Agent Specific Occupational Health & Safety Training

1. Agent Specific Occupational Health & Safety Training Thomas H. Winters, MD, FACOEM Medical Director Occupational & Environmental Health Network Waltham, MA

2. Objectives • Describe categories and types of agents and their exposure risks • List available vaccines • Identify appropriate steps for exposure including reporting, treatment and follow-up

3. Risk Assessment • BLS 1, 2, 3 or 4 • Types of exposures • Bacterial • Viral • Toxins • Chemical • Rickettsial, protozoal, helminth, fungus • Risk of disease usually same as exposure risk • Inhalation, mucosal contact, or nonintact skin contact • Amount of dose • Vaccination and antibody titers • Virulence of the organism • Associated illness or medications • Prophylactic antibiotics Reference: Rusnack et al, 2004, p. 791

4. Gap Analysis • Review of policies • Review of procedures • Assessment of current training program • Evaluation of current protective measures • Assessment of expert resources

5. Levels of Protection • OSHA • Engineering controls • Work practice controls • Administrative controls • PPE

6. Pre-Placement Evaluations • Obtain accurate job description • Speak with direct supervisor if require clarification • History • General health history • Obtain immunization records • Previous occupational exposures • Physical • Focus • Cardiac • Respiratory • Immunologic • Skin • Baseline lab work-exposure dependent • CBC, LFT, Chem-20 • Titers • Serum storageLaboratory personnel • Immunizations/monitoring (i.e. Hepatitis B vaccine, baseline serum samples, TB skin testing) • Immuno-compromised person evaluation/policy • Other exposure dependent testing • Chest x-ray • EKG • PFTs

7. Pre-Placement Evaluations • Baseline lab work-exposure dependent • CBC, LFT, Chem-20 • Titers • Serum storage laboratory personnel • Immunizations/monitoring (i.e. Hepatitis B vaccine, baseline serum samples, TB skin testing) • Immuno-compromised person evaluation/policy • Other exposure dependent testing • Chest x-ray • EKG • PFTs

8. Annual Medical Surveillance • Questionnaire • Answers may trigger physical and additional testing • History • Change in job status or exposure type • Physical • Laboratory testing • Exposure specific

9. Common Agents • AGENTS CAUSE HUMAN DISEASE WITH SERIOUS OR LETHAL CONSEQUENCES; INDIGENOUS OR EXOTIC • Human cell lines • Shigella • Borrelia burgdorferi • Erlichia (HGE) • Babesia microti (human babesiosis) • Plasmodium spp (rodent) • Plasmodium spp (mosquito born) • Mycobacterium Tuberculosis • Vaccinia • Adenovirus • Herpes Simplex virus • E Coli • Francisella tularensis • Hepatitis B, C • Poliovirus • HIV

10. Vaccinations • Exposure specific • Many vaccines are investigational

11. FDA approved Anthrax Yellow fever Smallpox Plaque Not FDA approved Tulermia Q Fever EEE Pentavalent Botulism toxoid Vaccines Ref: Rusnack et al, 2004, p. 793

12. Allergies • Latex • Lab animals • Irritant contact dermatitis • Frequently related to PPE

13. Occupational Asthma • Animal handlers • Allergies • Pre-existing • RAST • RAST for other allergens: rabbit, non-human primates, gerbils • Prick test • Mouse urine antigen, mouse epithelium, bedding • Occupationally acquired

14. Post-Exposure Prophylaxis • Bacterial agents • Salmonella, Shigella • Anthrax • Plaque • Tularemia • Viral agents • HIV, Hep B, Hep C • Influenza • Vaccinia • Toxins • Few of options • ClL. Botulinum-trivalent equine anti-toxin

15. Employee Training • Education • Critical to minimize exposure risk • Increase understanding to improve rapid reporting to optimize outcomes • Employee awareness regarding resources • 24/7 expert medical coverage • MD, NP

16. Respiratory Protection Program • Fit testing • Education • Periodic spirometry • Annual questionnaire • May trigger physical examination • Compliance

17. PPE • Eye wear, face shields • Protective clothing • Gloves • Nitrile • Chemical

18. Final Evaluations • Written report • Pre-placement • Fit for duty • Fit for duty with restrictions • Not fit for duty • Medical hold

