Commentary by Ellen Pittman, Lea E. Widdice, MD, University of Cincinnati

Screening, treatment, and education to prevent future infections among populations at risk for sexually transmitted infections (STIs) are critical components of public health efforts to control STIs, including chlamydia. Typically, chlamydia screening is accessible only in traditional health care settings, such as medical provider’s offices, health care clinics, or hospitals. However, to increase access to screening, some health care systems, nongovernmental organizations and community based health outreach programs are offering screening in mobile health care settings. Mobile screening can be offered in a variety of locations, including vans or large recreational vehicles converted to provide medical services; rooms in churches, brothels or bars; and outdoor, community gathering places.

STI screening in mobile settings can increase access to chlamydia screening for populations at risk for STIs and populations faced with barriers to accessing screening in traditional settings. Mobile screening programs for STIs, including HIV, have been established and evaluated in both low-resource and high-resource settings. Results of evaluations suggest pro-grams can be acceptable, feasible, and effective.1-12 Successful programs have demonstrated reaching populations with high prevalence of infection and reaching populations with low prevalence of testing. At least one evaluation has demonstrated increased risk reduction behaviors and decreases prevalence of chlamydia among female sex workers.1 In addition, other components of successful programs include ensuring treatment of detected infections and linking clients with the traditional health care setting.

STI screening in mobile settings can increase access to chlamydia screening for populations at risk for STIs and populations faced with barriers to accessing screening in traditional settings.

A potential barrier for programs offering chlamydia screening in mobile settings is loss of privacy for clients when they are seen by others entering a van or speaking with program staff known to be offering screening. How-ever, this appears to not deter at-risk individuals from seeking screening. In fact, visibility of the mobile site and clearly published schedule announcing upcoming visits are identified as motivators to seek screening.3,6 In the United States, we have offered chlamydia screening to men and women at outdoor, community-organized, family-focused events and on a public square in a metropolitan business district during the lunch hour. At each event, the requests for screening out-numbered our capacity to provide on-site screening.

Another potential barrier for mobile chlamydia screening are costs, including startup, infrastructure, and staff-ing. Few reports of mobile STI screening programs provide programmatic cost data despite cost considerations being critical for program initiation and sustainability.13 If mobile screening programs reach populations already accessing health care in traditional settings and not uncovering hidden disease, they will only be cost-effective if they can deliver care at a lower cost per case treated than screening in a clinical screening.14

Rapid, easy to use, point of care (POC) testing for chlamydia may in-crease the feasibility and impact of screening programs. At this time, no POC, CLIA-waived diagnostic test for chlamydia is available in the United States. Most chlamydia screening pro-grams obtain specimens that are transported to an off-site laboratory for testing. Therefore, mobile screening programs must have staff, expertise, and materials dedicated to packaging and transporting samples, receiving results days after sampling, and contacting clients who have positive test results. Additionally, diagnostic tests for chlamydia are not routinely validated for sample collection outside of a fixed health care clinic. We have assessed the feasibility of POC testing as part of a mobile screening program on a health van using a diagnostic test for trichomonas that is FDA-cleared, CLIA-waived and provides results from a self-collected vaginal sample in 10 minutes.12 During two community events, we provided STI screening from a mobile health van. Uptake of the POC trichomonas test was 100% (31 women tested) and 100% of those infected (four women) were success-fully contacted with their results and treated. Acceptability among men and women of point-of-care testing in mobile settings was measured using a written survey. The proportion of men and women who reported getting POC testing on a health van as acceptable was higher if the wait time was shorter; of the 30 respondents, 76% reported that a wait time of less than an hour was very acceptable, 58% reported that wait times of one to two hours was very acceptable, 48% reported that wait times of two hours but less than a day was acceptable.

We have also demonstrated the use of a POC chlamydia diagnostic test during a mobile screening event.12 Attendees at a community event request-ing chlamydia screening on a mobile health van were offered participation in a research study; participants were given a choice between getting results from a non-validated POC chlamydia test on the same day or a validated, laboratory-based chlamydia test in two-weeks. Each research POC test was confirmed, with 100% agreement, with a laboratory-based confirmation test. A majority (22/25, 88%) of men and women chose to get results from the non-validated, POC test. Of the 22 participants tested, two had positive results and both received treatment.

Screening for chlamydia requires sample collection of urine or genitals, limiting mobile screening programs to locations with access to bathrooms or private rooms for sample collection.2 During our efforts to provide screen-ing at community events with a mobile health van, our capacity to offer testing was limited by having only one bathroom on the van for sample collection and limited space for counseling, education, testing, and reporting results. Therefore, we explored the feasibility and acceptability of offering screening without a van by using vendor’s booths—for education, counseling, and result notification—and privacy shelters for patients to self-collect genital samples. Privacy shelters are pop-up tents designed for standing or sitting. At two outdoor community gatherings, we offered chlamydia and gonorrhea screening without a van. Privacy shelters were set up next to the vendor booth. We used commercially available tents as privacy shelters. Staff offered clients either a privacy shelter or nearby public bathrooms to self-collect vaginal or penile samples. When given the choice, all men and women used the privacy shelter. We assessed attitudes about sample collection in privacy shelters compared to other locations. More men and women reported that self-sampling in a privacy shelter (62% and 67%, respectively) was acceptable compared to a mobile public toilet, e.g. a Porta Potty (32% and 12%, respectively). Fewer men and women reported self-sampling was acceptable in a privacy shelter as a doctor’s office or home (89% and 95%, respectively) (unpublished data). Using privacy shelters has the possibility of expanding access of STI screening into environments without access to bath-rooms or built-in private settings.

STI screenings in non-traditional settings offers a more accessible route to care for at-risk patients and communities with difficulty accessing medical care. Effective programs utilizing screening in mobile settings can be developed by working with community-based partners to identify barriers and solutions to offering STI screening. Programs offering STI screening have demonstrated that individuals at risk for STIs will get tested at community events. POC testing in mobile settings is acceptable and self-sample collection on vans and in privacy shelters is acceptable. A current barrier preventing wider adoption of screen-ing in community settings is the lack of a CLIA-waived POC test for chlamydia and poor understanding of the costs for initiating and sustaining mo-bile screening programs.

References

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