1. Immunization of Health Care Workers: more than just the flu Mary Vearncombe, MD, FRCPC Medical Microbiologist, Hospital Epidemiologist Sunnybrook and Women’s College Health Sciences Centre phone: (416) 480-4243 FAX: (416) 480-6845 e-mail: mary.vearncombe@swchsc.on.ca

2. HCW Immunization: Background HCWs are at risk of exposure to and possible transmission of communicable diseases - some vaccine preventable establishing and maintaining immunity is an essential component of Occupational Health and Infection Prevention and Control programs applies to all health care facilities –offices, clinics, acute care, LTC, labs, first responders applies to all health care personnel –employees, physicians, students, contract workers, volunteers

3. HCW Immunization: Background immunization protects HCWs, their families, colleagues and patients cost containment through prevention of infection furloughing susceptibles after exposure costs of prophylaxis costs of treatment absenteeism during acute illness disability following illness outbreak investigation and control

4. Disease Categories for HCW Immunization active immunization strongly recommended - specific risk for HCWs –i.e., hepatitis B, influenza, measles, mumps, rubella, varicella active ± passive immunization may be indicated in certain circumstances –e.g., hepatitis A, meningococcal disease, TB, pertussis immunization recommended for all adults –i.e., tetanus, diphtheria

5. Occupational Health Assessment 1.before placement (after employment) health inventory: –immunization status –history: predisposing conditions for acquisition/transmission of infection –to guide: further immunizations, post-exposure management –opportunity for adult immunization in immigrant HCWs education: –importance of maintaining personal health –need for annual influenza vaccine

6. Personnel Immunization prevent transmission prevent work restrictions after exposure cost-effective compared to: –treatment of cases –outbreak control mandatory vs voluntary programs screening programs: HBV, MMR, varicella –documentation of vaccine receipt or immune serology document refusal

7. Hepatitis B Vaccine: Pre-Exposure Pre-placement: HB vaccine for all HCWs at risk of exposure to hepatitis B, i.e., who may have contact with blood, body fluids or sharps risk often highest during training period –vaccination should be completed during training, before clinical exposure test for anti-HBs 1 month after vaccine series complete complete 2nd 3 dose series for primary series non- responders, then re-test for anti-HBs if anti-HBs positive, consider immune if non-immune, counsel regarding exposure

8. Hepatitis B Vaccine: Pre-Exposure Ongoing Surveillance: periodic antibody testing not recommended booster doses not recommended HBV unimmunized or non-responders to vaccine at risk for exposure should be offered annual screening

9. Hepatitis B Vaccine: Post-Exposure HBV contact: response dependent on the vaccination and antibody status of the HCW known anti-HBs positive: no further action required non-responder: HBIG + repeat in 1 month unvaccinated: HBIG + initiate vaccine give HBIG ASAP and within 48 hours of exposure risk for non-immune contact up to 30%

10. Influenza Vaccine: NACI Recommended Recipients “People capable of transmitting influenza to those at high risk for influenza- related complications” –health care workers: acute care, long term care, home care and outpatient settings

11. Influenza Vaccine: Why should I be immunized? You will protect yourself from acquiring “the flu”, or if you do get “the flu” it will be less severe. Influenza vaccine is effective in otherwise healthy adults. –NEJM 333:14 889-893, 1995 –JAMA 281:10 908-913, 1999 –JAMA 284:13 1655-1663, 2000

12. Influenza Vaccine: Why should I be immunized? You will protect your patients from influenza. Vaccination of HCWs reduces illness and mortality of frail elderly patients more effectively than vaccination of patients. –JID 175:1-6, 1997 –Lancet 355:8/1/ 2000, 93-97

13. Influenza Vaccine Pre-placement: counsel with regard to implications of transmission of respiratory viruses (esp influenza) to high risk patients counsel with regard to expectation of annual influenza immunization Ongoing Surveillance: recommend influenza vaccine annually to all HCWs before the beginning of the influenza season utilize strategies to maximize vaccine coverage –e.g., mobile carts, shift coverage, education, incentives

