HIV Transmission and Infection Control
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HIV Transmission and Infection Control
Copyright © 2015 Wild Iris Medical Education, Inc. All Rights Reserved.
COURSE OBJECTIVE: The purpose of this course is to prepare healthcare professionals to prevent the transmission of HIV infection.
Upon completion of this course, you will be able to:
- Identify the routes of transmission of the human immunodeficiency virus (HIV).
- Discuss the risk factors for transmission of HIV.
- Identify preventive and risk-reduction measures for HIV infection.
- Describe infection control systems for HIV in the healthcare setting and in the home.
- Summarize infection control practices when caring for those with HIV in the home.
TABLE OF CONTENTS
The human immunodeficiency virus (HIV) is the cause of AIDS. DNA analysis has identified the HIV-1 virus as originating in a substrain of chimpanzees in west equatorial Africa (Gao et al., 1999). Scientists theorize that HIV-1 moved from chimps to humans when hunters were exposed to infected blood while handling bush meat (the flesh of various primates, including chimps and gorillas). Once in the human population, HIV quickly became a global pandemic, driven by travel and migration patterns, sexual practices, drug use, war, and economics.
Strains of HIV
There are at least two types of HIV virus: HIV-1 is the cause of AIDS, and HIV-2 is a related group of viruses found in West African patients that is less easily transmitted. Worldwide, the predominant virus is HIV-1. Most of the West Africans infected with HIV-2 show none of the symptoms of classical AIDS. Viral load tends to be lower in persons infected with HIV-2, which may explain this type’s lower transmission rates and nearly complete absence of perinatal transmission. Most persons infected with HIV-2 do not develop AIDS, although when they do, the symptoms are indistinguishable from HIV-1. A few cases of HIV-2 infections have been found in people in the United States.
HIV mutates readily, leading to many different strains of HIV, even within the body of a single infected person. Based on genetic similarities, the numerous viral strains may be classified into types, groups, and subtypes. HIV-1 comprises four distinct groups: M, N, O, and P. Group M was the first to be discovered and represents the pandemic form of HIV-1 (Sharp & Hahn, 2011).
Although the mechanisms of HIV and the way it affects the immune system are not fully understood, the primary event is the entrance of HIV into the body’s CD4 cells (T-Helper lymphocytes, also called T4 cells). These white blood cells are essential to the function of the immune system in fighting infection. Once inside a T4 cell, HIV replicates and signals other cells that produce antibodies, which are essential for immune system function. It is not known whether HIV replication directly kills the infected cells or the anti-HIV immune response destroys them, but HIV demolishes the T4 cells and damages their ability to signal for antibody production. Thus, it steadily deactivates the immune system, leading to dysfunction of various organ systems.
Acute HIV infection is the time period immediately following infection with the virus. HIV replication is very rapid in the 6–8 weeks after acquiring the HIV infection and results in a high amount of HIV in the blood (viral load). During this time, the infected person may be symptom-free and unaware of the infection, but the viral load is the highest it will ever be because the body’s defenses have not yet responded. It is at this time when the risk of contagion is much higher than that from patients with established infections (Cohen et al., 2011). Once infected, the person remains infectious for life.
Some researchers use the term acute HIV infection to describe the 6- to 12-week interval between initial infection and production of antibodies that can be detected by an HIV test. Others refer to this period as primary HIV infection, acute retroviral syndrome, or acute HIV syndrome. This interval is also called the window period. During this period the person can infect other people through unprotected anal or vaginal sex, oral sex, or sharing of needles. Following this period, the person can remain asymptomatic for many years before the start of symptomatic AIDS.
Contrary to myths and misinformation, HIV is not transmitted by casual contact such as hugging, other nonsexual touching, and the shared handling of objects. Insects do not carry HIV, nor is the virus transmitted through air or water. HIV is a relatively fragile virus. Once outside the human body, HIV has a very short lifespan, which makes most medical procedures and caregiving activities safe if standard infection control procedures are followed.
In terms of the classic “chain of infection,” three links are necessary for the transmission of HIV:
- An HIV source
- A sufficient dose (viral load) of virus
- Access to the bloodstream of another person
Varying levels and concentrations of HIV have been found in most body fluids of infected persons, including blood, semen, saliva, tears, breast milk, and vaginal and cervical secretions. However, only blood, semen, breast milk, and vaginal and cervical secretions have been proven to transmit HIV infection. Healthcare workers, however, may be exposed to some other body fluids with high concentrations of HIV, including amniotic, cerebrospinal, pericardial, pleural, and synovial fluids.
Transmission of HIV occurs primarily through sexual contact with an infected person. This includes anal, oral, and vaginal contact. The risk of transmission depends on sexual practices. Receptive anal contact without a latex condom carries the greatest risk, probably because of the larger surface area of mucous membranes involved. Receptive partners are at greater risk for transmission of any sexually transmitted disease, including HIV.
Since last reported in 2006, there have been no confirmed cases of female-to-female transmission of HIV, but female sexual contact should be considered a possible means of transmission of HIV.
Health professionals need to remember that sexual identity and gender preference do not always predict behavior and that women who identify as lesbian may still be at risk for HIV through unprotected sex with men or with injection drug users.
Injection Drug Use
Sharing injection needles, syringes, and other paraphernalia with an HIV-infected person can send HIV directly into the user’s bloodstream (along with hepatitis B and C viruses and other bloodborne diseases). Paraphernalia with the potential for transmission include the syringe, needle, “cooker,” cotton, and/or rinse water (sometimes called works).
Transmission also occurs through indirect sharing of contaminated paraphernalia and/or dividing a shared or jointly purchased drug while preparing and injecting it. “Indirect sharing” includes squirting the drug back from a dirty syringe into the drug cooker and/or someone else’s syringe, or sharing a common filter or rinse water.
