Body Fluid Exposures

Blood and any body fluid visibly contaminated with blood should be considered capable of transmitting hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV). Semen and vaginal secretions should also be considered potentially able to transmit these viruses. Similarly, cerebrospinal fluid, amniotic fluid, pleural fluid, synovial fluid, and peritoneal and pericardial fluids carry a significant risk of transmitting these viruses.

In contrast, unless blood is visibly present, saliva, sputum, sweat, tears, feces, nasal secretions, urine, and vomitus carry a very low risk for transmission of HCV and HIV. It should be noted that saliva can also carry HBV. ^[1] (See Pathophysiology.) Federal guidelines do not recommend testing for and giving Post-Exposure Prophylaxis (PEP) for HIV for exposure to non-bloody saliva. However, the federal guidelines are not clear regarding testing and prophylaxis for HBV and HCV for saliva exposure. The PEP Quick Guide for Occupational Exposure/National Clinician Consultation Center does not recommend testing or treating for HBV and HCV exposure for non-bloody saliva but does not recommend against it. ^[2]  

Occupational transmission of blood-borne infections may also occur through parenteral, mucous membrane, and non-intact skin exposure. The greatest risk for transdermal transmission is via a skin penetration injury that is fairly deep and sustained with a sharp hollow-bore needle that has visible blood on it that had recently been removed from a blood vessel of a patient with a high viral load. ^[3] Although many infectious agents may be transmitted by such contact, the most consequential include HBV, HCV, and HIV. (See Pathophysiology and Prognosis.)

In addition, skin and soft-tissue infection at the site of the inoculation, through introduction of staphylococcal species, is an issue of concern and must not be neglected. Tetanus prophylaxis is also an important issue of concern. Another important issue is the fact that many medical institutions adopt clinical pathways, algorithms, and plans for management of their own health care personnel but are woefully lacking when faced with the outside individual at significant risk for these diseases from needlesticks, mucous membrane splashes, or sexual encounters. (See Treatment and Medication.)

Zika virus has emerged as a pathogen of greater notice, as the incidence of this infection has increased in the Caribbean and Brazil. Consequently, there is greater interest of Zika virus being imported into the Unites States by travelers from these areas. Although most individuals with Zika virus infection are asymptomatic or have a benign viral illness characterized by fever, rash, arthralgia, and conjunctivitis, it can cause severe brain defects, such as microcephaly, in the fetuses of women who become infected with Zika virus during pregnancy. These defects may cause fetal demise. Zika virus infection in adults has been associated with Guillain-Barré syndrome and meningoencephalitis.

Although Zika virus is mainly transmitted via infected mosquitos, it has also been shown to be transmitted by sexual contact (especially from men to women [including from asymptomatic men]) and by blood, including from mother to fetus. A 2019 study conducted in Puerto Rico showed that the 95th percentile for the time until the loss of Zika virus RNA detection was 54 days in serum, 34 days in urine, and 81 days in semen. Few participants had detectable Zika virus RNA in saliva or vaginal secretions. The CDC recommends that the minimum interval from potential exposure to Zika virus and blood donation is 120 days. The CDC also recommends that men with possible Zika virus exposure, regardless of symptom status, should abstain from sexual contact or should use condoms for at least 6 months. Finally, the CDC recommends that women who have been infected or exposed to Zika virus wait at least 8 weeks from symptom onset or last possible exposure to Zika virus before attempting conception. ^[4]  There are other diseases besides the above that can be transmitted by body fluids, including syphilis and other STI’s, monkeypox, malaria, Ebola, and other hemorrhagic fevers. Healthcare providers must be aware of emerging infections that may been brought from an affected region by travelers. ^[5]  In this chapter, we will mainly discuss HIV, HBV, and HCV infections.

Healthcare personnel include employees, volunteers, attending clinicians, students, contractors, and any public safety workers whose activities involve contact with patients and their environment such that exposure to blood or other body fluids can occur. Nurses, trainees, and students are at especially high risk for significant morbidity from these exposures. ^{[6, 7, 8]} There are about 385,000 percutaneous injuries a year in US Hospitals. ^[9]  About two-thirds of procedures performed in the ED have the potential to result in healthcare personnel exposure to blood or body fluid, and most of those involve the hands. ^[10]  

Non–healthcare personnel may be exposed by way of social interaction, sexual encounters (including sexual assault), trauma scenarios, intentional inoculations consistent with contemporary terrorist activity, or drug abuse. A flow chart for the management of body fluid exposure is shown below.

