Classes of Infectious Micro-organisms

Classes of Infectious Micro-organisms

1. Risk Group 1 (RG1): agents have the lowest individual and community risk and include agents that rarely cause infection in healthy hosts.

   • laboratory strains of non-pathogenic E. coli, S. cerevisiae, soil micro-organisms.

2. Risk Group 2 (RG2): agents that may cause disease in healthy hosts, but are difficult to transmit, don’t usually cause serious or life-threatening illness and are readily treated or prevented.

   • pathogenic E. coli, Campylobacter spp, Plasmodium spp, prions, HIV (infected blood only).

3. Risk Group 4 (RG4): agents are those that present significant individual and community risks and usually produce life-threatening disease, are readily transmissible and effective prevention and/or treatment are not usually available.

   • Ebola, Hendra and Nipah viruses.

4. Risk Group 3 (RG3) agents are those that usually cause serious disease and may present a serious risk to laboratory workers. A Risk Group 3 agent may also present significant community risk if spread in the environment, but there are usually effective measures for treatment and/or prevention.

   • B. anthracis, hantavirus, yellow fever, HIV (cultures).