Alcohol swabs and intramuscular injections: where do we stand?
Confusion and concern started to sweep across the UK towards the end of 2024, as all the major news outlets reported on the death of a woman, following a routine vitamin B12 injection, which the coroner attributed to the 'failure' of the nurse to clean the injection site
Patrica Lines had attended her GP practice for a routine vitamin B12 injection in October 2023 and died six days later. The cause of death in the medical report was listed as:
Ia. Septicaemic Shock
Ib. Necrotising Fasciitis, Right Shoulder
Ic. Invasive Group A Streptococcus Pyogenes Infection
II. Type 2 Diabetes Mellitus; Ischaemic, Hypertensive and Valvular Heart Disease
The coroner asserted that the likely cause of the introduction of the Group A Streptococcus bacterium that resulted in the sepsis was the B12 injection, specifically because the skin on the right shoulder where it was given was not cleaned with alcohol prior to administration. The inquest jury concluded that the death was ‘accidental’.
Following an inquest, a coroner can issue a ‘Regulation 28 Prevent Future Deaths (PFD) report’1 to a person or organisation where the coroner believes that action to address some of the identified concerns should be taken to prevent future deaths. So, the coroner filed a PFD on the 30 October 2024,2 which asked for the Department of Health and Social Care (DHSC), NHS England (NHSE) and the UK Health Security Agency (UKHSA) to re-consider the non-use of alcohol swabs before injections to ‘prevent further deaths’. Once this reached the national papers, there was a lot of focus on the nurse who gave the injection, with the implication that she had ‘done something wrong’. For instance, The Sun3 featured this headline: “SUDDEN LOSS. Warning issued after British pensioner died days after getting a jab when nurse ‘didn’t clean her skin’”
Because of the public nature of the enquiry, patients started requesting to be swabbed with alcohol prior to injections, medical staff were questioning their practice and looking to the evidence base again. The medical discussion forums came alive with chatter and speculation about it and whether the nurse was indeed to ‘blame’, and lots of sympathy was also expressed for both the patient and the nurse. The nurse had followed the UK guidance current at the time of the injection and the chances of this happening were incredibly low.
DHSC AND NHSE RESPONSE
The DHSC kept their response brief, directing the responsibility to comment to the NHSE.4 The NHSE gave their response on 20 December 2024, delegating responsibility for a further response to the UKHSA. The NHSE5 cited the key injection technique guidance from the UKHSA policy document ‘Immunisation against Infectious Diseases’,6 more commonly known as the ‘Green Book’ (chapter 4). It also cited the more recent National Infection Prevention and Control Manual.7
NHSE also commented: ‘In Patricia’s case, it is entirely possible that this was an isolated incident, although it is difficult to comment on this without further information. The infection may have been due to factors such as commensal bacteria or external contamination, rather than a failure to clean the skin prior to injection.’5
The Green Book states: ‘Studies have shown that cleaning the skin with isopropyl alcohol reduces the bacterial count, but there is evidence that disinfecting makes no difference to the incidence of bacterial complications of injections.’6
So, both suggest that a lack of alcohol swabbing alone could not be confirmed as a sole explanation for this bacterial contamination and consequent sepsis in Mrs Lines’ death. At the time of writing, the UKHSA has yet to respond, so, currently, nothing has changed in the national guidance.
EXAMINING THE EVIDENCE
Does using an alcohol swab prior to injection really reduce infection risk? The Green Book states: ‘If the skin is clean, no further cleaning is necessary. Only visibly dirty skin needs to be washed with soap and water. It is not necessary to disinfect the skin.’6
Plenty of studies and observational data challenge the effectiveness of alcohol swabbing in reducing infection risk for routine injections. The World Health Organization (WHO) Guidance on Best Practices describes that, even without alcohol swabs, infection rates remain consistently low in various healthcare settings.8 For instance, they cite studies in vaccination clinics showing negligible differences in infection rates between those who used alcohol swabs and those who did not. WHO does, however, comment that further studies are warranted, and also highlights a distinction between vaccines and therapeutic injections, which is quite relevant in this case as vitamin B12 is not a vaccine and is indicated for treatment of B12 deficiency.
