Kathleen Harriman, PhD, MPH, RNVaccine Preventable Disease Epidemiology SectionCalifornia Department of Public HealthImmunization Branchkathleen.harriman@cdph.ca.gov

Healthcare PersonnelImmunization

Recommendations:2014 Update

Background

• Ensuring that healthcare personnel (HCP) are protected against vaccine preventable diseases (VPDs) is an essential part of occupational health programs:

Prevents transmission of VPDs and eliminates unnecessary work restrictions

Safeguards the health of HCP and protects patients from exposure to infected HCP

Reduces both number of susceptible HCP and risks for transmission of VPDs to other workers and patients

Rationale

• Prevention of illness through comprehensive employee immunization programs is far more cost-effective than case management and outbreak control

• Facility mandated immunization programs, which include both newly hired and currently employed persons, are more effective than voluntary programs in ensuring that susceptible persons are vaccinated

• There are no federal or California state rules mandating immunization of HCP

How vaccines

have changed the world in one

graphic

(2010 data)

Vaccination programs

1. Maintenance of complete immunization records

2. Policies for catch-up vaccination3. Work restrictions for exposed susceptible

employees4. Control of outbreaks5. Additional vaccines may be indicated for

laboratory employees or for employees who travel to other parts of the world to perform research or healthcare work (e.g., as medical volunteers in a humanitarian effort)

Where do U.S. immunization recommendations come from?

• 15 experts selected by the U.S. Secretary of HHS to provide advice and guidance to CDC on the control of vaccine preventable diseases; the only entity in the federal government that makes such recommendations

• Develops written recommendations for routine administration of vaccines to children and adults in the civilian population; recommendations include age for vaccine administration, number of doses/dosing intervals, and precautions and contraindications

• Also makes immunization recommendations for HCP

Advisory Committee on Immunization Practices (ACIP)

ACIP recommendations for HCP

• Employer decisions about which ACIP recommended vaccines to include in HCP immunization programs have typically been made by considering the: Likelihood of HCP exposure to vaccine

preventable diseases and the potential consequences of not vaccinating HCP

Nature of employment (type of contact with patients/residents and their environment)

Characteristics of the patient/resident population the facility serves

Newest ACIP compendium of recommendations for HCP, 2011

Most recent ACIP recommendationsImmunization of healthcare personnel, 2011 http://www.cdc.gov/mmwr/preview/mmwrhtml/rr6007a1.htm

Diphtheria, tetanus, pertussis, 2006 and 2011 updatehttp://www.cdc.gov/mmwr/preview/mmwrhtml/rr5517a1.htmhttp://www.cdc.gov/mmwr/preview/mmwrhtml/mm6001a4.htm

A Comprehensive Immunization Strategy to Eliminate Transmission of Hepatitis B Virus Infection in the United States—Part 2: Immunization of Adults, 2006 http://www.cdc.gov/mmwr/PDF/rr/rr5516.pdf

CDC Guidance for Evaluating Health-Care Personnel for Hepatitis B Virus Protection and for Administering Postexposure Management, 2013http://www.cdc.gov/mmwr/preview/mmwrhtml/rr6210a1.htm

Prevention and Control of Seasonal Influenza with Vaccines, 2013http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6332a3.htm

Influenza vaccine, healthcare personnel, 2006http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5502a1.htm

Prevention of Measles, Rubella, Congenital Rubella Syndrome, and Mumps, 2013http://www.cdc.gov/mmwr/preview/mmwrhtml/rr6204a1.htm

Prevention and Control of Meningococcal Disease, 2013http://www.cdc.gov/mmwr/preview/mmwrhtml/rr6202a1.htm

Mumps, 2006 http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5522a4.htm

Varicella, 2007http://www.cdc.gov/mmwr/pdf/rr/rr5604.pdf

2014 ACIP adult immunization recommendationshttp://www.cdc.gov/vaccines/schedules/downloads/adult/adult-schedule.pdf

Recommended vaccinations indicated for adults based on medical and other indications – U.S.,

2014

CDC definition of HCP

• All paid and unpaid persons working in healthcare settings who have the potential for exposure to patients with influenza, infectious materials, including body substances, contaminated medical supplies and equipment, or contaminated environmental surfaces.

• HCP might include (but are not limited to): physicians, nurses, nursing assistants, therapists,

technicians, emergency medical service personnel, dental personnel, pharmacists, laboratory personnel, autopsy personnel, students and trainees, contractual staff not employed by the health-care facility, and persons (e.g., clerical, dietary, housekeeping, maintenance, and volunteers) not directly involved in patient care but potentially exposed to infectious agents that can be transmitted to and from HCP

Required immunizations for California HCP

• There are no federal or California state requirements mandating immunization or immunity to VPDs

• Some healthcare facilities require immunizations/immunity to specific VPDs as a condition of employment

• Some California local health officers have written orders mandating influenza vaccine for HCP working in facilities in their jurisdictions

Cal/OSHA Bloodborne Pathogen standard

• Vaccine that is required to be offered* per the Bloodborne Pathogen Standard

Hepatitis B vaccine – three doses

* To all employees who are exposed to blood or other potentially infectious materials as part of their job duties. If vaccine is declined, a declination form must be signed.

Cal/OSHA Aerosol Transmissible Diseases (ATD) standard

• Which California employees are covered by the ATD Standard?

Employees whose exposure from work activity or working conditions is reasonably anticipated to create an elevated risk of contracting any disease caused by aerosol-transmissible pathogens if protective measures are not in place

“Elevated” risk means higher than what is considered ordinary for employees having direct contact with the general public outside of the facilities, service categories, and operations listed in the standard http://www.dir.ca.gov/Title8/5199.html

Diseases covered by the ATD standard

• Applies to diseases classified by CDC’s Healthcare Infection Control Advisory Committee (HICPAC) as either droplet or airborne* Novel or unknown pathogens considered

airborne Only “reportable diseases” under Title 17†

require exposure investigation*2007 Guideline for Isolation Precautions: Preventing Transmission of Infectious Agents in Healthcare Settings http://www.cdc.gov/hicpac/2007IP/2007isolationPrecautions.html

†California reportable diseaseshttp://www.cdph.ca.gov/HealthInfo/Documents/Reportable_Diseases_Conditions.pdf

Occupational exposure• In each included work setting covered by

the standard, it is presumed that some employees have occupational exposure to ATDs; for a particular employee it depends on tasks, activities, and the environment

• Includes having contact with, or being within the exposure range of cases or suspected cases of aerosol-transmissible diseases

• Employers must identify employees with occupational exposure in order to take protective measures

Vaccines that are required to be offered* per the ATD standard

Vaccine • Influenza • Measles• Mumps• Rubella • Tetanus, diphtheria,

and acellular pertussis (Tdap)

• Varicella-zoster (VZV)

Schedule• One dose

annually• Two doses• Two doses• One dose• One dose

• Two doses* To all susceptible employees who might be exposed. If vaccine is declined, a declination form must be signed.