14. Influenza Vaccine Influenza outbreaks: immunized personnel may continue to work unimmunized personnel working in the affected unit must take antiviral chemoprophylaxis for 2 weeks if they also receive vaccine or until end of outbreak unimmunized personnel who refuse chemoprophylaxis should not provide patient care

15. Measles Vaccine Pre-placement immunization: acceptable evidence of immunity: –positive serology –documented receipt of vaccine (single vs double dose (NACI) ) –physician documented clinical measles –born before 1970 offer vaccine to all non-immune HCWs (MMR) immunity should be condition of employment –HCW responsibility to avoid causing harm

16. Measles Vaccine Post-Exposure: airborne transmission, highly contagious (masks may not provide protection) only immune HCWs should be assigned to patients with measles immune HCW: no restriction non-immune HCW: exclude from work day 5 to day 21 immunization of susceptible persons within 72 hours of exposure usually prevents measles

17. Rubella Vaccine Pre-placement immunization: acceptable evidence of immunity: –positive serology –documented receipt of vaccine offer vaccine to all non-immune HCWs (MMR) –goal: prevention of CRS –females and males immunity should be condition of employment –HCW responsibility to avoid causing harm vaccine contraindicated during pregnancy

18. Rubella Vaccine Post-Exposure: direct face-to-face contact (even if mask worn) only immune HCWs should be assigned to patients with rubella immune HCW: no work restriction non-immune HCW: exclude from work day 7 - 21

19. Mumps Vaccine Pre-placement immunization: acceptable evidence of immunity: –positive serology –documented receipt of vaccine –physician documented clinical mumps –born before 1970 offer vaccine to all non-immune HCWs (MMR)

20. Mumps Vaccine Post-Exposure: droplet transmission, saliva only immune HCWs should be assigned to patients with mumps immune HCW: no restriction non-immune HCW: exclude from work day 12 - 26 mumps immunization after exposure may not prevent disease, but will confer protection against future exposures

21. Varicella Vaccine Pre-placement: ascertain history of varicella /zoster –definite history: assume immune –negative or uncertain: antibody screen offer vaccine to HCWs who are non-immune –post-vaccine serology not recommended: high efficacy of vaccine commercially available tests not sufficiently sensitive assign only immune HCWs to patients with varicella / zoster

22. Varicella Vaccine Adverse Events: Post-vaccine rash: –at injection site: cover and may continue to work –non-injection site: small number of papules/ vesicles and low grade fever - should not work with high-risk patients varicelliform rashes within 2 weeks of vaccine are usually due to wild-type virus

23. Varicella Vaccine Post-Exposure: airborne transmission for varicella or disseminated zoster, or direct contact with lesions –masks may not be effective in preventing transmission report exposure to OHS –immune status unknown: test for antibody –immune: may continue to work –non-immune: exclude from work from 10th day after the first exposure to the 21st day after the last exposure –pregnant and non-immune: offer VZIG, exclude until 28th day after last exposure

24. Varicella Vaccine Post-Exposure: management of vaccine recipients ??? vaccine offers 70 - 90% protection against varicella; 95% protection against severe varicella consider: –test for immunity; if negative, repeat in 5-6 days (serology insensitive - natural exposure may boost to detectable level), and/or –observe daily at start of shift for signs/ symptoms of varicella

25. Varicella Vaccine Post-exposure vaccine use: vaccine may prevent or reduce severity of varicella if given within 3 days (possibly up to 5 days) after exposure furlough still required immunity for subsequent exposures outbreak control

26. Meningococcal Disease: Occupational Risk in Clinical HCWs There is no risk to HCWs from casual contact with patients with meningococcal disease Transmission to HCWs from patients with invasive meningococcal disease may occur after intensive, direct contact where the patient’s respiratory secretions contaminate the HCW’s oral/nasal mucous membranes

27. Meningococcal Disease: Occupational Risk in Clinical HCWs retrospective survey 1982-1996: doctor, nurse, ambulance worker - prolonged contact, airway management Lancet 356:1654-1655, Nov 11, 2000 pediatrician performed endotracheal intubation ICHE 20:564, Aug 1999 4 medical staff after mouth-to-mouth resuscitation JAMA 220:1107-1112, 1972 ER nurse assisted in intubation, suctioning CDC, MMWR 27:358-363, 1978 all no barriers (i.e., mask), no prophylaxis

