1 Background

A needle stick injury (NSI) is defined as penetrating trauma or cut wound in the skin following accidental contact with a sharp instrument in the health care setting.¹ These sharp items include but are not limited to subcutaneous needles, blood collection needles, cannulae, needles used to connect components of intravenous administration systems and theatre instruments such as scalpels and suturing instruments.² Intravenous cannulas account for most of the NSI (33 %) and are followed by hypodermic needles (18.7 %).¹ In a study done by Alsabaani et al. a majority of NSI were due to handling/passing sharps during or after use (25.3 %) and disposal-related causes (24.2 %). Other factors such as recapping and clean-up accounted for 14.3 % and 9 % respectively.¹ NSI usually occur during administration of medication, surgical operations, blood sample collection and inappropriate needle use³

Due to the nature of their work, health care professionals (HCP) are at a higher risk of sustaining NSI(1). Around 35 million HCPs sustain NSIs annually, with 3 million being infected with bloodborne diseases.⁴ Nurses account for the highest percentage of NSI in HCPs.⁵ This is due to the fact that in most healthcare facilities, nurses carry the burden of providing direct patient care, compared to other medical professionals.⁶ In a systematic review by Abdelmalik et al. they found that 41 % of nurses experienced NSI worldwide.³ In their study, Alsabaani et al. reported that the incidence of NSI was substantially higher among those practicing surgery than any other speciality, which was in keeping with other studies in literature. They also found that the incidence of NSI in HCPs working in secondary healthcare hospitals was markedly higher when compared to their counterparts in tertiary hospitals (16.3 % vs. 10.1 %).¹

In their systematic review of NSI in 35 countries, Abdelmalik et al. noted that the prevalence of NSIs varies from country to country. The highest NSI rate was found in Ghana (70 %). In the United States (US), the NSI prevalence was 26.3 %, 39.18 % in China, 47.85 % in Iran and 51.73 % in Egypt.³ In a study by Yazie et al. the NSI prevalence in Ethiopia was reported to be 43.6 %,⁷ which was similar to those in studies from India between 40 % and 45 %.^3,8 Prevalence of NSI was 46.0 % in both Nigeria and Saudi Arabia.⁹ The incidences and prevalence of NSI are 90 % higher in developing countries compared to developed countries.¹⁰ This can be highlighted by the difference between the NSI prevalence of 37.0 % in the United Kingdom (UK), compared to 70.3 % in Nepal, a developing country.^11,12 The lower NSI prevalence in developed countries can be ascribed to proper implementation of hospital-level NSI prevention programs, establishment of training courses and establishment of a preventative perspective on NSI among HCPs.¹³

Despite the higher incidences and prevalences stated above, the centers for disease control and prevention (CDC) reports that almost half of NSIs among HCPs go unreported.¹⁴ Reasons for under-reporting of NSI in HCPs include forgetting, not knowing how to report, underestimating the danger NSI pose, reluctance to disclose their lack of knowledge on the proper use of tools, anxious about a positive serology test result and being too busy.^1,15–17

2 Bloodborne infections from NSI

NSI are a major source of infection with bloodborne disease such as Hepatitis B Virus (HBV), Hepatitis C Virus (HCV), and Human immunodeficiency Virus (HIV).¹⁸ The risk of transmission following percutaneous exposure to infected blood is 2–40 % for HBV, 2.7–10 % for HCV and 0.3 % for HIV.¹⁹ NSIs are responsible for 39 % of HCV, 37 % of HBV, and 4.5 % of HIV infections among HCPs.²⁰

According to the HIV and Acquired Immunodeficiency syndrome (AIDS) statistics by joint United Nations program on HIV/AIDS (UNAIDS), the global prevalence of HIV in 2022 was 39 million. Africa carries the highest burden of disease, accounting for 66 % (25.6 million) of the global prevalence.²¹ Western and Central Europe and North America pale in comparison, as they only account for 0.06 % (2.3 million) of the global prevalence.²¹ HIV is a member of the lentivirus genus of the Retroviridae family,²² and it is made up of two copies of positive single-stranded ribonucleic acid (RNA) enveloped by nucleocapsid protein²³. HIV is mostly transmitted through sexual contact. Other less frequent routes of transmission include NSI, Intravenous drug use, exposure to infected blood and blood products during transfusion, and exposure to fetus or infant from an infected mother.²⁴ Upon entry into the bloodstream, HIV enters cells through interaction with the CD4 receptor and a chemokine co-receptor (CXCR4 or CCR5) which are expressed on cell membranes of about 60 % of circulating T-lymphocytes, on T-cell precursors in the bone marrow and thymus, on monocytes/macrophages, eosinophils, dendritic cells and microglial cells of the central nervous system. This is followed by the HIV replication cycle which leads to viremia and disease progression.^24,25