Seasonal Influenza

Annual influenza vaccination

• Offer to all eligible HCP at no cost• Educate re: vaccination benefits and

consequences of influenza illness for themselves and their patients

• Obtain signed declination forms• Monitor coverage including ward, unit, and

specialty-specific coverage rates; report vaccination rates to CDPH

• Use HCP influenza vaccination coverage as a measure of patient safety quality program

• Mandate vaccination??

Influenza and HCP• On average, ~5% to 20% of the U.S. population

becomes infected with influenza each year

• 23% of HCP had documented serologic evidence of influenza infection after a mild influenza season; 59% could not recall having influenza

• >75% of HCP with influenza-like illness (ILI) continued to work in hospital

• Persons are infectious before the onset of influenza symptoms

• Data for the 2013-2014 influenza season indicate that influenza vaccine effectiveness against influenza A was about 62% for all age groups combined

Barriers to influenza vaccination • Fear of vaccine side effects (particularly influenza-

like illness symptoms)

• Perceived ineffectiveness of the vaccine

• Perceived medical contraindication (typically not valid)

• Perceived low likelihood of contracting influenza

• Fear of needles

• Insufficient time or inconvenience

CDC influenza vaccine information for HCP: http://www.cdc.gov/flu/HealthcareWorkers.htm?s_cid=ccu091310_014 http://www.thecommunityguide.org/worksite/flu-hcw.html

Strategies used by nursing homes to encourage influenza vaccination among

their employees

§ Strategies associated with LTCF staff influenza vaccination rates >60%

SOURCE: National Nursing Home Survey; 2004

Available at: http://www.cdc.gov/nchs/nnhs.htm

Mandatory influenza vaccination

• Seattle: Virginia Mason – in 2005, first U.S. hospital to mandate influenza vaccination or mask wearing during influenza season

• St. Louis: Barnes-Jewish – in 2008, first U.S. hospital system to mandate influenza vaccination and terminate noncompliant employees

• New York: in 2009, emergency regulation (later withdrawn) required seasonal and pandemic H1N1 vaccination of personnel in hospitals, home care, hospice, and diagnostic/treatment facilities

• California: hospitals must offer vaccine at no cost to employees Vaccination or written declination required per SB 739 and the ATD

standard Public reporting of vaccination rates via CDC’s National Healthcare

Safety Network (NHSN) required Some CA hospitals began mandating vaccination or mask wearing

during the 2009 H1N1 pandemic At least 23 CA local health officers have mandated influenza vaccine

or mask wearing for HCP working in their jurisdictions http://www.cdph.ca.gov/programs/cclho/Pages/MandatoryofRecommendedInfluenzaVaccinationofHealthcareWorkers.aspx

National organizations with position statements on HCP influenza vaccine

• American Academy of Family Physicians (AAFP) Mandatory Influenza Vaccination of Health Care Personnel, 2011

• American Academy of Pediatrics (AAP) Policy Statement–Recommendation for Mandatory Influenza Immunization of All Health Care Personnel, 2010

• American Hospital Association (AHA): AHA Endorses Patient Safety Policies Requiring Influenza Vaccination of Health Care Workers, 2011

• American Medical Directors Association (AMDA) Position Statement: Mandatory Immunization for Long Term Care Workers, 2011

• American Pharmacists Association (APhA): Requiring Influenza Vaccination for All Pharmacy Personnel, 2011

• American Public Health Association (APHA) Policy Statement: Annual Influenza Vaccination Requirements for Health Workers, 2010

• Association for Professionals in Infection Control and Epidemiology, Inc. (APIC): Influenza Vaccination Should Be a Condition of Employment for Healthcare Personnel, Unless Medically Contraindicated, 2011

• Infectious Diseases Society of America (IDSA) Policy on Mandatory Influenza Immunization of Heath Care Workers, 2010

• National Association of County and City Health Officials (NACCHO): Influenza Vaccinations for Healthcare Personnel Policy, 2012

• National Business Group on Health: Hospitals Should Require Flu Vaccination for all Personnel to Protect Patients’ Health and Their Own Health, 2011

• National Foundation for Infectious Diseases (NFID), 2010• National Patient Safety Foundation (NPSF) Supports Mandatory Flu Vaccinations for

Healthcare Workers, 2009• Society for Healthcare Epidemiology of America (SHEA) Position Paper: Influenza

Vaccination of Healthcare Personnel, 2010

Joint Commission - 2011• Standard IC.02.04.01* - The organization:

establishes an annual influenza vaccination program that is offered to staff, including contracted staff

educates staff about, at a minimum, the influenza vaccine; non-vaccine control and prevention measures; and the diagnosis, transmission, and impact of influenza

sets incremental influenza vaccination goals, consistent with achieving the 90% rate established in the national influenza initiatives for 2020;

measures vaccination rates and has a written description of the methodology used to determine rates (CDC/NQF measure does not include contracted staff)

collects and reviews the reasons given by staff for declining influenza vaccination at least annually

improves its vaccination rates according to its established, internal goals at least annually

*Standard IC.02.04.01 does not mandate influenza vaccination for staff as a condition of Joint Commission accreditation

People at higher risk for developing influenza related complications• Children younger than 5, but especially children

younger than 2 years of age

• Adults 65 years of age and older

• Pregnant women

• American Indians and Alaskan Natives

• People with asthma, neurological and neurodevelopmental conditions*, chronic lung disease, heart disease, blood, kidney, liver and metabolic disorders, weakened immune systems, morbid obesity (BMI ≥40) and people <19 years of age who are receiving long-term aspirin therapy*particularly conditions that can compromise respiratory function, the handling of respiratory secretions, or increase the risk for aspiration

Types of influenza vaccine• Inactivated influenza vaccine (IIV) – may be

trivalent; 2 A strains and 1 B strain (IIV3) or quadrivalent; 2 A strains and 2 B strains (IIV4).

