Overview of included studies
In total 121 pieces of evidence were identified, these included 106 from the systematic searches plus a further 15 from citation searching and the targeted search for HR messaging. After de-duplication, 86 pieces of evidence were entered into the second round of screening.
Twenty-six pieces of evidence were excluded after abstract screening (see Table 2), leaving 60 pieces of evidence identified as appropriate for inclusion in the review. The majority (n = 20) of these exclusions were due to no information about HR interventions. Appendix 2 outlines the key details of the included studies (see Additional File 2).
Of the 60 pieces of evidence identified, 48% (n = 29) were expert opinion pieces (of which most were academic experts).
There were also 11 studies (mainly case reports, descriptive or qualitative). In instances where multiple reports were available from the same study, this was included as one piece of evidence.
There were four non-peer reviewed evidence reviews included.
The review covered 16 pieces of grey literature classified as guidance, which included COVID-19 related HR messaging for PWID. This type of messaging was not always directly available on Government websites but they often sign-posted to messaging produced by reputable non-Governmental organisations (NGOs), think-tanks or service providers so these have been included.
Based on the types of evidence included in the review, the quality would be considered low-moderate.
Table 3 shows the range of countries that the pieces of evidence were from.
Included evidence by country
Evidence (n = 60)
Canada and US
International (i.e. more than one continent)
Designating HR services as essential
Designating HR services as essential, so that they are not suspended in the event of a pandemic type scenario, has been recommended by many experts(7,8) and globally recognized bodies, including the International Society of Addiction Medicine (ISAM)(9), the International Network of People who Use Drugs (INPUD)(10) and the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA)(2). There is no clear consensus, however, on which HR interventions to prioritise when staff or resources are limited.
Continued unrestricted access to HR services, such as NSP(9), could be facilitated by ensuring an adequate supply of personal protective equipment (PPE) for staff(7,11,12).
By designating HR as essential, these services can not only sustain their vital work but also offer additional functions(13). For instance, as PWID are likely to be more vulnerable to any pandemic disease, and the impacts of their substance misuse may mask or mimic disease symptoms, frequent screening for the pandemic infection within HR services is recommended(9,14). Additionally, supplies of sanitizing materials can be included within HR packs(14,15).
An initiative to provide ‘essential journey’ cards, that PWID may use when collecting medications during lockdown, is yet to be evaluated but has been recommended by some authors(16,17).
Continued access to blood borne virus (BBV) testing and treatment for PWID is vital to identify cases and reduce transmission(13); innovative ways to deliver this, such as rapid testing, need to be identified(14).
Developing emergency plans
Emergency preparedness of HR services needs improving22. This may include developing contingency plans, such as for periods of equipment or medication shortage, which detail how HR services will be maintained (e.g. outreach, home delivery, virtual/phone consultations)(2,11,15). The Larney & Bruneau (2020) review of the impact of ‘big events’ on substance misuse services emphasised the importance of emergency planning and reported that they found no publications describing how HR and drug treatment service providers should prepare for an emergency(19).
Adjusting HR services to comply with social distancing
Numerous papers have recommended ways in which HR services can remain open and comply with social distancing(20) such as through adjusting patient flow(11) or mechanical segregation(21); the methods suggested for specific HR interventions are detailed below.
In terms of NSP, various alternatives to conventional collection are possible. For instance, a UK study concluded that home delivery, provision by post, peer supported distribution, and vending machines should be considered. All these methods, apart from vending machines, are currently being implemented to various degrees across the UK, and it is important that they are extended to ensure equitable access to all PWID.(22)
The authors of the UK study acknowledge that vending machines may be challenging to get in place quickly because of their sourcing and installation. They also point out that there are already direct postal sales of injecting equipment to some people who inject image and performance enhancing drugs so establishing free postal needle/syringe provision to all PWID could be relatively easily achieved by utilizing existing delivery services.(22) However, evidence of how such services should be coordinated, and associated governance considerations, has not yet been established.
Other authors also recommend vending machines, which provide 24-hour access, and no-contact collection(7,8). The LUCID-B study in Bristol reported positive feedback from PWID in relation to home delivery because it meant they did not have to travel, it kept them safe from COVID-19 and it prevented re-use of equipment(23).
The Larney & Bruneau (2020) review of evidence from other ‘big events’ concluded that, in a pandemic type scenario, NSP should offer as many needles and syringes to clients as requested and that flexible NSP, such as mobile or outreach models, will increase access(19). Other authors have also recommended this ‘low threshold’ approach (as opposed to one-for-one exchange) to needle/syringe provision(7,24).
