subject: Developments in STD Screening - Alternative Methods of Chlamydia Testing [print this page] Developments in STD Screening - Alternative Methods of Chlamydia Testing
Clinicians who are reluctant or too busy to perform pelvic examinations to collect cervical swabs for chlamydia screening now have the opportunity to screen females with either urine, which can be collected in multiple settings, or vaginal swabs collected by the clinician or the patient in clinical settings. Patients fearful of an invasive procedure now can submit urine or a self-collected vaginal swab for screening. Use of self-collected samples for chlamydia testing may eliminate some screening barriers.
Urine testing has facilitated expansion of chlamydia screening programs and has shown to be widely acceptable to patients, healthcare providers and laboratory staff. However, urine testing is not without disadvantages. Patients may be reluctant to provide a urine specimen due to fear of undisclosed drug testing. Also, urine specimens are unlikely to be feasible for home-based testing, due to restrictive requirements for bulky packaging of moderate volumes of fluid (i.e. 30mL or 1 ounce).
Continued expansion of chlamydia screening likely will rely on more consistent screening in primary care as well as screening in community-based venues, especially in areas with high prevalence. Potentially, urine specimen collection will be feasible using low-cost medical staffing models or trained, non-medical personnel. The next promising alternative is home collection.
There has been much interest recently in the possibility of using samples collected at home for direct mailing to a laboratory for testing, thereby by-passing the clinic all together for routine screening when the individual does not have symptoms. Although home collection is not yet FDA cleared, the focus of current research has shown that vaginal swabs can be collected at home and sent through the U.S. mail to a laboratory for testing13, 16, 21. Several studies have indicated that home collection is preferred by many to most women16, 21.
In order to obtain clearance from FDA for use of innovative sample types so as to facilitate more widely accessible tools for chlamydia screening, more research is needed on alternative sample types such as SOVS collected at home, rectal swabs, and pharyngeal specimens. Additional health services research is needed for improving and implementing the use of urine screening in alternative, community-based settings by non-medical personnel.
The development and improvement of point-of-care tests for chlamydia screening will be required to facilitate immediate treatment of infected individuals before they leave the health care setting. Cost effectiveness models and cost comparisons of different approaches to chlamydia screening will be needed in order to guide the most judicious use of scarce health care resources. Education of both clinicians and individuals at risk for chlamydia infections will be necessary in order to remove barriers that exist now for routine screening of young women. Resources and recommendation are needed for screening men.
Currently, the CDC does not recommend a test-of-cure following chlamydia treatment. However, because incidence studies have demonstrated that previous chlamydia infection increases one's probability of becoming reinfected30, CDC recommends that previously infected individuals be rescreened three months after treatment, a test of reinfection, for chlamydia or gonorrhea.