• Live attenuated influenza vaccine (LAIV) – available vaccine is quadrivalent (LAIV4).

• Recombinant influenza vaccine (RIV) – available vaccine is trivalent (RIV3).

• There are two antigenically distinct lineages of influenza B viruses and immunization against B virus strains of one lineage provides only limited cross-protection against strains in the other lineage.

• Because of this and the difficulty of predicting which B virus lineage will predominate during a given season, quadrivalent vaccines have been developed.

Other formulations of inactivated vaccines• All inactivated vaccine preparations contain the

same quantity of hemagglutinin (15 µg per vaccine virus strain per 0.5 mL dose; 45 µg total), except Fluzone Intradermal and Fluzone High-Dose (Sanofi Pasteur)

Fluzone Intradermal is indicated for persons aged 18 through 64 years and contains 9 µg of hemagglutinin per vaccine virus strain (27 µg total) in a 0.1 mL dose

Fluzone High-Dose is indicated for persons aged ≥65 years and contains 60 µg of hemagglutinin per vaccine virus strain (180 µg total) in a 0.5 mL dose

• Within specified age indications, ACIP expresses no preference for any given IIV formulation over another

Inactivated influenza vaccines (IIV) vs. live attenuated influenza vaccine (LAIV)• Either IIV3 or IIV4 or LAIV can be used to reduce the risk for

influenza among HCP

• LAIV is approved for use only among nonpregnant healthy persons aged 5-49 years; contraindications include: pregnancy, asthma, reactive airways disease or other chronic

disorders of the pulmonary or cardiovascular systems; other underlying medical conditions, including metabolic diseases such as diabetes, renal dysfunction, and hemoglobinopathies; known or suspected immunodeficiency diseases or receipt of immunosuppressive therapies

• Available data indicate that persons vaccinated with LAIV can shed vaccine viruses for >2 days after vaccination

• HCP who work with severely immunocompromised patients (e.g., hematopoietic stem cell transplant recipients) who require a protected environment should not receive LAIV (if given LAIV, HCP should have no contact with such patients for 7 days)

• Personnel who may administer LAIV Severely immunosuppressed persons should not administer

LAIV because introduction of low levels of vaccine virus into the environment probably cannot be avoided when administering LAIV. However, other persons with conditions placing them at high risk for influenza complications (e.g., pregnant women, persons with asthma, and persons aged >50 years) may administer LAIV.

• LAIV and the use of influenza antiviral medications Because influenza antivirals reduce replication of influenza

viruses, LAIV should not be administered until 48 hours after cessation of influenza antiviral therapy, and influenza antiviral medications should not be administered for 2 weeks after receipt of LAIV.

 

More on LAIV

Influenza vaccination of persons with a history of egg allergy - 1• Persons with a history of egg allergy who have experienced only hives after

exposure to egg should receive influenza vaccine. Because relatively few data are available for use of LAIV in this setting, IIV or RIV should be used. RIV is egg-free and may be used for persons aged 18–49 years who have no other contraindications. However, IIV (egg- or cell-culture based) also may be used, with the following additional safety measures: Vaccine should be administered by a health-care provider who is familiar

with the potential manifestations of egg allergy; and Vaccine recipients should be observed for at least 30 minutes for signs

of a reaction after administration of each vaccine dose.• Other measures, such as dividing and administering the vaccine by a two-

step approach and skin testing with vaccine, are not necessary.• Persons who report having had reactions to egg involving such symptoms as

angioedema, respiratory distress, lightheadedness, or recurrent emesis; or who required epinephrine or another emergency medical intervention, particularly those that occurred immediately or within a short time (minutes to hours) after egg exposure, are more likely to have a serious systemic or anaphylactic reaction upon re-exposure to egg proteins. These persons may receive RIV3, if aged 18 through 49 years and there are no other contraindications. If RIV3 is not available or the recipient is not within the indicated age range, such persons should be referred to a physician with expertise in the management of allergic conditions for further risk assessment before receipt of vaccine.

Influenza vaccination of persons with a history of egg allergy - 2• All vaccines should be administered in settings in which personnel and

equipment for rapid recognition and treatment of anaphylaxis are available. ACIP recommends that all vaccination providers should be familiar with the office emergency plan.

• Some persons who report allergy to egg might not be egg-allergic. Those who are able to eat lightly cooked egg (e.g., scrambled egg) without reaction are unlikely to be allergic. Egg-allergic persons might tolerate egg in baked products (e.g., bread or cake). Tolerance to egg-containing foods does not exclude the possibility of egg allergy. Egg allergy can be confirmed by a consistent medical history of adverse reactions to eggs and egg-containing foods, plus skin and/or blood testing for immunoglobulin E antibodies to egg proteins.

• For persons who have no known history of exposure to egg, but who are suspected of being egg-allergic on the basis of previously performed allergy testing, consultation with a physician with expertise in the management of allergic conditions should be obtained before vaccination. Alternatively, RIV3 may be administered if the recipient is aged 18 through 49 years.

• A previous severe allergic reaction to influenza vaccine, regardless of the component suspected to be responsible for the reaction, is a contraindication to future receipt of any influenza vaccine.

• Two adult vaccines that are manufactured using newer technologies that minimize or avoid entirely the use of eggs are now available: Flucelvax, which is produced using cell culture technology, and FluBlok, which contains recombinant HA.

Recommendations on influenza vaccination of persons who report allergy to eggs

Abbreviations: IIV = inactivated influenza vaccine; RIV3 = recombinant influenza vaccine, trivalent* Persons with egg allergy might tolerate egg in baked products (e.g. bread or cake). Tolerance to egg-containing foods does not exclude the possibility of egg allergy. For persons who have no known history of exposure to egg but who are suspected of being egg-allergic on the basis of previously performed allergy testing, consultation with a physician with expertise in the management of allergic conditions should be obtained prior to vaccination. Alternatively, RIV3 may be administered if the recipient is aged 18 through 49 years.

