Bloodborne Diseases

Common Bloodborne Diseases

Hepatitis B is caused by infection with the hepatitis B virus (HBV). In about 30% of cases, the person experiences no symptoms; others may experience jaundice, fatigue, abdominal pain, loss of appetite, nausea, vomiting, and joint pain. Infection may become chronic, particularly to infants infected at birth, and may lead to death from chronic liver disease (15% to 25% of all cases). A hepatitis B vaccine has been available since 1982 and is recommended for people in high-risk groups, including health workers, household members and sexual partners of persons infected with HBV, injection drug users, and persons traveling to or living in parts of the world where HBV infection is endemic. According to the Centers for Disease Control and Prevention (CDC), about 300,000 cases of HBV occur in the United States annually.

Hepatitis C is caused by infection with the hepatitis C virus (HCV). Persons at highest risk include injection drug users, persons treated for blood-clotting problems before 1987 or who received a blood transfusion before 1992, and hemodialysis patients. Eighty percent of individuals infected with HCV have no symptoms, but hepatitis C causes liver damage and is a leading indicator for liver transplants. About 70% of infected individuals develop chronic liver disease and 5% to 20% will develop cirrhosis. There is no vaccine for hepatitis C but several drug treatments are available. According to the CDC, about 26,000 new cases of HCV were identified in the United States in 2004, and 4.1 million people are living with the disease.

HIV (human immunodeficiency virus) is a virus transmitted primarily through blood; typical routes of infection include unprotected sexual activity and use of unsterilized needles (and outside the industrialized world, use of other unsterilized sharps and transfusion of contaminated blood). Acquired immunodeficiency syndrome (AIDS) is a label given to the advanced stages of HIV infection, when the person's immune system starts failing and he or she is subject to many opportunistic infections as well as [Page 101]unusual cancers such as Kaposi's sarcoma. There is no vaccine for AIDS but a number of medical treatments are available. The CDC estimates that there are approximately 44,000 new infections annually; approximately 1.1 million people in the United States were living with HIV/AIDS in 2003.

Viral hemorrhagic fevers (VHFs) are a group of illnesses caused by bloodborne viruses, which damage the vascular system and cause hemorrhage (bleeding). Most VHFs are zoonotic, with rodents and arthropods the main reservoirs; however, the hosts of Ebola and Marburg viruses, two of the best-known VHFs, are unknown. Symptoms of infection with a VHF include fever, fatigue, dizziness, muscle aches, loss of strength, exhaustion, and bleeding under the skin, in internal organs, and from body orifices. There are no vaccines for VHFs and treatment is primarily supportive. Prevention of VHF infection is based on preventing contact with host species, for example, controlling rodent populations, keeping them out of homes and workplaces, and cleaning up rodent nests and droppings. VHFs can be spread through physical contact, so isolation of infected individuals is recommended, with Universal Precautions (defined below) observed by health care workers treating VHF patients.

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