What are bloodborne pathogens?

Bloodborne pathogens are infectious microorganisms in human blood that can cause disease in humans. These pathogens include, but are not limited to, hepatitis B (HBV), hepatitis C (HCV) and human immunodeficiency virus (HIV). Needlesticks and other sharps-related injuries may expose workers to bloodborne pathogens. Workers in many occupations, including first responders, housekeeping personnel in some industries, nurses and other healthcare personnel, all may be at risk for exposure to bloodborne pathogens.


Who is most at risk of exposure 

Exposures to blood and other body fluids occur across a wide variety of occupations. Emergency response, Public Safety personnel and Healthcare workers working in a hospital, clinic, Emergency Care facility and other clinical settings, as well as care and nursing homes, are most vulnerable to occupational exposure to bloodborne pathogens through needlestick and other sharps injuries, mucous membrane, and skin exposures. Often the risk is from needlesticks and other sharps injuries.

Sharps injuries are a serious problem but are often preventable. The Centers for Disease Control and Prevention (CDC) estimates that each year 385,000 needlesticks and other sharps-related injuries are sustained by hospital-based healthcare personnel.

The Bloodborne pathogens most likely to get transmitted

The pathogens of primary concern are:

  • Hepatitis B virus (HBV)

  • Hepatitis C virus (HCV) and

  • Human Immunodeficiency Virus (HIV) 

but the potential exists to be exposed to the transmission of more than 20 other pathogens.

Bloodborne Pathogens

Hepatitis B virus (HBV)

Hepatitis B is a liver infection caused by the Hepatitis B virus (HBV). Hepatitis B is transmitted when:

  • Blood 

  • Semen, or

  • Another body fluid

from a person infected with the Hepatitis B virus enters the body of someone who is not infected.

This can happen through:

  • Sexual contact

  • Sharing needles, syringes, or other drug-injection equipment 

  • From mother to baby at birth or

  • Through needlestick  injury

For some people, Hepatitis B is an acute, or short-term, illness but for others, it can become a long-term, chronic infection.

The risk for chronic infection is related to age at infection approximately 90% of infected infants become chronically infected, compared with 2%–6% of adults.

Chronic Hepatitis B can lead to serious health issues, like cirrhosis or liver cancer.

The best way to prevent Hepatitis B is by getting vaccinated. Healthcare professionals if not already vaccinated have the option to require their employer to provide them with vaccination.


Hepatitis C virus (HCV)

Hepatitis C is a blood-borne virus (HCV) that infects the liver.

HCV is transmitted primarily through parenteral (not via the digestive tract) exposures to infectious blood or body fluids that contain blood. Possible exposures include:

  • Needlestick injuries in health care settings

  • Injection drug use (currently the most common means of HCV transmission in the United States)

  • Receipt of donated blood, blood products, and organs (once a common means of transmission but now rare in the United States since blood screening became available in 1992)

  • Birth to an HCV-infected mother


Although infrequent, HCV can also be spread through:

  • Sex with an HCV-infected person (an inefficient means of transmission, although HIV-infected men who have sex with men [MSM] have increased risk of sexual transmission)

  • Sharing personal items contaminated with infectious blood, such as razors or toothbrushes (also inefficient vectors of transmission)

  • Other health care procedures that involve invasive procedures, such as injections (usually recognized in the context of outbreaks)

  • Unregulated tattooing


70%–85% of people who become infected with HCV, develop a long-term, chronic infection. Chronic Hepatitis C is a serious disease that can result in long-term health problems, even death. The majority of infected persons might not be aware of their infection because they are not clinically ill. There is no vaccine for Hepatitis C. The best way to prevent Hepatitis C is by avoid getting infected.

70%–85% of people who become infected with HCV, develop a long-term, chronic infection. Chronic Hepatitis C is a serious disease that can result in long-term health problems, even death. The majority of infected persons might not be aware of their infection because they are not clinically ill. There is no vaccine for Hepatitis C. The best way to prevent Hepatitis C is to avoid getting infected.

Can HCV be spread during medical or dental procedures?

