Infection-control guidelines for health-care workers routinely have included recommendations for immunization against specific diseases for which there is occupational risk. This column summarizes some of the highlights about this preventive strategy. Hepatitis B vaccine is probably the first immunization most health-care workers think of since hepatitis B virus is the most infectious, bloodborne microbial hazard for health professionals. Although there was some hesitancy initially after the original vaccine’s release in 1982, a large percentage of U.S. dentists had completed or begun the three-injection HBV immunization regimen by 1986. In fact, dental professionals were the first health-care group vaccinated against HBV in large numbers. The preparation’s immunological protection, along with implementation of universal (now “standard”) precautions, has assisted in a significant decline in incidence of hepatitis B among health-care workers in the last 20 years.
As the list of vaccine-preventable diseases has expanded, so have recent recommendations for health-care workers with potential infection risks from occupational exposures. Preventing the potential spread of microbial diseases from an infected worker to his or her patients is an important reason for immunization. The major rationale, however, is to protect the primary target of occupational infection - the health professional who provides patient care. Thus, immunization against vaccine-preventable diseases is important in two major respects because it:
1)protects the health-care worker from diseases that can result in serious complications when adult infections occur (e.g., varicella, mumps, rubella) and
2)prevents the health-care worker from serving as a source of cross-infection to patients, especially those who are severely immune-compromised (e.g., cancer, transplant, HIV/AIDS, elderly patients). Often, these patients’ infections present with a substantially higher risk for serious morbidity or even death.
Based on this rationale, the CDC Advisory Committee on Immunization Practices has included specific vaccine recommendations within its broader infection-control guidelines. Thus, it is recommended that health-care workers be immune against mumps, measles, rubella, and varicella. Nosocomial outbreaks in hospitals and other health-care facilities have occurred for each of these viral infections with both patient-to-worker and worker-to-patient transmission reported. With regard to varicella, extensive investigation of adult cases of chicken pox have shown that 1 to 2 percent of adults who develop varicella require hospitalization because of the severity of infection. In addition, health-care workers with the potential for occupational exposure to blood or other potentially infectious materials should be immunized against hepatitis B. Many readers of this column have been beneficiaries of this infection-control strategy since a significant decline in the incidence of HBV infection in dental and medical professionals occurred after the release of the original hepatitis B vaccine. The inclusion of an annual vaccination against influenza recognizes the highly infectious nature of this disease, and the susceptibility of health-care workers who are exposed to the high concentrations of virus present in respiratory aerosols released by persons with “the flu.” Besides the vaccinations necessary to accomplish health-care worker immunity against these diseases, health professionals’ receipt of immunizations that are routinely recommended for adults by the Public Health Service (e.g., tetanus, diphtheria, pneumococcal vaccines) remains an important component of infection control, along with highly effective public health policy.
Recommendations also have been presented regarding vaccination for health-care workers who either are immune-compromised (e.g., congenital immunodeficiency, HIV infection, asplenia, renal failure, diabetes, alcoholic cirrhosis), or who have special conditions, such as pregnancy. Most concerns focus on immune-compromised workers, many of whom may not be candidates for attenuated (live) vaccines. Yet, they still have heightened risk because of their suboptimal immune capabilities.
Health professionals can receive excellent protection from vaccine-preventable diseases that present occupational risks by getting necessary immunizations. Data collected over decades has demonstrated the effectiveness of vaccination on diseases that had high morbidity and mortality rates within the general population just a few generations ago. Vaccination works. The task is to make sure those who need it avail themselves of the opportunity.
Dr. John A. Molinari received a PhD in microbiology from the University of Pittsburgh School of Dental Medicine. He is a professor and chairman of the Department of Biomedical Sciences at the University of Detroit Mercy School of Dentistry. He has published and lectured in the areas of infectious diseases, clinical immunology, and infection control. He also addresses these areas as a consultant to the CDC, ADA Council on Dental Practice, and Council on Scientific Affairs. Contact him at (313) 494-6632, or [email protected].
