Prevalence of Chlamydia trachomatis and Neisseria gonorrhoeae Among Asymptomatic Women Attending the Capital Health Region Clinics in Kuwait

Abstract

Background: 

Data on the prevalence of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections are not available in Kuwait. This study was conducted to determine the prevalence of CT and NG in asymptomatic women attending 4 primary health care clinics in the Capital Health region.

Methods: 

A total of 9239 married women who attended the primary health care centers were offered screening tests for CT and NG over a period of 5 years. Of these, 8539 (92.4%) accepted participation. Low-vaginal secretions were collected and investigated using a molecular strand displacement amplification method. Biodata of all participating women were carefully recorded including age, parity, and nationality. Unmarried women were excluded since nonmarital sex in Kuwait is illegal.

Results: 

Of the 8539 women screened, 69.5% were Kuwaitis while 30.5% were non-Kuwaitis. About 51.3% were aged ≤40 years. The overall prevalence of CT and NG was 2.1% and 1.5%, respectively. The prevalence rates of CT and NG in Kuwaitis versus non-Kuwaitis were 1.9% and 2.3% and 1.4% and 1.6%, respectively. Both CT and NG were detected more in younger than older women; 1.6% versus 0.5% (≤40 years) and 1.2% versus 0.3% (>40 years), respectively. Higher prevalence of both infections was recorded in women in monogamous than polygamous marriages and in illiterate than educated women.

Conclusions: 

The prevalence of CT and NG among asymptomatic women in Kuwait is low compared with rates from other Gulf Cooperation Council countries. Consequently, screening of asymptomatic women is not cost effective and is questionable.

In Brief

This is the first study in Kuwait that highlights the prevalence of Chlamydia trachomatis and Neisseria gonorrhoeae in asymptomatic women attending the primary health care clinics.

Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections are the most commonly reported sexually transmitted bacterial infections in most of the Western countries. In some of these countries, NG infection is less common.¹ Genital infections with CT and NG have the potential of long-term consequences such as pelvic inflammatory disease (PID), chronic pelvic pain, tubal factor infertility, and ectopic pregnancy.^2,3 In addition, CT and NG induce anogenital inflammation and can facilitate HIV infection.⁴ Early detection of these infections is challenging because most women with CT and NG are asymptomatic, but still can transmit the infection and are at risk for complications. Consequently, many medical organizations recommend screening of women who are asymptomatic. Because these infections are easy to diagnose and curable with a single oral dose of antibiotics, early detection and treatment are important component of efforts to reduce the disease burden. Reported cases represent a partial index of disease burden for CT and NG because in 70% to 75% and 80% of CT and NG, respectively, infected women are asymptomatic, and are not detected.^2,5,6 Hence, active screening and treatment programs are critical for prevention of complications. Screening by health-care providers is necessary to reduce the burden of CT and NG infections. In Kuwait, anecdotal reports suggest a fairly high incidence of infertility as well as PID among women seen at the infertility and gynecological clinics; however, there is no available population-based data on the prevalence of CT and NG infections. Also, as there is no systematic screening program, there is insufficient evidence for or against routine screening. Therefore, in the absence of a sexually transmitted disease (STD) clinic or other dedicated clinics as well as data from symptomatic women in gynecology clinics, this study was conducted to determine the prevalence of CT and NG in asymptomatic married women in Kuwait to provide a baseline data for their control and prevention.

METHODS

Study Population

As part of the study protocol, women visiting their primary health care (PHC) center, in the Capital region, between January 2004 and December 2008, were offered screening for CT and NG in addition to standard intake medical procedures. These clinics provide PHC for both the poor and the rich. Kuwait, a very rich oil-producing country, is divided into 4 governorate regions, each with its own Capital Health regional clinics that provide PHC for those living in the country. Women were carefully and explicitly informed of the voluntary nature of the study and informed consents were obtained from participating women. This study was approved by the Ethics Committee of the Ministry of Health, Kuwait. Biodata including, demographic information such as age and nationality (Kuwaiti or non-Kuwaiti) were collected. Kuwait being a traditional Islamic country where nonmarital or extramarital sex is strictly prohibited, married women were only included in this study. Women attending these clinics specifically for the purpose of treatment for vaginal discharge were excluded as management of any positive cases would create legal and social problems, and prevalence of CT and NG is higher in this group of women at any rate.^7,8 The infected participants as well as their husbands were offered appropriate treatment by their attending physician.

