Bloodborne Pathogens ENVH 451/541 November 12, 2008

Bloodborne Pathogens (BBPs) O ther P otentially I nfectious M aterials Present in Blood or

Bloodborne Pathogens semen vaginal secretions body fluids such as pleural, cerebrospinal, pericardial, peritoneal, synovial, and amniotic saliva in dental procedures (if blood is present) any body fluids visibly contaminated with blood body fluid where it is difficult to differentiate any unfixed tissue or organ (other than intact skin) from a human (living or dead) HIV- or HBV- containing cultures (cell, tissue, or organ), culture medium, or other solutions blood, organs, & tissues from animals infected with HIV, HBV, or BBPs OPIM

2 Methods of Entry: Mucocutaneous –Enters through mucus membranes Percutaneous –Enters through some opening of the skin

) Mucocutaneous ( through a mucous membrane ) Having infected blood or other body fluids splashed into eyes, nose or mouth Modes of Transmission

Percutaneous (through the skin) Being stuck with needles or other sharps Having infected blood or other body fluids splashed onto skin that is cut, scratched, has sores or rashes or other skin conditions Modes of Transmission

Bloodborne Pathogen Diseases Some examples of bloodborne pathogens: Malaria Syphilis Brucellosis Leptospirosis Arboviral infections Relapsing fever Creutzfeld-Jakob Disease Viral Hemorrhagic Fever Ebola, Marburg Primary Pathogens of Concern: Hepatitis B Virus (HBV) Hepatitis C Virus (HCV) Human Immunodeficiency Virus (HIV)

HIV

A global view of HIV infection 33 million people [30–36 million] living with HIV, 2007

HIV/AIDS in King County HIV - 2,773 AIDS - 3,532 HIV/AIDS - 6,305

HIV and AIDS The CDC defines AIDS as a positive HIV test and one of the following: The development of an opportunistic infection – an infection that occurs when your immune system is impaired A CD4 lymphocyte count of 200 or less –a normal count ranges from 800 to 1,200 – directly attack and kill invading cells

Natural History of Infection

Symptoms Immediately following infection –Nonspecific “viral illness” Low grade fever, rash, muscle aches, headache, fatigue Resolve in 5-10 days Asymptomatic –Immune system is cycling with CD4 cells AIDS –Extreme fatigue, rapid weight loss, swollen lymph nodes, dry cough and shortness of breath, night sweats

Management No “cure” HAART –“cocktail” of 3 -4 AR drugs –Difficult: complex regimes, severe side effects, compliance very important Diarrhea, vomiting, nausea, headache, blurred vision, dizziness, congestion, dry mouth, fatique, body ache, fever, rash, sores, feeling loss, difficulty sleeping, changing body shape, hair loss, dry skin, etc.

HIV IN BLOOD SURVIVAL OUTSIDE THE BODY –In dry blood the virus can survive for up to 6 days in laboratory conditions QUANTITY OF VIRUS IN BLOOD –1 mL of blood contains ,000 particles of virus. RISK OF INFECTION FOLLOWING NEEDLE STICK INJURY –Low - 0.3% - 3 people in 1,000. RISK OF INFECTION FOLLOWING EYE SPLASH –Low % * Updated U.S. Public Health Service Guidelines for the Management of Occupational Exposures to HBV, HCV, and HIV and Recommendations for Postexposure Prophylaxis. MMWR Recommendations and Reports, June 29, 2001 / 50(RRll);1-42. Centers for Disease Control and Prevention

Hepatitis C

Global Burden of HCV

Hepatitis C Symptoms flu-like symptoms jaundice fatigue dark urine abdominal pain loss of appetite nausea

US HCV Infection Incubation periodAverage 6-7 weeks Range 2-26 weeks Acute illness (jaundice)Mild (<20%) Case fatality rateLow 8-10 K Chronic infection60%-85% 2.7M people Chronic hepatitis10%-70% Cirrhosis<5%-20% Mortality from CLD1%-5%

Source: Sentinel Counties, CDC Sources of Infection for Persons With Hepatitis C Sexual 15% Other 1%* Unknown 10% Injecting drug use 60% Transfusion 10% (before screening) * Nosocomial; iatrogenic; perinatal Occupational 4%

Occupational Transmission Inefficient by occupational exposures Incidence 1.8% following needle stick from HCV-positive source –Associated with hollow-bore needles Prevalence 1-2% among health care workers –Lower than adults in the general population –Most appear related to HCW substance abuse –No restrictions routinely recommended for HCV- infected HCWs

Perinatal Transmission of HCV Transmission only from women HCV-RNA positive at delivery –Average rate of infection 6% –Higher (17%) if woman co-infected with HIV –Role of viral titer unclear No association with –Delivery method –Breastfeeding Infected infants do well –Severe hepatitis is rare