Contraindication and precautions• Contraindication

A previous severe allergic reaction to influenza vaccine, regardless of the component suspected to be responsible for the reaction

• Precautions Moderate or severe acute illness with or

without fever Guillain-Barré Syndrome within 6 weeks

following a previous dose of influenza vaccine

Hepatitis B

Hepatitis B vaccination: HCP• Any person who performs tasks

involving contact with blood, blood-contaminated body fluids, other body fluids, or sharps should be vaccinated against hepatitis B Highly immunogenic – seroconversion

~95%

• Incidence among HCP since mid-1990s is lower than general population due to vaccination and standard precautions

Updated U.S. P.H.S. Guidelines for the Management of Occupational Exposures to HBV, HCV, and HIV and Recommendations for Post-exposure Prophylaxis. MMWR 50 (RR11) - 6/29/01

http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5011a1.htm

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Vaccine Recommended for HCP

OSHA Requirement

s

Hepatitis B

• HCP with potential for exposure to blood or body fluids should be immunized for hepatitis B with the 3-dose vaccine series if they have not already received it

• Newly immunized HCP should be tested 1-2 months after the last dose of vaccine series to determine if they are immune anti-HBs >10 mIU/mL = immune

Hepatitis B testing for immunity after vaccination• Anti-HBs <10 mIU/mL revaccinate

3 doses followed by testing after third dose more practical than testing after 1 or more doses of vaccine

• Anti-HBs <10 mIU/mL after revaccination test for HBsAg HBsAg positive provide appropriate management HBsAg negative susceptible to HBV infection

– counsel re: precautions to prevent HBV infection– HBIG postexposure prophylaxis for any known or

likely parenteral exposure to HBsAg-positive blood

• Periodic titers or booster doses of vaccine not recommended - protection is long lasting

Previously vaccinated HCP without evidence of immunity• Over time, an increasing number of persons

entering the healthcare workforce will have received routine vaccination as infants, children, or adolescents; most will have no documentation of seroprotection

• Persons immunized for hepatitis B in the past are less likely to have measurable anti-HBs than those vaccinated more recently

• In 2013 CDC issued updated guidance on pre- and post-exposure testing and follow-up for hepatitis B, this guidance can be accessed at: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr6210a1.htm

2013 CDC guidance• HCP with documentation of 3 doses of hepatitis B

vaccine, but no documentation of immunity may undergo anti-HBs testing upon hire or matriculation.

• This approach is most appropriate for settings with HCP-trainees and HCP in occupations with higher risk of exposure (e.g., surgeons), and when the prevalence of HBV is increased in the patient population served.

• Alternatively, employers may choose to perform anti-HBs testing only if such HCP later report a blood or body fluid exposure. All employees should receive training to recognize and report exposures.

California hospital survey, 2012How does your institution currently manage new HCP who have documentation of a complete hepatitis B

vaccine series but no documentation of post-vaccination serologic testing?

Perc

ent

Which do you think is the best approach?

Testing for hepatitis B infection• Regardless of immunization history, it may be

prudent to test HCP and trainees in certain high-risk groups for HBsAg and anti-HBc/anti-HBs to determine their infection status:

Those born in countries with high and intermediate endemicity for hepatitis B

Unvaccinated U.S.-born HCP whose parents were born in regions of high endemicity for hepatitis B

HIV-positive HCP HCP who disclose having engaged in or currently

engaging in high-risk sexual or substance abuse behaviors

HCP who require immunosuppressive therapy or who are on hemodialysis http://www.cdc.gov/mmwr/pdf/rr/rr5516.pdf

Hepatitis B infected HCP

• Chronic hepatitis B infection is not grounds for exclusion from healthcare practice or training, see: The Society for Healthcare Epidemiology of

America’s “Guideline for Management of Healthcare Workers Who Are Infected with Hepatitis B Virus, Hepatitis C Virus, and/or Human Immunodeficiency Virus” at:

http://www.shea-online.org/GuidelinesResources/Guidelines/Guideline/ArticleId/46/Guideline-for-Management-of-Healthcare-Workers-Who-Are-Infected-with-Hepatitis-B-Virus-Hepatitis-C-V.aspx

Updated CDC Recommendations for the Management of Hepatitis B Virus–Infected Health-Care Providers and Students at: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr6103a1.htm

HBV postexposure prophylaxis

Updated U.S. Public Health Service Guidelines for the Management of Occupational Exposures to HBV, HCV, and HIV and Recommendations for Post-exposure Prophylaxis.

2001.http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5011a1.htm

Measles

Measles - basics• Rash illness, historically a childhood infection

with 2-4 year epidemic cycle; most cases in winter/spring

• Complications may include otitis media, pneumonia, encephalitis, miscarriage, and death

• No endemic transmission in the U.S. at this time

Measles • In the decade before measles vaccine was

licensed in 1963, 3–4 million people were infected in the U.S. each year 400–500 died 1,000 suffered permanent brain damage or deafness 4,000 had encephalitis 7,000 had seizures 48,000 were hospitalized 150,000 had respiratory complications (pneumonia)

• Nearly all children were infected by the age of 15

• Widespread use of measles vaccine led to a greater than 99% reduction in measles cases in the U.S. compared with the pre-vaccine era

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Measles• Elimination of endemic measles was achieved in

the U.S. in 2000 and in North and South America in 2002 and is a public health success model for immunization programs in the developed world

• The last nationwide outbreak in U.S. was 1988-1991 when there were 17,000 cases in California with 70 deaths

• Introduction of 2nd dose of vaccine in 1989 and federal “Vaccines for Children” program in 1993

• Two doses of MMR vaccine offer >99% protection from disease; however because measles is so infectious, very high population immunity (92-95%) is necessary to interrupt transmission

Measles - epidemiology

• Currently, most U.S. measles cases are related to international travel or contact with ill travelers

• Measles is still endemic in Europe with large outbreaks in 2010-2011; including a large (>15,000 cases) outbreak in France in 2011

• During 2012, large measles outbreaks were reported by the Democratic Republic of the Congo, India, Indonesia, Ukraine, Somalia, Sudan, Pakistan, and Romania; China reported 6183 cases, a historic low

• In 2012, there were 226,722 cases worldwide with an estimated 122,000 deaths; a 73% decrease in cases and a 78% decrease in deaths since 2000 as 1 dose measles vaccine coverage increased from 73 to 84%

Measles transmission • Measles is transmitted via the airborne

route and is thought to be the most infectious communicable disease; R0 =15-17

• Measles transmission has been documented in physician offices, emergency rooms, and hospital wards; HCP have been infected in recent outbreaks

• Good documentation and high levels of immunity minimize the amount of follow-up that needs to be done in the event of an exposure Record review for hundreds to thousands staff Serologic testing and vaccination

Presumptive evidence of immunity to measles• Documentation of vaccination with 2 doses of live

measles virus-containing vaccine*, or• Laboratory evidence of immunity†, or • Laboratory confirmation of disease, or• Birth before 1957§

*The first dose of MMR vaccine should be administered on or after age 12 months; the second dose of measles- or mumps-containing vaccine should be administered no earlier than 28 days after the first dose.