Study Design

Self-collected low vaginal swabs were obtained from individual participants. Before collection, participants were instructed to insert a Dacron swab (Becton Dickinson) about 3 cm into the vagina, rotating it 3 times and then withdraw. They were asked to place the swabs immediately inside the provided screw-capped plastic specimen collection tube. The tube along with others was sent to a designated microbiology laboratory at the Maternity hospital for processing. The specimens were then analyzed by the BD ProbeTec ET CT/NG Amplification DNA assay system (Becton Dickinson, Sparks, MD) according to manufacturer's operational manual. This system is an amplified DNA-assay based on simultaneous amplification and detection of target DNA and has been approved by the Food and Drug Administration as a nucleic acid amplification test system with comparable sensitivity and specificity with other NAATs assays.⁹ Sample collection, storage, transport, and processing were conducted in accordance with manufacturer's instructions.

Statistical Analysis

Data entry and analysis were performed using the statistical computer program SPSS version 10. An association between categorical variables was tested by Chi-square and Fisher exact test as appropriate. Cross-tabs analysis was done and P < 0.05 was considered significant.

RESULTS

A total of 9239 asymptomatic women were offered screening test and 8539 agreed to participate, with an acceptance rate of 92.4%. Of these, 176 (2.1%) and 124 (1.5%) were positive for CT and NG, respectively. The highest acceptance rates were among women younger than 20 years and those whose age could not be determined. As shown in Table 1, the women were stratified into 8 age groups with acceptance rate per group and prevalence of CT and NG infections. The highest prevalence of CT and NG was in the age of <30 years accounting for 48.8% of CT and 53.2% of NG infections, which was statistically significant when compared with other age groups (P < 0.0001). Table 2 shows that Kuwaiti women participated more than non-Kuwaitis, 69.5% versus 30.5%, with infection rates of CT (1.9% vs. 2.3%) and NG (1.4% vs. 1.6%). Prevalence of both infections was lower among those in polygamous marriage (CT, 1.5% and NG, 0.5%) as compared with those in monogamous marriage (CT, 2.2% and NG, 1.7%), a difference that was not statistically significant (P > 0.05). Illiterate women were more likely to be infected by both CT (2.7%) and NG (1.6%) than educated counterparts (CT, 1.5% and NG, 1.3%). Dual infection with both CT and NG was recorded in 13, 7.4% of those with CT and 10.3% of those with GC. The trend of CT and NG infections was stable over time, except for a relatively higher prevalence in 2006 and significantly lower rate of NG infection in 2005 (Table 3).

TABLE 1: Screening Acceptance and Positivity Rates of Women Harboring Chlamydia trachomatis and Neisseria gonorrhoeaeat Different Age Groups

TABLE 2: Demographic Characteristics of Participants

TABLE 3: Trend in the Prevalence of C. trachomatis and N. gonorrhoeaeOver 5-Year Period

DISCUSSION

This study, the first large-scale study of opportunistic screening for CT and NG in asymptomatic married women in Kuwait, provided robust estimates of the prevalence of these infections in our country. Primary healthcare setting is a key site for screening infectious diseases in the population. Although the prevalence of infection may be the lowest among healthcare settings, service utilization is by far the highest.¹⁰ We tested over 8500 women by using highly sensitive and specific NAAT testing methodology in a large population attending PHC centers (non-STD) as part of a project designed to measure the prevalence of CT and NG in women in Kuwait. We found that a broad-based screening program was acceptable to women and medical staff in our country. Opportunistic screening, although selective for genital chlamydial infection, the commonest preventable cause of infertility, has also been assessed in Sweden and United States, with success in planned reduction of the CT prevalence.^11,12 Supporting evidence in favor of screening has also come from 2 randomized controlled trials, which concluded that active screening for CT can reduce the incidence of PID in women by approximately 50%.^13–15 A major strength of these prevalence studies of gonorrheal and chlamydial infections in measuring the actual burden of disease is the ability to detect infection, whether symptomatic or asymptomatic. However, measuring asymptomatic burden is important because asymptomatic infections are less likely to be treated and are more likely to contribute to long-term squeal among women. In support of this assertion are some studies which demonstrate that screening for genital chlamydial infection is both beneficial and cost effective in asymptomatic women.^16,17 Many asymptomatic women undergo gynecological procedures such as insertion of intrauterine contraceptive device without screening for NG or CT infections, which may result in dissemination of existing infection to the upper genital tract leading to PID and its complications.