Transmission of HIV through transfusion has been uncommon in the United States since 1985 and in other countries where blood is screened for HIV antibodies. In 1999, about 1% of U.S. AIDS cases were caused by transfusions or use of contaminated blood products. The majority of those cases were in people who received blood or blood products before 1985.
Donor screening, blood testing, and other processing methods have reduced the risk of transfusion-caused HIV transmission. All donated blood is tested for HIV. Also, other measures are used to screen possible donors. For example, donors are questioned about whether they have any signs and symptoms of HIV or HIV risk factors. Only about 1 in 2 million donations might carry HIV and transmit HIV if given to a patient (NIH, 2012).
Tattooing and Blood-Sharing Activities
HIV can be transmitted during tattooing or during blood-sharing activities such as “blood brothers/sisters” rituals or ceremonies where blood is exchanged or unsterilized equipment contaminated with blood is shared. The CDC reported no cases of HIV transmission documented from tattooing or body piercing, but these activities do present a risk if new needles, ink, and other supplies are not used and the person doing the procedure is not properly trained and licensed.
Pregnancy and Breastfeeding
A pregnant woman who is infected can transmit HIV to her fetus. After delivery, an infected mother can transmit HIV to her infant while breastfeeding. Women newly or recently infected with HIV, or those in the later stages of AIDS, tend to have higher viral loads and may be more infectious.
When a woman’s healthcare is monitored closely and she receives a combination of antiretroviral therapy, the risk of perinatal transmission to the newborn drops below 1%. Other measures to prevent perinatal transmission include the use of prophylactic cesarean delivery before onset of labor or rupture of membranes and avoidance of breastfeeding by HIV-infected mothers (CDC, 2013a). Alternatively, a simple method of flash-heating pumped breast milk has been shown to inactivate the HIV virus (Israel-Ballard et al., 2007). In addition, the infant is treated for the first six weeks of life (NIH, 2013).
Some states require that pregnant women be counseled concerning risks about HIV and offered voluntary HIV testing. A healthcare practitioner experienced in treating HIV-infected women should give advice about medications and cesarean delivery on a case-by-case basis.
FLASH-HEATING BREAST MILK
- Collect breast milk into a clean glass jar.
- Cover the jar immediately.
- Place the covered jar into a cooking pan.
- Put enough water into the pan to cover the jar halfway up.
- Bring the water to a boil.
- Protecting hands, immediately remove the jar from the water.
- Allow milk to cool before feeding to the infant.
Source: Israel-Ballard et al., 2007.
Biting poses little risk of HIV transmission unless the person who is biting and the person who is bitten have an exchange of blood (such as through bleeding gums or open sores in the mouth). However, bites can transmit other infections and should be treated immediately by thorough washing of bitten skin with soap and warm water and disinfection with antibiotic skin ointment.
|Type of Exposure||HIV Infection Risk*|
|Source: CDC, 2013b.|
|HIV-infected blood transfusion||90%|
|Needle-sharing during injection drug use||0.67%|
|Receptive anal intercourse||0.5%|
|Receptive penile-vaginal intercourse||0.1%|
|Insertive anal intercourse||0.07%|
|Insertive penile-vaginal intercourse||0.05%|
|Receptive oral intercourse||Low|
|Insertive oral intercourse||Low|
|Throwing body fluids (including semen or saliva)||Negligible|
|Sharing sex toys, razors, toothbrushes||Negligible|
|*1% risk means a likelihood of 1 in 100 for infection to occur; 0.1% means a likelihood of 1 in 1,000.|
FACTORS AFFECTING TRANSMISSION RISK
Many other factors, alone or in combination, affect the risk of HIV transmission.
Other Sexually Transmitted Diseases (STDs)
Infectious organisms transmitted during sexual activity—and the clinical manifestations arising from them—cause sexually transmitted diseases. Bacteria, parasites, and viruses cause STDs. There are more than 20 types of STDs, including:
- Bacterial: chlamydia, gonorrhea, syphilis
- Fungal: candidiasis (yeast infection)
- Viral: hepatitis B, Herpes simplex, HIV, HPV
- Parasites: crab louse, scabies
- Protozoal: trichomoniasis
Sexually transmitted diseases increase the risk of acquiring HIV infection because they can cause lesions that make it easier for HIV to enter the body. They can also cause inflammation triggered by the immune system. Because HIV prefers to infect immune cells, any disease causing an increase in these cells will make it easier for a person to become infected with HIV. HIV-positive individuals with STDs are also more infectious and are 3 to 5 times more likely to transmit HIV during sexual activities (CDC, 2010a).
Prevention of HIV infection should be part of a general program of STD prevention because other preventable STDs, most of which are curable, have also reached epidemic proportions, particularly among sexually active young people. For example, rates of primary and secondary syphilis (the stages when syphilis is most infectious) in males have increased each year between 2000–2011. Seventy-two percent of all primary and secondary syphilis cases were among men who have sex with men (MSM) (CDC, 2013c).
Screening for STDs is also critical since many of those infected do not show symptoms. This includes Pap tests for sexually active women and a thorough history of STDs during medical diagnostic studies for both women and men. Prompt treatment should follow for any persons who test positive for STDs. Treatments vary with each disease or syndrome. Because of the risk of developing resistance to medications for certain STDs, healthcare providers should check the latest STD treatment guidelines, available on the CDC website.
HUMAN PAPILLOMA VIRUS (HPV)
Human papilloma virus is highly prevalent among HIV-infected women and men, increasing viral shedding and raising the risk of cervical and anal cancers. Multiple strains of this virus are often present in HIV-positive women. Pre-existing HPV infection in women is associated with a two-fold increase in the risk of HIV acquisition. HPV infection of the penis among heterosexual men almost doubles the risk of contracting HIV, and anal HPV infection among gay/bisexual men more than triples the risk of contracting HIV (Houlihan et al., 2012).
