Infection control and occupational exposure

Manage now— do this, in order

• Hand hygiene by the WHO Five Moments — wash 20 seconds with soap and warm water or use alcohol rub. Alcohol rub is the default, but soap and water is mandatory when hands are visibly soiled and whenever patients are vomiting or have diarrhoea, even if gloves were used — alcohol does not kill *C. difficile* spores and poorly inactivates norovirus. Gloves are not a substitute for hand hygiene.
• Source control and respiratory protection: put a surgical mask on the coughing patient — the highest-yield single intervention; use fit-tested N95 respirators for infectious tuberculosis and high-consequence pathogens (avian influenza, MERS), and for aerosol-generating procedures a fit-tested N95, gown, gloves and face shield or goggles.
• Apply the right precaution category (see chart): contact for *C. difficile*, norovirus, undiagnosed diarrhoea and resistant organisms with bleach cleaning for *C. difficile*/norovirus; droplet for influenza, meningococcal disease, pertussis; airborne (fit-tested respirator, negative-pressure room, minimum 12 air changes/hour) for tuberculosis, measles, varicella, COVID-19. Varicella and SARS-CoV-2 need contact AND airborne. Never cohort a suspected case with a confirmed one.
• Needlestick first aid immediately: encourage bleeding gently under running water without scrubbing, squeezing hard or sucking, then wash with soap and running water; for a mucous membrane splash irrigate copiously with water or 0.9% sodium chloride, removing and discarding contact lenses first; record the time. Do not apply bleach, alcohol or caustic agents to the wound.
• Take baseline bloods from the exposed person BEFORE any prophylaxis: HIV antibody/antigen, anti-HBs and HBsAg, hepatitis C antibody — plus full blood count, renal and liver function and a pregnancy test if antiretrovirals are to be prescribed. Without a baseline, a positive result at three months proves nothing.Not available at your setup — Renal function (creatinine/urea), Liver function tests.
• Hepatitis B first — the most transmissible and most preventable: documented anti-HBs of 10 mIU/mL or more needs no prophylaxis; if unvaccinated, incompletely vaccinated or unknown, give HBIG 500 IU IM (ideally within 24 hours, effective up to 7 days) plus a full vaccine course at separate sites with separate syringes — vaccine 1 mL (20 micrograms) IM into the deltoid in adults, 0.5 mL (10 micrograms) under 16 years, anterolateral thigh under 2 years. Never into the buttock.Doctor / Nurse
• Start HIV post-exposure prophylaxis within 72 hours — give the first dose at once rather than waiting for source testing: tenofovir disoproxil fumarate 300 mg plus lamivudine 300 mg (or emtricitabine 200 mg) once daily plus dolutegravir 50 mg once daily, for 28 days. Child under 25 kg: zidovudine 4 mg/kg (maximum 300 mg) plus lamivudine 4 mg/kg (maximum 150 mg) orally 12-hourly, dolutegravir 50 mg once daily if 20 kg or more and able to swallow tablets. If only a two-drug backbone is obtainable, start it and add the third agent within 24 hours; supply an antiemetic (metoclopramide 10 mg or ondansetron 4–8 mg orally 8-hourly as required).Doctor / Nurse
• Finish the package: tetanus booster if the primary course was completed but none in the past 5 years (immunise plus tetanus immune globulin if never completed); hepatitis C has no prophylaxis, so surveillance is the intervention; serial serology for HIV, hepatitis B and hepatitis C at 6 weeks and 3 months, with hepatitis C and HIV again at 6 months if the exposed person is immune to hepatitis B or received immune globulin. Remember a negative hepatitis C antibody at four weeks means nothing — antibodies take 6–12 weeks.