This study provides some salient points worth highlighting. First, the overall prevalence of CT in this study was significantly higher than that of NG (P < 0.001), reaching a peak in 2006. In that year, the prevalence of combined CT and NG was significantly higher than that of the proceeding year for CT and NG (P < 0.0.001 and P < 0.0001, respectively). Second, we found that although detection of CT and NG was higher in the expatriates than in Kuwaitis, the difference was not statistically significant (P = 0.07). Third, it was generally apparent that the overall prevalence rate was low with a steady trend over the study period although there was a slight increase in 2006. Finally, the prevalence of CT in the age group of 20 to 49 years in our study is consistent with previous reviews as well as WHO estimates on the prevalence of CT in low-risk women for the same age group.^5,18,19 Thus, this overall prevalence is also similar to the findings of the studies conducted in primary care settings in Sweden and Greece.^19,20

Limited data exist on the prevalence of CT and NG in the Middle East and Gulf countries, and most of the published data came from point prevalence studies in clinics and hospitals as noted in Table 4. In these studies, the prevalence of CT and NG varied extensively depending on the health care setting, screened population, high- or low-risk groups, and method of testing.¹⁸ Ghazal-Aswad et al.,²¹ in their study of the prevalence of CT in women undergoing screening for cervical abnormality, reported a prevalence of 2.6% for CT in Abu Dhabi, a finding slightly higher than ours. However, in Jordan the prevalence varied depending on the population studied. In a study conducted in a teaching hospital, the prevalence of CT and NG infection was 0.5% and 0.9% and 0.6% and 2.2% among asymptomatic and symptomatic women, respectively,²² whereas in other hospitals the prevalence of CT ranged from 3.9% to 4.6% among infertile women and women attending urology clinic.^23,24 A much higher prevalence rate of 40% in presumed infected women based on clinical examination has been reported by another group in Jordan.²⁵ In Palestine and Iran, rates relatively higher than ours were reported among women in high-risk groups.^26,29 Very high prevalence of antibodies to CT was also demonstrated in a Saudi Arabian study that examined males and females in genitourinary and gynecology clinics.²⁷ In an overview of STDs in Kuwait in 2004 by Al Fouzan and Al Mutairi²⁸ it was stated that the prevalence of nongonococcal urethritis (presumably due to CT) and gonorrhea was 2.6% and 1.6%, respectively, a finding also higher than ours. The highest prevalence rate of CT in the Arabian region has so far come from Egypt with rates of 4.2% in one study³⁰ to as high as 33.3% to 82.6% among high-risk groups in another.³¹

TABLE 4: Comparative Prevalence of C. trachomatis and N. gonorrhoeaein the Middle East

Contrary to a study by Brannstrom et al.¹⁹ that reported nonacceptance of investigation in the younger age group than the older women, our results indicated that the younger women were more willing to be tested as compared with the older ones. An overwhelming majority of participants were Kuwaitis, outnumbering the non-Kuwaitis by a ratio of 2.2:1. The explanation for this disproportionate participation may be because non-nationals were worried about being identified as carriers of STDs and of the possibility of deportation from the country. As our main objective was to study the prevalence of CT and NG in apparently healthy women, we deliberately excluded women with vaginal discharge thus limiting the chance of determining the true prevalence of these infections. However, our overall results suggest that syndromic approach which is discretely practiced is not the rational way to deal with patients infected with CT and NG in this country. Rather, a laboratory-supported evidence-based management would better serve the overall interest of infected women. As was observed earlier by Ghazal-Aswad et al. in United Arab Emirates,²¹ the highest prevalence of CT and NG infections in our study was in the sexually active age group of <30 years, particularly about NG infection (0.8% vs. 0.7% in all other age groups). Dual infection with both bacteria was seen in 3.3% of women aged ≤30 years, whereas a much higher rate of 6.2% was encountered in those >30 years. The number of reported dual infections varies in the literature from <1% to a maximum of >40%.^32,33 Most studies, unlike ours, were conducted in clinical settings among selected patients group and often relate to the proportion of concurrent CT infections in NG infected persons. This may explain the low prevalence in our study as our study population was of the low-risk group mainly because extramarital and sexual relationship with multiple partners are culturally and socially forbidden.

CONCLUSION

This pilot study showed that there is a need for a national screening program that would include all heath regions in Kuwait. Thus, trends in CT and NG prevalence among women can be more reliably monitored. Opportunistic screening for CT and NG in women is feasible and acceptable, and this project demonstrates the ability to undertake such screening program in Kuwait.