Immunisation

In the COSHH hierarchy of control measures, immunisation as protection against infection at work is the last line of defence and other controls should be available. However, for workers potentially exposed to blood-borne viruses, such as healthcare and biomedical laboratory staff, immunisation is an appropriate additional measure.

In simple terms, this approach uses the following principles, and in the following order of consideration:

Under COSHH requirements:

• If a risk assessment shows that there is a risk of exposure to biological agents, and effective vaccines exist, then provision should be made to determine whether an employee is already immunised, and immunisation should be offered to those not already immunised. The pros and cons of immunisation/non-immunisation should be explained when offering immunisation to the worker at risk.
• Under the Health and Safety at Work etc Act, employers must pay for protective measures such as immunisation. Where practical, this is likely to be provided through the company occupational health provider. Alternatively, the employee could be asked to arrange immunisation through their own GP, but the employer must make alternative arrangements if this cannot be done, and reimburse any charges made to the employee for such arrangements.

As with all control measures, immunisation needs to be checked and reviewed and boosters provided where deemed necessary.

Department of Health Green Book immunisation guidance

Final decisions on immunisation should be made on the basis of a local risk assessment. In settings where the workplace task is likely to lead to significant exposures on a regular basis (eg biting), the DH Green Book indicates that it would be prudent to offer immunisation to staff even in the absence of documented HBV transmission.

A safe and effective vaccine for the prevention of hepatitis B infection is available, and any requirement for it will be determined as part of the risk assessment described previously. Further details are available from the DH Green Book.

Pre-exposure immunisation against HBV is strongly advised for all workers who may be exposed to blood, body fluids or tissues as part of their work activity. Within the Green Book, the UK Department of Health identifies those workers who are at increased risk, and recommends immunisation.

Advice on schedules for vaccine administration, assessment of response to immunisation, management of non - and sub-optimal responders to vaccine, and the requirement for booster doses is also provided in the DH Green Book.

There are currently no vaccines available against hepatitis C or HIV, although there are measures that can be taken following exposure, which may prevent the development of infection.

Employer responsibilities

The risks from exposure to BBV must be assessed under COSHH Regulations, and appropriate measures to protect workers and others from infection risks must be implemented. The provision of routine pre-exposure immunisation may be appropriate in certain cases, eg in exposure prone occupations, for those not already immune. Employers need to be able to demonstrate that an effective employee immunisation programme is in place, and they have an obligation to arrange and pay for this service. It is acknowledged that some exposure prone workers may choose not to have the immunisation.

Health and safety law requires that employees shall not be charged for vaccines offered as means of protecting them at work. In providing vaccines, employers should ensure that employees are made aware of the advantages and disadvantages of immunisation and its limitations. Occupational health records should be kept updated of any immunisation course(s) undertaken. Employees are at liberty to refuse immunisation, but any refusal should be considered as part of the risk assessment.

Additional controls may still be necessary, particularly since immunisation is currently only effective against HBV, and should therefore be considered as part of the risk assessment of work assigned to the individual. Any exposure-prone work should only be undertaken when all work activities and their potential for BBV exposure have been assessed in this way, and the necessary controls are in place.

Under the COSHH regulations, individual workers have the right to know whether or not they have been protected by immunisation and their employers need to know if the vaccine has been effective following it. Consideration is required of how information on immunisation is communicated to managers, while maintaining medical confidentiality for the individual.

The Association of NHS Physicians (ANHOPS) has considered this issue. Their guidance on the immunisation of healthcare staff states that individual consent should be obtained from each health worker, to allow transference of their immunisation status - or protection/not protected status - to deploying managers. With such information available to them, the deploying manager can also be made aware when immunisation reviews are necessary (eg booster dose of Hepatitis B vaccine). It is important to note that, in addition to immunisation, the COSHH regulations require that other control measures are put in place to prevent and control exposure to BBV for those workers involved in exposure-prone procedures, as described previously.