Why hospitals seek 'herd immunity'

"Herd immunity” occurs when a sufficiently large part of a population is immune to a disease. A large number of immune individuals effectively interrupts the chain of contagion from person to person. This can prevent an epidemic, and it can confer indirect protection against the disease for members of the population who are without individual immunity.

Herd immunity is why hospitals, consistent with advice of the CDC and the Joint Commission, work hard to get flu shots for their physicians, employees, and volunteers. A high level of flu vaccination within the "hospital herd” helps protect vulnerable patients – those who are older, those with multiple conditions, and those with weakened immune systems.

Richard Daines, MD, the New York State Commissioner of Health, says flu shots for physicians and hospital workers are a matter of patient safety:

[T]he failure to adequately immunize HCP (health care personnel) is a patient safety issue….Low vaccination rates among HCP are associated with an increased number of outbreaks, poor patient outcomes, and increased employee absenteeism. Despite this, HCP vaccination rates remain low…

According to the National Foundation for Infectious Diseases, the percentage of health care workers getting flu shots was 42% in 2006. Dr. Daines has set a goal of 60% flu vaccinations for health care workers by 2010.

I’m pleased to observe that 74% of the employees at Community General Hospital received the flu vaccine last year. We're working for an even greater percentage this flu season.

The flu season is upon us, and the Department of Health tracks the flu, county by county. See the state map (above), which is updated weekly. Influenza was confirmed in six New York counties the week of November 1.

In recent weeks the infection control staff has given flu shots all over Community, including on weekends and evenings. Yesterday, nurse leaders conducted a flu clinic for employees and members of their families. My thanks to Employee Health and to Infection Control and Nursing Services for their special efforts to assure herd immunity at Community General this flu season.

Civil liberties v. mandatory flu shots

"I just don't like to have somebody tell me what to put in my body. . . .My biggest concern is my civil liberties."

That, according to The Post-Standard, is the opinion of a registered nurse who works at another Syracuse hospital. The nurse is referring to a new state policy requiring all hospital staff to have the flu vaccine. [1]

The mandate becomes effective November 30, when flu vaccinations are required for anyone working in a hospital ("paid or unpaid") with direct patient care responsibilities. The mandate also includes hospital personnel “whose activities are such that they pose a risk of transmission of influenza to patients or to those who provide direct care to patients.”

In an open letter to health care workers last month, Dr. Richard Daines, New York's health commissioner, said:

[T]he facts are very clear: the welfare of patients is, without any doubt, best served by the very high rates of staff immunity that can only be achieved with mandatory influenza vaccination – not the 40-50% rates of staff immunization historically achieved with even the most vigorous of voluntary programs.

Dr. Daines is referring to the phenomenon of herd immunity, about which I wrote last year. The "herd effect" is typically achieved at high levels of immunity, say, 80% or more. A source of justifiable pride: last year Community's employees achieved an 85% flu vaccination rate on a voluntary basis, possibly the highest number in the state.

What is the responsibility of a hospital employee to take all reasonable precautions to prevent the spread of infection among patients? Are a citizen's individual rights subordinate to the individual's responsibility, when working in a hospital, to minimize health risks for patients?

In the case of the influenza, Dr. Daines is squarely on the side caregiver responsibility: “We as health care workers need to put patients’ interests ahead of our own preferences,” he said, according to The Post-Standard.

A similar thought was expressed last month by a physician at Community's medical executive committee. Following a brief discussion about the state's vaccination requirement, the doctor observed: “The regulation…represents a game change," he said, "in which there is no right for a caregiver to expose a patient to additional risk.”

Flu shots are not the first such mandate for hospital staffs. New York has long required hospital workers to be immunized against measles and rubella as a condition of employment. The state also requires each of us in a hospital to have an annual tuberculosis test.

I am happy to report that, as of last week, 1,092 of Community's employees, physicians and volunteers have been vaccinated against the seasonal flu. More flu clinics for hospital staff are scheduled, as we willingly comply with the state's patient safety requirement.

My thanks, especially, to hospital volunteers, who are covered by the regulation, as they roll up their sleeves for the good of patients.

- - -

[1] In a letter dated August 26, 2009, the State Department of Health cited an “emergency regulation” of August 13, requiring vaccinations of all hospital personnel. The regulation applies to both seasonal flu and the H1N1 (swine) flu vaccines.