Recovering Infectious HIV from Novel Syringe-Needle Combinations with Low Dead Space Volumes

This study determines if detachable syringe-needle combinations redesigned to reduce their dead space volume may substantially reduce the burden of exposure to infectious HIV among people who inject drugs. Two novel, low dead space (LDS) syringe-needle designs-one added a piston to the plunger (LDS syringe) and the other added a filler to the needle (LDS needle) to reduce their dead space-were compared to standard detachable needle-syringe combinations and to syringes with fixed needles. LDS and standard syringes attached to LDS and standard needles of 23-, 25-, and 27-gauge size were contaminated with HIV-infected blood in the laboratory. The proportion of syringe-needle combinations containing infectious HIV was analyzed after syringes were (1) stored up to 7 days at 22°C or (2) rinsed with water. Detachable syringes attached to 25-gauge needles yielded comparable proportions of syringes with infectious HIV, whether the needle was standard or LDS. Among needles of greater diameter (23 gauge), LDS needles tended to reduce recoverable HIV to a greater extent than standard needles. Syringes with fixed needles showed superior results to LDS syringes attached to needles of equivalent diameter and were less likely to get clogged by blood. Detachable LDS syringe-needle designs must be recommended with caution since they still pose potential risk for HIV transmission. Distribution of LDS syringes and needles must be accompanied by recommendations and instructions for their proper rinsing and disinfection in order to reduce viral burden and chances of needle clogging.