Boxes of disposable facemasks greet visitors at US hospitals during winter months. Prominent signs warn visitors to stay away if feeling sick or to don masks for any type of cough. As health care facilities seek to keep potential flu virus carriers outside the hospital, some health care workers believe it’s okay to be on the inside without the protection of an influenza vaccination.

With almost every state reporting extensive flu activity this year, preventing its spread is a top priority. The best defense against the flu is vaccination. Guidelines issued by the Centers for Disease Control and Prevention (CDC) prioritize patient and caregiver groups that should receive the seasonal vaccine annually. For more than 2 decades, the CDC has recommended all health care workers receive annual influenza vaccination. But despite widespread belief that most health care workers seek immunization in large numbers, the CDC estimates 63.5% of health care workers were vaccinated in 2010-2011, with a rate of 98.1% where employers required vaccination. You might ask why someone whose professional duty is to prevent and treat illness would refuse the flu vaccine. The reasons vary from fear of side effects, to previous reactions, lack of confidence in the vaccine’s effectiveness, denying susceptibility to the flu, fear of needles, and claiming poor access to the vaccine. Personal objections are cited on religious grounds, or not wanting to be forced to put something into one’s body, or strict adherence to a vegan diet prohibiting animal products or byproducts.

But what do we really know about transmission of flu from caregiver to patient? The CDC reports that vaccinated health care workers help to reduce transmission of influenza to patients and other staff, thus reducing illness and absenteeism, and influenza-related illness and death. In addition, higher vaccination levels among staff have been associated with lowering the risk of nosocomial influenza cases, thereby lowering the risk of other influenza-related illness or death, particularly in settings like nursing homes. (see http://www.cdc.gov/flu/healthcareworkers.htm)

Some employers have been firing employees who refuse vaccination or do not comply with policies mandating use of protective devices for unvaccinated workers. The firings stem from enforcement of mandatory state vaccine laws. Today, 20 states have laws requiring health care institutions to develop policies about vaccination. Other vaccinations for health care workers have been broadly accepted such as measles, mumps, and hepatitis. None, however, are mandatory without some type of exemption with a signed declination, or temporary removal from the work setting.

The debate about mandatory vaccination for healthcare workers is not new. The American Nurses Association (ANA) has been urging all registered nurses to get the seasonal influenza vaccine, and it has supported aggressive vaccination programs for several years. The ANA believes policies mandating health care workers be vaccinated should be part of a comprehensive infection control program that is broad, fair, and non-discriminatory. Additional elements included in a prevention program are protective equipment (masks) and adherence to hand-washing procedures. Employers should also encourage health care works to stay home when sick.

Despite the best science, the vaccine is not 100% effective. Each year vaccines are engineered to address the strains of flu likely to emerge in the coming season. Efficacy for the 2012-2013 vaccine is estimated at 62%—better than some prior years but still lacking the desired level of potency. In 2007, the Joint Commission made it a requirement for accredited facilities to offer vaccination to employees, removing one of the barriers to lower rates of worker vaccination.

The flu season is waning but has taken its toll with almost forty deaths of children reported through January. There is no counting of adult deaths, but the CDC reported hospitalizations of adults 65 years and older were five times higher this year for laboratory confirmed influenza—that’s at least 50% of the hospitalizations for flu.

Arthur Caplan, a well-known ethicist, has been advocating for mandatory vaccination for several years, believing the protection and best interests of the patient takes priority over an individual health care worker’s choice. I agree. I am not a fan of most things “mandatory” and in this case, believe the fair and reasonable concession is to provide for a declination based on medical contraindication or religious belief. When one chooses to opt out, there are consequences that may range from removal from the work setting for some period of time, use of alternative protective measures, or in some cases where the law is absolute loss of employment. But by offering the choice, the health care worker exercises her/his right to decline and accepts the personal consequences. The goal of vaccination is to achieve the highest possible level of protection for patients. There is ample evidence to mandate vaccination as a measure to “do no harm.”