A study completed in 2012 supports recommendations to vaccinate young HIV-positive women with Gardasil and to target vaccination to 11- and 12-year-olds, who are less likely to have acquired HIV behaviorally (Mascolini, 2012). Gardasil and Cervarix have been found safe for use in HIV-positive patients with high-grade anal intraepithelial neoplasia (AIN), a precancerous condition caused by infection with high-risk forms of HPV. In October 2009, the FDA approved Gardasil to prevent HPV in boys and men ages 9–26; and in 2010 the CDC recommended vaccination of boys and men ages 9–26 to reduce their likelihood of acquiring genital warts (CDC, 2010b).
Genital herpes (HSV-1 and -2) also appear to be a major risk factor for acquiring HIV infection, increasing the risk more than two-fold. The CDC (2011) estimates that 776,000 people in the United States get new herpes infections every year. One out of 6 people aged 14–49 are estimated to have genital HSV-2 nationwide. Genital HSV-2 infection is more common in women than in men. Most have not been diagnosed. Many of them have mild or unrecognized infections but shed virus intermittently in the genital tract. These individuals are more likely to transmit the infection.
Two large, randomized controlled trials found that, for people with HSV-2 infection, taking daily treatment to suppress herpes infection did not lower the chances of getting HIV infection. Thus, testing for genital herpes and treatment with herpes medications will not diminish the potential risk of HIV acquisition due to HSV-2 infection (CDC, 2011).
CHLAMYDIA AND GONORRHEA
In 2012 chlamydia was the most frequently reported bacterial sexually transmitted infection in the United States. Untreated chlamydia may increase a person’s chances of acquiring or transmitting HIV (CDC, 2014). It is estimated that 1 in 15 sexually active females aged 14–19 has chlamydia, which is transmitted through anal, vaginal, or oral sex and can be passed from an infected woman to her baby during childbirth. Gonorrhea often occurs along with chlamydia. It is spread by contact with infected body fluid and can be passed from a woman to her newborn during childbirth. It is estimated that less than half of all new cases are reported to the CDC, as gonorrhea may be asymptomatic. Sexually active teenagers have one of the highest rates of reported infections.
The individual with multiple sex or injection drug–sharing partners is at great risk for exposure to HIV. Anyone having unprotected sex with multiple partners (defined by CDC as six or more partners in a year) is considered at high risk for HIV/AIDS infection. However, unprotected sex with even one infected partner risks transmission.
Use of Noninjecting Drugs
Use of any mood-altering substance—including prescribed medications, alcohol, or noninjectable street drugs such as methamphetamine—can increase risk of HIV transmission by impairing judgment, thereby leading to risky behaviors such as unprotected sex. Methamphetamine abuse is growing among MSM, especially younger MSM.
Certain substances can mask pain and/or create oral and genital sores. For example, methamphetamine dries mucous membranes and increases the risk of abrasions (Hussain et al., 2012).
Gender, Culture, and Equality Issues
The balance of power in an intimate relationship can affect an individual’s ability to insist on safer sex practices such as condom use. Women who are socially and economically dependent on men may be unable to negotiate condom use or to leave a relationship that puts them at risk.
Culturally imposed ignorance about their bodies, especially about sexuality and reproduction, can make women even more vulnerable to HIV infection. Some cultures endorse the concept of multiple sexual partners for men but monogamous relationships for women.
PREVENTION AND RISK REDUCTION
HIV infection is preventable. For example, screening of blood and blood products for the HIV virus has reduced the risk of HIV transmission with transfusion to 1:1,000,000. Mother-to-baby transmission has dropped to a rate of less than 1% and less than 1 transmission per 100,000 live births (CDC, 2013a). Following Standard Precautions in healthcare has unquestionably prevented thousands, if not millions, of cases of HIV/AIDS in the United States. But, because the virus is transmitted through behaviors that many people find pleasurable—sexual activity and injection drug use—prevention is difficult.
Prevention of HIV/AIDS saves money as well as lives. The CDC estimates that the average cost of lifetime treatment for one person with HIV infection varies from $253,000 to $402,000 (Farnham et al., 2013).
Prevention of HIV begins with education and counseling about sexual practices and injection drug use. People unable to “just say no” need basic, practical, how-to information.
Safer sex practices include:
- Abstinence from sexual contact
- Mutual monogamy
- Correct use of latex condoms for all sexual intercourse (anal, oral, and vaginal), even between two HIV-positive partners
- Getting tested and knowing the HIV status of one’s partner
Latex condoms are highly effective against HIV. If a partner is allergic to latex, polyurethane or polyisoprene condoms can be used. “Skins,” or natural-membrane condoms, used for birth control, however, will not protect against the virus.
Although there have been no confirmed cases of female-to-female transmission of HIV, women who have sex with women
- Using female condoms consistently and correctly each and every time for sexual contact or when using sex toys
- Not sharing sex toys
- Using natural-rubber latex sheets, dental dams, cut-open condoms, or plastic wrap during oral sex; however, no barrier methods for use during oral sex have been shown to be effective by the FDA
- Knowing one’s own and one’s partner’s HIV status; this can help uninfected women reduce their risk of becoming infected and assist those who are infected to get early treatment and avoid transmitting the virus to others
CORRECT USE OF MALE CONDOMS
Both women and men may need instruction in the correct use of condoms:
- Use a new latex condom for each act of intercourse.
- Leave space at the tip of the condom as a receptacle for semen and to decrease the risk of condom breakage.
