Biosafety in the TB Laboratory

Presented by Peggy Coulter

with(Patient Safety Monitoring in International Laboratories)

Prepared for the ACTG Conference24 June 2009

Purpose of TrainingGCLP Standards:

DAIDS supported clinical trials and studies involving human subjects must ensure

compliance with federal regulations including procedures to protect the safety of all

participants.Safety of laboratory employees must be a top

priority for all lab facilities.

Abbreviations

• BMBL- Biosafety in Microbiological and Biomedical Laboratories (CDC)

• LBM- Laboratory Biosafety Manual (WHO)• BSC- Biosafety Cabinet• LAI- Laboratory Associated Infection• TB- for Mycobacteriology testing

Objectives: At the end of this training you will be able to:

• Locate resources for biosafety guidelines;• Describe the elements of biosafety;• Identify standard and special practices in

biosafety;• Select and use appropriate biosafety control

measures;• Conduct an internal risk assessment and self

inspection of the laboratory.

Training Topics• Principles of Biosafety• Standard Microbiological Practices• Special Practices• Personal Protective Equipment• Containment Equipment• Laboratory Facilities• Safety Practices• Risk Assessment and Self Inspection

Resources for Principles of Biosafety

• Biosafety in Microbiological and Biomedical Laboratories (BMBL) from CDC at http://www.cdc.gov/OD/ohs/biosfty/bmbl5/BMBL_5th_Edition.pdf

• Laboratory Biosafety Manual from W.H.O. at http://www.who.int/csr/resources/publications/biosafety/Biosafety7.pdf

Introduction to BiosafetyAll laboratory facilities must follow “Standard or Basic Precautions”.

Biosafety guidelines evolved from the microbiological and biomedical community to reduce laboratory

associated infections (LIA’s) and to protect the public health and environment.

Principles of Biosafety

Two basic elements:

• Containment• Risk Assessment

Routes of transmission for LAI’s

• Direct skin, eye, or mucosal membrane;• Parenteral inoculation by a contaminated

sharp or needle;• Ingestion of liquid suspension;• Inhalation of infective aerosols.

Risk Assessment

• Pathogenicity of the microorganism• Prevalence of tuberculosis and rate of MDR• Types of testing performed or referred• Volume of tests• Personnel expertise and attitude• Facilities and equipment

WHO Risk

Group Risk Microorganism

1No or low individual

and community risk.

A microorganism that is unlikely to cause human or animal disease.

2Moderate individual risk, low community

risk.

A pathogen that can cause human or animal disease but is unlikely to be a serious hazard to laboratory workers, the

community, livestock or the environment. Laboratory exposures may cause serious infection but effective

treatment and preventative measures are available and the risk of spread of infection is limited.

3 High individual risk, low community risk.

A pathogen that usually causes serious human or animal disease but does not ordinarily spread from one infected

individual to another. Effective treatment and preventative measures are available.

4 High individual and community risk.

A pathogen that usually causes serious human or animal disease and that can be readily transmitted from one individual to another, directly or indirectly. Effective

treatment and preventative measures are not usually available.

Levels of Biosafety, and Testing Levels

Testing Level

Biosafety Level(BSL) Activity

One 2•Collect clinical specimens•Transport specimens to a higher level testing laboratory•May prepare and examine smears of killed tubercle bacilli

Two 3

•Level One activities •Process specimens for microscopy and culture•Identify M. tuberculosis•Perform DST on M. tuberculosis

Three 3

•Level One and Two activities•Identify all Mycobacterium species from clinical specimens•Perform DST against all mycobacteria•Conduct research and provide training to other laboratories

Basic Microbiology Practices

• Policies and access • Safety practices

• Decontamination and Waste• Training

Specimens

Photo of washroom

Handling of Specimens

• Collection• Transportation• Receipt of incoming

specimens• Opening packages

Special Practicesenhance worker safety, provide

environmental protection and address the risk of handling agents

requiring increasing levels of containment.

Reminder: BSL-3 practices should be used whenever M.tuberculosis is handled even if the physical

facilities are a BSL-2.

All persons entering the laboratory must be advised of the potential hazards and meet specific entry/exit requirements.

Animals and plants not associated with the work being performed must not be permitted in the laboratory.

Laboratory personnel must be provided medical surveillance and offered appropriate immunizations for agents handled or potentially

present in the laboratory.

A laboratory-specific biosafety manual must be prepared, adopted as policy and made available and accessible to

the laboratory staff.

This is a written plan thatdefines safe lab practices, spill and emergency

procedures

The laboratory supervisor must ensure that the laboratory personnel

demonstrate proficiency in standard and special microbiological practices

before working in the mycobacteriology lab.

