Arcari, Christine M. PhD, MPH*; Gaydos, Joel C. MD, MPH‡; Howell, M Renee PhD†; McKee, Kelly T. MD, MPH†; Gaydos, Charlotte A. DrPH, MS, MPH§
CHLAMYDIA TRACHOMATIS AND Neisseria gonorrhoeae are the leading reportable sexually transmitted diseases (STDs) in the United States.1,2 Although chlamydia and gonorrhea infections can be easily diagnosed, treated, and cured, undetected and untreated infections lead to severe and costly health problems such as pelvic inflammatory disease (PID), ectopic pregnancy, and infertility in females, and testicular and prostate infections and infertility in males.3 In 1994, the combined direct and indirect cost of chlamydia and gonorrhea infections in the United States was estimated to be $3 billion.4 These infections disproportionately impact young people; approximately 75% of all reported chlamydia and gonorrhea infections occur in persons aged 15 to 24 years.1 Detection and treatment of chlamydia and gonorrhea infections are important to prevent future health complications and to reduce transmission to uninfected partners.
High rates of chlamydia and gonorrhea have been documented in the U.S. military.5–10 A comparison of STD rates between a military population and a civilian population showed that the incidence of chlamydia and gonorrhea among soldiers remained higher overall than comparable state and national rates, even after adjustment for age and race/ethnicity.5 A study by Cecil et al. of nonhealth-care-seeking male Army recruits found C. trachomatis infections in 5.3% and N. gonorrhoeae infections in 0.6%.8 Shafer et al., in their study in a nonclinic-based sample of young male, deployed military personnel, identified 4.1% with chlamydia infections but none with gonorrhea.9 A study of the causes of urethritis in 400 male soldiers found 35% positive for C. trachomatis and 36% positive for N. gonorrhoeae.10
Investigators who have implemented STD education programs in U.S. military populations have reported encouraging observations.11,12 Boyer et al. showed that a well-received STD/HIV prevention program could be implemented in deployed military personnel. Their program was successful in increasing STD knowledge and reducing sexual risk behavior.11 Jenkins et al. demonstrated that single-session preventive interventions had some impact in changing STD-related risk behavior, including adherence with recommendations to abstain from sex and increased readiness to change “risky” partner-selection behavior.12
In this study, we assessed the feasibility of implementing a knowledge-based educational intervention for STDs, using the health belief model framework, in male Army recruits starting basic training. This was linked to a screening program for C. trachomatis and N. gonorrhoeae infections. We evaluated the short-term impact of the educational program using questionnaire data.
Materials and Methods
Male recruits entering basic training between July 1999 and June 2000 at Fort Jackson, South Carolina, were invited to participate in the educational program and to provide a urine specimen for screening for C. trachomatis and N. gonorrhoeae. The existing administrative infrastructure of the military training center was used to access volunteers in the physical examination section of the recruit reception area. On Sunday of the first week of in-processing into the Army, a civilian project nurse taught a 1-hour program describing the prevention, symptoms, sequelae, screening, and treatment associated with STDs. This educational intervention was based on the health belief model. Prevention messages addressed condom use and the effects STDs could have on one’s partner, including PID, ectopic pregnancy, and infertility. Special emphasis was given to risk behaviors and providing technical skills such as condom use training to foster behavioral change. Informed consent was obtained, and the guidelines for human subjects research of The Johns Hopkins University and Department of Defense were followed.
Study volunteers were asked to complete questionnaires before and after the educational program. The questionnaire was adapted from questionnaires used in previous published studies measuring STD knowledge, risk perceptions, and behaviors and was reviewed by experts in the field before implementation. Questions asked before the educational program addressed demography, the presence of genitourinary symptoms, and behavioral risk factors. Eight knowledge assessment questions and questions addressing perceived risk of acquiring an STD and intentions with regard to sexual behavior were asked before and after the education program. Questions assessing the volunteer’s perception of the education program were asked at the conclusion of the educational presentation.