Flowsheet for management of blood/body fluid exposures.

Infection risk

Body fluid exposures carry a risk of transmitting HIV, HBV, and HCV. The risk of developing HIV after a needlestick injury involving an HIV-infected patient is around 0.3%. Factors that increase the odds of HIV transmission after percutaneous exposure include a deep injury, the presence of visible blood on the instrument causing the exposure, injury via a needle that was placed in a vein or artery of the source patient, and terminal illness in the source patient. ^{[11, 12]} Viral titers are also very high during the initial stages of infection, when seroconversion is taking place. ^[13] Wearing gloves may reduce (>50%) the volume of blood introduced through an injury. (See Prognosis.)

Note that the risk for HIV transmission in healthcare workers from exposure of the mucosa to HIV-infected fluids was extremely low (0.09%) and that no cases of HIV conversion after exposure of intact skin to HIV-contaminated fluids or from bites (unless visible blood was present) were reported. ^[14]

When intact, the integumentary system serves as an effective physical barrier to the entry of infectious elements into the body. However, a special situation exists in terms of mucous membranes. Across these membranes lies a layer of mucus secreted by specialized columnar cells that are closely associated with each other through gap junctions. These junctions are little more than specialized cell surface projections that allow intercellular communication.

The presence of a moist mucous layer tends to prolong the viability of fragile viruses, such as HIV and HBV, which cannot survive long in drier environments. However, HBV has been found to be capable of surviving on countertops for 7 days, and HBV remains capable of causing infection, ^[15] whereas HCV has been shown to be able to survive on environmental surfaces for a minimum of 16 hours, but not for as long as 4 days. ^[16]

Higher vascularity coupled with a relatively permeable cellular layer gives rise to a presumed heightened risk for transmission of HBV, HCV, or HIV across mucous membranes and into the bloodstream.

After initial exposure, animal models have shown that HIV replicates within dendritic cells of the skin and mucosa within the first 48 hours before spreading through lymphatic vessels and becoming a systemic infection. This interval from initial introduction of the virus to systemic spread provides an opportunity to inhibit the replication of the virus using PEP. ^[17] In addition, some individuals who are exposed to HIV or HCV may have the ability to clear these infections due to inherent cellular immunity and may not demonstrate an antibody response to these organisms. This is referred to as aborted infection. ^[13]

Fortunately, viral transmission is rare in cases of occupational HIV exposures. Intact keratinized skin does not possess the mucous membrane characteristics that encourage the transmission of HIV, and it is virtually impermeable unless disrupted.

Most exposures are caused by a departure from universal precautions on some level, whether they are the result of recapping or of failure to use personal protective equipment or are due to a sharp unintentionally left in an inappropriate place or placed in the wrong container for disposal. (See Presentation.)

Blood exposure is a particularly high risk during surgical procedures (up to 6.3 exposures per 1000 surgical procedures). Risk factors for blood exposure during surgical procedures increase with higher levels of patient blood loss, longer procedure duration, higher number of surgical personnel involved in the procedure, and the use of suture needles rather than other device types. The use of blunt surgical needles, when appropriate, reduced the risk for blood exposure from needlesticks, as did the use of double gloving for certain procedures. ^[18]

It has also been recommended that oculofacial plastic surgeons strongly consider using eye protection during procedures that have the potential to cause “splash exposures." ^[19]

Although the incidence of body fluid exposures and percutaneous injuries have been significantly reduced overall, likely owing to safety-engineered devices, these devices are still associated with a significant number of percutaneous injuries. More prevention strategies and education are still needed in this area. ^[20] One strategy that may help prevent these injuries is calling a “surgical time out” and making a “high-risk announcement” when there is a high risk for needlestick injuries during a surgical procedure. Procedures that were found to be high risk included administering skin injections, placing intravenous catheters, drawing blood, recapping needles, and using sharp suture needles. ^[21]

Safety during autopsies is another subject that has not received much publicity. The “Autopsy Checklist” is a standardized way of documenting safety and risk management issues during the autopsy process. However, the effectiveness of this procedure relies on the accurate completion of this list, which often goes undone. ^[22]