† Measles IgG in serum; equivocal results should be considered negative.§ Since some persons born before 1957 will be susceptible to measles, CDPH recommends that

immunity be assessed if such HCP are exposed to measles. During a measles outbreak, 2 doses of MMR are recommended for unvaccinated HCP born before 1957 who do not have evidence of measles immunity.

Respiratory protection

• Per Cal/OSHA requirements, regardless of their immune status, all HCP must use respiratory protection at least as effective as an N95 respirator when in contact with measles patients

Measles exposures

• If an exposure to measles occurs in a healthcare facility CDPH recommends that all exposed HCP, regardless of age, have: serological evidence of immunity to measles

(IgG+); or documentation of two doses of measles

containing vaccine (preferably MMR) after first birthday

• Reviewing HCP immune status for measles and testing for immunity/providing vaccine after an exposure results in considerable work for healthcare facilities

HCP measles exposure• MMR vaccine for postexposure prophylaxis

MMR may be given <72 hours of exposure to those with 1 or no documented doses of MMR, if not contraindicated.

• Immune globulin (IG) for postexposure prophylaxis Pregnant women without evidence of measles immunity should receive 400

mg/kg of IG given intravenously (IGIV). Severely immunocompromised* persons, irrespective of evidence of

measles immunity, should receive 400 mg/kg of IGIV. For persons who are already receiving IGIV therapy, >400 mg/kg <3 weeks

before exposure should be sufficient to prevent infection. IGIM (0.5 mL/kg of body weight; maximum dose = 15 mL) can be given to

other persons who do not have evidence of measles immunity, but priority should be given to persons exposed in settings with intense, prolonged, close contact (e.g., household, child care, classroom, etc.).

*Severely immunocompromised patients include patients with severe primary immunodeficiency; patients who have received a bone marrow or stem cell transplant until at least 12 months after finishing all immunosuppressive treatment, or longer where the patient has developed graft-versus-host disease; patients on treatment for ALL within and until at least six months after completion of immunosuppressive chemotherapy; and patients with a diagnosis of AIDS or HIV-infected persons with CD4 percent <15% (all ages) or CD4 <200 lymphocytes /mm3 (age >5 years) and those who have not received MMR vaccine since receiving effective ART; some experts would include HIV-infected persons who lack recent confirmation of immunologic status or measles immunity. IG may be given to exposed susceptible people of any age <6 days of exposure.

 It is unknown if IG prolongs the incubation period. If measles symptoms occur <28 days of exposure, persons who have received IG

should self-isolate and contact their local health department.

One source of IG is FFF Enterprises, which can be reached 24/7 at: 1-800-843-7477.

RECOMMENDED FOLLOW-UP FOR HIGH RISK1 MEASLES CONTACTS

Category IgG testing

Postexposure prophylaxis2

Quarantine3 Symptom watch

Two documented doses of MMR vaccine (~1% will be susceptible)

No No No Passive

Measles IgG positive (<1% will be susceptible) No No No PassiveHave 1 documented dose of MMR vaccine (5% will be susceptible) or no documented doses of MMR

Yes No4 Yes Active

Born before 1957 (5% will be susceptible) Yes No4 Yes ActiveHistory of measles disease Yes No4 Yes ActiveUnknown or no documentation of measles immunity status

Yes No4 Yes Active

Measles IgG negative or known to be unvaccinated - Yes Yes ActiveReceived MMR vaccine <72 hours of exposure5 - - Yes ActiveReceived immune globulin ≤6 days of exposure - - Yes Active

1. A high risk contact is defined as an exposed contact who is at high risk of infection or measles complications (pregnant or immunocompromised) from measles or who works or lives in a sensitive setting or a setting where transmission is likely to occur (e.g., healthcare, child care, or congregate setting) or who had significant exposure to the case (household contact). Ensure documentation of immunity (documented IgG+ or 2 documented doses MMR) in all high risk persons.Postexposure prophylaxis is either IG or MMR vaccine. IG may be administered <6 days of exposure to susceptible contacts of any age who did not receive MMR vaccine <72 hours of exposure. MMR vaccine should not be given until 5 months after IG in healthy people and until 6 months after IG in immunocompromised people. If it can be done rapidly, we recommend testing healthy contacts >12 months of age for measles IgG prior to administering IG.If symptoms consistent with measles develop, exposed person should be isolated. If there is concern about whether measles symptoms will be reported or if there will be compliance with quarantine, periodic calls to the exposed person to monitor for development of measles symptoms are recommended (see above for symptom watch time period and additional guidance).If an exposed person is identified as susceptible through serologic testing (measles IgG negative), then postexposure prophylaxis should be offered if it is within the recommended time period; alternatively if immune status is unknown and laboratory testing cannot be done, postexposure prophylaxis can be considered.If measles IgG status is unknown, persons >12 months of age who receive MMR vaccine as postexposure prophylaxis should have blood drawn and tested at the time of MMR administration.

