The retractable syringe debate

There are a large number of syringes developed for use in healthcare settings that cannot be used a second time, the use of which are, from time to time, proposed for distribution by needle exchange to injecting drug users.

There are a number of terms used to describe this type of syringe - all of which are talking about the same thing:

• retractable syringes;
  

• auto-disable syringes;
  

• difficult to reuse syringes;
  

• safety syringes;
  

• safer technology syringes; and
  

• single-use only syringes.
  

And they have, in our view, only a very limited place in reducing HIV and hepatitis transmission amongst injecting drug users. This article explains why, and outlines the arguments for, and against their use.

The term we prefer to use to describe these devices – which are different because they have a mechanism that can prevent reuse and/or make the needle safe after use – is 'difficult to reuse syringe' (DTRU).

Some 'auto-disable' (there have also been suggestions of developing 'self-blunting' needles to discourage re-use: imagine the damage that could cause!), some require user activation to disable the syringe (it is often possible for the user to sabotage the auto-disable function by removing the components that trigger it).

The consensus of the harm reduction field is that these syringes only have a very limited place in the prevention of the spread of HIV, hepatitis C and other blood borne virus amongst injecting drug users.

Why make a difficult to reuse syringe?
Syringes with devices to make the needle safe and/or prevent re-use have been developed for use in health care settings. The impetus for their development was primarily:

• the protection of health care workers from needle-stick injuries; and
  

• prevention of accidental infection of patients through accidental re-use of injecting equipment
  

in the developed world where the costs of accidental infection, through litigation, to healthcare providers can be very expensive.

It is probable that, in such circumstances, auto disable syringes would be used properly - there would be no reason for professionals to try to circumvent the safety of such devices. It is also possible, that use in these environments would reduce the risks of used equipment from these sources leaking onto the illicit market for re-use by drug injectors.

Following lobbying from the syringe manufacturers and unions use of such syringes has become compulsory in some states in the US. The use of single use syringes by doctors, dentists and nurses etc. in hospitals, clinical and general practice could be instrumental reducing the incidence of needle stick injuries in these environments.

However, the supply of syringes to injecting drug users has been identified by some, manufacturers, politicians, community leaders, and even clinicians as a potential market for 'single-use' syringes, and this is a cause for concern.

Arguments used for supplying difficult to reuse syringes to injecting drug users
The attraction of a device that does not permit more than single use to injecting drug users is easy to see, the arguments proposed are that:

• discarded needles and syringes in public places are a cause of great community concern and infection risk (especially to children) and that these devices will pose less risk and reduce those concerns;
  

• the purpose of syringe provision to injecting drug users is to prevent re-use and sharing of syringes and these devices guarantee that this will not occur; and that
  

• with additional investment to address coverage issues, single-use syringes can offer greater safety and reduction in viral transmission.
  

 
However, counter to the natural intuative idea that they would be a good idea, there are overwhelmingly persuasive arguments against supplying these syringes.



Arguments against supplying difficult to reuse and auto disable syringes to injecting drug users

The main arguments are that:

• even in countries with the very best needle and syringe provision (such as the UK) where supply is at a level to prevent an HIV epidemic, the number of needles and syringes supplied is less than one per injector per day, without massive increase in amounts of equipment supplied single use syringes would lead to increased reuse and sharing of the available resusable syringes;
  

• when needles are in short supply (and they often are) pairs or groups of injectors may have a hit, flush or clean and re-use. Syringes that disable when they have been discharged are much more likely to be used to administer partial loads between 2 or more people. This carries a much greater risk of viral transmission;
  

• although a cause of community distress, discarded sharps are not a public health issue (there has been no recorded case of infection from discarded injecting equipment)
many of these devices can be disabled prior to use, a process that often increases risk of bacterial infection and or tissue damage;
  

• where the device cannot be (or is not) disabled, some have a very powerful spring that rapidly pulls the needle back into the barrel - this can cause serious tissue damage and (with some types) splatter the area with droplets of blood/drug mixture;
  

• even in cases where they they cannot be reused or shared, they cannot reduce injecting or the need for injecting equipment; and, crucially,

  

• for the same additional investment much greater public health gains could be had by increasing the quantities the injecting equipment currently supplied, rather than spending money on technologies that are likely to increase public and individual health risk.
  