- Hold on to the base of the condom to prevent slippage when withdrawing the penis after ejaculation.
- Do not attempt intercourse with a condom if the penis is only partly erect.
OLDER ADULTS AND CONDOM USE
Most sexually active older couples do not use condoms because they are unconcerned about pregnancy. Unless a couple is monogamous, however, unprotected sex increases the risk of infection with HIV or other sexually transmitted diseases from multiple sexual partners. Older women face a higher risk than older men because age-related vaginal thinning and dryness can cause tears in the vaginal area.
Perceived barriers to condom use among seniors include the following factors:
- Drug and/or alcohol use before or during sexual activity
- Belief that unprotected sexual activity is more exciting and that condoms reduce sexual pleasure
- Lack of knowledge about effective use of condoms
- HIV conspiracy beliefs that HIV/AIDS is a man-made virus that the government created to kill and wipe out black people (Bogart et al., 2011)
- Belief that known and/or trusted partners are “safe”
Studies indicate these beliefs exist in all races and ethnic groups.
Injection drug users who refuse treatment or who have no treatment programs available to them need instructions about precautions:
- Do not share needles or other paraphernalia.
- If sterile needles are not available, use bleach to clean needles.
- Be aware that anyone who knowingly exposes others to HIV/AIDS endangers the public health and may be taken into custody, tested for HIV without consent, hospitalized, and isolated.
These risk-reduction measures also apply to people who use needles to inject insulin, vitamins, steroids, or prescription or nonprescription drugs.
In December 2009, new U.S. legislation ended the ban on federal funding for needle exchange programs, making additional resources available to states and communities. HIV experts called this a crucial, lifesaving step forward for HIV prevention. But in 2011, only two years after a landmark decision to allow federal funding for syringe exchange programs, the ban was renewed as part of a political compromise on a general spending bill. The reinstatement of the ban fails to take into account countless studies on the efficacy of such programs as HIV-prevention strategies.
Syringe exchange or needle exchange programs also help prevent spread of hepatitis and other bloodborne pathogens. Currently, 29 states have syringe or needle exchange programs, including many local health departments.
Preventing Transmission to Uninfected Partners
Optimal care of people with HIV/AIDS includes not only antiviral therapies, health maintenance, and referral to support services, but also an emphasis on prevention of transmission to uninfected partners. The CDC recommends that anyone with HIV/AIDS use prevention strategies even if his or her partner is also HIV infected. The partner may have a different strain of the virus that could behave differently in each individual or that could be resistant to different anti-HIV medications.
Healthcare practitioners should implement preventive strategies with their patients beginning with the initial visit and continuing throughout subsequent visits or periodically, at least once a year. A straightforward, nonjudgmental approach and open-ended questions should be used to screen and assess patient behaviors associated with HIV transmission. Other strategies include self-administered questionnaires and computer-, audio-, or video-assisted questionnaires.
Initial and periodic screening for STDs should also be performed. At the initial visit, both men and women should have laboratory tests for syphilis. Women should also be screened for trichomoniasis, and women age 25 and younger should be screened for cervical chlamydia, the most common STD among women. Screening for STDs, particularly for chlamydia, should be repeated periodically if the patient is sexually active. Women younger than 19 are often reinfected with chlamydia, probably by male partners who have not been diagnosed and treated because the disease is asymptomatic.
HIV-positive women of childbearing age should be screened for pregnancy at initial and subsequent visits and asked about interest in future pregnancy and use of contraceptives. Counseling about reproductive healthcare or prenatal care, as appropriate, should be offered.
Injection drug users should be referred for substance abuse treatment. Those who refuse treatment should be counseled to use once-only sterile syringes and not to share needles with others.
Prevention among Minority Populations
African Americans and Hispanics of both sexes have disproportionately higher rates of HIV/AIDS in the United States. There are no biologic reasons for these disparities, and there is no single reason why these disparities exist. However, there are a number of contributing factors, including:
- Health disparities, linked to socioeconomic conditions
- Distrust of the healthcare system, based on historical abuses of people of color
- Difficulty communicating health education in culturally appropriate ways to diverse communities
- Denial about HIV risk due to stigma about the disease and its connection to homosexuality and drug use
Prevention messages need to be culturally appropriate and relevant and they must be delivered through channels appropriate to individual communities. These channels may include religious institutions or respected elders in the community.
Research has documented that male circumcision significantly reduces the risk of contracting HIV through penile-vaginal sex. Studies have shown circumcised men had a 58% lower incidence of HIV infection compared with uncircumcised men. Male circumcision also lowers the risk for other STDs (CDC, 2013d).
In July 2012, the U.S. Food and Drug Administration (FDA) approved the combination medication tenofovir disoproxil fumerate plus emtricitabine (TDF/FTC), a combination pill known as Truvada, for use as preexposure prophylaxis (PrEP) to prevent new infections. In addition, in 2013 the CDC reported that daily medication with tenofovir disoproxil fumerate has now been proven to reduce the risk of acquiring HIV among all groups at high risk, including people who inject drugs, by 49% (CDC, 2013e).
The cost of PrEP is a major concern for public health agencies and private insurers, since Truvada costs about $1,200 per month. In addition, possible side effects include diarrhea, kidney, and bone damage. It is warned that this drug should not replace safer sex practices that include using condoms and preventing impaired judgment.
Risks for Occupational Exposure
Healthcare workers may be infected with HIV through needlesticks or direct contact with HIV-infected blood—for example, through a break in the skin or through the eyes or the mucosal lining of the nose.
In 2013 the CDC reported that 57 healthcare personnel in the United States have been documented as having seroconverted to HIV following occupational exposures. In addition, 143 possible cases of HIV infection or AIDS have occurred among healthcare personnel. However, there have been no confirmed cases of occupational HIV transmission to healthcare workers reported since 1999. Healthcare workers exposed to HIV-infected blood at work have a 0.3% risk of becoming infected (CDC, 2013f).
