Biological agents are living things, or products of living things, that can
cause illness and disease in humans. Biological agents include viruses, bacteria
and fungi, as well as parasitic worms and some plants.
Biological agents enter the body when they are inhaled, eaten (ingested) or
absorbed. Most biological agents are inhaled. Once inside the body, these
infectious agents can multiply quickly and may be passed from one person to
another. Some can survive outside the body for a quite a long time if they have
the right breeding ground, such as water or food. Others die quickly without the
protection of the body.
Some infectious agents are transmitted directly:
|•||through physical contact between an
infected and non-infected person
|•||when droplets are projected, by a cough
or a sneeze, into the mucous membranes of another person’s nose, eyes or
|•||when a person is injected or punctured
by an infected object, such as a needle
Other infectious agents are transmitted indirectly:
|•||by attaching themselves to food,
water, cooking or eating utensils
|•||when an insect carries them from an
infected to a non-infected person
|•||through the air, where they can be
Health effects of biological hazards
Biological agents that are capable of causing disease are known as pathogens.
People who work with animals or plants, or in health and child care are most at
risk for biological hazards. People who work with ventilation systems, municipal
sanitation or sewage operations are also at increased risk.
Common diseases caused by biological agents:
|•||bacterial diseases, such as
tuberculosis, tetanus, food poisoning and blood poisoning
|•||fungal diseases, such as ringworm and
|•||viral diseases, such as mumps,
hepatitis, German measles, West Nile Virus
|•||parasitic worms that enter the body
when their eggs are ingested
Controlling biological hazards
The best way to prevent illness is to reduce or eliminate exposure to biological
agents. Here are some tips to protect yourself against infection:
|•||Practice good personal hygiene (e.g.
regular hand washing) – it’s one of the best ways to prevent the
transmission of infection.
|•||Keep your immunizations up-to-date.
|•||Ensure that any equipment that might
harbour bio-hazards (e.g. fans, ventilation systems) is regularly
maintained, cleaned and sterilized.
|•||Clean and disinfect work surfaces
|•||Clean up spills immediately.
|•||Handle and dispose of all bio-hazardous
waste materials safely.
Blood and any other bodily fluids should always be handled as if they could
be infectious. In the event of an injury or bleeding, every
individual should be handled in a way that minimizes exposure to blood and
|•||Wear personal protective equipment
(e.g. gloves, masks), where appropriate.
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