These arguments are considered powerful enough for strongly worded cautions against the introduction of these technologies to be issued by bodies such as the English National Needle Exchange Forum (NNEF), the UK Harm Reduction Alliance (UKHRA) and Action on Hepatitis C (AHC) have all raised serious concerns about the introduction of 'difficult to reuse syringes' to needle and syringe exchange programmes. Internationally, concerns have been raised in Australia by the Australian Intravenous Drug users League (AVIL) and others, and drug users, practitioners and researchers in the US and Europe.

Key opponents of single use syringes and their arguments
In a technical paper on the supply of such devices to injecting drug users, mathematiciansCaulkins, Kaplan et al (1998) concluded that the increasing supply of either difficult-to-reuse (single use) or standard syringes could reduce the proportion of syringes used infected with potentially infectious diseases.

They also found that the reduction in risk per additional new syringe is always greater if a standard rather than a single use syringe is added, and that replacing the supply of standard syringes with single-use syringes will increase, not decrease, the incidence of infectious diseases as the standard syringes will remain in circulation longer and be shared more often and by more people.

This is because the number of syringes distributed is seldom anywhere near the number of injections administered. In the UK, around 35 million needles and syringes are distributed to injecting drug users every year. Although this is a large number, with over 100,000 injecting drug users this equates to around one syringe per injector per day. With average injection frequency in excess of 3 injections per day coverage is still well below the optimum one syringe per injection, and reuse of syringes is a common occurrence. Replacing standard syringes with single use syringes will result in frequent reuse (and sharing) of all available standard syringes.

Des Jarlais (2000) has suggested that all syringes that lock automatically after single use can be defeated if sufficient thought and energy are put to the task, and unless there was a truly massive distribution of such single use syringes, their introduction would probably increase sharing amongst injecting drug users.

Dr Alex Wodak was a member of committee set up in Australia that has considered this matter in relation to needle and syringe supply to injecting drug users. The committee looked at the feasibility and desirability of the introduction of single use syringes. It began its deliberations by looking at feasibility on the grounds that nothing was desirable if it was not feasible in the sense of being cost-effective, effective, reliable and safe.

Dr Wodak's opinion at the time was that no one had yet come up with a device design that meets the feasibility criteria. He concluded that at present the technical problems cannot be overcome, and that 'we are therefore forced to the conclusion that if these syringes were introduced, injecting drug users would find ways to reuse them, and that such behaviour could increase rather than decrease risk.'

There is a real risk that the widespread introduction of the supply of single-use syringes to injecting drug users could increase the sharing of scarce "standard" syringes as the reservoir of these decreases.

This could have catastrophic public health implications, especially in places where coverage is poor.

Conclusion
Before general guidance is issued by Health Departments advocating widespread use of auto disable, difficult to reuse single use syringes to injecting drug users the views of injecting drug users, professionals and researchers in the field need to be taken into consideration.
It is essential that pressure on manufacturers and healthcare providers to phase out standard equipment does not lead an increase in, rather than reduction of, harm to injecting drug users, and ultimately, to public health.
There may be a limited place for the introduction of these syringes for supply to injecting drug users, in particular to clients who:

• have a good relationship with the needle exchange;
  

• are collecting enough equipment to give them one syringe per injection;
  

• know they are infected with hepatitis C or HIV; and
  

• are in situations in which other injectors might use their equipment or non-injectors might be at risk of needle stick injury.
  

Joint UK Harm reduction Alliance, Action on Hepatitis C and National Needle Exchange Forum statement on difficult to reuse syringes: July 2001
Single use syringe warning
The English National Needle Exchange Forum (NNEF), the UK Harm Reduction Alliance (UKHRA) and Action on Hepatitis C (AHC) have raised concerns about the introduction of 'difficult to reuse syringes' (DTRS) to needle and syringe exchange programmes.

There are many types of DTRS, each with a different mechanism to prevent a syringe being used more than once. They were developed for hospitals and other health care settings where they can prevent the inadvertent re-use of syringes.

Although it might seem that supplying these syringes to illicit drug users would reduce needle and syringe sharing, it is widely believed that their introduction would lead to those syringes already in circulation being kept, re-used and shared more frequently - leading to an increase in hepatitis C and HIV transmission.

Lambeth and Lewisham Health Authority switched to the new syringes in May, but their introduction at Mainliners was a disaster. In a report presented to the NNEF meeting on Friday 8th June, Gary Sutton said that within days of their introduction a number of problems were identified by users of the service including poor quality needles, 'bendy plungers' and difficulties drawing up. The result was clients refusing to take the new syringes, preferring to go without until supplies of 'traditional' insulin syringes were arranged.

