HEPATITIS B

Caused by the hepatitis B virus (HBV), Serum hepatitis as it is sometimes called may be clinically recognized; less than10% of children and 30-50% of adults with acute hepatitis B virus will present with jaundice. The onset is usually insidious with appetite, vague abdominal discomfort, nausea and vomiting, sometimes arthralgia and rash, often progressing to jaundice. Chronic HBV infection is found in 0.5% of adults in North America, and 0.1-20% of people from other parts of the world. After acute HBV infection the risk of developing chronic infection occurs among 90% of infants infected at birth, 20-50% of children infected at 1-5 years of age, and about 1-10% infected as older children or adults.

Where are they found?

Humans. Chimpanzees are susceptible but an animal reservoir in nature has not been recognized. Closely related viruses to HBV have been found in woodchucks, ducks and other animals, but none cause disease in humans.

How do we get infections?

HBV is found in body substances including blood, and blood by products, saliva, spinal fluid, peritoneal, pleural, pericardial, synovial and amniotic fluids; semen, vaginal secretions and other body fluid containing blood; unfixed tissues and organs. Transmission occurs by percutaneous and permucosal exposure. Because HBV is stable in the environment for at least 7 days, indirect inoculation can also occur via inanimate objects. Fecal-oral or vector borne transmission has NOT been demonstrated.

Incubation period

Usually 45-180 days, on average, 60-90 days.

Treatment

Report to local health authority.

Immunization of contacts to include HBIG and hepatitis B vaccine. HBIG should be administered as soon as possible after exposure.

Prevention

"Concurrent disinfection of equipment contaminated with blood or other potentially infectious material using an EPA approved disinfectant that is used according to the manufacturer's recommendation. Universal Precautions should always be observed to prevent exposure to blood and other potentially infectious materials (OPIM). Consult 29CFR.1910.1030 - OSHA Bloodborne Pathogens Standard.