For 6 of the 8 questions assessing STD knowledge, the correct answer was “agree”; for the remaining 2 questions, the correct answer was “disagree.” A correct answer was coded as 1 and an incorrect answer was coded as 0. Each knowledge question was analyzed individually and all 8 questions were combined to create a knowledge summary score. The knowledge summary score was calculated as the total percent of correct responses (e.g., 8 correct = 100%; 6 correct = 75%). Changes in participants’ STD knowledge were measured using paired t tests.
Urine specimens were collected from volunteers before the educational program. Specimens were shipped (4°C) to the Johns Hopkins International Chlamydia Laboratory, Baltimore, Maryland, where they were tested using ligase chain reaction (LCR) tests (Abbott Laboratories, Abbott Park, IL) for chlamydia and gonorrhea, according to the manufacturer’s instructions. Laboratory test results were communicated to the project nurse at Fort Jackson. The nurse mailed letters to all recruits with negative results and requested males with positive test results to attend the medical clinic. All participants who tested positive for chlamydia or gonorrhea were evaluated for other STDs and treated according to the STD Treatment Guidelines, Centers for Disease Control and Prevention, Atlanta, Georgia.13
Questionnaire data and laboratory test results were entered into an Access database and analyzed using SAS (version 8.02; SAS Institute, Cary, NC). Participants and nonparticipants were compared using the 2-sample t test and the chi-squared test. Univariate analysis was conducted using the 2-sample t test, chi-squared test, and Fisher exact test for tables with small expected frequencies to compare prevalences of infection in demographic and sexual behavior groups. Predictors of chlamydia and gonorrhea infections were identified using multivariate logistic regression analyses. Variables found to be significant (P ≤0.05) in univariate analysis were input into the final model, and final variable selection was based on the likelihood ratio test.
A total of 4602 males, 90.0% of recruits offered the intervention, agreed to participate in the educational program and screening. Of these, 3911 (85.0%) had complete demographic and laboratory data. Not included in the analyses were 691 recruits with missing age, race/ethnicity, Army component category (regular Army, Army Reserve, or Army National Guard), laboratory results, or some combination of these variables. All evaluable urine specimens collected were studied. The absence of a laboratory test result was the result of the failure of the recruit to provide an adequate specimen after volunteering. Based on an evaluation of the available data, no differences were revealed between recruits with complete data (n = 3911) and recruits with incomplete data (n = 691) with regard to age, race, and Army component.
The distribution of demographic and behavior characteristics is shown in Table 1. The median age of the study participants was 19.9 years, with 87.4% being <25 years of age. The majority of the study participants were white (58.0%). Study participants were attending basic training to enter the regular Army component (60.6%), the National Guard (20.5%), or the Army Reserve (18.9%).
Almost all (92.2%) reported a history of vaginal, anal, or oral sex. Many participants reported high-risk behaviors: 27.3% had 2 or more sexual partners in the previous 3 months, and almost half (47.5%) reported no condom use at last intercourse. Consistent condom use (condom use every time during the last 7 sexual intercourse episodes) was reported by only 25.3%. The primary reason for using condoms, reported by 90.0% of the study participants, was to prevent pregnancy; 70.5% reported using condoms to prevent STDs. Only 2.6% of study participants self-reported a history of a STD as a result of chlamydia, gonorrhea, syphilis, or trichomonas.