As long as Standard Precautions and other infection control practices are used consistently, medical and dental procedures performed in the United States generally do not pose a risk for the spread of HCV. However, HCV is spread in health care settings when injection equipment, such as syringes, is shared between patients or when injectable medications or intravenous solutions are mishandled and become contaminated with blood. Health care personnel should understand and adhere to Standard Precautions, which includes Injection Safety practices aimed at reducing bloodborne pathogen risks for patients and health care personnel. If healthcare-associated HCV infection is suspected, this should be reported to state and local public health authorities.

Acute or Chronic HCV

HCV infections can be either:

  • Acute - an illness of short duration, rapidly progressive, and in need of urgent care, or

  • Chronic - an illness that lasts a long time, typically 3 or more months.

How many new HCV infections occur annually in the United States?

In 2016, a total of 2,967 cases of acute hepatitis C were reported to CDC from 42 states. The overall incidence rate for 2016 was 1.0 cases per 100,000 population, an increase from 2015 (0.8 cases per 100,000 population). Actual acute cases are estimated to be 13.9 times the number of reported cases in any year. After adjusting for under-ascertainment and under-reporting, an estimated 41,200 acute hepatitis C cases occurred in 2016.

What is the prevalence of chronic HCV infection in the United States?

An estimated 2.4 million people in the United States are living with hepatitis C  virus infection

Is it possible for someone to become infected with HCV and then spontaneously clear the infection?

Yes. Approximately 15%–25% of people clear the virus from their bodies without treatment and do not develop chronic infection; the reasons for this are not well known. Predictors of spontaneous clearance include:

  • Jaundice 

  • Elevated ALT level 

  • HBV surface antigen (HBsAg) positivity 

  • Female sex 

  • Younger age,

  • HCV genotype 1

  • Host genetic polymorphisms, most notably those near the IL28B gene


How likely is HCV infection to become chronic?

HCV infection becomes chronic in approximately 75%–85% of cases.

Why do most persons remain chronically infected with HCV?

A person infected with HCV mounts an immune response to the virus, but replication of the virus during infection can result in changes that evade the immune response. This may explain how the virus establishes and maintains chronic infection.

What are the chances of someone developing chronic HCV infection, cirrhosis, or liver cancer or dying because of hepatitis C?

Of every 100 people infected with HCV, approximately:

  • 75-85 will go on to develop chronic infection

  • 10-20 will go on to develop cirrhosis over a period of 20-30 years

Among patients with cirrhosis, there is:

  • 1-5% annual risk of hepatocellular carcinoma

  • 3-6% annual risk of hepatic decompensation, for which the risk of death in the following year is 15-20%

Rates of progression to cirrhosis are increased in the presence of a variety of factors: males > females, age >50 years, alcohol, nonalcoholic fatty liver disease, HBV or HIV coinfection, immunosuppressive therapy (24).

Can people become infected with a different strain of HCV after they have cleared the initial infection?

Yes. Prior infection with HCV does not protect against later infection with the same or different genotypes of the virus. This is because people infected with HCV typically have an ineffective immune response due to changes in the virus during infection. For the same reason, no effective pre- or post-exposure prophylaxis (i.e., immune globulin) is available.


Is hepatitis C a common cause for liver transplantation?

Yes. Chronic HCV infection is a common reason for liver transplants in the United States.


How many deaths can be attributed to chronic HCV infection?

In 2016, 18,153 U.S. death certificates had HCV recorded as an underlying or contributing cause of death. However, this is a conservative estimate. Evidence derived from a cohort of patients with known HCV infection who received care at four large healthcare organizations in the United States found that only 19% of decedents had HCV infection listed on their death certificates. More than 70% of these decedents had evidence of moderate to severe underlying liver disease (according to the electronic health record, liver biopsy, or FIB-4 score) and the average age at death was 59 years.

Quick Reference

OSHA provides a very good resource on this subject which can be found here.

What is HIV

HIV stands for human immunodeficiency virus. It weakens a person’s immune system by destroying important cells that fight disease and infection. No effective cure exists for HIV. But with proper medical care, HIV can be controlled. Some groups of people in the United States are more likely to get HIV than others because of many factors, including their sex partners, their risk behaviors, and where they live.