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Sterilization and disinfection

and biosafety

§1 §1 Sterilization and Sterilization and disinfectiondisinfection

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§2 Biosafety

1. What is biosafety?

The biosafety is responsible for the development

and oversight of programs to ensure the safe handling,

use, transport, and disposal of biological materials.

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Biosafety in Various DisciplinesBiosafety in Various Disciplines

ECOLOGY: referring to imported life forms not indigenous to ECOLOGY: referring to imported life forms not indigenous to the region (Reggie the alligator)the region (Reggie the alligator)AGRICULTURE: reducing the risk of alien viral or transgenic AGRICULTURE: reducing the risk of alien viral or transgenic genes, or prions such as BSE/"MadCow“; reducing the risk of genes, or prions such as BSE/"MadCow“; reducing the risk of food bacterial contaminationfood bacterial contaminationCHEMISTRY: nitrates in water, PCB levels affecting fertility, CHEMISTRY: nitrates in water, PCB levels affecting fertility, and so on.and so on.EXOBIOLOGY: i.e., NASA's policy for containing alien EXOBIOLOGY: i.e., NASA's policy for containing alien microbes that may exist on space samples - sometimes called "microbes that may exist on space samples - sometimes called "biosafety level 5“ 5“MEDICINE: MEDICINE: referring to organs or tissues from biological referring to organs or tissues from biological origin, or genetic therapy products, virus; pathogenic bacteria, origin, or genetic therapy products, virus; pathogenic bacteria, etc. etc. levels of lab containment protocols BSL-1, 2, 3, 4 in rising order of danger

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※ ※ Charles Baldwin at National Charles Baldwin at National

Cancer Institute at NIH.Cancer Institute at NIH.

※ ※ Blaze orange – most visible under Blaze orange – most visible under

harsh conditionsharsh conditions

※ ※ Symbol to be “memorable but Symbol to be “memorable but

meaningless” so it could be meaningless” so it could be

learned.learned.

2. Biohazard Symbol2. Biohazard Symbol

△ △ Mandatory Warning SignMandatory Warning Sign

△ △ Designate Biosafety LevelDesignate Biosafety Level

△ △ Contact InformationContact Information

△ △ Special Entry ProceduresSpecial Entry Procedures

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Biosafety activities include:

1.registration, review, monitoring, and training for research involving

infectious agents and recombinant DNA molecules.

2.Consultation and training regarding occupational exposure to

bloodborne pathogens

3.Distribution, collection and destruction of sharps disposal containers.

4.Treatment and incineration of pathological waste.

5.Selection, proper use and maintenance of biosafety cabinets.

6.Emergency response to incidents involving biological materials.

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3. Classification of infective microorganisms by risk group

Risk Group 1 AgentsRisk Group 1 Agents

※ ※ No or low individual and community riskNo or low individual and community risk

※ ※ A microorganism unlikely to cause human or A microorganism unlikely to cause human or

animal diseaseanimal disease

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Risk Group 2 AgentsRisk Group 2 Agents

※ ※ Moderate individual risk, low community riskModerate individual risk, low community risk

※ ※ Pathogen causes human or animal disease but is unlikely to Pathogen causes human or animal disease but is unlikely to

be a serious hazard to laboratory workers, the community, be a serious hazard to laboratory workers, the community,

livestock or the environmentlivestock or the environment

※ ※ May cause serious infection but effective treatments and May cause serious infection but effective treatments and

preventive measures are availablepreventive measures are available

※ ※ Risk of spread is limitedRisk of spread is limited

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Risk Group 3 AgentsRisk Group 3 Agents

※ ※ High individual risk, low community riskHigh individual risk, low community risk

※ ※ Pathogen usually causes serious human or animal disease Pathogen usually causes serious human or animal disease

but does not ordinarily spread to others but does not ordinarily spread to others

※ ※ Effective treatment and preventive measures are Effective treatment and preventive measures are

availableavailableRisk Group 4 AgentsRisk Group 4 Agents

※ ※ High individual and community riskHigh individual and community risk

※ ※ A pathogen causes serious human or animal disease; A pathogen causes serious human or animal disease;

readily transmitted from one individual to anotherreadily transmitted from one individual to another