28. Meningococcal Disease: Occupational Risk in Laboratory Technologists 2 technologists MMWR 40:46-47, 1991 1 technologist CCDR 20:12-14, 1994 (Quebec) Biosafety Advisory, Health Canada, Jan, 1992 3 technologists HIC 28:45-60, April 2001 –33 cases retrospectively since 1965 2 technologists MMWR 51:141-144, 2002 –electronic request: 14 cases worldwide in 15 years

29. Meningococcal Disease: Occupational Risk in Laboratory Technologists no identified breaches in laboratory technique many cases fatal at least one case from a non-invasive isolate rate of disease in lab workers dealing with N. meningitidis cultures elevated (US, UK)

30. Meningococcal Vaccine: NACI Laboratory and Healthcare Workers routine vaccination of healthcare workers not currently recommended –antibiotic chemoprophylaxis sufficient in high risk situation research, industrial and clinical laboratory personnel who are routinely exposed to N. meningitidis cultures: –MenACYW-Ps recommended –consider MenC-conjugate in addition –vaccine does not replace lab safety standards

31. Hepatitis A Vaccine Pre-placement: routine use of vaccine not recommended –HCWs not at increased risk –routine infection control practices prevent transmission counsel re prevention of transmission, i.e., hand hygiene; no eating, drinking, in patient care areas Post-Exposure/Outbreak Control: give vaccine for post-exposure prophylaxis as soon as possible and within 7 days of exposure (not required for routine care of patients with hepatitis A)

32. Pertussis Vaccine pertussis is a frequent cause of cough illness in adolescents and adults; major reservoir of disease and source of transmission nosocomial transmission to both patients and HCWs occurs prevention of secondary cases difficult as symptoms are non-specific and diagnosis difficult during catarrhal stage role of acellular pertussis vaccine in previously immunized HCWs needs evaluation

33. BCG Vaccine BCG vaccine does not provide permanent or absolute protection against TB loss of tuberculin skin test marker of infection BCG vaccination of HCWs, including MLTs, may be considered when all of the following exist: –there is a considerable risk of exposure/ transmission of tubercle bacilli –a high percentage of strains are drug-resistant –infection control measures have been ineffective or are not feasible

34. Tetanus / Diphtheria Vaccine Pre-placement: immunization history maintain immunity with booster Td (tetanus/diphtheria toxoid) every 10 years

35. Polio Vaccine Pre-placement: immunization history HCWs who may have close contact with patients who may be excreting wild or vaccine poliovirus and laboratory workers handling specimens that may contain polioviruses should be immunized if previously unvaccinated; use inactivated polio vaccine

36. ROUTINE IMMUNIZING AGENTS STRONGLY RECOMMENDED FOR HEALTH CARE PROVIDERS Hepatitis B vaccine Influenza vaccine Measles/Mumps/Rubella vaccine (MMR) Varicella vaccine Tetanus/Diphtheria vaccine (Td) ± Polio vaccine DISEASES FOR WHICH POSTEXPOSURE PROPHYLAXIS MAY BE INDICATED: DiphtheriaRabies Hepatitis AScabies Hepatitis BVaricella/Zoster Meningococcal diseaseHIV PertussisInfluenza (outbreaks)

37. Essential References 1.Chin, Control of Communicable Diseases Manual, 17 th edition, 2000, American Public Health Association 2.Canadian Immunization Guide, 6 th edition, 2002, NACI Recommendations, Health Canada 3.Guide for Infection Control in Healthcare Personnel, 1998, Centers for Disease Control and Prevention, Public Health Service, US Department of Health and Human Services 4.Prevention and Control of Occupational Infections in Health Care, Health Canada, 2002 5.Immunization of Health-Care Workers, 1997 Recommendations of ACIP and HICPAC, Centers for Disease Control and Prevention, Public Health Service, US Department of Health and Human Services