Among the 3911 study participants, 184 (4.7%) tested positive for C. trachomatis and 15 (0.4%) tested positive for N. gonorrhoeae, of which 6 (40.4%) were coinfected with chlamydia (Table 1). A total of 193 (4.9%) males had at least 1 positive test result. Only 17 (0.5%) study participants reported any symptoms. In this group of 17, only 1 recruit (0.5%) had a chlamydia infection and none had a gonorrhea infection. The highest prevalence for both chlamydia and gonorrhea were seen in men <25 years of age. For chlamydia, the prevalence was 4.1% in the <20-year age group and 6.5% in the 20- to 24-year group (P <0.0001). The prevalence of gonorrhea was 0.4% in both the <20- and 20- to 24-year age groups (P = 0.44). The prevalence of chlamydia was highest among blacks (10.7%, P <0.0001), as was the prevalence of gonorrhea (1.3%, P <0.0001). Recruits entering the regular Army had the highest prevalences of chlamydia and gonorrhea. However, controlling for age and race/ethnicity, no significant difference in prevalences was observed among regular Army, National Guard, and Army Reserve recruits.
All but 1 case each of chlamydia and gonorrhea were detected in those reporting having had vaginal, anal, or oral sex. The prevalence of chlamydia was higher (5.3% vs. 3.6%; P = 0.01) in recruits with a steady partner, but many participants reporting a steady partner also reported multiple sexual contacts. As expected, the prevalence of chlamydia infection increased with increasing number of sexual partners in the preceding 3 months (P <0.0001). A similar trend was seen with gonorrhea (P = 0.04). Chlamydia infection was not associated with condom use at last intercourse (4.8% and 5.0%; P = 0.77) or with consistent condom use (4.2% vs. 5.8%; P = 0.09). Although only 2.6% reported a history of STDs, prevalences were highest in this group (12.8% for chlamydia, P = 0.0001; and 2.9% for gonorrhea, P <0.0001).
Before the educational program, study participants reported having some knowledge about gonorrhea (81.4%), syphilis (74.5%), chlamydia (64.1%), HIV (94.8%), human papillomavirus (60.6%), and herpes simplex virus (83.4%). Answers to the 8 questions used to evaluate STD knowledge before and after the intervention are summarized in Table 2 as knowledge summary scores (percent correct). The mean score at baseline was 82.0 of 100. There was no difference in the summary score at baseline between study participants who tested positive for chlamydia, gonorrhea, or both (80.4) and study participants who tested negative (82.0) (P = 0.22). After the educational intervention, the mean summary score for all participants significantly increased to 85.2 (P <0.0001). The greatest increase was in the percent that agreed with the statement “Gonorrhea and chlamydia can be cured with antibiotics” (70.0% vs. 90.5%; P <0.0001). Slight decreases were seen in the percent of study participants who correctly answered the statements “Even if you use condoms you can still get an STD” and “A person can get gonorrhea only once; after that they can’t get it again” (88.0 vs. 86.2 and 93.7 vs. 92.1, respectively; P <0.05)
Perception of risk increased greatly after the educational program. Study participants were asked, “Do you think you are at risk of getting an STD?” In response to this question before the educational program, only 17.1% of all recruits answered affirmative. After the educational program, 34.9% answered yes (P <0.0001). There was a significant difference in perception of risk by infection status. Before the educational program, 16.6% of study participants who tested negative for chlamydia or gonorrhea said yes compared with 28.3% of study participants who tested positive (P <0.0001). After the educational session, perception of risk increased in both groups, to 34.1% in study participants who tested negative and 51.3% among study participants who tested positive, and remained significantly greater among study participants who tested positive (P <0.0001).
To determine significant predictors of chlamydia infection, the following variables were included in a multivariate logistic regression: age, race/ethnicity, Army component category, history of a sexual encounter, having a steady girlfriend/partner, self-perceived risk of getting a STD, number of sex partners in the past 3 months, self-reported history of STDs, and condom use during last sexual encounter. Significant predictors of chlamydia infection were young age, black, Hispanic, or other race, multiple sex partners in the past 3 months, and a history of a sexual encounter (Table 3). Predictors of gonorrhea infection could not be determined as a result of the small number of recruits with gonorrhea infections (n = 15).