Healthcare-associated transmission of measles in U.S. healthcare facilities• Healthcare-associated transmission of

measles is well documented

• Measles can be transmitted up to two hours after an infectious patient has left the area

• 11% of 127 cases were transmitted in healthcare settings; considerable economic cost and public health effort to contain (~$100,000 to $400,000)

• Four cases of measles were acquired in a San Diego County pediatrician’s office

• The largest nosocomial measles outbreak in 20 years occurred in Arizona in 2008

Arizona measles outbreak, 2008• In February 2008, an infected Swiss traveler sparked a

measles outbreak involving 14 cases, 7 of whom were infected in healthcare facilities; measles was not suspected until after she had been hospitalized, unisolated, for 2 days

• Of the 11 secondary cases who accessed healthcare, 10 did not receive a prompt measles diagnosis after rash onset and only 1 was masked and isolated promptly

• 8231 people were potentially exposed; 4793 were hospital or clinic patients and 2868 were HCP

• 25% of 7195 screened HCP lacked evidence of measles immunity; 1583 underwent IgG testing and 121 (11%) of 1077 HCPs born >1957 and 18 (4%) of 506 HCPs born <1957 were seronegative, including 1 who acquired measles

• Two hospitals spent ~$800,000 responding to and containing the seven measles cases in their facilities

Mumps

Mumps in healthcare settings

• In recent outbreaks involving hospitals and long-term care facilities with adolescent and young adult patients, infection control failures resulted in nosocomial transmission

• Exposure to mumps in healthcare settings results in added economic costs associated with furlough or reassignment of staff members from patient-care duties or the closure of wards

• In Tennessee in 1986-87, nosocomial transmission of mumps occurred in two hospital ERs infecting 6 HCP and in two long-term care facilities infecting 9 patients

Presumptive evidence of immunity to mumps

• Documentation of vaccination with 2 doses of live mumps virus-containing vaccine*, or

• Laboratory evidence of immunity†, or • Laboratory confirmation of disease, or• Birth before 1957§

*The first dose of MMR vaccine should be administered on or after age 12 months; the second dose of measles- or mumps-containing vaccine should be administered no earlier than 28 days after the first dose.

†Mumps IgG in serum; equivocal results should be considered negative.§Since some persons born before 1957 will be susceptible to mumps, CDPH recommends that

immunity be assessed if such HCP are exposed to mumps. During a mumps outbreak, 2 doses of MMR are recommended for unvaccinated HCP born before 1957 who do not have evidence of mumps immunity.

Mumps vaccination

• All persons who work in healthcare facilities should be immune to mumps HCP born during or after 1957 2 doses No vaccination/immunity 2 doses (>28 days

apart) Only 1 dose previously second dose Birth before 1957 is only presumptive evidence

of immunity; consider 1 dose for unvaccinated workers without laboratory evidence of immunity

During an outbreak, 2 doses of vaccine recommended for workers born before 1957 who do not have evidence of immunity

Mumps epidemiology

• Post-licensure studies of 1 dose of mumps vaccine showed it was 78%-91% effective in preventing clinical mumps

• Late 1980s - early 1990s, mumps outbreaks observed in schools with extremely high (>95%) vaccination coverage, suggesting that 1 dose of mumps vaccine is insufficient to prevent mumps outbreaks in schools

• Since the 1989 2-dose MMR requirement, incidence of mumps disease has decreased and studies of vaccine effectiveness during outbreaks suggest substantially higher levels of protection with a second dose of MMR

Mumps prevention and control

• During an outbreak, healthcare facilities should strongly consider recommending 2 doses of mumps vaccine to unvaccinated workers born before 1957 who do not have evidence of mumps immunity

• Reviewing HCP immune status for mumps and providing serologic testing and vaccine during an outbreak is difficult

• Facilities might consider reviewing immune status of HCP routinely and providing appropriate vaccinations, including a second dose of mumps vaccine, in conjunction with annual activities such as influenza vaccination or TB testing

• Because not all people with 2 doses of mumps vaccine are protected, HCP should be advised to immediately exclude themselves from work if symptoms develop

http://www.cdc.gov/mumps/prev-control-settings/index.html

HCP mumps exposure• HCP without presumptive evidence of immunity

There is no postexposure prophylaxis Exclude from the 12th day after the first unprotected

exposure through the 25th day after the last exposure

• HCP with one dose of vaccine May remain at work and should receive the second dose as

soon as possible, but no sooner than 28 days after the first Should be educated about mumps symptoms, including

non-specific presentations, and notify occupational health if symptoms develop

• HCP with presumptive evidence of immunity May remain at work, but because some vaccinated people

develop infection, should be educated about mumps symptoms and notify occupational health if symptoms develop

Rubella

Rubella epidemiology• Rubella vaccines were first licensed in 1969 and

rubella was declared eliminated in the U.S. in 2004

• Rubella cases in the U.S. are now imported from regions of the world where rubella is not controlled

• Rubella is typically a mild illness; the concern is harm (deafness, seizures, encephalitis, and developmental delays) to the developing fetus when pregnant women are infected

• More than 20,000 babies were born in the U.S. with congenital rubella syndrome (CRS) during a 1964-65 outbreak before the vaccine was licensed

Current rubella outbreak

• The number of rubella cases in Japan, especially in Tokyo, has been increasing in 2013

• Approximately 70% of reported cases of rubella involve middle-aged men, partly because boys were not vaccinated against rubella by the national immunization program until 1995

• To prevent congenital rubella syndrome, the vaccination of women of childbearing age and their partners is currently a national priority

Rubella case – Japan 2013A 23-year-old unvaccinated woman presented to the ED after 1 day of fever, sore throat, arthralgia, and rash. Diffuse erythema (Panel A) that blanched on pressure was noted over the face, neck, trunk, and arms,

along with posterior cervical lymphadenopathy. The next day, the fever and rash subsided, but she reported pain in the oral cavity.

Examination revealed petechial hemorrhages on the soft palate (Panel B) that disappeared spontaneously in 2 days.

Presumptive evidence of immunity to rubella• Documentation of vaccination with 1 dose

of live rubella virus-containing vaccine*, or• Laboratory evidence of immunity†, or • Laboratory confirmation of disease, or• Birth before 1957§ (except premenopausal

women who could become pregnant)

*The first dose of MMR vaccine should be administered on or after age 12 months; the second dose of measles- or mumps-containing vaccine should be administered no earlier than 28 days after the first dose.

†Rubella IgG in serum; equivocal results should be considered negative.§Since some persons born before 1957 will be susceptible to rubella, CDPH

recommends that immunity be assessed if such HCP are exposed to rubella. During a rubella outbreak, 1 dose of MMR is recommended for unvaccinated HCP born before 1957 who do not have evidence of rubella immunity.