Delegates at the NNEF meeting, UKHRA and AHC have all advised needle exchanges not to introduce these syringes and to liaise with their syringe suppliers, in order to prevent them falling victim to health authorities switching their block purchasing contracts without making special provision for needle exchanges.

Case study by Drew Kramer - director, Harm Reduction Care Network of New York.
New York State came close to deregulating the sale and possession of syringes this year. Although Governor Pataki withdrew at the last minute, the process of advocacy and negotiation around deregulation was instructive, in particular for the role that users played in determining decisions taken. A case in point is the decision on so-called "safer technology syringes".

It is illegal to possess or distribute syringes without a prescription in New York. For years, a bill to change these laws stalled in the New York State legislature. Although there was support for the bill in the State Assembly, the Senate-controlled by conservative, upstate Republicans-could not be moved on the issue. Last year saw a breakthrough. The word spread that the State Senate might be interested in passing a deregulation bill if it was limited to "safer technology syringes."

From its first mention, the Coalition for AIDS Prevention (CAP), a grassroots, state-wide coalition of activists and service providers advocating for de-regulation, was concerned at the implications of the safer technology approach. The implication was that a safety syringe is a single-use syringe. But any sterile syringe which is conducive to safe injection practices is definitionally "safe", including the common syringe now in use. A single-use syringe that would inhibit safer injection practices would not be safe. A single-use syringe that would be unusable for injectors would also not be safe, as such a syringe would have no impact on the scarcity which drives syringe sharing.

But the single-use, lockable syringe, which has a metal collar located inside the top of the syringe barrel, was exactly the product being pushed as the safer technology. The manufacturer claimed that the syringe was bootable. The plunger could be moved up and down freely during injection. To disable the syringe, the user could pull the plunger all the way back, thus engaging the metal collar. At this point, the plunger could only be moved downwards. When it reached the bottom of the barrel, it would lock in place.

Samples of the syringes were obtained and injectors put them to the test. Lockable syringes were hated by all those who tested them. Beyond the fact that the syringe was awkward to use, there were other problems: it wasn't clear how far back you could move the plunger, so it was easy to accidentally lock the syringe. Also, the plunger couldn't be removed. Several users who tried the syringe lost their shot. Following these tests, CAP put forth a position opposing the restriction of deregulation to single-use syringes, stating that anything less than across-the-board deregulation would not serve the cause of HIV prevention. This position was adopted by the State Senate in the bill which Governor Pataki eventually refused to sign.
In the process of rejecting the lockable, single-use syringe members of CAP who were active users also established guidelines for the development of safer injection technologies. These guidelines ensure that safer technologies can be developed which do not interfere with the needs of injectors.

Characteristics of a safety syringe:

• Allows free and full aspiration (up and down motion of the plunger);
  

• Syringe barrel is clearly visible at the point to determine the presence of air bubbles and blood during injection;
  

• Plunger must move freely to permit one-handed injection;
  

• Syringe barrel must be slim enough to allow for the greatest possible positioning of syringe at an angle necessary for injection; and
  

• Removable plunger to allow for retrieval of contents in the event of a syringe failure.
  

• Beyond these essential elements, it is further possible that a safety syringe may:
  

• Allow for reversible, manual, voluntary activation of a disabling mechanism to reduce possibility of third-party syringe reuse or accidental needle stick. Note that this disabling mechanism must be active to the point where any accidental disabling is impossible. This disabling mechanism can involve covering of the needle tip or locking plunger or otherwise disabling the syringe.
  

Characteristics of an unsafe syringe
A syringe which locks or is passively disabled after a single use or can be accidentally disabled; and

A "non-reusable" syringe which is rendered non-reusable in any way that:

• does not permit full aspiration
  

• obscures visibility of contents of the syringe barrel
  

• makes the plunger move with difficulty
  

• means that the syringe barrel is thick to the point at which angle of injection is inhibited
  

• would result in the loss of syringe contents in the event of a syringe failure.
  

Drew Kramer is Director of the Harm Reduction Care Network of New York.

References
Caulkins JP, Kaplan EH, et al (198) Can Difficult-to-Reuse the Spread of HIV among injecting drug users? Interfaces 28; 3; 2-33

Des Jarlais (2000) personal communication with Kay Roberts

Fitwise Advertising and Marketing (2001) Conference calls on the HS to prevent deadly viruses from needlestick injuries. Scottish Nurse 5; 11 May 2001, 8. ISSN 1361-4177

Wodak A (2000) personal communication with Kay Roberts.