Needlestick from an HBeAg-positive source at 22:00

Local measures Wash the wound with soap and running water; allow it to bleed; do not scrub, squeeze, or apply caustic agents or concentrated antiseptic, and do not suture or cauterise. Report the injury at once so the clock starts.

Risk quantification

• Hepatitis B: the highest risk here. A percutaneous hollow-bore needle with visible blood from an HBeAg-positive, high-DNA source carries a transmission risk of up to about 30% in an unvaccinated host. Her three-dose course five years ago probably protects (seroprotection in healthy adults is 90–95% after a full course), but with no anti-HBs titre this is an assumption, not a fact.
• HIV: average percutaneous risk about 0.3%, increased by deep injury, visible blood on the device, a device that entered a vein or artery, and high source viral load. A negative rapid test three months old is not a current result.
• Hepatitis C: average percutaneous risk about 1.8%, with no prophylaxis available.

The key point Risk stratification determines urgency, not whether to act. She is a high-risk exposure and must be treated as such tonight; the unverified immune status does not justify delay.

Hepatitis B - start tonight

• HBIG 0.06 mL/kg (about 500 IU) intramuscularly, ideally within 12 hours and certainly within 24 hours, plus a booster dose of hepatitis B vaccine at a separate site.
• If her anti-HBs comes back ≥10 mIU/mL, the HBIG was unnecessary but harmless; if <10 mIU/mL she needs completion of the vaccine schedule and a repeat titre 4–8 weeks later.
• Do not wait for the titre before giving HBIG - the titre takes hours and passive immunisation is time-critical.

HIV - start tonight, within 72 hours

• A three-drug regimen for 28 days: tenofovir 300 mg + lamivudine 300 mg (or emtricitabine 200 mg) + dolutegravir 50 mg once daily. Check creatinine and do a baseline HIV test, but do not delay the first dose for either.
• Ideally the first dose is within 2 hours; efficacy falls steeply after 24–36 hours and is unproven after 72 hours.

Hepatitis C

• No prophylaxis exists. Test source and intern for anti-HCV, then HCV RNA at 4–6 weeks; if seroconversion or viraemia occurs, treat with direct-acting antivirals, which now cure over 95%.

Also Baseline sera from the intern (anti-HBs, HBsAg, anti-HBc, anti-HCV, HIV), and source HIV and HCV testing with consent.

The advice is wrong and should not be followed 'Wash it and come back tomorrow' converts a time-critical exposure into a missed-prophylaxis event. The intern should escalate immediately - night duty medical superintendent, the designated PEP nodal officer, or the emergency physician on call - and, if the kit is genuinely inaccessible, obtain HBIG and antiretrovirals from the hospital pharmacy or the nearest antiretroviral centre.

Medico-legal framework

• The employer owes a duty of care: free, promptly accessible PEP, a written sharps policy, a functional 24-hour kit, and an occupational health service. The locked cupboard is a system failure, not the intern's fault.
• Source testing requires consent and pretest/post-test counselling, with strict confidentiality; the source's identity must not be disclosed to the intern. Under national blood-borne pathogen policy, an unconscious or refusing source may still be tested on an existing specimen.
• The exposure is a reportable occupational incident and, if the source is known, a potential look-back issue for other patients.

Documentation Time of injury; device and depth; visible blood; source serology and viral load; the intern's vaccination and serology; local measures; each prophylaxis given with the exact time; the delay, its duration and who was contacted; the incident report number; and follow-up appointments at 6 weeks, 12 weeks and 6 months. A contemporaneous note is the intern's protection if seroconversion occurs.