The Evolution of How Drug Injection Equipment Harbors Hep C
Hepatitis C, the blood-borne virus that infects an estimated four to five million Americans, is known to easily spread in those who inject intravenous drugs. Although there are many documented modes of Hepatitis C transmission, intravenous drug users have the highest likelihood of becoming infected. A new study out of Germany has found that risk even greater than previously anticipated. The evidence showing Hepatitis C’s survival on and in drug injection equipment clearly indicates a great need for enhancing public health intervention efforts.
A review of four different studies elucidates how our understanding of injection drug use contributing to the spread of Hepatitis C has evolved and, more specifically, how drug injection equipment transmits this insidious virus:
- In a 2008 edition of the Journal of Viral Hepatology, Canadian researchers appraised the evidence regarding Hepatitis C incidence associated with the use of drug preparation equipment such as drug mixing containers, filters and water. They did this by cross-referencing databases and reviewing previous trials that investigated this association. At the time, few studies existed that allowed an adequate assessment of the individual contributions of containers, filters and water to Hepatitis C infection. Because of the short follow-up times, inadequate control of contributing factors and lack of exclusion of periods when intravenous drug users were not at risk for Hepatitis C through drug injection, the scope of their appraisal was limited. Clearly, better designed studies were needed.
- In a July 2011 edition of the Journal of Infectious Diseases, researchers at New York University conducted another meta-analysis of the effects that risk-reduction interventions have on Hepatitis C, and what the most effective intervention types were. The analysts included 26 eligible studies of behavioral interventions, substance-use treatment, syringe access, syringe disinfection and multi-component interventions into their investigation. They found that intervention involving substance-use treatment and support for safe injection were the most effective at reducing Hepatitis C transmission.
- In an October 2011 edition of the Journal of Infectious Diseases (Advance Access) publication, French researchers conducted a study to document the presence of Hepatitis C genetic material in 620 items of used drug injection paraphernalia. Using sensitive molecular techniques, Hepatitis C genetic material was frequently found on syringe pools (38 percent) and on swabs (82 percent) at high concentrations. This investigation, which was conducted in real drug-injecting settings, highlighted swabs as a potential source for Hepatitis C transmission.
- Most recently, in a January 2013 edition of the Journal of Infectious Diseases, German researchers investigated the risk of Hepatitis C transmission by analyzing the direct association of this virus with filters, water to dilute drugs and water containers. Experiments replicated practices by people who inject drugs with routinely used injection equipment. Hepatitis C stability in water was assessed by introducing the virus to bottled water. Viral association with containers was investigated by filling the containers with water, contaminating the water with Hepatitis C viral particles, emptying the water and refilling the container with fresh water. Transmission risk associated with drug preparation filters was determined after drawing the virus through a filter and incubating the filter to release infectious particles. By far the most in-depth study to date, the researchers found that the Hepatitis C virus can survive for up to three weeks in bottled water – even after rinsing the container. In addition, the virus can survive on the filter material.
Although the concept of Hepatitis C surviving in a washed water bottle is a bit daunting, remember that the virus is only spread through blood-to-blood contact. Thus, the surviving viral particles only pose a hazard to its introduction into the blood supply – as occurs with intravenous drug use. Because dilution of intravenous drugs with water is commonplace, a water bottle used with drug injecting equipment can be a source of Hepatitis C transmission.
Regardless of the vehicle, the evidence linking injection drug use with Hepatitis C transmission continues to grow. The German study finding Hepatitis C’s tenacious stability in a swab, filter or rinsed water bottle adds an even more urgent incentive calling for public health interventions to educate injection drug users on the importance of eliminating all equipment-sharing practices.
References:
http://www.natap.org/2011/HCV/110411_03.htm, Hepatitis C Transmission in Injection Drug Users: Could Swabs Be the Main Culprit?, Vincent Thibault, et al, Retrieved January 20, 2013, Journal of Infectious Diseases, October 2011.
http://www.ncbi.nlm.nih.gov/pubmed/18208496, Risk of hepatitis C virus transmission through drug preparation equipment: a systematic and methodological review, De P, et al, Retrieved January 20, 2013, Journal of Viral Hepatitis, April 2008.
http://www.ncbi.nlm.nih.gov/pubmed/21628661, A systematic review and meta-analysis of interventions to prevent hepatitis C virus infection in people who inject drugs, Hagan H, et al, Retrieved January 20, 2013, Journal of Infectious Diseases, July 2011.
http://www.ncbi.nlm.nih.gov/pubmed/23129759, Transmission of hepatitis C virus among people who inject drugs: viral stability and association with drugpreparation equipment, Doerrbecker J, et al, Retrieved January 20, 2013, Journal of Infectious Diseases, January 2013.