The global prevalence of HBV and HCV are 296 million and 58 million people respectively, resulting in 1.1 million deaths annually.²⁶ In the healthcare setting, HBV and HCV are mostly transmitted through percutaneous or mucosal exposure of HCPs to body fluids and blood from infected patients. NSI is the most common cause of infection in HCP.²⁷

HBV is an enveloped, hepatotropic DNA virus that belongs to the hepadnaviridae family.²⁸ Following entry in the blood stream, it infects and replicates mainly in the hepatocytes. This results in acute, self-limiting illness followed by viral clearance, in rare fulminant cases, it can lead to liver failure.²⁹ Chronic HBV is characterized by ongoing low-grade hepatitis, with episodes of transient high-grade liver inflammation and activation of fibro-genic process, resulting in liver fibrosis and cirrhosis which may culminate in symptomatic liver disease and/or hepatocellular carcinoma (HCC).²⁹ Hepatitis C is an RNA virus that belongs to the Flaviviridae family. Following acute infection, HCV can lead to acute hepatitis. In 50–80 % of patients, it progresses to chronic hepatitis C. Chronic HCV precipitates a chronic inflammatory disease process, which may result in liver fibrosis, cirrhosis, HCC and ultimately death.^30–32

3 Risk factors

Needle stick injuries/incidents (NSIs) are one of the most common preventable occupational hazards among healthcare workers.³³ Several studies have been conducted among healthcare workers in different parts of the world, and similar risk factors were identified in most of them. There is conflicting evidence with an association between work experience and needle stick injuries among healthcare workers.³⁴

Identified factors that are related to needle stick incidents include the lack of PPE, inadequate experience, long working hours, occupation of the healthcare worker, low level knowledge about the risks of NSIs, and the work technique (recapping of needles, patient movement during phlebotomy, or administration of IV or IM drugs.³³ These injuries commonly occur on fingers and is common in surgical disciplines.^33,35,36 Other factors have been attributed to failure to observe universal precautions, excessive fatigue and job stress due to long working hours, overuse and unnecessary use of sharp instruments.^33,35,37

In a systematic review of needle stick injuries among healthcare workers, it was identified that these injuries are attributed to three major factors: engineering factors, which is the form of sharp or barrier devices; organizational factors, the existence of supplies and policies for reporting; and behavioural factors, which is recapping and disposal-related issues.^34,38 A study conducted among nurses in Sub-Saharan Africa found that 40 % of the NSIs were related to administration of injections, about 16 % to the disposing of used needles, and approximately 13 % to the recapping and suturing, and cleaning after patient care.³⁶ In another study done in a tertiary hospital in Pakistan, injecting medicines and drawing blood (42 %), followed by two-handed recapping of needles (37 %) were also found to be the leading causes. Overall, it was found that healthcare workers had inadequate practices regarding precautions such as availability of PPE (40 %) and infection control guidelines/protocols (10 %) in their working environments 937).

A total of 2260 healthcare workers were selected for a study in Menouf University Hospital in Egypt. An analysis done revealed that the risk factors for NSIs included duration of working <15 years, being female, working as a paramedic, surgical ward, >2 night shifts, absence of training on prevention strategies and firm hospital policies & universal measures, recapping with two hands, and not wearing PPE.³⁸ In a study done in USA among surgical residents (699), and published in the Journal of Vascular Surgeons, it was found that 83 % had a needle stick injury during training. The number of incidents increased according to the years of training and 99 % of the residents had reported at least one incidence. In the injuries reported, a high-risk patient was involved in 53 % of them. Approximately 51 % were not reported due to lack of time being the reason in 42 % of the unreported cases. 67 % of the injuries were self-inflicted, and 33 % being inflicted by another member of the operating team. About 52 % of the injuries occurred during suturing, with the perceived cause being in a rush in 57 % of them.³⁹