Unfortunately, the news headlines of November 2024 were unforgiving towards the nurse who administered the injection. The coroner claimed she did not use ‘common sense’, stating: ‘Common sense would seem to suggest that reducing the bacterial count would reduce the risk of bacteria being inadvertently introduced into the deeper tissues during an injection.’2
COMMON SENSE VERSUS CLINICAL RECOMMENDATION: WHERE DO WE STAND?
Healthcare professionals (HCPs) are taught to refer to evidence bases (not common sense) when making clinical judgements. One such instance might be if skin is visibly dirty. This requires a degree of judgement and if it is deemed ‘visibly dirty’ then soap and water is indicated, not alcohol swabs, according to the Green Book. Even if Patricia’s skin was visibly dirty, alcohol wipes were not indicated.
As the coroner suggested, it seems like it might be ‘common sense’ to clean skin with alcohol before an injection – the implication being that killing bacteria on the skin would lower the chances of bacterial infections. But the Green Book6 implies that while there is a valid argument that alcohol reduces bacterial count, disinfecting makes no difference to the rates or complications of infection, which is an important point.
Humans have immune systems that challenge bacterial contamination all the time. Properly trained HCPs use sterile needles and other infection control methods to reduce environmental bacteria in all clinical environments. So, any small amounts of rogue bacteria inadvertently administered at the same time as an injection will usually be dealt with by the body. Patrica Lines was 77 years old and from the coroner’s report, was living with diabetes. As a result, bacterial count on the skin could not be the only determining factor in the subsequent fatal consequences of Mrs Lines’ Strep A infection.
To know the true impact of skin swabbing, it is important to know the incidence of infections reported post-injection that can directly be attributed to injections. The authors referred to in the Green Book have suggested the study size would have to be so large to detect any sort of difference that it would be difficult to conduct. Large-scale studies isolating the effect of alcohol swabbing on injection-based infections are therefore limited. However, the data from one such observational study are reassuring.9 This study looked at patients who inject insulin. Of the 8,134,995 estimated injections among those who reported ‘never’ or ‘sometimes’ using alcohol wipes before the injections, there were 14 cases of infection reported (which equated to an incidence of 1.72 infections per million injections). Of the 1,337,045 estimated injections among those who reported using alcohol wipes pre-injection ‘often,’ ‘very often,’ or ‘always’, there were 10 cases of infection which equates to a surprisingly significantly higher incidence of 7.48 per million injections when using swabs (p= 0.001). A whole other article could be written just discussing what might have led to these findings alone, but ultimately, this implies that the use of alcohol swabs is not necessarily the most common-sense choice of the two options.
THE RISKS OF USING ALCOHOL SWABS BEFORE INJECTIONS
The coroner focussed specifically on the risks of NOT alcohol swabbing. But as with all things medical, both sides need to be considered for a balanced clinical decision.
There are risks of using alcohol swabs, as well as risks of not doing so when it comes to medicines.
Arguments against using alcohol swabs before injections
1. Scarcity of reported deaths
WHO and UKHSA guidelines indicate that alcohol swabs do not significantly lower infection risks in routine injections.6,8 Thousands of people have the very same B12 injections that Mrs Lines had, every month without incident. And when we consider other injectable medicines, there are millions of patients who have non-pre-swabbed injections every day who do not suffer fatal complications afterwards, and indeed whose lives may well have been saved by those very injections.
2. Efficiency
If we were only using ‘common sense’, the temptation might be to say ‘oh blow it, let’s just use swabs as they are only cheap’. Alcohol swabs are indeed not particularly expensive to buy, but in the huge quantities that would be needed across the NHS, the cost would certainly add up. The NHS does not have infinite resources and therefore savings would inevitably have to be made elsewhere, inadvertently taking resources away from other potentially life-saving interventions.