HEPATITIS C IN BLOOD SURVIVAL OUTSIDE THE BODY –Little is known but likely to be the same as hepatitis B, up to 10 days QUANTITY OF VIRUS IN BLOOD –1 mL of blood contains 1, ,000 particles of virus RISK OF INFECTION FOLLOWING NEEDLE STICK INJURY –Medium - 3% - 3 people in 100 RISK OF INFECTION FOLLOWING EYE SPLASH –Low * Updated U.S. Public Health Service Guidelines for the Management of Occupational Exposures to HBV, HCV, and HIV and Recommendations for Postexposure Prophylaxis. MMWR Recommendations and Reports, June 29, 2001 / 50(RRll);1-42. Centers for Disease Control and Prevention

Hepatitis B

Symptoms flu-like symptoms fatigue abdominal pain loss of appetite nausea, vomiting joint pain jaundice Incubation days following infection Duration Several weeks to months

Global Distribution of HBV  8% - High

Global Patterns of Chronic HBV Infection High ( > 8%): 45% of global population – lifetime risk of infection >60% – early childhood infections common Intermediate (2%-7%): 43% of global population – lifetime risk of infection 20%-60% – infections occur in all age groups Low (<2%): 12% of global population – lifetime risk of infection <20% – most infections occur in adult risk groups

Hepatitis B Incidence

Risk Factors Associated with Reported Hepatitis B, , United States Source: NNDSS/VHSP *Other: Surgery, dental surgery, acupuncture, tattoo, other percutaneous injury

Transmission of HBV Concentration of HBV in various body fluids –High: Blood, serum, wound exudates –Medium: saliva, semen, and vaginal secretions –Low/not detectable: urine, feces, sweat, tears, breastmilk Household transmission – less risk than percutaneous but significant - can occur in settings such as shared toothbrushes, razors, combs, washcloths

Transmission of HBV Likelihood of becoming a carrier varies inversely with the age at which infection occurs. Pool of carriers in U.S. is million persons. ~5000 persons die/yr. from HBV-related cirrhosis.

Prevention & Treatment “Advisory Committee on Immunization Practices (ACIP) recommends that all children receive their first dose of hepatitis B vaccine at birth and complete the vaccine series by age 6–18 months” (CDC) –Adults where deficient Acute Infection –no medication is available; treatment is supportive Chronic Infection –several antiviral drug –require regular monitoring to determine whether disease is progressing and to identify liver damage or hepatocellular carcinoma.

HEPATITIS B IN BLOOD SURVIVAL OUTSIDE THE BODY –In dry blood the virus can survive for up to 10 days QUANTITY OF VIRUS IN BLOOD –1 mL of blood contains 100,000,000 particles of virus RISK OF INFECTION FOLLOWING NEEDLE STICK INJURY –Very High - 30% - 3 people in 10 RISK OF INFECTION FOLLOWING EYE SPLASH –High. * Updated U.S. Public Health Service Guidelines for the Management of Occupational Exposures to HBV, HCV, and HIV and Recommendations for Postexposure Prophylaxis. MMWR Recommendations and Reports, June 29, 2001 / 50(RRll);1-42. Centers for Disease Control and Prevention

Occupational Exposure

means reasonably anticipated skin, eye, mucous membrane, or parenteral (piercing of the skin) contact with blood or OPIM that may result from the performance of an employee's duties Occupational Exposure Transmission of BBPs is a specific contact with blood or OPIM that is capable of transmitting a bloodborne disease Exposure Incident

Most Common Occupational Exposure Needlestick Injuries Over 85% of documented occupational transmissions

Health Care Workers and Bloodborne Pathogens HBV: 6%-30% HCV: 1.8% (range 0%-7%) HIV: 0.3% Occupational Transmission Risk of infection following needlestick/cut from a positive (infected) source:

Transmission of BBPs Risk of infection depends on several factors:  The pathogen involved  The type/route of exposure  The amount of virus in the infected blood at the time of exposure  The amount of infected blood involved in the exposure  Whether post-exposure treatment was taken  Specific immune response of the infected individual Courtesy of Owen Mumford, Inc.

Health Care Workers and BBPs Most common: needlesticks Cuts from other contaminated sharps (scalpels, broken glass, etc.) Contact of mucous membranes (eye, nose, mouth) or broken (cut or abraded) skin with contaminated blood Occupational Transmission Causes of percutaneous injuries with hollow- bore needles, by % total percutaneous injuries Manipulating needle in patients 27% IV line- related causes 8% Handling or passing device during or after use 10% Recapping 5% Clean-up 11% Collision w/health care worker or sharp 8% Disposal- related causes 12% Improperly disposed sharp 10% Handling/transferring specimens 5% Other 4% Source: CDC [1999]

Exposure Controls Universal precautions (or equivalent system*) Equipment and Safer Medical Devices Work practices Personal protective equipment Housekeeping Laundry handling Hazard communication - labeling Regulated Waste

Occupational Exposure Protection

Exposure Controls Protected position Unprotected position

Universal Precautions A system of infection control in which all human blood and OPIM are treated as if known to be infectious with a bloodborne disease.