Presumptive evidence of immunity to rubella, continued• HCP who can provide documentation of

serological evidence of rubella immunity (e.g., via prenatal testing) do not need to be retested and should be considered immune

• The principle of “once immune, always immune” also applies to measles, mumps and hepatitis B

MMR vaccination for HCP born before 1957• HCP born before 1957 are generally presumed to

be immune to measles, mumps, and rubella, but not all are

• Consider recommending 2 doses of MMR vaccine routinely for unvaccinated HCP born before 1957 who lack laboratory evidence of measles, mumps or rubella immunity or laboratory confirmation of disease

• During an outbreak of measles or mumps, two doses of MMR vaccine are recommended for unvaccinated HCP born before 1957 who lack laboratory evidence of immunity or laboratory confirmation of disease; one dose of MMR recommended during a rubella outbreak

Measles, mumps and rubella immunity testing• When testing immunity, please do not select a panel

that includes IgM testing; this results in false positives

• Testing for serologic evidence of immunity to measles, mumps or rubella (IgG testing) is not recommended for HCP who have two documented doses of MMR vaccine or other acceptable evidence of immunity

• If testing is inadvertently performed on HCP with documentation of two doses of MMR vaccine and the worker is IgG negative or equivocal for measles, mumps or rubella, ACIP recommends that the test be assumed to be falsely negative and that the worker be presumed immune and not given another dose of MMR vaccine, i.e., documented age-appropriate vaccination supersedes the results of subsequent serologic testing

Varicella

Varicella among HCP

• Nosocomial transmission of is varicella is well-recognized

• Sources Patients, hospital staff, and visitors with

varicella or herpes zoster (shingles)

• Airborne transmission of varicella has been demonstrated Varicella has occurred in susceptible persons

who had no direct contact with index case Virus detected in air Herpes zoster may also be airborne (?)

2007 ACIP recommendations• Serologic screening before vaccination

Testing unvaccinated HCP with a negative or uncertain history of varicella is likely to be cost-effective; or

Test all HCP, because small proportion with positive history of disease might be susceptible

• Routine testing after 2 doses of vaccine is not recommended Available commercial assays not sensitive enough and

are likely to be falsely negative In sensitive tests, 99% of adults develop antibodies

after 2nd dose If testing is done, IgG+ results can be relied upon

http://www.cdc.gov/mmwr/pdf/rr/rr5604.pdf

Evidence of immunity to varicella in HCP

• Documentation of two doses of vaccine

• Laboratory evidence of immunity or laboratory confirmation of disease

• Diagnosis or verification of history of varicella disease or herpes zoster (shingles) by a healthcare provider If an employee states they have had varicella or herpes zoster in

the past, a healthcare provider can interview the employee to determine if their history is compatible with one of these diagnoses; if so, this is considered evidence of immunity

• ACIP also states that “Institutions may elect to test all HCP regardless of disease history because a small proportion of persons with a positive history of disease might be susceptible”

Evidence of immunity to varicella, continued• Serologic evidence of VZV infection in 96%-97% of

U.S.-born adults aged 20-29 years and in 97%-99% of adults aged >30 years tested during 1998-1999

• U.S. birth before 1980 considered evidence of immunity except for HCP, pregnant women, and immunocompromised people

• For these three groups, certainty regarding immunity is desirable because of the possibility of nosocomial transmission to high-risk patients; transmission of the virus to the fetus, which might result in congenital varicella syndrome; and possibility of severe disease

Respiratory protection

• Per Cal/OSHA requirements, regardless of immune status, all HCP must use respiratory protection at least as effective as an N95 respirator when in contact with varicella patients

Varicella postexposure prophylaxis for HCP• Varicella vaccine may be effective in preventing

illness or modifying varicella severity if administered to unvaccinated persons within 3 days, and possibly up to 5 days, of exposure

• Although postexposure use of varicella vaccine has potential applications in hospital settings, pre-exposure vaccination preferred

• Varicella Zoster Immune Globulin (VariZIG) is recommended for pregnant and immunocompromised contacts without evidence of immunity

HCP varicella exposure

• HCP with 2 doses of varicella vaccine Monitor daily during days 10-21 after exposure to

determine clinical status Place on sick leave immediately if symptoms

occur

• HCP with 1 dose of varicella vaccine Give 2nd dose of vaccine <3-5 days of exposure After vaccination, management is similar to 2-

dose

• HCP without evidence of immunity Give 1st dose of vaccine <3-5 days of exposure Furlough days 10-21 after exposure

Transmission of vaccine virus from vaccine recipients with rash• Risk low; transmission has been

documented after exposures in households and long-term care facilities

• No cases documented after vaccination of HCP

• Consider precautions for HCP in whom rash occurs after vaccination

Avoid contact with persons without evidence of immunity at risk for severe disease and complications until all lesions resolve (i.e., are crusted over or fade away) or no new lesions appear in a 24-hour period

Pertussis

Pertussis in the United States• Least well controlled vaccine preventable disease

• Cyclical with peaks every 2-5 years – in 2010, California experienced an epidemic with >9,000 cases & 10 deaths

• Most severe disease occurs among infants <6 months of age; almost all deaths are in infants <3 months of age

• Studies have shown that ~half of the infants with pertussis were infected by a household member

• Immunity via vaccine or disease wanes over time; duration of protection from acellular pertussis vaccines wanes within several years: disease > whole cell vaccine > acellular vaccine

• Almost all adults are susceptible; very few adults have received Tdap, which was licensed in 2005

* Includes cases reported to CDPH as of 2/6/2012

Incidence of reported pertussis cases by year of onset – California, 1914-2011*

Number of reported pertussis cases by year of onset -- California 1947-2013*

Pertussis among HCP• Nosocomial spread of pertussis documented

Hospitals and EDs (pediatric and adult), clinics, LTCFs

• Sources Patients, HCP with hospital or community-acquired

pertussis, visitors or family members; up to 80 infections per index case

• Incidence in HCP ~7% per year

• 90% of pediatric hospitals reported HCP exposures over 5-year period; 11% reported infected physicians

Costs of controlling pertussis• $74,870-$174,327 per outbreak

• $42,000-$98,000/year for pertussis exposures Include identifying contacts among HCP and

patients, providing postexposure prophylaxis for asymptomatic close contacts, and evaluating, treating, and placing symptomatic HCP on administrative leave until they have received effective treatment