In general practice, what is as scarce as money, is time. Some injectable medicines, such as seasonal influenza vaccinations, need to be given to large numbers of people over a short space of time. For high-volume, time-sensitive injections such as influenza and COVID-19 vaccines, NOT swabbing can be inadvertently life-saving in itself. If routine swabbing was a recommendation, this would inevitably lead to delays in administering injections. If alcohol is allowed to dry properly (anywhere between 30–180 seconds in the literature) and a proper (30 second contact) cleanse is done, this could add up to an extra two and a half minutes to a vaccine appointment. In a busy Influenza vaccine clinic where appointments can be as little as two minutes each, swabbing routinely using the same staffing ratios could mean a 50% reduction in people vaccinated that day.
In the week ending 6 December 2024, there were 1,671 deaths from influenza, and 118 deaths from COVID-19.10 Leaving people unvaccinated or delaying vaccination is therefore also a risk to life.
3. Skin irritation and increasing chance of infection
Some people use injectable medicines regularly, for instance insulin users. The WHO guidance is indeed largely based on evidence from a large study of regular insulin users, where no clinical benefit was noted from using alcohol swabs.8 Repeated use of alcohol, especially on sensitive or frequently injected areas, can indeed lead to skin irritation and drying, which may be counterproductive for patients with ongoing injection needs. Sore, broken skin can also open up more routes to infection. Alcohol that has not been allowed to dry and is consequently tracked into the skin is not pleasant and can cause further pain and irritation. In the literature there are plenty of systematic reviews and randomised control trails exploring milder adverse events with and without swabbing.11,12 Most found no significant differences when swabbed or not, but some found increased adverse events after swabbing, such as increased or longer lasting pain (Table 1).11 However, most of these studies focus on less severe consequences and (perhaps reassuringly) do not include death as an outcome.
4. Medicinal interactions
Alcohol has potential to interact with medicines. In this case, the injection was B12 (hydroxocobalamin) injection. The Summary of Product Characteristics (SmPC) does not state whether or not the manufacturers have tested for any interactions between hydroxocobalamin and alcohol so it is unknown if there could be an issue there.13 Live injectable vaccines, however, contain attenuated viruses that must replicate in the body to build immunity. Alcohol swabs, if not allowed to dry fully, could theoretically inactivate these vaccines by damaging the live virus before injection. This risk is why in countries that do recommend an alcohol swab on occasion, such as New Zealand, official guidelines recommend waiting at least two minutes for alcohol to dry completely before administering a live vaccine or, when possible, using soap and water as an alternative for visibly soiled skin.14 WHO states specifically ‘DO NOT use alcohol for skin decontamination for administration of vaccinations’ .8 If the live Measles, Mumps and Rubella (MMR) vaccine was routinely deactivated by making alcohol swabbing a standard practice, there would inevitably be a much greater risk of death and complications from measles than there would be from ‘sepsis due to non-swabbed skin’. To give an idea of the impact of a badly-performing measles vaccine, before an effective MMR vaccine was introduced in the early 1960s, WHO estimated there were approximately 2.6 million deaths each year from measles alone.14
SO, WHERE ARE WE NOW?
HCPs should always be willing to make a change to practice when new evidence emerges and this case is certainly one that serves as a valuable cautionary tale of rare and tragic events that could potentially be associated with injections. Infection control is, after all, usually an absolute priority of anyone in a medical profession. But so far, in the absence of any further guidance from UKHSA, the safest thing to do for our patients is to stand by the best evidence that we have already.
It can easily shake the confidence of patients and staff alike when a situation like this occurs. Patients understandably may request their skin to be swabbed, and HCPs may also feel under pressure to conform to these wishes, or may be questioning their practice. But this has potential to lead them to deviate from current guidance, leaving everyone vulnerable. While this case shines a light on patient safety and serves as a good reminder of our duty of care, as HCPs it is important to allay any inconclusive or unfounded public fears about medical interventions, rather than lean into them or reinforce any potentially inaccurate assumptions.
