(P330) Self-collection of capillary blood using a new device for HIV and syphilis testing among men who have sex with men that use PrEP in the Netherlands

Background. In recent years home-based opportunities for testing HIV and STIs have become available. Collection of blood is required for reliable (laboratory) results on Syphilis and HIV testing. Current self-sampling with fingerstick collection are often not adequate for sufficient capillary blood collection. The Tasso+ blood collection device has the potential to collect larger blood volumes and therefore is suitable for home-based sampling for HIV, Syphilis testing and possibly creatinine levels (PrEP monitoring). This study assessed acceptability and feasibility of this device among men who have sex with men (MSM) who currently use PrEP and, performance of the device (i.e., blood volume collection).

Methods. Between August 2022 and January 2023, we have recruited 47 MSM during their regular routine PrEP consultation (with STI, HIV and creatinine screening) at two Dutch STI Clinics. Participants tested the Tasso+ device directly after their consultation. An online questionnaire determined acceptability and feasibility of the device and home-based sexual health care in general, including 5-point Likert scale items. Volumes were measured after sampling, after centrifugation (serum volume) and remaining serum volume after performing routine screening tests for HIV and Treponema pallidum.

Results. Based on direct experience 87% of participants (N=47) had positive attitude towards the use of the device, 77% would use it again in the future for blood sampling at home. The device was judged as easy to use (96%) and participants were confident to collect blood at home with this device (94%; self-efficacy). Results showed that the device collected on average 537µl whole blood (244µl serum). Nearly all samples (92%) had sufficient blood for Treponema screening and HIV screening. After screening, an average of 189µl was left, estimated 85% of samples could potentially be tested for creatinine levels.

Conclusion. Self-collection of blood with this device is highly acceptable among PrEP-using MSM. Potential for future use for home-based testing is high. Use of the device has been largely feasible for collecting sufficient blood volumes for required Syphilis and HIV tests and possibly additional tests (creatinine). Therefore, home-based testing including blood sampling with the Tasso+ device may be considered a valuable addition among PrEP-using MSM.