How to deal with an exposure incident

This section of the guidance is aimed at helping those involved in the initial management of the incident, to determine whether onward referral to such professional advice is necessary. The term 'source' means the person/item from which the blood or body fluid originated, whilst the term 'recipient' means the person exposed to potentially BBV infected blood or body fluids.

Employees

What should I do?

• familiarise yourself with the immediate first aid requirements.
• report incident to your supervisor, line manager or health and safety advisor and your occupational health department.

Employers

Employers are legally required to undertake emergency planning^[26] as part of their employer responsibilities.

• Sources of authoritative guidance
• Immediate first aid requirements
• Incident evaluation
• Risk of transmission of blood borne viruses from patient to health care worker with intervention

Sources of authoritative guidance

Authoritative information sources related to BBV post exposure intervention and treatment:

• Expert Advisory Group on Aids (EAGA) issues specialist guidance on HIV post-exposure prophylaxis, which can be found at. HIV post-exposure prophylaxis: guidance from the UK Chief Medical Officers' Expert Advisory Group on AIDS^[27];
• National guidance is available in the following publication to aid the management of healthcare workers exposed to a hepatitis B infected source patient, including the use of hepatitis B vaccine and immunoglobulin: PHLS Hepatitis Subcommittee. Exposure to hepatitis B virus: guidance on post-exposure prophylaxis. Communicable Diseases Review 1992;2:R97-R100. This is available at Communicable Disease Report - Exposure to hepatitis B virus: guidance on post-exposure prophylaxis;
• Extracts of this guidance are also reproduced in from Immunisation against infectious disease, Hepatitis B, Chapter 18, The Green Book (DH). At: Department of Health - Immunisation against infectious disease - 'The Green Book'^[28];
• Full details on the required follow-up for healthcare workers exposed to hepatitis C can found in the following publication:  Guidance on the investigation and management of occupational exposure to Hepatitis C, ME Ramsay. Communicable Disease Public Health 1999; 2: 258-62. Available at: Guidance on the investigation and management of occupational exposure to hepatitis C;^[29]
• Under exceptional circumstances, eg where multiple casualties exist, specialist post exposure action may be required for those exposed to the blood and tissue of others. Advice is available at: Department of Health - Post exposure prophylaxis against hepatitis B for bomb victims and immediate care providers. Consideration of other blood borne viruses (hepatitis C and HIV).^[30]

Immediate first aid requirements

• Where the eyes or mouth have been exposed to blood or body fluids, they should be washed copiously with water.
• For puncture wounds, the wound should be gently encouraged to bleed, but not scrubbed or sucked, and should be washed with soap and water.

It is not necessary to keep any needle/sharp instrument to send to the laboratory for testing for the presence of blood-borne viruses. Any such sharp instruments should not be re-sheathed, but disposed of directly into an appropriate container.

Incident evaluation

An urgent risk assessment is required to establish if the exposure has the potential to transmit a blood-borne virus – ie, whether or not the exposure is significant. A number of factors will be taken into account in the risk assessment, including:

• the type of body fluid to which the recipient has been exposed - Blood carries the highest risk, but BBV can be transmitted by other body fluids, especially if they are also contaminated by blood.

• Route of exposure - This is classified essentially into 3 categories - percutaneous, mucous membranes (which include eyes, mouth), and skin. Splashing of blood/body fluids onto mucous membranes may result in virus transmission, although the risk is considerably lower than for percutaneous exposure:
  • if intact, skin is impervious to these 3 viruses; however,
  • if the skin is not intact eg, through cuts or abrasions, or chronic dermatitis such as eczema, then transmission may occur;
• Nature of exposure - An assessment should be made as to whether exposure to blood/body fluids was direct, or indirect, eg through an item, such as a contaminated device or instrument.
  • If indirect, then in what way had the item become contaminated? Contaminated hollow bore needles (eg those used for injection) are more likely to transmit than solid needles (eg those used in suturing);
  • Needles that have been present in a blood vessel are more likely to transmit than needles used for intramuscular injection;
  • How soon after the sharps became contaminated did the exposure incident occur? The viability of the BBV will decrease rapidly on drying, so, for instance, transmission is very unlikely from a dried-up needle found lying in a field;
• Personal protective equipment (PPE) used - eg, were gloves in use? There is a wiping effect as a needle pierces a glove, which may reduce the likelihood of transmission.
• What is known about the source?
  • If the source is known, it may be possible to determine their BBV infection status, or the presence of risk factors for BBV infection, from serological testing with informed consent or from medical notes; and
  • if the incident arose from an unknown source, a risk assessment may still be possible in the light of local knowledge of the prevalence of BBV infections.
• Hepatitis B immunisation status of the recipient - has the recipient previously received any doses of HBV vaccine? If so, was he/she a responder to the vaccine?

All of the above will contribute to decisions on whether HIV and/or HBV post-exposure prophylaxis (PEP), or follow-up for evidence of HCV transmission, is required.

Risk of transmission of blood borne viruses from patient to health care worker

**There is a wide variability in infectiousness of hepatitis B carriers.  The risk stated is that of transmission following needlestick exposure in unvaccinated individuals.