Using Blood and other Material of Human Origin

The school has decided to monitor the use of Human material. A register, of all lab workers using human material and risk assessments of all procedures using human material, will be maintained by the Safety Co-ordinator. Supervisors will ensure this has been done before commencing work with human material.

Although hepatitis and HIV draws the attention of laboratory workers, there are many other diseases that may be transmitted from human or other biological material. Tuberculosis, hepatitis, enteric diseases, brucellosis and Q fever are well documented. Other agents previously unknown such as coronavirus (SARS) have appeared in recent times and there is every reason to expect others will appear.

The main routes of Laboratory Infection are by aerosol, inhalation and percutaneous absorption. Following standard safety practices can eliminate such exposure.
The basic safety principle is that all blood, blood products, body fluids and tissue are regarded as infectious and at all times are handled as if they are infected with pathogenic organisms. This is the principle of "Universal Precautions". This principle together with a good laboratory safety program and good personal hygiene are fundamental in preventing laboratory infection.

Transmission of Creuzfeldt-Jakob disease (CJD)

Only classical CJD (cCJD) has been found in Australia. Nevertheless infection control polices for cCJD provide a good basis for variant CJD (vCJD) infection control.
High infectivity tissue includes brain, spinal cord, eye, pituitary and dura mater tissues. There is no evidence that cCJD is transmitted through blood or blood products.
Exposure, in the laboratory, would most likely come from manipulating neurological tissue affected by spongioform change.
There is a theoretical possibility of infection from needlestick, contamination of broken skin, splashing on mucous membranes or ingestion.

Transmission of HIV and other Blood-borne Pathogens

Laboratory workers handling blood and other material of human origin are at higher risk of infectious blood-borne disease. In such instances OHS legislation requires that training and specific risk prevention policies and programs are in place.

Transmission of HIV

In a workplace setting, HIV virus is transmitted when infected blood or body fluids come into with broken skin or the mucus membranes of the eyes, nose or mouth.

Transmission of hepatitis viruses

• Hepatitis A, B and C differ in the way they are spread and prevented, their health effects and how they are treated.
• Hepatitis A: is spread by sewage-contaminated food and water.
• Hepatitis B & C can be transmitted, in an occupational situation, through infected blood contact with broken skin or mucus membranes, most commonly needlestick and eye splash.
  

Infection Control Program

Each research group, that uses Human material, must develop an appropriate infection control program. The required approach is to use the Risk Identification, Assessment and Control model to take into account the unique tasks, equipment and environmental situation of their laboratory.

Some questions to consider when assessing the risks are:

• How frequently is the contact with Human material?
• What are the possible transmission routes?
• Does the lab layout contribute to the risks?
• How do work systems contribute to risk?
• How do waste management procedures contribute to risk?
• What are staff/students, and their supervisors, levels of knowledge and experience and training?
• Is equipment suitable for the tasks?
• What are the available control measures?
• What type of PPE is available?
• Are appropriate vaccines or post-exposure prophylaxis available?
• Are medical and first aid services readily available?
  

Some Protective Measures to Consider

Note: The use of material of Human origin elevates the work to PC2 level (AS 2243.3:2002) and all work in that laboratory will operate at that level, unless a written risk assessment, lodged with the Safety Co-ordinator, shows the risks do not warrant this level.

The national code of practice provides that the three main steps to risk control are:

1. Developing and implementing control policies and procedures in consultation with workers.
2. Monitoring their effectiveness.
3. Reviewing policies and procedures when appropriate.
   

All controls must be designed to minimise the possibility of exposure and harm resulting from any exposure.

• Can the material be screened to confirm no infective contamination?
• Wear gowns/labcoats while working. Do not wear the gown/labcoat outside the lab.
• Wash hands, using a disinfectant hand-wash material (e.g. Bioprep) or soap (not a detergent based material e.g. Chesser Chemicals' Hand Cleaner) after completing laboratory work and when leaving the laboratory.
• Use mechanical pipettes for all liquid manipulations. Do not mouth pipette.
• Wear gloves to handle all human material or anything that has been in contact with human material. Avoid touching anything, with contaminated gloves, unless it will be disposed of or decontaminated at work completion.
• Wear safety glasses at all times when working in the lab or full face shields when appropriate.
• Cover all cuts and any other lesion on the hands or forearms with a waterproof dressing, even if wearing gloves.
• Every effort must be made to avoid touching the face, mouth or any other bare skin, with contaminated gloves. In high risk situations, or for those workers prone to unconscious face/mouth touching, a surgical mask should be worn.
• Make every effort to minimise the use of syringe needles and any other sharp implements.
• If sharps must be used: the greatest care must be taken when handling them. Never resheath needles. Dispose of all sharps into approved containers.
• All procedures, with potentially infected material, must be performed with sufficient care the prevent the creation of droplets or splashing.
• Use a biological safety cabinet (Type 2 or 1) for any procedure that can possibly create an aerosol. These include centrifuging, blending, sonicating, vigorous mixing and manipulating human tissue. Note: Cell Sorters by the mode of operation produce aerosols, potentially infective material must be properly contained when used in such a machine. (see PC2 manual and/or Using Laminar flow & Biosafety Cabinets for complete information)
• Use a sealed centrifuge for high risk material; open the sealed bucket in a biosafety cabinet. If a tube brakes autoclave the whole bucket unopened. All centrifuge tubes should be opened, after centrifugation, in a biosafety cabinet; or 20 minutes should be allowed, before opening, for settling.
• Decontaminate laboratory worksurfaces with an appropriate disinfectant (see PC2 Manual for disinfectant information) at work completion.
• Decontaminate all potentially contaminated materials used in the procedures (see PC2 manual) and dispose of all waste by autoclaving, disinfection or incineration. (see waste disposal procedures)
• Spills must be decontaminated and cleaned up immediately, see PC2 Manual for procedures.
• When transporting contaminated material special care should be taken with the containers used All material must be .
• Any instruments used for CJD work must not be mixed with other instruments at any time, to pr vent cross contamination.
• Additional Safety Practices
• Absolute security of places, where this material is stored, must be guaranteed.
• No storage or consumption food or drink is allowed in the lab or rooms opening directly on to the lab.
• To achieve the requirements of the above standards, gloves must be changed and hands washed often. This can lead, in some cases, to skin problems; the use of a skin moisturizer and the avoidance of ethanol based handwashing disinfectants (e.g. Hibiclense) is recommended.
  

Training

All laboratory Supervisors must ensure there staff and students are competent to safely carry out work with this (and all other) hazard and this competency is recorded in the School's training database. The Safety Co-ordinator can advise and help on these matters.

Vaccination and Prophylaxis

Vaccination is available for Hepatitis B, Q fever and other human pathogens. The risk assessment should have considered the matter and recorded whether the risks indicate this as necessary.
Advice on this matter is available from Chris Burrell and Graham Mayrhofer.

Accidents and Incidents

All supervisors must instruct their staff/students on the plan of action in the case of an incident. All incidents must be reported to the Safety Co-ordinator immediately, in his absence the School manager if he is also unavailable the Head of School and the University OHS Unit.