It’s always stimulating and important to reflect on current practice when an abnormal or rare event happens that seemingly contradicts the guidance we follow. And it will be interesting to see the UKHSA response when it arrives. There are clearly arguments for and against using alcohol swabs prior to injections. While alcohol swabs have long been part of the infection control process in many clinical areas, and their use is variable around the world, evidence suggests they may not be necessary for every injection, and even detrimental on occasion. For some medicines, drying time is crucial, as alcohol could compromise the medicine’s efficacy. Efficiency in clinics must also be a factor to consider when implementing any new techniques or systems.
Before the days of evidence-based practice we might well have relied on ‘what seems the common-sense thing to do’. But common sense is not always what it might seem.
REFERENCES
1. NHSE. Action to Prevent Future Deaths reports (Regulation 28); 2024https://www.england.nhs.uk/long-read/action-to-prevent-future-deaths-reports-regulation-28/
2. Sutton R. Patricia Lines: Prevention of Future Deaths Report; 2024 https://www.judiciary.uk/prevention-of-future-death-reports/patricia-lines-prevention-of-future-deaths-report/
3. LouKou E. Warning issued after British pensioner died days after getting a jab when nurse ‘didn’t clean her skin’. The tragic death was not due to a reaction to the vaccine; 2024 https://www.thesun.co.uk/health/31450172/british-pensioner-died-days-after-getting-jab-nurse/
4. DHSC. PFD response letter; 2024 https://www.judiciary.uk/wp-content/uploads/2024/10/2024-0574-Response-from-DHSC.pdf
5. NHSE. PFD response letter; 2024 https://www.judiciary.uk/wp-content/uploads/2024/10/2024-0574-Response-from-NHSE.pdf
6. UKHSA. Immunisation Against Infectious Disease: The Green Book. Immunisation procedures Chapter 4; 2013 https://assets.publishing.service.gov.uk/media/5a7afc62e5274a34770e88e5/Green-Book-Chapter-4.pdf
7. NHSE. National infection prevention and control manual (NIPCM) for England; 2022 https://www.england.nhs.uk/publication/national-infection-prevention-and-control/
8. World Health Organization. WHO best practices for injections and related procedures toolkit; 2010 https://www.ncbi.nlm.nih.gov/books/NBK138491/pdf/Bookshelf_NBK138491.pdf
9. O’Neill J, Grinager H, Smith S, et al. Isopropyl alcohol skin antisepsis does not reduce incidence of infection following insulin injection. Am J Infect Control 2013; 41(8) 755-756. https://www.ajicjournal.org/article/S0196-6553%2813%2900023-0/fulltext
10. Office for National Statistics. Coronavirus (COVID-19); 18 December 2024. https://www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarriages/deaths/bulletins/deathsregisteredweeklyinenglandandwalesprovisional/weekending6december2024
11. Wong H, Moss C, Moss S, et al. Effect of alcohol skin cleansing on vaccination-associated infections and local skin reactions: a randomized controlled trial. Hum Vacc Immunother 2019;15(4):995-1002. https://pmc.ncbi.nlm.nih.gov/articles/PMC6605859/
12. Lafleur B, Fung J, Verschoor CP, et al. Omission of alcohol skin cleansing and risk of adverse events in long-term care residents undergoing COVID-19 vaccination: A cohort study. Hum Vacc Immunother 2024;20(1):2368681 https://pmc.ncbi.nlm.nih.gov/articles/PMC11221462/
13. Electronic Medicines Compendium. Summary of Product Characteristics – Hydroxocobalamin; 2024 https://www.medicines.org.uk/emc/product/4662/smpc#gref
14. Health New Zealand. Immunisation Handbook, section 2: processes for safe immunisation; 2024 https://www.tewhatuora.govt.nz/for-health-professionals/clinical-guidance/immunisation-handbook/2-processes-for-safe-immunisation
15. World health Organization. Factsheet: measles; 2024 https://www.who.int/news-room/fact-sheets/detail/measles