Personal Protective Equipment (PPE)

• Gowns, lab coats• Gloves

• Respirators, masks, goggles, glasses

• Shoe cover, boots

Lab coats vs. Gowns

Gloves

Approved TypeCorrect Size

DonningProper Use

Removal

Shoes and Covers

Open-toed footwear is not appropriate in the laboratory.

Respirator program implemented by the laboratory's safety officer or person designated to perform

this task and should include written procedures concerning how to:

a)select the appropriate respirator, b)conduct fit-testing, and

c)train personnel on the use, fit checking, and storage of the respirator.

Correct Type and Fit of Respirators

Dust and Paint FumesDust

N-95

Surgical Mask

PAPR

Safety Equipment

• Needle locking syringes• Centrifuge safety carriers• Microburners• Biosafety Cabinets (BSC)

Centrifuge Safety

Biosafety Cabinets (BSC)All procedures involving the manipulation

of infectious materials must be conducted within a BSC, or other physical containment devices. No work with open vessels is conducted on the bench. When a procedure cannot be performed within a BSC, a combination of personal protective devices, such as centrifuge safety cup with sealed rotor, must be used.

Use of BSCA BSC is the most important piece of

containment equipment but only

• if properly installed, • appropriate air velocity is maintained during

use, • proper procedures are used.

Use of biological safety cabinets

Facilities

–Ventilation–Temperature control–Sinks, eyewash, trashcans–Furniture and decontamination

Plan of a culture laboratory

Handling of contaminated laboratory supplies

• Glassware• Sputum containers• Applicator sticks, paper, pipettes• Positive and negative slides

Waste HandlingPotentially infectious materials must

be placed in a durable, leak proof container during collection, handling,

processing, storage, or transport within a facility.

No infected material should leave the laboratory except when it is properly packed for

transport to another laboratory.

Cleaning laboratory materials

Disinfection and Sterilization

A basic knowledge of disinfection and sterilization is crucial for biosafety in

the laboratory.

Laboratory equipment should be routinely decontaminated, as well as, after spills,

splashes, or other potential contamination.

Autoclaves

Boiling and burning

Safety Practices

• Pipetting• Microscopy

• Handwashing

Handwashing

Training

Initial on hireAnnual updates

Staff should be observed in their biosafety practices

Laboratory safety does not just happen.

The best defense against a laboratory accident is a well-thought-out plan to neutralize its

effects as quickly and effectively as possible.

• recognize that accidents can and will occur• formulate a plan of action• discuss ways to minimize and prevent

accidents

Spill ProceduresLaboratory accidents in the TB

laboratory result in possible formation of aerosols.

Spills involving infectious materials must be contained, decontaminated, and cleaned up by staff properly trained

and equipped to work with infectious material.

Emergency Procedures

• Puncture wounds, cuts and abrasions• Ingestion of potentially infectious material• Potentially infectious aerosol release (outside a

biological safety cabinet)• Broken containers and spilled infectious substances• Breakage of tubes containing potentially infectious

material in centrifuges not having sealable buckets• Breakage of tubes inside sealable buckets (safety

cups)

Incidents that may result in exposure to infectious materials must be immediately

evaluated and treated according to procedures described in the laboratory

biosafety manual. All such incidents must be reported to the laboratory supervisor. Medical evaluation, surveillance, and

treatment should be provided and appropriate records maintained.

Support Staff

The safe and optimum operation of a laboratory is dependent to a great extent

on the support staff, it is essential that such personnel are given

appropriate safety training.

THE MYCOBACTERIOLOGY LABORATORY IN NEED OF IMPROVEMENT

Physical facilities BSL-2 vs BSL-3

Laboratory Inspection

• Engineering controls• Administrative controls• Personal protective equipment• General Laboratory Safety

Risk Assessment

Will evaluate all procedures for risks related to aerosol generation and injury from

contaminated sharp objects (e.g., needle sticks) and develop a strategy for safe, step-by-

step manipulation of both specimens and cultures.

Why an assessment?Who should perform it?

When should it be done?What tools are used?

How should it be done?

Potential Hazards:

The following slides show some improper biosafety practices or containment safeguards

found in some TB laboratories.

Summary

Although the incidence of tuberculosis is higher in laboratory workers than for the general

population, the risk of becoming infected with M. tuberculosis in the laboratory can be

minimized through the use of the engineering controls, administrative procedures, and

specific work-place practices that are presented in these guidelines.

Questions?

Resources

• www.psmile.org• www.asm.org• www.clsi.org• www.cdc.gov• www.who.int./csr/resources/publications/biosafety/en/Biosafety7.pdf