Needlestick Injury

Needlestick injury is a percutaneous or mucosal exposure to blood or body fluid from a needle or sharp, with a risk of transmission of hepatitis B, hepatitis C and HIV. Prompt first aid, risk assessment and post-exposure prophylaxis reduce the risk of infection.

Settings. Healthcare, dental and laboratory work, cleaning and waste handling, emergency and police work, and tattooing. Injuries occur during recapping, disposal and procedures.

Transmission risk. About 6 to 30% for hepatitis B in non-immune people, depending on source e antigen status. About 0.2 to 1.8% for hepatitis C. About 0.3% for HIV from percutaneous exposure and about 0.09% from mucous membrane exposure.

Factors raising risk. Deep injury, visible blood on the device, hollow bore needle that was in a vein or artery, large volume, and a source with high viral load or advanced HIV.

Other infections. Rarely other bloodborne agents, including syphilis, malaria and viral haemorrhagic fevers.

Pathophysiology.

Virus in blood enters through the break in skin or mucosa and infects hepatocytes (hepatitis B and C) or CD4 cells (HIV). Early antiviral therapy and immunisation can prevent establishment of infection.

HIV prophylaxis works best within hours of exposure, because the virus replicates locally before spreading to lymph nodes.

• Injury at the time: puncture or cut with bleeding, or splash to eye, mouth or broken skin.
• Infection is usually silent early. Acute hepatitis B or C presents with jaundice, fatigue and abnormal liver tests after 4 to 12 weeks. Acute HIV seroconversion causes fever, rash and lymphadenopathy after 2 to 4 weeks.

High risk features.

• Deep injury with a visibly bloodied hollow bore needle from a vein or artery.
• Source known to be HIV positive with detectable viral load, or hepatitis B e antigen positive.

• Record time, device, depth, fluid, injury type and the worker's vaccination status.
• Worker baseline: HIV antigen and antibody, hepatitis B surface antigen, anti-HBs and anti-HBc, hepatitis C antibody and ALT, creatinine and pregnancy test where relevant.
• Source testing with consent: HIV, hepatitis B surface antigen and hepatitis C antibody, with HIV viral load or hepatitis C RNA when positive. Do not delay prophylaxis for source results.
• Follow up testing: HIV at 6 and 12 weeks; hepatitis C RNA at 3 to 6 weeks and antibody at 3 to 6 months; hepatitis B markers at 6 months in non-immune workers.

• First aid at once: encourage bleeding, wash the wound with soap and running water, and do not suck or scrub. Irrigate eyes or mouth with water or saline. Do not use bleach or antiseptics in the wound.
• Assess the risk and start prophylaxis the same day where indicated.
• HIV prophylaxis: tenofovir disoproxil fumarate 300 mg with emtricitabine 200 mg orally once daily (one fixed dose tablet) plus dolutegravir 50 mg orally once daily, started as soon as possible, ideally within 2 hours and not later than 72 hours, for 28 days. Maximum one tablet and 50 mg dolutegravir daily (dolutegravir 50 mg twice daily with rifampicin). Monitor adherence, creatinine and ALT at baseline and at 2 weeks. Take dolutegravir 2 hours before or 6 hours after antacids, calcium or iron, or together with food. Avoid with dofetilide and limit metformin to 1 g daily. When creatinine clearance is 30 to 49 mL/min give the combination every 48 hours, and under 30 mL/min use an alternative regimen by specialist advice. Stopping tenofovir in a person with hepatitis B can cause a hepatitis flare.
• Hepatitis B: no action for workers with anti-HBs of 10 mIU/mL or more. For non-immune workers give hepatitis B vaccine (20 micrograms intramuscularly into the deltoid) at 0, 1 and 6 months, or 0, 1 and 2 months with a booster at 12 months, and hepatitis B immunoglobulin 500 IU intramuscularly as a single dose within 48 hours (up to 7 days) when the source is positive or unknown and high risk. Check anti-HBs 1 to 2 months after the last dose.
• Hepatitis C: there is no prophylaxis. Detect infection early by RNA testing and refer for direct acting antiviral treatment by a hepatology or infectious diseases specialist, since early treatment cures nearly all.
• Tetanus immunisation by status.
• Counselling: safer sex or barrier use and avoidance of blood donation and pregnancy until follow up testing is complete; psychological support.
• Prevention: safety engineered devices, no recapping, sharps bins within reach, hepatitis B vaccination of all at risk workers, and training and incident reporting.

Monitoring. Adherence and adverse effects at 2 weeks; serology as set out in Diagnosis; symptom review for seroconversion illness.

Referral and escalation. Occupational health or emergency department at once, within hours; infectious diseases or hepatology specialist for any positive result or when the source is high risk; incident reporting, workplace investigation and compensation where required.

Special groups. Pregnancy: dolutegravir based prophylaxis, hepatitis B vaccine and hepatitis B immunoglobulin are acceptable. Breastfeeding workers need advice during follow up.