Findings from novel methods of surveillance for fentanyl and novel psychoactive substances within Supervised Injecting Facilities

Australia is yet to see consistent signals of fentanyl-contaminated heroin, despite widespread emergence in other countries. This study tested novel methods to monitor for fentanyl and novel psychoactive substances (NPS). Clients from two medically supervised injecting facilities (SIFs) contributed urine screens with BTNX Rapid Response™ fentanyl test strips (FTS) paired with surveys, and injecting equipment associated with opioid overdoses for laboratory analysis. A single site piloted drug checking with FTS with laboratory confirmation. Two online workshops were conducted with key experts (n = 21, including SIF staff, content experts and people with lived experience) to understand how results may inform future testing for NPS within the supervised injecting facilities.

Of the 911 FTS conducted on urine, 17 yielded positive results, of which 8 were not explained by self-reported fentanyl use. Confirmatory laboratory analysis was conducted on six, with four deemed to be false positives, and two confirming fentanyl presence. Injecting equipment tested from 59 overdoses did not find fentanyl and other NPS. Drug checking with FTS (n=40) showed four positive results. Two were laboratory tested and classified as false positives. Workshop participants felt routine monitoring for FTS may have limited value currently, until there is a significant change in overdose rates, or other signals to warrant testing. A process for using pre-defined signals to trigger surveillance was defined.

This study demonstrates the feasibility of quick onsite testing for fentanyl. However, the high false positive rate emphasizes the need for confirmation of positive FTS through advanced analytical techniques, and the need to better understand drivers of false positives, such as test interpretation and adulterants. While the role of routine FTS use is unclear within the current low-fentanyl context, a rapid response process was established should signals of increased fentanyl prevalence in the Australian heroin market emerge.