Healthcare professionals who work in correctional institutions and in home care are at higher risk for occupational exposure to HIV and other bloodborne pathogens than those who work in other settings. Other occupational groups with potential exposure to HIV (as well as HBV and HCV) include, but are not limited to:
- Law enforcement
- Fire, ambulance, and other emergency responders
- Morticians and embalmers
- Ancillary medical facility personnel such as housekeeping, waste management, laundry staff
The risk of developing HIV infection from a needlestick with infected blood is about 1 in 300 without prompt antiretroviral treatment, and the risk increases with:
- Deep punctures
- Hollow-bore needles
- Visible blood on the needle
- High viral load in the source
(Comparatively, the risk after a mucous membrane exposure is about 1 in 9,000, and the risk of HIV transmission after nonintact skin exposure is estimated to be less than the risk for mucous membrane exposure.)
According to the CDC, the risk of infection varies on a case-by-case basis. Factors affecting the risk include:
- Whether the exposure was from a hollow-bore needle or other sharp instrument
- Whether it involved exposure to nonintact skin or to mucous membranes (such as eyes, nose, and/or mouth)
- The amount of blood involved
- The amount of virus present in the source’s blood
IN CORRECTIONAL INSTITUTIONS
The high prevalence of HIV infections in correctional institutions increases the risk of exposure, as does the environment itself. The CDC and the National Institute for Occupational Safety and Health (NIOSH) cite these challenges:
- Jails and prisons can be unpredictable work settings.
- Security issues are often a higher concern than infection control.
- Inmates may have a higher rate of bloodborne diseases.
Correctional healthcare workers can be bitten or stabbed during an inmate assault, punctured with a used needle, or splashed in the face with blood. Exposure to bloodborne pathogens can happen in any of these situations.
The federal Occupational Safety and Health Administration (OSHA) Bloodborne Pathogens Standard (29 CFR 1910.1030) prescribes safeguards to protect workers against health hazards related to bloodborne pathogens. It includes regulations dealing with exposure control plans, engineering and work practice controls, hepatitis B vaccination, hazard communication and training, and recordkeeping. The standard imposes requirements on employers of workers who may be exposed to blood or other potentially infectious materials (OPIM) such as certain tissues and body fluids.
Most states have adopted standards that are identical to federal OSHA. Twenty-five states, Puerto Rico, and the Virgin Islands have OSHA-approved state plans, which are required to be at least as effective as federal OSHA.
In general, the standard requires employers to:
- Establish a written exposure control plan to eliminate or minimize occupational exposures and to update the plan annually
- Implement the use of Standard Precautions (treating all human blood and OPIM as if known to be infectious for bloodborne pathogens)
- Identify and use engineering controls (devices that isolate or remove bloodborne pathogens hazards from the workplace)
- Identify and ensure the use of work practice controls
- Provide personal protective equipment (PPE) and clean, repair, and replace this equipment as needed
- Make available hepatitis B vaccinations to all workers with occupational exposure
- Make available postexposure evaluation and follow-up to any occupationally exposed worker who experiences an exposure incident
- Use labels and signs to communicate hazards
- Provide information and training to workers on occupational exposures
- Maintain worker medical and training records
OTHER POTENTIALLY INFECTIOUS MATERIALS
Bloodborne pathogens include any human pathogen present in human blood or other potentially infectious materials (OPIM). OPIM linked to transmission of HIV, HBV, and HCV are listed here. Standard Precautions apply to all of the following:
- Blood and blood products
- Vaginal secretions
- Cerebrospinal fluid
- Synovial fluid
- Pleural fluid
- Peritoneal fluid
- Pericardial fluid
- Amniotic fluid
- Saliva in dental procedures
- Any body fluid or substance visibly contaminated with blood
- All body fluids in situations where it is difficult or impossible to differentiate between body fluids
- Any unfixed tissue or organ (other than intact skin) from a human (living or dead)
- HIV-containing cell or tissue cultures, organ cultures, and HIV- or HBV-containing culture medium or other solutions; and blood, organs, or other tissues from experimental animals infected with HIV or HBV
Body fluids such as urine, feces, and vomit are not considered OPIM unless visibly contaminated by blood. Similarly, wastewater (sewage) has not been implicated in the transmission of HIV, HBV, or HCV and is not considered to be either OPIM or regulated waste.
Infection Control Systems
To prevent HIV transmission in healthcare settings, the CDC instituted “Universal Precautions” (blood and body fluid precautions) in the 1980s. Under Universal Precautions, healthcare personnel assumed that the blood and other body fluids from all patients were potentially infectious and therefore followed infection-control precautions at all times and in all settings.
In 1996, this practice was replaced. Standard Precautions is the current terminology, and it includes:
- Precautions to be used with all patients at all times and in all settings
- Transmission-based precautions to be used when specific modes of transmission are present (e.g., Contact Precautions or Droplet Precautions)
The emphasis has shifted to a more pragmatic focus on what healthcare professionals need to do with specific patients with specific modes of transmission associated with their diagnosis.
These precautions include:
- Routine use of barriers (such as gloves and/or goggles) when anticipating contact with blood or body fluids
- Washing hands and other skin surfaces immediately after contact with blood or body fluids
- Careful handling and disposing of sharp instruments during and after use
USE OF BARRIERS
Gloves, masks, protective eyewear, and chin-length plastic face shields are examples of personal protective equipment (PPE). PPE shall be provided and worn by employees in all instances where they will or may come into contact with blood or OPIM. This includes, but is not limited to, dentistry, phlebotomy, processing of any body fluid specimen, and postmortem (after death) procedures.
