.

Participation in a school-based sexually transmitted disease screening program

BACKGROUND

A school-based chlamydia screening program was offered repeatedly in three Louisiana public high schools in an effort to expand sexually transmitted disease screening services for adolescents.

GOAL

To describe participation of a fixed cohort of students to elucidate the impact of screening on chlamydia prevalence.

STUDY DESIGN

Five opportunities for chlamydia testing were offered in 3 schools during 3 school years (1995-1996, 1996-1997, 1997-1998). Only students with parental consent could be tested. Students consistently enrolled during the 3 years (n = 1475) were included in this analysis.

RESULTS

During the 3 school years, parental consent was cumulatively obtained for 1443 students (97.8%), and 1305 students (88.5%) were tested at least once. Of those tested, 81.1% tested more than once. The prevalence of Chlamydia trachomatis infection at first test among students who tested more than once was 1.8% for males and 7.7% for females. Among students tested only once, 6.2% of males and 12.7% of females had chlamydial infection. Among students tested more than once, no significant difference in C. trachomatis prevalence was associated with repeat screenings. Incidence rates per 1000 person-months were 4.3 (2.2, males; 7.1, females; P < 0.0001). Reinfections explained only 5.6% of all incident cases.

CONCLUSION

The documented high response from both parents and students to this school-based chlamydia screening program offers great promise for sexually transmitted disease control among adolescents. Overall, C. trachomatis prevalence was two times higher among students testing only once than among those testing more than once. Routine and continued availability of school-based chlamydia screening programs can potentially reduce the burden of disease among adolescents.

College health needs to participate in the national STD debate

We have a window of opportunity in which events are coming together, and we in ACHA can make a significant impact on STDs/STIs. College health professionals can choose to become actively involved or we can be bystanders. Our population, our tradition, and our moral imperatives all urge us to become engaged at all levels. We work with one of the most highly educated of all groups--a group that also shows some of the highest rates of risky behaviour--and we should be able to demonstrate the highest levels of successful intervention.

Trend in Chlamydia trachomatis infection among pregnant women in the past ten years in Japan: significance of Chlamydia trachomatis seroprevalence

BACKGROUND AND OBJECTIVES

Chlamydia trachomatis infection is believed to be the most common bacterial sexually transmitted disease (STD) in industrialized countries. The objective of the current study was to assess the recent trend in the prevalence of C. trachomatis in Japan.

GOAL OF THIS STUDY

To determine the trend in the seroprevalence for C. trachomatis among pregnant women in Nagasaki, Japan, during the past 10 years.

STUDY DESIGN

The seroprevalence for C. trachomatis of 9,652 pregnant women of various ages screened in 1996 and 1997 was compared with those of 275 and 297 stocked samples from 1987 and 1992, respectively. Serum antibodies to C. trachomatis were detected by the enzyme immunoassay. Prospective samples of 33 seropositive cases were also analyzed to determine kinetics of the serum antibody titer.

RESULTS

The seroprevalence has decreased in all age groups during the last 10 years. More than 70% of seropositive cases converted to be seronegative within 10 years.

CONCLUSION

The prevalence of C. trachomatis has been decreasing among Japanese pregnant women.

Chlamydia trachomatis infections in female military recruits

BACKGROUND

Asymptomatic genital Chlamydia trachomatis infections in women can lead to pelvic inflammatory disease, infertility, and ectopic pregnancy. To design a chlamydia-control program, we conducted a large survey of women in the U.S. military.

METHODS

From January 1996 through December 1997, urine samples from 13,204 new female U.S. Army recruits from 50 states were screened by ligase chain reaction for C. trachomatis infection. Information on potential risk factors was obtained by questionnaire. With multivariate analysis, we identified criteria for a screening program.

RESULTS

The overall prevalence of chlamydial infection was 9.2 percent, with a peak of 12.2 percent among the 17-year-old recruits. The prevalence was 15 percent or more among the recruits from five southern states. The following risk factors were independently associated with chlamydial infection: having ever had vaginal sex (odds ratio for infection, 5.9), being 25 years of age or less (odds ratio, 3.0), being black (odds ratio, 3.4), having had more than one sex partner in the previous 90 days (odds ratio, 1.4), having had a new partner in the previous 90 days (odds ratio, 1.3), having had a partner in the previous 90 days who did not always use condoms (odds ratio, 1.4), and having ever had a sexually transmitted disease (odds ratio, 1.2). A screening program for subjects 25 years of age or less (87.9 percent of our sample) would have identified 95.3 percent of the infected women.

CONCLUSIONS

Among female military recruits, the prevalence of chlamydial infection is high. A control program that screens female recruits who are 25 years old or younger with urine DNA-amplification assays has the potential to reduce infection, transmission, and the sequelae of chlamydial infection.