19. Assessment of Factors Influencing the Disease Risk After Exposure to an Agent • The risk of disease is usually the same as exposure risk or lower if individuals had prior vaccination, exposure to nonpathogenic strain, or given antibiotic prophylaxis. • Was there inhalation, mucosal contact, or non-intact skin contact with agent? Was there immediate cleansing with disinfectant (time interval from incident to cleansing)? Immediate cleansing of agent may reduce disease risk. • What was the estimated dose of exposure? What is the estimated infective dose/lethal dose of the agent? • Was the individual vaccinated against the agent? Do they have protective antibody titers? How effective is the vaccine? Prior vaccination may lower the risk of disease. • What is the virulence of the organism? Exposure to non-virulent strains may lower disease risk (i.e. non-virulent Steme strain of B.anthracis). • Does individual have an illness or take medications that predispose for higher risk for disease? • Are prophylactic antibiotics available against the organism? Post-exposure antibiotic prophylaxis may lower disease risk. Consider investigational antiviral agents in individuals with moderate to high-risk viral exposures who are not vaccinated to lower the risk of disease. Ref: Rusnak et al., 2006; Heymann, 2004, Winters, 2006

20. Post-Exposure Evaluation • Employee interview • Categorize exposure • Medical history • Physical exam

21. Case Study • 25 yr old female graduate student at a major university presents to University Health Services with a two day history of fever to 103, abdominal pain, bloody/watery diarrhea, shaking chills, nausea, vomiting, anorexia and abdominal pain. She has taken loperamide for the diarrhea and tenesmus which she believes has made her symptoms worse.

22. Clinical Investigation • Past medical history • Recent travel • Occupation • Student • Research activities/exposures

23. Differential Diagnosis • Influenza • E coli • Shigellosis • Salmonella • Campylobacter jejuni • Schistosoma • Entamoeba histolytica • Ulcerative colitis

24. Diagnosis • Shigellosis • Four types of Shigella: • S. dysenteriae, S. flexneri, S. boydii, and S. sonnei. • Shigella dysenteriae 1 (Shiga toxin) • Rare in the U.S. – this finding likely lab related with no travel history • Incubation: 1-4 days Duration: 5-7 days • Complications may include: • Toxic megacolon • Intestinal perforation • Hemolytic uremic syndrome (HUS) • Case fatality rate as high as 20% among hospitalized cases (Heymann, 2004,p. 487) • 8% of patients with HUS develop lifelong complications such as HTN, seizures, blindness or paralysis Ref: http://www.niaid.nih.gov/factsheets/shigellosis.htm

25. Diagnostic Testing • Microscopy of fresh stool (time sensitive- within 2 hours) • Stool culture and serotyping • Enzyme immunoassay for Stx for S dysenteriae type 1 Ref: http://www.emedicine.com/ped/topic2085.htm

26. Treatment • Most cases resolve within 5-7 days • Hospitalized • Supportive therapy • Intravenous fluids • Antipyretics • Anti-diarrheals not typically used- may make prolong/worsen course illness • Increasing resistance to TMP-SMZ and ampicillin • Ciprofloxacin 500mg po x 5 days, or Z-pack • Monitor for complications (HUS)

27. Prevention • Lab safety re-education • Hand washing • Policy/procedure review • Rapid reporting of breech in lab proctols

28. References • Cohen, J. and Powderly, W. ( 2004) Infectious diseases, 2nd ed. St. Louis: Mosby. • Heymann, D. L. ed. (2004). Control of communicable diseases manual, 18th ed. Washington, DC: American Public Health Association. • National Research Council. (1997). Occupational health and safety in the care and use of research animals. Washington, DC: National Academy Press • Rusnak, J. M. et al. (2004, August). Management guidelines for laboratory exposures to agents of bioterrorism. JOEM, 46 (8), 791-800. • U.S. Department of Health and Human Services. (1999). Biosafety in microbiological and biomedical laboratories, 4th ed. Washington, DC: U.S. Government Printing Office. • http://www.cdc.gov/od/ohs/pdffiles/4th%20BMBL.pdf