Latex gloves are recommended when dealing with blood or OPIM. However, people with allergies to latex must be provided with nitrile, vinyl, or other glove alternatives that meet the definition of “appropriate” gloves. Gloves must be changed after each client.
Gloves should be worn:
- When working with blood, blood products, semen, vaginal secretions, and any other potentially contaminated body fluids, such as cerebrospinal fluid, amniotic fluid, and saliva, as well as any items or surfaces in contact with the aforementioned fluids
- When touching mucous membranes or breaks in the skin
- When performing or assisting with any invasive procedures, such as venipuncture, surgery, or repair of traumatic injury
- When working in situations where hand contamination may occur, such as with an uncooperative or aggressive patient
- When the healthcare practitioner has cuts, scratches, or other breaks in their own skin
Clinicians with weeping dermatitis (such as poison ivy or poison oak) or exudative lesions must be prohibited from all patient care and/or handling of patient care equipment or supplies.
Masks, goggles, face shields, and gowns should be worn:
- During all invasive procedures and any procedure in which blood or body fluids may spatter or become airborne
- During procedures in which heavy bleeding or other extensive fluid loss (such as peritoneal fluid) may occur; a disposable plastic apron or gown and boots are also recommended
Reusable PPE must be cleaned and decontaminated or laundered by the employer. Lab coats and scrubs are generally considered to be worn as uniforms or personal clothing. When contamination is reasonably likely, protective gowns should be worn. If lab coats or scrubs are worn as PPE, they must be removed as soon as practical and laundered by the employer.
Soap-and-water handwashing must be performed whenever hands are visibly contaminated or there is a reasonable likelihood of contamination. Standard Precautions also include frequent handwashing with warm water and soap:
- Before seeing each patient
- Immediately after gloves are removed, even if they appear to be intact
- Immediately, if contaminated with blood or other body fluids to which Standard Precautions apply
- Upon leaving and returning to the work area
- Before and after using restroom facilities
It is advisable to keep fingernails short and wear as little jewelry as possible.
Additional information on hand hygiene can be found in the CDC “Guideline for Hand Hygiene in Healthcare Settings” (CDC, 2002) (see “References” at the end of this course).
CAUTIONS REGARDING ALCOHOL-BASED HAND SANITIZERS
The use of an alcohol-based hand rub is appropriate in many, but not all, situations.
- Alcohol-based hand sanitizers are not effective against all pathogens, notably the spores of C. difficile and anthrax, and have limited effectiveness against norovirus (winter vomiting virus).
- The presence of protein material on the skin prevents the active ingredient from contacting the skin. Soap-and-water handwashing is recommended after known or suspected contact with blood or other body fluids and after eating to remove any protein from the skin.
Sharps containers should be placed as close to the point of use as possible to enhance compliance with correct disposal policies.
Needles are not to be recapped, purposely bent or broken, removed, or otherwise manipulated by hand. After they are used, disposable syringes, needles, scalpel handle-blade units, and removable scalpel blades are to be immediately placed in puncture-resistant, labeled containers for disposal.
Phlebotomy or injection needles must not be removed from holders or syringes unless required by a medical procedure. The intact phlebotomy or injection needle and holder or syringe must be placed directly into an appropriate sharps container.
Adhere to agency protocols for disposal of infectious waste.
HOUSEKEEPING AND WASTE DISPOSAL
The work area of the facility is to be maintained in a clean and sanitary condition. The employer is required to determine and implement a written schedule for cleaning and disinfection, based on the location within the facility, type of surface to be cleaned, type of soil present, and tasks or procedures being performed.
Disinfectants. All equipment and all environmental and working surfaces must be properly cleaned and disinfected after contact with blood or OPIM. Chemical germicides and disinfectants in recommended dilutions must be used to decontaminate spills of blood and other body fluids. Consult the Environmental Protection Agency (EPA) for lists of registered sterilants, tuberculocidal disinfectants, and antimicrobials with HIV/HBV efficacy claims to verify that the product used is appropriate (see "Resources" at the end of this course).
Laundry. Laundry that is or may be soiled with blood/OPIM must be treated as contaminated. Contaminated laundry must be bagged at the location where it was used and shall not be sorted or rinsed in patient-care areas. It must be placed and transported in bags that are labeled or color-coded (red-bagged).
Laundry workers must wear protective gloves and other appropriate personal protective clothing when handling potentially contaminated laundry. All contaminated laundry must be cleaned or laundered so that any infectious agents are destroyed.
Regulated Waste. Potentially contaminated broken glassware or sharp items must be removed using mechanical means, such as a brush and dustpan or vacuum cleaner. All regulated waste must be placed in closeable, leak-proof containers or bags that are color-coded (red-bagged) or labeled as required by law to prevent leakage during handling, storage, and transport. Disposal of waste shall be in accordance with federal, state, and local regulations.
Regulated waste is defined as any of the following:
- Liquid or semiliquid blood or other potentially infectious materials (OPIM)
- Contaminated items that would release blood or OPIM in a liquid or semiliquid state, if compressed
- Items that are caked with dried blood or OPIM and are capable of releasing these materials during handling
- Contaminated sharps
- Pathological and microbiological wastes containing blood or OPIM
TAGS AND LABELS
Tags or labels must be used as a means to protect employees from exposure to potentially hazardous biological agents.
All required tags must meet the following specifications:
- Tags must contain a signal word or symbol and a major message.
- The signal word shall be “BIOHAZARD,” or the biological hazard symbol (below).
- The signal word must be readable at a minimum of five feet or such greater distance as warranted by the hazard.
- The tag’s major message must be presented in either pictographs, written text, or both.
- The signal word and the major message must be understandable to all employees who may be exposed to the identified hazard.