※ ※ Effective treatment and preventive measures are usually Effective treatment and preventive measures are usually

not availablenot available

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BSL-2 BSL-3BSL-1

Lower Risk Higher Risk

BSL-4

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Risk Group

Biosafety Level Laboratory Type Laboratory Practices

Safety Equipment

1Basic – Biosafety Level 1

Basic teaching, research

GMT None; open bench work

2

Basic – Biosafety Level 2

Primary health services; diagnostic services, research

GMT plus protective clothing, biohazards sign

Open bench plus BSC for aerosols

Risk Groups and Biosafety LevelsRisk Groups and Biosafety Levels

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Risk Group

Biosafety Level Laboratory Type Laboratory Practices

Safety Equipment

3

Containment- Biosafety Level 3

Special diagnostic services, research

Level 2 + special clothing, access control, directed airflow

BSC and/or other primary devices for all activities

4

Maximum Containment – Biosafety Level 4

Dangerous pathogen units

Level 3 + airlock entry, shower exit, special waste disposal

Class III BSC, or positive pressure suites with class II BSCs, double ended autoclave

Risk Groups and Biosafety LevelsRisk Groups and Biosafety Levels

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4. Personal Protection

4.1 protect the patient

▲ First Rule: single use equipment

▲ Disinfect

▲ Work in a clean, dedicated area

4.2 protect yourself

※ Use personal protective equipment

— disposable gloves

— laboratory coats / gown

— mask

— protective eyewear / face shields if procedure is likely

to generate aerosols

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4.3 protect others, protect the environment

△ Package samples appropriately for transport

△ Decontaminate spills - 10% bleach

△ Disinfect working areas – 1% household bleach

△ Soak contaminated non-disposable equipment / material –

1% household bleach for 5 minutes

△ Place waste in leak-proof bags

△ Ensure safe final management of waste

△ Protect cleaning personnel – coat, gloves

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4.4 Dispose sharp material in biohazard sharps containers

△ If no sharps container: improvise one and collect sharps

immediately to prevent needle-stick injury

△ Have first aid kit readily accessible

△ Do not reuse contaminated equipment

sharps containers

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5. Bioterrorism and precaution

The bioterrorism is one kind

of activity using microorganisms

such as bacteria, fungi or virus with

strong pathogenicity to attack the

human, which brings severe damage

to the social public and the

environment

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5.1 Bioterrorism threat graduation

Category A Agents

Agents that can:

– Easily disseminated or transmitted from person to person

– Causes high mortality & potential for major public health

impact

– Could cause panic and social disruption

– Requires special action for public health preparedness

The biggest harm

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Class A Agents

— Variola major (Smallpox)

— Bacillus anthracis (Anthrax)

— Yersina pestis (Plaque)

— Clostridium botulinum toxin (Botulism)

— Francisella tularensis (Tularemia)

— Filoviridae

△ Ebola (Ebola hemorrhagic fever)

△ Marburg (Marburg hemorrhagic fever)

— Arenaviruses

△ Lassa (Lassa fever)

△ Junin (Argentine hemorrhagic fever)

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Category B Agents

Agents that can:

– Moderately easy to disseminate

– Causes moderate morbidity & low mortality

– Requires special enhancements of CDC’s diagnostic

capacity and disease surveillance

Medium harm

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Class B Agents

— Coxiella burnetii (Q Fever)

— Brucella spp. (Brucellosis)

— Burkholderia mallei (Glanders)

— Alphaviruses

△ Venezuelan encephalomyelitis

△ Eastern & Western encephalomyelitis

— Epsilon toxin from Clostridium perfringes

— Staphylococcus enterotoxin B

Class C Agents

The lowest harm

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5.2 The disseminated way of biowarfare agent

※ tiny particles

※ medium insects, such as the mosquito, fly, cockroach, louse,

flea and rodents carried pathogens

5.3 The precaution measures to biowarfare agents

To research the related pathogen and develop effective

vaccine and medicine are major mothods.

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SummaryDefinition:SterilizationDisinfectionAntisepsisBacteriostasisAsepsisBiosafety