4 Diagnosis

The transmission risk of HIV infection secondary to occupational exposure varies greatly based on the type and severity of the exposure. Needle stick injuries are broadly categorized as a “sharps” injury which requires the percutaneous inoculation by a contaminated device from an infected source. Literature describes a higher HIV transmission rate in association with the following: i) deeper subdermal sharp injury ii) percutaneous trauma with a hollow needle that had previously penetrated an artery or vein iii) blood visible on the sharp iv) confirmed HIV subject v) higher volume of inoculated blood.^40–42 Healthcare Worker (HCW)-related factors may also contribute to the risk of infection: integrity of the skin barrier, immunological status and hygiene practices.⁴³

Some of the earliest studies focused on HIV transmission risk from percutaneous clinical exposure include a prospective cohort study on 1344 HCW over a 6-year period with a mean follow up of 30.2 months.⁴³ Seroconversion was reported as 0.56 % with occupational exposure. Furthermore, results from this study were combined with other prospective studies and the risk of HIV-1 transmission through percutaneous exposure to blood was estimated to be 0.3 % per exposure (95 % CI).⁴³ Similar statistics were produced in a 1996 CDC surveillance project with aggregated data from 23 studies.⁴⁴ The 0.3 % estimate represents an average for any clinically related percutaneous HIV transmission, however, there are subdivisions of exposure which are lower or higher than this estimate.^43,44

In the era of timely Post-Exposure Prophylaxis (PEP) initiation and increasing viral suppression in patients with HIV, the risk of transmission is likely lower than previously stated. Thus, data reviewing seroconversion rates in HCW after percutaneous exposure to HIV has become dated - authors of 13 year prospective study in the University of Pittsburgh aimed to determine more current trends in seroconversion. The study found a 0 % seroconversion rate after both percutaneous and cutaneous exposure. Additionally, a literature review found 17 articles with similar study parameters and the merged results demonstrated an overall seroconversion rate of 0.13 %.⁴⁵ These results suggest that HIV is no longer as easily transmissible from sharps or needle stick injuries. To further support these findings, a cross sectional study in Mexico from 2015 to 2024 on 514 HCW found a 0 % seroconversion rate which can be attributed to timely PEP initiation.⁴⁶

Every person who presents with a suspected sharp/needle stick injury should be assessed by a healthcare professional. The HIV status of the source-individual should be determined (with informed consent), the site of injury should be examined for evidence of damage to the epidermis, and the site of injury must be thoroughly irrigated and washed with soap.⁴⁰ Performing tests on the sharps or needles is not recommended as results yielded are unreliable. The recommended routine investigations which are to be performed on an exposed individual (>2 years of age) are as follows: 1) Baseline: Rapid test + 4th generation HIV ELISA; 2) 6 weeks: 4th generation HIV ELISA; 3) 3 months: 4th generation HIV ELISA.⁴⁰

HIV-1/2/Ag/Ab combination immunoassay testing should be done in conjunction with PEP initiation however, no later than 72 h post exposure and ideally within 2 h. The effectiveness of PEP (its time-dependent efficacy) has been evidenced in animal model studies. Both Tsai and Otten found lower rates of HIV infections the sooner PEP was started on animal subjects and noted that >48–72 h yielded higher rates of breakthrough plasma viremia regardless of PEP initiation.^47,48

5 Management

6 Current literature recommendation

Post exposure prophylaxis (PEP) was developed in response to occupational exposure to HIV in the 1980s.⁶⁰ The first set of guidelines were developed by the Centers for Disease Control and Prevention in 1990.⁶⁰ Post exposure prophylaxis for HIV should be offered to individuals with proven or suspected exposure to the pathogen.⁶¹ Guidelines were made available by the WHO in 2014, which were subsequently updated in 2018.⁶¹ In 2014, a standard of three-drug therapy was used as PEP, where only two drugs available, it was suggested they were taken immediately after exposure with addition of the third drug if it became available ⁶¹. In the updated 2018 guidelines, the WHO recommended the use of Tenofovir (TDF) + Lamivudine (3 TC) or Emtricitabine (FTC), and new drug Dolutegravir (DTG) as the preferred third drug.⁶¹ The use of a fixed combination TLD (TDF+3 TC + DTG) is preferred because it decreases the pill burden and thus increases compliance ⁶¹. The recommended duration for this regimen is 28 days.⁶¹

