NUMBERS OF STAFF ON SHORT-TERM CONTRACTS AT THE BBSRC-SPONSORED INSTITUTES

Total number of scientific staff at the institutes split by staff on indefinite contracts and those on period contracts for the last five years.

"AVIAN INFLUENZA"

  This memorandum has been prepared by HSE in consultation with the Department of Environment, Food and Rural Affairs (Defra) and the Department of Health.

Question 1: what is the difference in requirements for level 3 and level 4 pathogen containment facilities and identifying which would be required for the avian flu virus, should it mutate to become transmissible between humans?

  Containment requirements for laboratories working with highly pathogenic avian influenza viruses (including strain H5N1):

  1.  Work with highly pathogenic avian influenza viruses (including strain H5N1) must be adequately contained to protect human health and the environment. As such it is subject to both the Specified Animal Pathogens Order 1998 (SAPO), administered by Defra, and the Control of Substances Hazardous to Health Regulations 2002 (as amended) (COSHH), administered by HSE.

  2.  Containment under SAPO is primarily concerned with preventing the escape of pathogens from a laboratory into the environment. Containment under COSHH is primarily concerned with protecting workers and preventing spread into the wider community.

  3.  The key containment measures are set out below.

  4.  For worker protection, the Advisory Committee on Dangerous Pathogens (ACDP) has recommended that HPAIs, including H5N1 and strains that may have originated from human infections, should be handled at ACDP containment level 3 (ACDP CL3).

  5.  However, whilst HPAIs can cause human disease, they are still primarily pathogens of birds. The serious consequences of an accidental release into the environment, means that these strains are categorised as requiring the highest level of containment under SAPO—containment level 4 (SAPO 4).

  6.  As there is a difference in the recommended containment levels, users must apply the higher of the two standards. This means that laboratories working with HPAIs must meet the full requirements of SAPO 4, which should also be sufficient to protect human health.

Question 2: what would be required for the avian flu virus, should it mutate to become transmissible between humans?

  7.  Should a HPAI mutate to become transmissible between humans, the approach to containment would have to be reviewed according to the circumstances. For example, if human-to-human transmission was seen in the Far East, and the virus had been restricted to particular areas (as happened with SARS), containment of clinical samples being brought into UK laboratories would need to be maintained at a high level (SAPO 4) to ensure that work activities did not lead to the introduction of the virus into the environment or the UK population.

  8.  During the first stages of any human pandemic (ie before a strain is routinely circulating in the UK), HSE has developed a strategy based on advice from ACDP that all intentional work with such viruses should be carried out at ACDP CL3.  However, once the virus is the predominant circulating strain and a vaccine is available, it could be handled at ACDP CL2.  Under these circumstances, containment requirements under SAPO would also be reduced. A system of derogations from SAPO 4 has been agreed between Defra and the Health Protection Agency, whose laboratories would be carrying out the diagnostic work on clinical specimens.

  Key containment measures under SAPO 4 and ACDP 3:

SAPO level 4

  The key measures are:

—  The laboratory must be mechanically ventilated, with the input air being passed through a High Efficiency Particulate Filter (HEPA) and extract air passing through double HEPA filters.

—  The laboratory must be maintained at a negative pressure with respect to atmosphere of at least -75 Pascals.

—  The laboratory must be sealable to permit fumigation.

—  Entrance into the laboratory is restricted to trained personnel, who must enter and leave through an airlock, and must shower before leaving.

—  All work with live pathogens must be carried out in a microbiological safety cabinet.

—  All waste must be sterilised before leaving the laboratory, by passing through a double-ended autoclave.

ACDP level 3

  The key measures are:

—  The laboratory must be mechanically ventilated, with the extract air passing through a single HEPA filter.

—  The laboratory must be maintained at negative pressure with respect to atmosphere (pressure not specified, but guidance recommends -30 to -50 Pascals).

—  The laboratory must be sealable to permit fumigation.

—  All work with live pathogens must be carried out in a microbiological safety cabinet.

—  Entrance into the laboratory is restricted to trained personnel.

ACDP level 2

  The key measures are:

—  Entrance into the laboratory is restricted to trained personnel.

—  Aerosol generating procedures with viable organisms must be carried out in a microbiological safety cabinet.

—  The laboratory benches should be of a suitable quality and easy to clean.

—  Waste should be disposed of safely.

December 2006