Sharing drug preparation paraphernalia may not significantly contribute
to hepatitis C virus (HCV) transmission among people who inject drugs,
according to a study recently
published in The Journal of Infectious
In an experiment designed to mimic real-world injection practices, the
researchers were unable to detect HCV in cookers, and seldom able to do so in
filters, after these items were exposed to the contents of syringes known to be
contaminated with the virus.
Needle exchange and distribution programmes that provide sterile
syringes have been credited with substantially reducing transmission of
blood-borne diseases including HIV, hepatitis B and hepatitis C among people
who inject drugs.
These viruses – especially HCV, which is able to live outside the body
longer than HIV – can potentially be transmitted through any item that comes
into contact with blood. Most harm reduction programmes therefore offer drug
preparation equipment such as cookers (bottle caps or other small receptacles used
to mix drugs), filters (cotton or other material used to strain a drug
solution) and clean water, in addition to syringes.
Robert Heimer of Yale
University School of Public Health and colleagues conducted a study to look for
HCV in drug preparation paraphernalia under conditions similar to those that
occur when people share drugs.
Previous studies by Heimer and
others have suggested that cookers and filters can transmit HCV. However, it is
unclear if HCV infections linked to sharing paraphernalia reflect contamination
of the paraphernalia itself, or if the virus spreads through syringes when
drugs are shared, the authors noted as background.
The researchers designed laboratory
experiments to replicate real-world injection practices among people who share
drugs. Often people will jointly obtain a bag of heroin, for example, which one
individual mixes in his or her syringe, and the solution is then portioned out
to the others. Older and more experienced users – who have had more
opportunities to acquire HCV – may be more likely to do this drug preparation.
The residual contents of ‘input’
syringes known to be contaminated with HCV were passed through cookers and
filters and transferred into a second ‘receptive’ syringe. The study tested
syringes with detachable needles and those with fixed needles (e.g. disposable
insulin syringes). All items were then tested for the presence of infectious
HCV could not be recovered
from cookers, regardless of cooker design or the type of syringe used,
according to the report. The virus was only detected in input syringes with
detachable needles, not those with fixed needles (73.8 vs 0% detection).
HCV was seldom found in
filters, but this happened more often when detachable needles were used
compared with fixed needles (15.4 vs 1.4% detection). Finally, HCV was about
twice as likely to be detected in the receptive syringe if the input syringe
had a detachable instead of a fixed needle (93.8 vs 45.7% detection).
These results are "consistent with the hypothesis that
sharing paraphernalia does not directly result in HCV transmission, but is a
surrogate for transmissions resulting from sharing drugs," the study
authors concluded. They suggested that this kind of sharing "is a
surrogate for situations in which HCV-discordant injectors share drugs,"
meaning one individual is HCV-positive and the other HCV-negative.
The findings, they added, have
implications for HCV prevention efforts and programmes that provide education
and safe injection supplies for people who inject drugs.
team suggested that in light of these results, syringe access programmes should
not spend their limited funds on cookers and filters, but should instead focus
their efforts on distributing more syringes with fixed needles.
minimum, our findings should compel programs that serve [people who inject
drugs] to focus more on the process of drug preparation and injection and less
on the preparation paraphernalia," they wrote. "Going further,
programs may want to reconsider expending scarce resources to provide supplies
that will do little or nothing to prevent HCV transmission."
Some harm reduction advocates, however, take issue with this conclusion. Beyond
HCV transmission, providing clean cookers and filters can also help prevent
bacterial infections and 'cotton
fever'. And these supplies are inexpensive, so omitting them
would not free up much money.
"We are in the midst of a syringe exchange
funding crisis, as a surge in demand (more people who inject drugs) plus a
tremendous growth in new programs has dramatically outpaced availability of
public and private funds," said Daniel Raymond of the Harm Reduction
Coalition. "However, any discussions or decisions about scaling back on
purchasing or provision of cookers, etc, should be driven by people who inject
drugs and program participants, who may place values on these supplies
independent of their utility in HCV prevention."