Genital chlamydial disease in an urban, primarily Hispanic, family planning clinic

BACKGROUND AND OBJECTIVES

Although chlamydia is a well-studied disease, little is known about the rates of genital chlamydial disease among female Hispanics in urban family planning clinics.

GOALS

To determine the prevalence of women with chlamydia in two clinic populations during 1994. We also sought to describe previously identified and novel risk factors for chlamydial disease in this unique population.

STUDY DESIGN

We conducted a retrospective case-control analysis in two community clinics in the Washington Heights section of New York City.

RESULTS

In 1994, 4,190 screening tests were done for Chlamydia trachomatis in these clinics, and the prevalence of positive tests was 5.4% (227/4,190). The mean age of the women screened was 19.2 years and most were of Hispanic origin (76%), students (51%), and received Medicaid (61%). Risk factors found to be associated with C. trachomatis infection included young age; earlier age at first coitus; pregnancy at the time of chlamydia screening; concurrent gonorrheal infection; and the clinical findings of cervical abnormalities, vaginal discharge, and adnexal tenderness. Hormonal contraception appeared to be protective against chlamydial infection (odds ratio, 0.36%; confidence interval, 0.17-0.77).

CONCLUSION

Sexually transmitted diseases were common in our population because 5.4% of the women screened had chlamydial infection and 1.5% had concurrent gonorrheal infection. Our study confirmed risk factors established in other populations. These data support the need for enhanced screening efforts for chlamydia to decrease the prevalence of disease in our population.

Sexually active adolescents and young adults: a high-risk group for Chlamydia trachomatis infection

BACKGROUND

The importance of travel as a risk factor for Chlamydia trachomatis infection was evaluated among a series of young people consecutively tested.

METHODS

We studied 130 sexually active young subjects, aged 14-25 years, all living in the Rome, Italy, urban area. Ninety-eight females and 32 males attended hospital-based clinics or were the partners of an infected female. About half of these subjects had traveled abroad either for pleasure or for work, mostly to Europe, but also to North America or to Asia, where they admitted to having had casual sex. We used two "gold standard" methods to diagnose infection with C. trachomatis: culture on McCoy cells grown in shell vial, and direct immunofluorescence with monoclonal antibodies. Subjects were considered infected when at least one test was positive.

RESULTS

Thirty-nine of 130 (30%) subjects were asymptomatic, and 27/130 (20.8%) subjects were infected with Chlamydia trachomatis, of whom 6/25 (24%) asymptomatic females and 3/14 (21.4%) asymptomatic males were infected. Among teen-aged (ages 14-19) youngsters with more than one sex partner, international travel was an additional significant risk factor for C. trachomatis infection (p<.02; OR 20; 95% CI 1.47-40%). Urethritis/cystitis and vaginal pathology/discharge were the prevalent manifestations of illness among the females, while urethritis was the only clinical condition found in the males.

CONCLUSION

In a series of young subjects, travel abroad, sex with more than one partner, and teen age, combined together, were significant risk factors for the acquisition of Chlamydia trachomatis genitourinary infection.

Detection of Chlamydia trachomatis cervical infection by urine tests among adolescents clinics

PURPOSE

To compare urine ligase and polymerase chain reaction (LCR, PCR) tests for diagnosis of Chlamydia trachomatis cervical infection with PCR and nucleic acid probe (GPA) on cervical specimens in adolescents, as well as risk factors for C. trachomatis infection and prevalence of infection at enrollment.

METHODS

Urine and cervical specimens were collected from women aged 13-20 years attending adolescent clinics, and interviews were administered. Urine specimens were tested by PCR and LCR, and cervical specimens by GPA and PCR. Prevalence rates of C. trachomatis infection and gonorrhea were compared by demographic, behavioral, and clinical risk factors.

RESULTS

Of 415 women tested, 86 (20.7%) were infected with C. trachomatis as indicated by positive cervical PCR results. A higher prevalence of C. trachomatis infection was seen among adolescents who douched monthly or more frequently, or had gonorrhea; prevalence declined from 25.8% in the first 7 months to 16.3% in the last 14 months of the study (p = .017). A statistically significant protective effect for reported condom use was not observed. Sensitivity of urine PCR was 89.5% and specificity was 100% relative to cervical PCR, compared to 84.9% and 99.4% (urine LCR) and 65.4% and 98.0% (cervical GPA). Sensitivity of urine PCR was higher in women with discharge; urine LCR sensitivity was higher in women < 19 years of age.

CONCLUSIONS

Polymerase chain reaction and LCR assays on urine specimens were sensitive, specific, and noninvasive tests in this population of adolescents with high C. trachomatis infection prevalence. Chlamydia trachomatis infection was associated with douching monthly or more frequently. Prevalence of infection declined over the period during which the study was conducted.