MMWR December 15, 2006;55(RR17)

http://www.cdc.gov/mmwr/PDF/rr/rr5517.pdf

Tdap vaccine • In 2005, Tdap (tetanus, diphtheria and acellular pertussis)

vaccine was licensed in the U.S. – no single antigen pertussis vaccine is available

• In 2006, ACIP recommended that HCP in hospitals and ambulatory care settings with direct patient contact receive a single dose of Tdap as soon as feasible if they have not previously received it – this was re-emphasized in 2011, “all HCP should receive Tdap as soon as feasible”

• HCP who have direct contact with infants <12 months of age or pregnant women should be strongly encouraged to be vaccinated

• Regardless of age, HCP without documentation of Tdap immunization should receive it – there is no minimum interval between the last dose of Td and Tdap

• Only one dose of Tdap is currently recommended, including for healthcare workers

Implementing a hospital Tdap program • Infrastructure exists in most hospitals

New HCP can be screened and vaccinated on employment

Tdap can be given at same time as influenza vaccine

Tiered approach option for existing HCP: priority given to those with contact with infants <12 months of age or pregnant women

• Pregnant women now recommended to receive Tdap during every pregnancy; birth hospitals should provide Tdap to new mothers who were not vaccinated during pregnancy (and other contacts)

• Emergency departments should use Tdap instead of Td for wound management

2011 ACIP recommendations on pertussis postexposure prophylaxis for vaccinated HCP

• Data on the need for postexposure prophylaxis in Tdap-vaccinated HCP are inconclusive

• Postexposure prophylaxis is recommend for all HCP who have unprotected exposure to pertussis and are likely to expose a patient at risk for severe pertussis (e.g., hospitalized neonates)

• Other HCP should either receive postexposure prophylaxis or be monitored for 21 days after pertussis exposure and treated at the onset of signs and symptoms of pertussis

• The Minnesota Department of Health recently issued guidance on this topic: http://www.health.state.mn.us/divs/idepc/diseases/pertussis/hcp/hcsettingexp.html

Diphtheria and tetanus protection also still important

Chicago Department of Health

WPA Poster Collection Library of Congress, 1936-1941

Meningococcal Disease

Meningococcal disease • Caused by the bacterium N. meningitidis (gram

negative diplococci)

• 150-200 cases/year in California; cases peak in winter

• Even with proper treatment, infection may progress rapidly and result in death; 10-20% survivors have sequelae

• Most cases are caused by five N. meningitidis serogroups: A, B, C, W-135 and Y

• Serogroup B is not contained in the quadrivalent (A, C, Y, W) vaccine; ~1/3 of California cases are serogroup B

• First U.S. vaccine that protects against serogroup B disease licensed in October 2014

Meningococcal vaccine for HCP• Microbiologists routinely exposed to N. meningitidis isolates are

recommended to receive a single dose of quadrivalent meningococcal conjugate vaccine (MenACWY), which protects against A, C, Y and W disease

• A booster dose should be administered every 5 years if exposure is ongoing

• Although MenACWY is licensed for persons 2 months through 55 years of age, it produces a higher antibody response in vaccinated persons and is recommended for persons >56 years of age previously received MenACWY and are recommended for revaccination or for whom multiple doses are anticipated (e.g., asplenic persons or microbiologists)

• It is likely that the newly licensed serogroup B vaccine will be recommended by ACIP for microbiologists in 2015

http://www.cdc.gov/mmwr/preview/mmwrhtml/rr6202a1.htm?s_cid=rr6202a1_e

MCV4 vaccine• Quadrivalent conjugate vaccine, contains

capsular polysaccharide antigens to serogroups A, C, Y and W135 Menactra licensed 2005 Menveo licensed in 2010

• Recommended for all persons aged 11-18 years and high-risk persons 2-55 years (e.g., persons with complement component deficiencies or asplenia, laboratory workers, travelers to African meningitis belt)

• Booster dose recommended at age 16 (or 5 years after prior dose) and for high-risk children

MPSV4 College

Recs

MCV4 licensed

Other persons recommended to receive meningococcal vaccine• People with anatomic or functional asplenia, or persistent

complement component deficiencies are recommended to receive a 2-dose primary series of meningococcal conjugate vaccine (8-12 weeks apart)

• HIV infection is not an indication for routine MenACWY vaccination; however, if vaccinated, they should receive a 2-dose vaccine series

• Those who receive MenACWY and/or remain in a group at increased risk should receive a booster dose every 5 years

• For meningococcal vaccine-naïve persons aged ≥56 years who anticipate requiring a single dose of meningococcal vaccine (e.g., travelers and persons at risk as a result of a community outbreak), quadrivalent meningococcal polysaccaride vaccine (MPSV4) is preferred

CDC recommendations for postexposure prophylaxis (PEP)• PEP is now one dose of ciprofloxicin for most people• People in the following groups who had contact with

the case at any time during the 7 days before illness onset are recommended to receive PEP Household contacts, especially children <2 years of age Child care or preschool contacts Those with direct exposure to index patient's secretions

through kissing or through sharing toothbrushes or eating utensils, or markers of close social contact

Those who performed mouth-to-mouth resuscitation, or had unprotected contact during endotracheal intubation/management (direct exposure to patient’s oral secretions)

Those who frequently slept in same dwelling as index patient

Passengers seated directly next to the index case during airline flights lasting more than 8 hours

What happens in the “real world”• Many more people typically receive PEP than those

recommended by CDC, irrespective of whether they are community or HCP contacts

• Occupationally-acquired infection is rare, but it happens In 2010, a CA police officer and respiratory therapist were

infected via contact with a patient The respiratory therapist assisted with intubation and was not

wearing a mask – he would have been recommended to receive PEP but did not receive it

The unmasked police officer’s only contact with the patient was turning him from his back to his side; persons with such contact would not typically be recommended to receive PEP

• My personal opinion: A rigid interpretation of the recommendations and denial of PEP to HCP who are very concerned about their exposure is probably not warranted

Other resources for occupational health

• Medical center occupational and employee health issues (MCOH-EH) listserv http://mylist.net/listinfo/mcoh-eh

• American College of Occupational and Environmental Medicine http://www.acoem.org

• CDPH measles page http://www.cdph.ca.gov/HealthInfo/discond/Pages/

Measles.aspx

• CDPH meningococcal disease page http://www.cdph.ca.gov/healthinfo/discond/Pages/

MeningococcalDisease.aspx