Similar to NSP, outreach and home delivery have been recommended for OST in a pandemic type situation(15,25). Flexibility for services to relax supervision and increase take home doses has also been suggested(8,12,13,15,21). Many authors state that these changes should be based on the stability of the patient, with highest risk patients still able to access the clinic(9,16,26–28). Clearly there are inherent risks in this approach but methods, such as the use of technology (e.g. “smart” pill bottles/lock boxes that dispense doses on a remotely set timescale), would mitigate them(29).
This review found examples of new models of delivery of OST services. For instance, in Rhode Island USA, regulatory changes meant that initiation of OST by telephone could be developed; whilst the authors are positive about this approach, it has not yet been evaluated(30).
In Ireland a model of remote care has been developed which begins with an assessment of COVID-19 risk by telephone followed by a single-patient visit to local services to provide a point of care drug screen and complete necessary documentation. Contact episodes are maintained through remote video assessment and ongoing management by a primary care addiction specialist. This model is yet to be evaluated but it appears to offer lower COVID-19 transmission risks, increased access to OST and reduced waiting times.(31)
Much of the evidence makes recommendations around telehealth(14,25,32,33) as well as describing other technology that HR services could utilize, including smartphone and web-based interventions, text messaging for continuing contact and care, machine learning, and wearable devices, including digital phenotyping and ecological momentary assessment, biofeedback, and virtual reality(34,35). Lead time and availability of technology (for both services and clients) will limit implementation of these options in the short term with text-messaging, smartphone and web-based interventions being the most simple and quick to roll-out.
One USA telehealth provider, Bicycle Health, has reported how it adapted its services to respond to COVID-19 guidance, such as urine testing via video link(36). However, others have highlighted potential problems with these virtual solutions, such as the patient not having access to a private space for the call(29), and the risk of exacerbating inequalities which is considered further below.
Several authors suggested buprenorphine as a safer take home option than methadone(29,31,37) and providing it as depot (long-acting injection) was recommended(8,38).
There is conflict between social distancing and the physically, socially, and emotionally intimate nature of injecting drug use(39); for instance, naloxone, as a HR intervention, relies on social connections. Several authors have suggested, that during a pandemic type situation, naloxone should be made more accessible (with appropriate patient and family education) because of the increased overdose risk resulting from using drugs alone when socially distancing and due to uncertain supply(29,35).
One author suggests virtual injection supervision, which allows individuals to inject in the presence of an observer on the internet who is prepared to intervene in the event of an overdose or virtual peer support which also uses the internet to make social support available to PWID at a physical distance.(39) Alternatively a US study of NSP changes during COVID-19 recommended scheduling a phone check-in after use for people who are using alone(14).
Several authors have suggested ‘safe supply’ (defined as a legal and regulated supply of drugs that traditionally have been accessible only through the illicit drug market) could provide a solution to the conflict between social distancing and HR(40,41). One piece of evidence describes an unpublished study which found those receiving prescription alternatives to illicit drugs are able to avoid more routine contacts with drug dealers and can reduce activities that might put them at risk of acquiring or transmitting pandemic infections (e.g. sex work), however, the authors acknowledge that a full evaluation is needed(42).
Role of Pharmacies
Many authors highlighted the important role of pharmacies in delivering HR interventions during a pandemic type situation if other services become unavailable(2,43–45). However, at such times, pharmacies may have reduced opening hours(31). PWID who participated in the LUCID-B study reported finding the long queues for pharmacies at the start of lockdown very off-putting(23).
Much of the evidence suggested that HR needs to be part of a holistic approach to supporting PWID during a pandemic-type situation. For instance, several authors have emphasized the need for enhanced mental health support for PWID during a pandemic-type situation, with video or internet-based psychotherapy and phone counseling generally recommended(9,11,18,19,38).
Messages about how to access healthcare have been recommended as PWID may no longer have opportunistic access to treatment service staff and, therefore, may miss discussing wider physical health issues(23).
Links to social and economic services were also emphasized as important. For instance, ‘Housing First’ was highlighted as an approach which can facilitate social distancing and provide stability for PWID to engage in HR and manage extended OST take home doses appropriately(33,34). With increased duration of take home OST, one review concluded that accommodation for the homeless should have capacity for the safe storage of medications and space to designate as a safer use room(38).
