ACCIDENTAL EXPOSURE PROGRAM FOR BLOOD-BORNE PATHOGENS

Alan Winkelstein, M.D., Medical Director

INTRODUCTION

Every health-care institution has a moral, ethical, and legal obligation to provide an effective program protecting its employees against accidental exposure to blood borne pathogens.  As of January 1, 1992, OSHA requires that “all healthcare providers have a documented plan for handling these incidents.”  In addition, PA Act 148 specifies that all healthcare facilities have a mechanism for certifying exposure to HIV and to provide workers with counseling and testing.  Mechanisms have been established for testing the source of the exposure.  Of importance, no physician can certify an exposure for his/her employee.

Central Blood Bank (CBB) has developed a comprehensive program to provide health-care workers with complete accidental exposure services and to fulfill all legal requirements.  This program, which represents an extension of that used for its own employees, includes vaccinations for hepatitis B and for individuals exposed to blood borne pathogens (hepatitis B, hepatitis C, HIV, and HTLV-I/II), a complete array of services including pre- and post-test counseling, serial testing and where appropriate, prophylactic treatment.  This service is available 24 hours per day, seven days per week.

Probably the most significant risk in an accidental exposure is the possibility of infection with hepatitis B.  It has been estimated that 12-18,000 health-care workers are infected annually and that at least 300 of these individuals will ultimately die of the complications of hepatitis B infection.  These include chronic active hepatitis, cirrhosis, and hepatocellular carcinoma.  There is a large pool of hepatitis B carriers; at least one million individuals are infectious.  Many are asymptomatic.

Hepatitis B vaccination is both safe and effective.  Post-vaccination antibody testing is not recommended unless the health-care worker is at significant risk of parenteral exposure.  OSHA requires that all health-care facilities offer hepatitis B vaccination to all employees, free of charge, and each must document either acceptance or refusal.

If an exposed health-care worker has not been vaccinated, he/she should receive the hepatitis B immune globulin (HBIG).  Although there is some efficacy of this globulin as late as seven days after exposure, it is recommended that it be given within 72 hours.  At the same time, the worker should begin immunization; this will not protect him/her from the current exposure but will provide long-term protective immunity in the future.  The health-care worker should be monitored with serial hepatitis B serology.

A considerable fear of the health-care worker is HIV infection as a result of the accidental exposure.  In fact, HIV is relatively difficult to transmit from an infected patient to a health-care worker as a result of an accidental exposure reported to the CDC; three have developed AIDS and one has died.  It has been estimated that the rate of infections from contaminated needle sticks is less than 4/1,000.  Thus, the risk of HIV is several orders of magnitude less than hepatitis B.

Nevertheless, a health-care worker who is exposed to blood or infectious body fluids requires complete and compassionate counseling and confidential testing.  If the baseline testing of the health –care worker is negative and the serostatus of the source is not known, PA Act 148 provides for source testing.  In case of a high risk exposure, the health-care worker should be given the option of taking Zidovudine (AZT), the antiviral drug used to treat HIV infections.  There is clinical data indicating that it can prevent infections.  However, animal experiments with retroviral infections have shown that this drug will modify or prevent infections if given shortly after exposure.  It is offered by many medical centers that treat large numbers of HIV infected patients.  The CDC reviewed the evidence concerning AZT prophylaxis and declined to either recommend or discourage its use.  If a health-care worker who incurs a high-risk accidental exposure wishes to take AZT, it is recommended that therapy be started as soon as possible after the exposure.  Usually within hours.

Like HIV and hepatitis B, hepatitis C virus can be transmitted by parenteral exposure to health-care workers.  This virus is the most common cause of parenterally transmitted non-A, non-B hepatitis; like hepatitis B, infections with hepatitis C can result in chronic active hepatitis, cirrhosis, and an increased risk of hepatocellular carcinoma.  Immune serum globulin should be administered to a health-care worker potentially exposed to this virus; it will provide at least partial protection.

Health-care facilities can enroll in Central Blood Bank’s Accidental Exposure Program; this comprehensive program fulfills all legal requirements.  Hepatitis B vaccinations are available.  In addition, an experienced nurse counselor is on call 24 hours/day, seven days/week to handle any accidental exposure incidents.  All exposures are discussed with the Central Blood Bank physician on-call.  A health-care worker who incurs a significant exposure will be seen within 12-18 hours of the injury. 

Copies of the Transfusion Medicine Update can be obtained by contacting Deborah Small at (412) 209-7320 or
by e-mail:  dsmall@itxm.org.