Copyright © 2009 by Limsoon Wong
1
Life Sciences Institute & Singapore Institute for Clinical Sciences (Brenner Centre)
SAFETY DAY 2009
Overview of
Laboratory Acquired Infections
Contact Info
Scott Patlovich, MPH, CBSPSenior Safety & Health Manager
Office of Safety, Health, & Environment
Office: 6516 [email protected]
Definition of LAI
• Laboratory acquired infection (LAI) = an infection obtained through laboratory or laboratory-related activities as a result of work with infectious biological agents, which may be either symptomatic of asymptomatic
History of LAIs
• Four hallmark studies by Pike and Sulkin collectively identified 4,079 LAIs resulting in 168 deaths between 1930 – 1978
• 159 causative agents identified, although >50% were caused by 10 most common organisms
• Many more LAIs likely unreported during this time period
Source: Pike, 1976 & 1978
(1930-1978)
History of LAIs
• Harding and Byers literature search of LAIs for 20 years following Pike and Sulkin publications found 1,267 overt infections with 22 deaths
• Harding and Byers also reported:– <20% of LAIs from known exposure or documented
accident in the lab– Only 7 documented secondary infections from LAIs
(1979 – 1999)
Despite Controls, LAIs Continue
• 1979 Pike concluded “the knowledge, the techniques, and the equipment to prevent most laboratory infections are available”
• Yet, laboratory acquired infections continue to occur…(even today)
“The conventional wisdom is that laboratory-acquired infections are kept under control by stringent CDC guidelines first introduced in 1984, at a time when investigations of pathogenic bacteria were just starting to bloom. The reality is that no one knows what the reality of laboratory-acquired infections is.”
Biosafety Guidelines & Regulations
• CDC/NIH. Biosafety in Microbiological and Biomedical Laboratories, 5th Edition. (2007) http://www.cdc.gov/OD/ohs/biosfty/bmbl5/bmbl5toc.htm
• World Health Organization. Laboratory Biosafety Manual, 3rd Edition. (2004) http://www.who.int/csr/resources/publications/biosafety/Biosafety7.pdf
• Ministry of Health Singapore. Biological Agents and Toxins Act [BATA]. (2006) http://www.biosafety.moh.gov.sg/bioe/ui/pages/links/abt_bata.htm
Biosafety Controls
• Practices, procedures, and facility controls described in biosafety level criteria (BSLs)
• Risk grouping of infectious biological agents • Emphasis on risk assessment, training, SOPs,
disinfection, waste management, immunization, post-exposure prophylaxis, biosecurity, etc.
• LAIs are not exclusive to BSL-3 or BSL-4 laboratories – many occur in BSL-2 laboratories
Potential Routes of Transmission
• Inhalation – infectious aerosols, droplets
• Ingestion – mouth pipetting; eating, drinking
• Percutaneous inoculation – needlesticks and other contaminated sharps; animal bites; exposure to previously broken or damaged skin
• Mucous membrane exposure – infectious materials in contact with eyes, nose, mouth (splashes, contact from contaminated surfaces)
“Laboratory A” (2002)
Who: 1 unvaccinated worker at private lab (“laboratory A”) processing environmental samples following October 2001 anthrax mailings
Agent: virulent Bacillus anthracis
Route of Exposure: Cutaneous
Source: Positive environmental sample not properly handled, plus individual had pre-existing fresh cut on neck from shaving
Result: cutaneous anthrax disease including black eschar on neck
Other findings: 70% ethanol used for storage vials when 10% bleach prescribed in SOPs; gloves not used to handle vials; wipe samples of lab surfaces indicated only vials were possible source of contamination
“Laboratory A” (2002)
Who: 1 unvaccinated worker at private lab (“laboratory A”) processing environmental samples following October 2001 anthrax mailings
Agent: virulent Bacillus anthracis
Route of Exposure: Cutaneous
Source: Positive environmental sample not properly handled, plus individual had pre-existing fresh cut on neck from shaving
Result: cutaneous anthrax disease including black eschar on neck
Other findings: 70% ethanol used for storage vials when 10% bleach prescribed in SOPs; gloves not used to handle vials; wipe samples of lab surfaces indicated only vials were possible source of contamination
Boston University (2004)Who: 3 researchers suspected with pneumonic tularemia
Agent: Live Vaccine Strain of Francisella tularensis (LVS stock contaminated with wild-type (Type A) virulent form of organism)
Route of Exposure: Inhalation
Source: Undetermined; several procedures occurring during time period (i.e. centrifuging, vortexing, colony counts not in a BSC)
OSHA fine: US$8100 (for improper use of PPE)
Other outcomes: City of Boston Public Health Department to survey lab; first ever City of Boston IBC review panel to review all biomedical research in city; construction of new BSL-4 labs highly controversial with public
Boston University (2004)Who: 3 researchers suspected with pneumonic tularemia
Agent: Live Vaccine Strain of Francisella tularensis (LVS stock contaminated with wild-type (Type A) virulent form of organism)
Route of Exposure: Inhalation
Source: Undetermined; several procedures occurring during time period (i.e. centrifuging, vortexing, colony counts not in a BSC)
OSHA fine: US$8100 (for improper use of PPE)
Other outcomes: City of Boston Public Health Department to survey lab; first ever City of Boston IBC review panel to review all biomedical research in city; construction of new BSL-4 labs highly controversial with public
Science, September 2007
Madison Chamber
Photo courtesy of Hillier Architecture
Texas A&M University (2007)
Who: 1 student worker infected in Brucella lab exposure incident
Agent: virulent Brucella spp.