- All employees must be informed as to the meaning of the various tags used throughout the workplace and what special precautions are necessary.
Personnel handling laundry and waste are to be aware that these items may contain sharps despite the most stringent policies and the best efforts of healthcare workers. They should be trained in immediate first aid for a needlestick or other break in skin integrity. They should immediately report any potential exposure to a supervisor with the knowledge and authority to implement the exposure control plan.
Eating, drinking, smoking, applying cosmetics or lip balm, and handling contact lenses are prohibited in work areas that carry the potential for occupational exposure.
Food and drink must not be stored in refrigerators, freezers, or cabinets where blood or OPIM are stored or in other areas of possible contamination.
Protocols for Exposure to Blood or OPIM
Any healthcare worker who receives a needlestick or other significant exposure to potential HIV, HSV, or HBV infection should follow the employer’s protocol, which is based on guidelines issued by the U.S. Public Health Service (Kuhar, 2013).
Immediately after exposure to blood or OPIM of a patient:
- Wash the affected area(s) with soap and water. Application of antiseptics should not substitute for washing.
- Flush splashes to the nose, mouth, or skin with water.
- Irrigate eyes with clean water, saline, or sterile irrigants.
- Remove any potentially contaminated clothing as soon as possible.
- In the event of a sharps injury, wash the exposed area with soap and water.
- Do not “milk” or squeeze the wound.
- There is no evidence that antiseptics such as hydrogen peroxide will reduce the risk of transmission; however, use of antiseptics is not contraindicated.
- Seek emergency treatment if the wound needs suturing.
- For bites or scratch wounds, wash with soap and water and cover with a sterile dressing. All bite wounds should be evaluated by a healthcare professional.
- Exposure to urine, feces, vomitus, or sputum is not considered a bloodborne pathogens exposure unless the fluid is visibly contaminated with blood. Follow the employer’s procedures for cleaning these fluids.
REPORTING THE INCIDENT
Immediately report the incident to a supervisor and to the department (e.g., occupational health, infection control) within the agency responsible for managing exposures. Prompt reporting is essential because in some cases postexposure prophylaxis (PEP) may be recommended and started as soon as possible. Discuss with a healthcare professional the extent of the exposure, treatment, follow-up care, personal prevention measures, the need for a tetanus shot, and other care.
In some states, employers must make a confidential postexposure medical evaluation available to employees who report an exposure incident. Workers may also have a right to file a worker’s compensation claim for exposure to bloodborne pathogens.
POSTEXPOSURE PROPHYLAXIS (PEP)
Postexposure prophylaxis is recommended when occupational exposure to HIV occurs. The U.S. Public Health Service (USPHS) recommends the following guidelines:
- Determine, if possible, the HIV status of the exposure source patient to guide the need for HIV PEP.
- Start PEP medication regimens as soon as possible after exposure (24 hours) and continue for a 4-week duration.
- PEP medication regimens should contain three or more antiretroviral drugs for all occupational exposures to HIV.
- Expert consultation is recommended for any occupational exposure to HIV situation as defined by the USPHS.
- Close follow-up should be provided, including counseling, baseline and follow-up HIV testing, and monitoring for drug toxicity beginning 72 hours after exposure.
- If a fourth-generation combination of HIV p24 antigen-HIV antibody test is used for follow-up HIV testing, testing may be ended four months following exposure. If a new testing platform is not available, follow-up HIV testing is to be concluded six months after exposure.
Frequent advances in treatment make it impractical to list medications and dosages here. PEP can only be obtained from a licensed healthcare provider. The employing facility may have recommendations and procedures in place for staff members to obtain PEP. After evaluation, certain anti-HIV medications may be prescribed.
Round-the-clock information regarding the most current PEP regimen is available from the Post-Exposure Prophylaxis Hotline (PEPline): 1-888-448-4911.
The PEPline offers treating clinicians up-to-the-minute advice on managing occupational exposures (i.e., needlesticks, splashes, etc.) to HIV, hepatitis, and other bloodborne pathogens. Clinicians will help assess the risk of the exposure, discuss the most recent PEP protocols, and review specific treatment and follow-up options. Written materials supporting the telephone discussion are sent by mail or fax whenever needed.
PEPline clinicians will respond to calls between 9 a.m. and 2 a.m. ET. Emergency calls made during other hours are answered when live service resumes the following morning.
The PEPline is an invaluable resource for healthcare workers and their agencies, especially in rural areas. The phone number and website should be listed in appropriate locations, and a plan put in place to contact the PEPline using a relay of information if cellular and/or internet service is not available in all areas in which workers may be exposed.
Source: CDC, 2013g.
Some states may require the employer to arrange to test the source individual—the person whose blood or OPIM an employee was exposed to—for HIV, HBV, and HCV as soon as feasible. Such testing may or may not require the consent of the source individual, depending on state laws.
Source testing does not eliminate the need for baseline testing of the exposed individual for HIV, HBV, HCV, and liver enzymes. Initiating PEP should also not be contingent upon the results of a source’s test. Current recommendations are to provide immediate PEP in certain circumstances, with possible discontinuation of treatment based on the source’s test results.
INFECTION CONTROL IN THE HOME
Healthcare professionals and other caregivers who care for HIV patients at home or in home-like settings are also at risk of exposure to HIV and other bloodborne pathogens. Nurses, nursing assistants, personal care assistants, and family members experience percutaneous injuries and other exposures to blood and body fluids during care of an HIV-infected person.
Medical procedures contributing to percutaneous injuries in home care include injecting medications, performing fingersticks and heelsticks, and drawing blood. Other contributing factors include sharps disposal, contact with waste, and patient handling.
