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Health Officer Influenza Vaccination and Masking Order FAQ

Why is the influenza vaccination and masking order needed?

Influenza vaccination protects health care workers (HCWs) and patients. Influenza is a serious disease that can cause severe illness, hospitalization, and death in people of all ages. The most effective method of preventing influenza infection is through vaccination. HCWs are at increased risk of exposure to influenza from ill patients. Infected HCWs can transmit influenza to patients and coworkers before they are symptomatic.

Which facilities are affected by the influenza vaccination and masking order?

We encourage everyone over six months of age to get influenza vaccine each year. The vaccination and masking order applies to all licensed health care facilities in Contra Costa County, including:

Acute psychiatric hospital
Adult day health center
Alternative birthing center
Chemical dependency recovery hospital
Chronic dialysis clinic
Community clinic or free clinic
Congregate living health facility
Correctional treatment center
District hospital with <100 beds
Emergency Medical Service Providers
General acute care hospital
Home health agency
Intermediate care facility

Intermediate care facility - developmentally disabled
Intermediate care facility - developmentally disabled - habilitative
Intermediate care facility - developmentally disabled - nursing
Pediatric day health respite care
Psychology clinic
Referral agency
Rehabilitation clinic
Skilled nursing facility
Special hospital
Surgical clinic

This list is from the Licensing and Certification Division, California Department of Public Health, which licenses California health care facilities (

Who is considered a health care worker?

For the purposes of this order, a health care worker is defined as a person, paid or unpaid, working in licensed care settings who has direct patient contact or who works in patient care areas. A person working for a licensed home health agency or hospice who works in patient homes would be considered a health care worker with direct patient contact.

For facilities needing more guidance or clarification, we use the CDC National Healthcare Safety Network's (NHSN) definition of a health care worker: a person who works in the facility, whether paid or unpaid, who has the potential for exposure to infectious materials, including body substances, contaminated medical supplies and equipment, contaminated environmental surfaces, or contaminated air. Health care workers can 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 healthcare 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 a health care worker. It includes students, trainees, and volunteers.

When is influenza season?

Influenza season is defined as the period of November 1 to March 31 of the following year. The Health Officer may extend the mandatory masking period if surveillance data demonstrate an unusually late peak and continued widespread influenza activity in the spring. HCWs should be offered influenza vaccine before influenza season as it can take up to two weeks to develop protection.

What kind of mask should be used? When should masks be changed, replaced, or discarded?

Please check with your facility about details of the implementation of this order including specifications of type of mask.

How is this order different from an influenza vaccination declination policy?

State law currently requires that certain health care facilities offer influenza vaccination to employees. Employees that decline vaccination are only required to sign a declination statement. While compliance with this policy is high, influenza vaccination rates are not. Mandatory influenza vaccination or masking policies have increased HCW vaccination rates to greater than 95%. Influenza vaccination helps keep HCWs and patients healthy.

Can HCWs decline influenza vaccination based on a religious or medical exemption?

Health care workers that decline influenza vaccine must wear a mask during influenza season while working in patient care areas.

What about HCWs who have egg allergy?

Allergy to eggs should be distinguished from allergy to influenza vaccine. Please refer to the September 20, 2013 issue of the Morbidity and Mortality Weekly Report (MMWR) for more information about influenza vaccine and egg allergy ( HCWs with a history of mild egg allergy (only hives following egg exposure) can receive the flu shot safely with additional safety precautions as described in the MMWR. The recombinant influenza vaccine (trade name FluBlok) is manufactured without the use of eggs and can be given to HCWs 18 through 49 years of age who have egg allergy of any severity and do not have other contraindications. Vaccination should not be delayed if recombinant influenza vaccine is not available. A cell culture derived influenza vaccine (trade name Flucelvax) contains much less egg protein than traditional egg-based influenza vaccine. Cell culture influenza vaccine is licensed for use in adults 18 years and older. Due to limited data on the safety of nasal spray and egg allergy, HCWs with egg allergy should receive the shot rather than the spray. If a HCW cannot receive influenza vaccine due to a medical condition, then they must wear a mask during influenza season while working in patient care areas.

Should a HCW who is immunocompromised or has a chronic health condition (asthma, diabetes, etc.) receive influenza vaccine?

HCWs in these groups can benefit from influenza vaccination as they are at greater risk of severe influenza illness and complications.

Should a HCW who is pregnant receive influenza vaccine?

The influenza shot can and should be given to pregnant women during any trimester. Pregnant women and their newborn can benefit from influenza vaccination as both are at greater risk of severe influenza illness and complications. Women who receive influenza vaccine during pregnancy can pass protection to their newborn. This is important because children under six months of age are too young to be vaccinated for influenza. By California law, pregnant women should receive preservative-free influenza vaccine available as prefilled syringes and single dose vials.

What kind of flu vaccine can HCWs receive?

There are multiple flu vaccines available with varying age indications. When more than one product is appropriate for a HCW, the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices (ACIP) expresses no preference for any given flu vaccine over another. The intradermal shot is indicated for persons 18 through 49 years of age. The high-dose shot is indicated for persons 65 years of age and older. Nasal spray vaccine is licensed for use in healthy, non-pregnant persons 2 through 49 years of age. ACIP indicates no preference for nasal spray versus shot in this age group. HCWs who care for severely immunosuppressed patients who require a protective environment (e.g. bone marrow transplant unit) should receive the shot instead of the nasal spray. The Vaccine Information Statement for the flu shot and nasal spray vaccine are available here:

Is there a preference for trivalent or quadrivalent flu vaccine?

Historically, flu vaccine contains three strains (trivalent), two influenza A strains and one B strain. For the 2013-2014 influenza season, a limited amount of influenza vaccine will contain four flu strains (quadrivalent). Quadrivalent vaccine contains the same two A strains and one B strain as the trivalent vaccine with the addition of another B strain. When more than one product is appropriate for a HCW, the ACIP expresses no preference for any given flu vaccine over another. Vaccination should not be delayed if only trivalent vaccine is available.

Which takes precedence, Contra Costa County’s Health Officer order or state laws regarding influenza and HCWs?

This Health Officer order is in addition to any State laws regarding influenza and HCWs. California Health and Safety code §120175 authorizes Health Officers to control contagious, infectious, or communicable disease and may “take measures as may be necessary” to prevent and control the spread of disease within their jurisdiction. Facilities must comply with the Health Officer order as well as the applicable State laws regarding influenza vaccine and HCWs. For instance, as specified under State law, acute care hospitals in Contra Costa will still be required to report their HCW influenza vaccination rate to the California Department of Public Health, and they will also be required to implement this order.

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