A pandemic type scenario has the potential to exacerbate health inequalities already experienced by PWID, such as increased morbidity and mortality and reduced service provision(33). Additionally, much of the evidence indicates a risk of widening inequalities within the injecting drug population by moving to interventions that require PWID to have access to a particular level of technology to be able to engage(29,32,34,35,39). Providing mobile phones to clients(23,29) or using peers to engage with the most marginalized PWID in their community(22,24) are suggested strategies to mitigate this risk.
Overall, in the available evidence, there was little consideration of sub-groups within the population who inject drugs; one Ukrainian study considered older people as a sub-group of PWID finding that they need social support to engage in care(46) whilst another piece of evidence suggested needles/syringes should be provided by home delivery for PWID living in non-urban areas(7).
The Larney & Bruneau (2020) review found few studies considered the impact of ‘big events’ specifically on women meaning there is limited evidence to inform women-specific and gender-sensitive COVID-19 responses for women who use drugs. They suggest this is important because women who use drugs are vulnerable to gender-based violence, and scarcity of drugs is likely to exacerbate conflict and risks of exploitation and/or victimization.(19)
Developing a communications plan, at individual service level, is suggested in the literature(15). Other authors stress that HR information materials should be made inclusive by ensuring they are suitable for various cultures, available in different languages/formats(16) and distributed through multiple new channels of communication, such as mobile apps, peer networks and social media sites(16,23,26).
Due to the lack of evidence on HR messaging, a search was done of the communications provided during the COVID-19 pandemic by key national bodies and service providers. With the exception of the USA(47), Government websites did not tend to provide direct messaging for PWID but they did sign-post to other independent resources which have been included in this review.
Important HR messages identified in this review can be grouped under the themes of infection control, and uncertain drug supply as detailed below: -
Messaging relating to Infection Control:
Most of the messaging considered in this review included COVID-19 related hygiene advice, such as hand washing and cleaning surfaces(47–54). This was also highlighted by a group of Canadian experts(15) and many other authors stated the importance of using HR services to educate about infection control measures(2,8,14,24,33,38)
Cleaning the packages that drugs are supplied in (e.g. with alcohol wipes) was covered in some messaging(49,51,52) and expert opinion(15). Not carrying drugs packages in the body (e.g. mouth, rectum, vagina) was also mentioned(49,52,54).
Advice for PWID to prepare drugs themselves and avoid sharing equipment was common to almost all the messaging included in this review and was backed up with guidance around stocking up on supplies of equipment (such as needles and syringes)(47–57). Most authors suggested at least two weeks(48,51,52,54) supply of equipment but some recommended 3-4 weeks’ worth(49,53). Some messaging went on to include advice on how to clean syringes in the event of running out of supplies(4,47,51,53).
A Canadian expert group also suggest that public health messages around self-isolation and social distancing should be modified for people who use drugs, who live in shelters or who are involved in sex work(15). Some of the messaging included in the review did specifically provide advice for sex workers to limit close contact(48,53).
The USA Government guidance explicitly recommends that PWID make use of the other services offered by NSP such as testing for BBV(47).
The WHO suggests HR messaging should be used to dispel myths that substance use somehow protects a person from infection(12).
Messaging relating to uncertain drug supply
An international group of experts recommended that messaging needs to include information about overdose risks associated with changes in the quantity and quality of the drugs market(24) and most of the messaging included in this review did cover this. For instance, advice for PWID included using a test dose, or small amount, initially to see how it makes them feel(47,48,51,56). Some messaging advised stocking up on drugs/having a reserve in case of shortages(49,53,54) with others warning about the legality and dangers of obtaining large amounts of drugs(48,52). One US study also concluded that educating participants on the increased risks of overdose through supply disruptions should include advice to cautiously increase personal supply in the event of a shortage(14).
Most messaging followed on from explaining the supply issue with advice about reducing the risk of overdose by accessing naloxone or by making a plan with family or friends to check in after using drugs(47–51,53,54,56,57).
Guidance on managing involuntary withdrawal, such as stocking up on medications to relieve symptoms, was mentioned in much of the messaging because of the risk of drugs being in short supply or PWID not being able to access them due to self-isolation(48–54).
One of the UK service providers advises PWID to consider snorting rather than injecting during the pandemic as it is less risky when the quality of supply is unknown. They also suggest administering doses slowly when injecting to allow the drug to take effect, in order to reduce the likelihood of accidental overdose.(56)