Recently, because of the Ebola virus and severe acute respiratory syndrome (SARS) outbreaks, there has been a great deal of publicity concerning the use of personal protection equipment (PPE). Unfortunately, no high-quality studies have addressed which types of equipment protect best, the best way to don and doff the PPE, and how to ensure that healthcare workers (HCWs), who are at a higher risk for these diseases than the general population, use them properly. It appears that more active training on the use of PPE is needed by HCWs. ^[23] One method for studying the effectiveness of PPE, along with the best way to don and doff this equipment by providers, is by using UV tracers. ^[24]

When dealing with blood and body fluid exposures, document whether the exposure represents a departure from universal precautions or Occupational Safety and Health Administration (OSHA) standards or whether it represents a true accident (eg, projectile vomiting, precipitous labor with spontaneous rupture of membranes). This information is vital to the institutional safety committee, whose function is to monitor the safety of the environment for the entire facility and make recommendations for upgrades and policy changes.

In the United States, sharps injuries occur at a rate of 1.8 per year per physician and 0.98 per year per nurse while working on the same medical ward. Statistically, however, twice as many nurses as doctors have been reported with occupationally acquired HIV infection. Whether this is a function of the significance of the exposure (ie, severity of the stick) or the route of exposure remains to be studied.

In a retrospective study of first responders presenting to an ED for body fluid or blood exposure, the incidence was 23.29 ED visits per 100,000 ambulance runs. ^[25]

Body fluid exposures appear to be a significant problem in developing countries, but no reliable statistics are available. A 2019 study from India showed that fatigue due to working excessive hours was a major risk factor for needlesticks among junior medical officers. ^[26]

Prognosis is associated with risk for infection and its sequelae. This is difficult to specify in any given patient. However, since the risk for HIV transmission is less than 1%, the prognosis of any given patient exposed to HIV may be listed as good but may remain so only with vigilant follow-up and consistent use of prophylaxis against infection.

Patients who develop hepatitis or HIV infection face significant morbidity and mortality. However, meaningful treatments now exist for HIV, HBV, and HCV infections.

Morbidity and mortality

Healthcare workers who have a significant exposure to HBV (ie, inoculation with an open-bore needle from a source known to have active HBV disease) but have not previously received HBV vaccine and do not receive PEP have a 6%-30% risk of becoming infected, depending on the presence of hepatitis B e antigen (HBeAg). The HBV viral DNA level correlates better with the infectivity of HBV than does the presence of HBeAg. ^[13]

The risk for HCV transmission from a known HCV-positive source by a sharps injury is 0%-7%. Approximately 80% of those infected with HCV will develop active liver disease, and 10%-20% will develop cirrhosis; 1%-5% of cirrhosis cases will lead to liver cancer over a period of years. ^[27]

As noted above, the rate of HIV transmission from a known infected individual via a sharps injury is 0.3%, whereas that for exposure to mucous membrane is 0.09%. ^[28] The rate is higher if the injury was sustained by a hollow-bore needle, if the injury was deeply penetrating, or if blood was injected during the injury. Risk to the injured health care worker is greater if the source patient had a high HIV viral load and/or a lower CD4 count.

Complications

The main complication of body fluid exposure is acquisition of hepatitis and HIV infection. Acquiring a significant bacterial skin infection from a needlestick also is possible. The risk of acquiring tetanus is extremely low.

Education regarding universal precautions and safety protocols to employees prior to any body fluid exposure may prevent exposures. Although universal guidelines have decreased the incidence of needlesticks, these injuries have continued to occur, albeit at a much lower rate. The healthcare workers at highest risk include surgeons, emergency room personnel, laboratory room professionals, and nurses. In many cases, the needlestick injuries occur because of failure to follow safety guidelines on the proper use and disposal of sharps. Many needlesticks are preventable by strictly following established procedures. ^[29]

Once the patient has been exposed, the patient must be educated regarding the risks, in addition to the risks versus benefits of postexposure prophylaxis (PEP).

If the patient opts for HIV PEP, the importance of adherence for 28 days must be emphasized. Also, the patient should understand to return to the emergency department (ED) immediately for any complications of the body fluid exposure or the PEP regimen. The importance of outpatient follow-up should be stressed to the patient.

For additional patient education information, see Hepatitis B, Hepatitis C, and HIV/AIDS.