How many types of Biological Indicators ?

·         AAMI ST34 (Guideline for the use Ethylene oxide and Steam sterilizer biological indicators )

·         ISO 11138 (sterilization health care products - Biological indicators)

·         BS EN 866-3 (Biological system for testing and sterilizers part -3 moist heat sterilizer)

·         Monitor for each load with physical and chemical indicators.

·         Measure the lethality of a sterilization process.

·         Biological Indicators is used bacterial spore suspension.

·         Bacterial spores most of the resistant compare to bacteria.

·         Very difficult kill the spore cell compare to vegetative cell.

·         To check the efficacy of the sterilizing process.

·         Recovery 50-300% (Refer USP 40  general chapter -55 and 1229.5)

·         Types of Biological indicators(BI)

1.       Paper carrier Biological indicators (7 days incubation at 50°-55° C)

2.       Spore suspension Biological indicators.

3.       Self-contained biological indicators( 24-48 hrs incubation at 50°-55°C)

4.       Rapid readout self-contained Biological indicators( 3-4 hrs ).

 1.       Paper carrier Biological indicators or any other Biological Indicator:

·         Indicator includes spores that are added  (a disk or strip of filter paper, glass, plastic or other materials).

•        Mainly used for steam sterilizer, Dry heat  sterilizer validation study.
•        Incubation at as per manufacture recommendation.

       

2   2.  Spore Suspension Biological Indicators :

•      Used for steam sterilizer, Dry heat  sterilizer validation study.
•       Vial having spore suspension.
•        Incubation at as per manufacture recommendation.

     3.  Self-contained biological indicators:

•      Used for steam sterilizer, Dry heat  sterilizer validation study.
•      tube contain Organism disc and media cap having filter paper also.
•      Filter paper avoid the cross-contamination.
•      Media organism growing purpose.
•     Organism Disc having known volume spore count.
•     Less incubation condition(24 to 48 hrs).
•     Self-contained Biological indicator (SCBL) having chemical indicator also. 

    4. Rapid Readout Biological Indicators:

• Less time incubation (3 to 4 hrs).
• Used for steam sterilizer, Dry heat  sterilizer validation study.
•      tube contain Organism disc and media cap having filter paper also.
•      Filter paper avoid the cross-contamination.
•      Media organism growing purpose.
•     Organism Disc having known volume spore count.
  

•   Recommended Spores sterilization Process:

Steam sterilization (121°C)	Geobacillus stearothermophilus (ATCC
	7953)
Steam sterilization (<121°C)	Bacillus subtilis (ATCC 5230)
Dry heat sterilization	Bacillus atrophaeus (ATCC 9372)
Gas sterilization	Bacillus atrophaeus (ATCC 9372)
Ionizing radiations sterilization	Bacillus pumilus (ATCC 27142)
Ultra violet radiation

Name of the Organisum spores	Heat shocking temepature
Geo bacillus sterao thermophilus	95-1000C at 15 minutes
Bacillus subtilis spps	80-850C at 10 minutes
Bacillus pumpilis	80-850C at 10 minutes

Moist heat:  because moist & thermal resistant bacteria’s.

·         Geo bacillus stereo thermopiles

·         Clostridium Sporogenes

·         Bacillus Subtilis

·         Bacillus Coagulants

          Dry heat:

·         Spores of bacillus Subtilis spps.

·         Because the inactivation rate of Endotoxin is slower.

Geo bacillus Stearo thermophilus (7953)

• Steam Sterilization
• Hydrogen Peroxide Sterilization
• Formaldehyde Sterilization
• Propylene Oxide Sterilization
• Ozone Sterilization

 Bacillus Atrophaeus (9372)

• Ethylene Oxide Sterilization
• Dry Heat Sterilization
• Chloroxidene Sterilization
• Ozone

Bacillus Subtilis (6633)

• Low temperature or Steam sterilization

 Bacillus pumpilus (27142)

• Ionizing radiation

• Ultra  Violet Sterilization

Bacillus Cerues

• Food Industry