EHS tackles impediments to influenza immunization

Fear of adverse reactions influenced decisions

By Judith M. Hearthway, RN, MSN, FNP

Former Employee Health Coordinator

Peninsula Regional Medical Center

Salisbury, MD

Some diseases provoke dread and fear, while others are considered relatively benign. AIDS, cancer, and Alzheimer’s are in the first category, while influenza generally is considered a temporary misery ascribed to the second category. However, "influenza consistently ranks among the top 10 causes of death in the United States."1 By comparison, AIDS-related deaths in the United States in 1995 numbered 45,765,2 while in 1957 the "Asian flu" epidemic killed 60,000 U.S. residents.3

Today, a vaccine that is 70% effective against influenza is available, yet less than 37% of health care workers comply with the Centers for Disease Control and Prevention’s Advisory Committee on Immunization Practices’ (ACIP) recommendations that workers who care for high-risk patients be vaccinated.4

At Peninsula Regional Medical Center in Salisbury, MD, only 12% of more than 2,000 employees were vaccinated in 1991. The employee health service undertook to improve compliance rates. Educational messages about the disease, vaccine effectiveness and availability, and ACIP recommendations were distributed through the hospital newsletter, in-house TV, posters, paycheck envelopes, and employee cafeteria tables.

Clinical managers more actively advocated participation in their areas when they realized that absenteeism resulting from illness made scheduling more difficult for everyone. A prominent pulmonologist strongly encouraged physicians and employees be vaccinated to protect his vulnerable patients who were at risk of dying. In fact, the thrust of the flu vaccine campaign was to appeal to employees’ altruism by saying, "It is unlikely you will die from the flu. But please get vaccinated to protect your babies, your parents, your patients, and yourself."5

After employees became better informed about flu vaccine, their participation was enhanced by bringing the vaccine to them. For two weeks in October, the EHS kept each clinical area stocked with vaccine, consent forms, and supplies so employees could be vaccinated whenever they chose. In most cases, the clinical managers gave the injections or delegated the function to willing staff members. Subtle peer pressure, more information, and improved accessibility dramatically improved participation rates to 42% in 1995.

However, interviews with employees who still refused immunization revealed that the fear of adverse reactions influenced their decisions. Many had heard about or experienced reactions to past vaccines, notably the 1976 "swine flu" vaccine. Explaining that the vaccine now in use is derived from subunits of chemically killed viruses that cannot cause influenza disease was not enough to assuage employees’ concerns about adverse reactions. This motivated an in-house study to determine what reactions were associated with current flu vaccine.

Review of literature revealed universal acknowledgment that a sore arm is a common effect of flu vaccination.6,7 On the other hand, injection of placebo also has resulted in arm soreness in 35% to 44% of recipients,8 suggesting that local soreness may result any time a steel needle is stuck into one’s muscle.

Authors rarely include respiratory symptoms as vaccination side effects. Indeed, one study states unequivocally, "Respiratory disease after vaccination represents coincidental illness unrelated to influenza vaccination."9 Most noteworthy are two other studies concluding that influenza vaccination causes no more systemic reactions than placebo injections among the elderly.10,11 Somewhat greater reactivity has been reported among young vaccinees who have less immune system experience with flu disease or vaccine, and who mount a generally greater immune response than older recipients.12

These results were replicated in a study of employees of Peninsula Regional Medical Center in October 1996.13 An employee health nurse explained the study and gave the vaccine to the 72 participants. For a 72-hour period immediately after vaccination, employees completed one of two questionnaire formats: a subjective diary of perceived symptoms, or an objective check-off of 13 symptoms. During the same interval, identical questionnaires were distributed to employees who had not been vaccinated. Forms were returned by 57 vaccinated and 15 non-vaccinated employees; median ages were 46 and 37, respectively. There was no difference in reported symptoms between the two questionnaire formats (t=-.66). The table (see p. 118) summarizes the most noteworthy local and systemic symptoms reported.

A t-test revealed no significant difference in the two groups’ reports of aggregate systemic reactions (p=.058). Despite the intrinsic difficulty in comparing two groups of unequal sizes, it can be clearly seen that the non-vaccinated group reported symptoms at least as frequently as the vaccinated subjects.

In future influenza vaccination programs at Peninsula Regional, the EHS plans to give employees the following information:

• Expect minor soreness at the injection site.

• Systemic symptoms as reported by co-workers in 1996 may occur infrequently, but the occurrence rate among vaccinated persons is not greater than among unvaccinated persons.

• Younger recipients may be more likely to have some reaction that diminishes with subsequent annual vaccinations as the immune system recognizes the antigen.


1. White D. Influenza vaccination: Is it worth it? Australian Family Physician 1991; 20:543-552.

2. Centers for Disease Control and Prevention. HIV/AIDS Surveillance Report 1996; 8(no. 2):1-39.

3. Baum SG. Influenza: A serious epidemic disease that can be prevented. Mount Sinai J Med 1990; 57:225-235.

4. Nafziger DA, Herwaldt LA. Attitudes of internal medicine residents regarding influenza vaccination. Infect Control Hosp Epidemiol 1994; 15: 32-35.

5. Personal communication, 1996.

6. Al-Mazrou A, Scheifele DW, Soong T, et al. Comparison of adverse reactions to whole-virion and split-virion influ enza vaccines in hospital personnel. Canadian Med Assoc J 1991; 149:213-218.

7. Langlois PH, Smolensky MH, Glezen WP, et al. Diurnal variation in responses to influenza vaccine. Chronobiology International 1995; 12:28-36.

8. Scheifele DW, Bjornson G, Johnston J. Evaluation of adverse effects after influenza vaccination in hospital personnel. Canadian Med Assoc J 1990; 142:127-130.

9. Glathe H, Lange W. Influenza vaccine in older patients. Drugs and Aging 1995; 6:368-387.

10. Margolis KL, Nichol KL, Poland GA, et al. Frequency of adverse reactions to influenza vaccine in the elderly. JAMA 1990; 264:1139-1141.

11. Govaert TE, Dinant GJ, Aretz K, et al. Adverse reactions to influenza vaccine in elderly people: Randomized double-blind placebo-controlled trial. Br Med J 1993; 301:988-990.

12. Palache AM, Beyer WP, Sprenger MW, et al. Antibody response after influenza immunization with various vaccine doses: A double-blind, placebo-controlled, multi-centre, dose-response study in elderly nursing-home residents and young volunteers. Vaccine 1993; 11:3-9.

13. Hearthway JM. Adverse Reactions Associated with Influenza Vaccine. Unpublished manuscript. Salisbury, MD: Salisbury State University; 1997.