Changes in intentions were encouraging. When asked “How likely is it that for at least the next 6 months, you will use a condom every time you have anal/vaginal sex?” 51.8% said very likely at baseline and 57.0% said very likely after the educational program (P <0.0001). In response to “How sure are you that you know how to properly use a condom every time you have anal/vaginal sex?” 78.9% were very sure at baseline versus 86.8% after the educational program (P <0.0001). Responding to the question, “How sure are you that you would properly use a condom every time you have anal/vaginal sex?” 63.8% were very sure at baseline versus 73.4% after the educational program (P <0.0001).
Indicators used to assess the feasibility of conducting a combined educational and screening program are shown in Table 4. Recruits reported that the educational program was valuable (96.9%) and 94.6% said the program was a learning experience. The most important aspect of the program identified by participants was: reasons for using condoms (5.6%), how to use a condom (0.8%), knowledge about STDs (40.8%), and all of the above (51.2%).
Mass screening revealed prevalences of chlamydia and gonorrhea infections of 4.7% and 0.4%, respectively, in a nonhealth-care-seeking population of 3911 male Army recruits. A total of 193 (4.9%) study participants tested positive for chlamydia, gonorrhea, or both. If mass screening had not been performed and testing had been limited to only the 17 (0.5%) study participants who reported symptoms, only 1 (0.5%) chlamydia infection and no gonorrhea infections would have been detected.
Molecular amplification assays for urine specimens offer highly sensitive and specific techniques for the identification of chlamydia and gonorrhea infections and allow for noninvasive specimen collection.14 We found urine screening to be a practical means of testing large numbers of male recruits for chlamydia and gonorrhea.14 The structured environment of a recruit reception area provided an opportunity to implement and evaluate a linked educational intervention, building on an earlier experience. Gaydos et al. included a STD educational program in their multiyear, urine-based screening program for female soldiers entering military basic training.15 Their 2-part approach was feasible and similar programs were projected to offer substantial savings in healthcare costs for both the military and civilian healthcare systems.16–20
The linked educational and screening program in our study was both feasible and acceptable to the male recruit population. Our volunteer rate was 90.0%, and all participants found to have an STD complied with instructions for follow up and treatment. Participants reported the educational program was valuable and a positive learning experience. They also reported an increased risk perception, and their intent to use condoms and their confidence in condoms increased.
Earlier studies and the study reported here did not specifically evaluate the cost-effectiveness of the educational component in a linked program in military recruits.15,17,20 Further evaluation of our health education module, based on the health belief model and used in a screening-linked intervention, should cover at least 1 to 2 years and address knowledge retention and impact on behavior. Such an evaluation could be done by tracking utilization of in- and outpatient medical facilities for STDs and STD-related illnesses. Mass and selective screening options should be considered in future evaluations of the screening component. In our study population, a screening algorithm based on age <25 years would have tested 87.5% of our recruit volunteers and identified 95.1% of chlamydia infections and 100.0% of gonorrhea infections.
At the start of our study, a large proportion of participants reported practicing high-risk behaviors and their perceptions of risk were low. Many (193, 4.9%) of these men had at least 1 positive test for chlamydia or gonorrhea, but only 1 (<0.1%) reported symptoms. These findings underscore the need for STD education programs and the importance of screening high-risk male recruits in the absence of symptoms. Military basic training centers allow access to large cohorts of adolescent and young adult men and women who are entering military service.
In calendar years 2001 to 2003, the U.S. Army brought an annual total average of 93,352 male recruits to its 5 basic training centers. These centers offer opportunities for quickly and efficiently conducting screening and educational programs with a high probability that infected recruits will be appropriately evaluated for STDs and treated. Our results show that linked screening and educational programs in male Army basic trainees are needed, feasible, acceptable to recruits, and effective in identifying and treating men infected with chlamydia and gonorrhea. Findings from the short-term evaluation of our educational intervention support implementation of similar programs with longer-term evaluation and cost-effectiveness analyses.
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