A high level of commitment to the pre-exposure prophylaxis (PrEP) regimen is required for it to be effective.⁶² With adherence, PrEP is highly effective in preventing HIV acquisition in at risk individuals ⁶¹,⁶². Currently, two modalities exist for PrEP.^61,62 The oral regimen involves taking two drugs, TDF/TFC or alternatively TDF/3 TC.^61,62 A new long acting cabotegravir injectable (CAB-LA), which is administered every two months, can also be used.^8,11 CAB-LA demonstrated superiority over the oral regimen, based on the outcomes of clinical trials HIV Prevention Trials Network (HPTN) 083 and HPTN 084.⁶²

7 Outcomes of PEP

The adherence and completion rates of post-exposure prophylaxis (PEP) are reported to be 78 % overall after four weeks.^1,63 Despite the 28-day therapy period being founded on limited animal research and expert opinion, patients should comply with it.^5,63 In a study involving 266 healthcare workers who experienced needle stick injuries and exposure to HIV-contaminated body fluids over a 13-year period, the seroconversion rate was found to be 0 %.^5,63 Most institutions presently make arrangements for a complete course of PEP drugs at no expense to the employee, which improves outcomes and effectiveness of the treatment.^5,63 Early post-exposure prophylaxis (PEP) provided 12–36 h post-exposure demonstrates superior efficacy in animal models compared to PEP administered 72 h later.^5,63 Timely support and counselling are essential for minimizing anxiety, ensuring PEP adherence, and achieving optimal outcomes.^6,64 Potential mental health concerns that should be addressed during counselling encompass major depression, anxiety, attention deficit hyperactivity disorder, post-traumatic stress disorder, and psychotic disorder, as these have been observed in over 50 % of participants who experienced at least one of these conditions.^7,65

8 Complications of PEP

Adverse effects of medication: all Antiretroviral Treatments may induce adverse effects, which must be thoroughly evaluated and discussed prior to initiating PEP. Short-term adverse effects include cutaneous rash, nephrolithiasis, insomnia, concentration problems, depression, digestive intolerance, and malaise.^1,2,66,67 The primary consequence arises from the HIV post-exposure prophylaxis (PEP) medications, which are not life-threatening.^3,68 Patients with HIV seroconversion face elevated chances of significant consequences if untreated, perhaps resulting in AIDS.^4,69 Acute kidney injury associated with Fanconi’s syndrome has been documented in patients receiving HIV postexposure prophylaxis with tenofovir disoproxil fumarate.^8,70

9 Conclusion

Needlestick injuries carry the greatest risk for disease transmission, particularly the hepatitis B virus by percutaneous exposure to sharp instruments, followed by the hepatitis C virus and less risk for human immunodeficiency virus. The treatment strategies of needlestick injuries have advanced throughout the years, particularly for HIV post-exposure prophylaxis, exhibiting low adverse effects in patients. Surgeons are obligated to use preventative measures during operations, reduce occurrences of on-duty injuries, and comply with treatment protocols.

Numerous concerns remain unanswered following this review: Should post-exposure prophylaxis (PEP) continue for 28 days after the introduction of new medication treatment strategies? Should the viral load of the source influence the duration of post-exposure prophylaxis (PEP)? What is the recommended strategy for a novice surgeon following a needlestick incident after commencing a private practice?

CRediT authorship contribution statement

Collen Sandile Nkosi: Conceptualization, Methodology, Writing – original draft, Writing – review & editing. Lunga Gadala: Conceptualization, Methodology, Writing – original draft, Writing – review & editing. Refilwe Mahlodi Ledwaba: Conceptualization, Methodology, Writing – original draft, Writing – review & editing. Rejoice Jorokee Katjitae: Conceptualization, Methodology, Writing – original draft, Writing – review & editing. Cry Mabaso: Conceptualization, Methodology, Writing – original draft, Writing – review & editing. Yenziwe Sibongokuhle Mbambo: Conceptualization, Methodology, Writing – original draft, Writing – review & editing.

Ethic statement

No ethnical approval was needed for this review.

No guardian

No guardian/patient consent was needed for this study as this study was a retrospective review.

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.