Route of Exposure: Mucous membrane exposure (eyes)
Source: Improperly trained student worker entered Madison containment chamber to clean unit after aerosolization procedure
CDC fine: US$1 million (plus lost grant dollars during lab shutdown)
Other outcomes: Failure to properly report cases resulted in cease & desist order from CDC on all infectious disease lab work for nearly one year; significant reputational damage to university
Texas A&M University (2007)
Who: 1 student worker infected in Brucella lab exposure incident
Agent: virulent Brucella spp.
Route of Exposure: Mucous membrane exposure (eyes)
Source: Improperly trained student worker entered Madison containment chamber to clean unit after aerosolization procedure
CDC fine: US$1 million (plus lost grant dollars during lab shutdown)
Other outcomes: Failure to properly report cases resulted in cease & desist order from CDC on all infectious disease lab work for nearly one year; significant reputational damage to university
Vaccinia Virus (2007)
Who: 1 unvaccinated worker at a Virginia academic institution
Agent: Vaccinia Virus (live viral component of smallpox vaccine)Route of Exposure: Unknown currentlySource: Recombinant stock likely to be contaminated with “Western
Reserve” strain of virusSecondary Infections: 102 possible contacts identified; no secondary
infections occurred
Vaccinia Virus (2007)
Who: 1 unvaccinated worker at a Virginia academic institution
Agent: Vaccinia Virus (live viral component of smallpox vaccine)Route of Exposure: Unknown currentlySource: Recombinant stock likely to be contaminated with “Western
Reserve” strain of virusSecondary Infections: 102 possible contacts identified; no secondary
infections occurred
Recent Vaccinia LAI’s
Source: US Centers for Disease Control & Prevention
Emory University (1997)
Who: 1 worker at the Yerkes Regional Primate Research Center at Emory University in Atlanta, Georgia engaged in behavioral research on hormonal influences in Rhesus macaques
Agent: Cercopithecine Herpes Virus 1 (B-virus)
Route of Exposure: Mucous membrane exposure (right eye)
Source: Splash of bodily fluid from macaque to unprotected eyes (no safety glasses/goggles worn at time of exposure)
Result: Fatality of 22-year old female (approx. 6 weeks following exposure)
Other findings: No report of exposure until after onset of symptoms of disease; post-exposure treatment not adequate
Note: infected macaques are often asymptomatic (no lesions)
Emory University (1997)
Who: 1 worker at the Yerkes Regional Primate Research Center at Emory University in Atlanta, Georgia engaged in behavioral research on hormonal influences in Rhesus macaques
Agent: Cercopithecine Herpes Virus 1 (B-virus)
Route of Exposure: Mucous membrane exposure (right eye)
Source: Splash of bodily fluid from macaque to unprotected eyes (no safety glasses/goggles worn at time of exposure)
Result: Fatality of 22-year old female (approx. 6 weeks following exposure)
Other findings: No report of exposure until after onset of symptoms of disease; post-exposure treatment not adequate
Note: infected macaques are often asymptomatic (no lesions)
Other Infectious Disease Lab “Mishaps”
Texas Tech UniversityWho: Thomas Butler
Agent: Yersinia pestis
What: Apparent loss of 30 vials containing bacteria
How Much: 69 counts including illegal transportation, tax fraud, embezzlement, fraud, lying to federal officials
Outcomes: 2 years jail time & US$38,000 fine
LAIs – Lessons Learned
• Prevention of LAIs can be achieved through:– Risk assessment! Risk assessment! Risk assessment! – Establishment of SOPs (controls) appropriate for
infectious organisms used– Immunization, when available– Education and training – Use of appropriate precautions including engineering,
administrative, and PPE controls– Understanding of disease signs & symptoms– Prompt injury/accident/illness reporting
Thank You!