Healthcare workers and other caregivers who care for HIV patients should practice good hygiene techniques in preparing food, handling body fluids, and using medical equipment. Cuts, accidents, or other circumstances can result in spills of blood/OPIM on carpeting, vinyl flooring, clothing, skin, or other surfaces. Everyone, even young children, needs to have a basic understanding that they should not put their bare hands in or on another person’s blood.
Gloves and Handwashing
Gloves (latex, vinyl, or nitrile in the case of latex allergy) should be worn whenever a caregiver anticipates contact with any body substance (blood/OPIM) or nonintact skin. Gloves are not necessary for general care or during casual contact (serving food, bathing intact skin). Never rub the eyes, mouth, or face while wearing gloves.
Gloves should be properly removed and disposed of and hands washed as soon as possible after care of each patient. Disposable gloves should never be washed and reused. Correct handwashing is critically important.
Cleaning Blood/OPIM from Surfaces
Wear appropriate gloves when cleaning blood from skin surfaces. Use sterile gauze or other bandages and follow normal first-aid techniques to stop the bleeding. After applying the bandage, remove the gloves slowly so fluid particles do not splatter or become aerosolized. Hands should be cleaned using either soap and water or an alcohol-based hand sanitizer as soon as possible.
On bare floors, pretreat body fluid spills with full-strength liquid disinfectant or detergent; then wipe up with either a mop and hot soapy water or appropriate gloves and paper towels. Dispose of paper towels into a well-marked plastic bag or heavy-duty container. Broken glass should be swept up using a broom and dustpan (never bare hands).
Use a disinfectant (such as 1 part household bleach freshly mixed with 9 parts water) to disinfect the area where the spill occurred. If a mop was used for cleaning, soak it in a bucket of hot water and disinfectant for the recommended time. Empty mop water into the toilet, not the sink. Sponges and mops used to clean up body fluid spills should not be rinsed in the kitchen sink or in a location where food is prepared.
PREPARING A 1:10 SOLUTION OF HOUSEHOLD BLEACH
A 1:10 solution of household bleach includes 1 part bleach and 9 parts water. The key is using the same volume as a “part”—i.e., a measuring tablespoon or a measuring cup.
- Working in well-ventilated area, measure 9 parts water into a closable container that will hold the total volume of solution.
- Measure 1 part of household bleach into the same container.
- Close and label the container with the name of the solution (one which everyone in the household can read and understand), the date and time prepared, and an identifier for the person preparing the solution.
- Prepare only as much solution as needed for 24 hours.
- When using, pour solution from the container.
- Do not return used solution to the container.
- Discard any unused solution within 24 hours, rinse the container, and prepare new solution as needed.
Source: CDC, 2009.
On carpeting, pour dry kitty litter or another absorbent material onto the spill to absorb the body fluid. Carefully pour carpet-safe liquid disinfectant onto the contaminated carpeting and leave it there for the amount of time indicated in manufacturer’s instructions. Using sturdy rubber gloves, blot the spill with paper towels until it is absorbed. Vacuum normally afterward.
Clothes, washable uniforms, towels, or other laundry stained with blood/OPIM should be washed and disinfected before further use. If possible, have the patient remove the clothing. If necessary, use appropriate gloves to assist with removing the clothes.
If the washing machine is not close by, transport the soiled items in a sturdy plastic bag. Then place the items in the washing machine and soak or wash them in cold, soapy water to remove any blood from the fabric. Hot water will permanently set blood stains.
Use hot water for a second washing cycle and include detergent, which will act as a disinfectant. Dry the items in a clothes dryer. Wool clothing or uniforms may be rinsed with cold soapy water, then dry-cleaned to remove and disinfect the stain.
Toilet and Bedpan Safety
It is safe to share toilets/toilet seats without special cleaning, unless the surface becomes contaminated with blood/OPIM. If this occurs, spray the surface with a solution of 1:10 bleach solution. Wearing gloves, wipe the seat dry with disposable paper towels.
Persons with open sores on their legs, thighs, or genitals should disinfect the toilet seat after each use. Urinals and bedpans should not be shared between family members unless these items are thoroughly disinfected after each person’s use.
Use a new pair of gloves to change diapers. Discard disposable diapers in an appropriate plastic bag or receptacle, along with gloves. Wash hands immediately after changing the diaper. Disinfect the diapering surface. Wash cloth diapers in very hot water with detergent and a cup of bleach, and dry them in a hot clothes dryer.
Electronic thermometers with disposable covers do not need to be cleaned between uses for the same individual unless visibly soiled or if there is evidence that the cover integrity has been compromised. Wipe the surface with a disinfectant if necessary. Glass thermometers should be washed with soap and warm water before and after each use. If the thermometer will be shared among family members, after each use it should be soaked in 70%–90% ethyl alcohol for 30 minutes, then rinsed under a stream of warm water.
Personal Hygiene Items
People should not share razors, toothbrushes, personal towels or washcloths, dental hygiene tools, vibrators, enema or douche equipment, or other personal care items.
Safe and Legal Disposal of Sharps
Syringes, needles, and lancets are called sharps, and their disposal is regulated. Sharps can carry hepatitis, HIV, and other bacteria and viruses that cause disease. Throwing them in the trash or flushing them down the toilet can pose health risks for others—such as sanitation (garbage) workers, other utility workers, and the public—from needlesticks and illness. Rules and disposal options vary according to circumstances, so it is essential to check with the local health department to see which option applies to any given situation.
Parents and caregivers should make sure that children understand never to touch a found needle or syringe but to immediately ask a responsible adult for help.
Safe disposal of found syringes should follow these guidelines:
- Do not pick up a found syringe or needle with bare hands. Use gloves and tongs, shovel, or a broom and dustpan to pick it up. Hold the needle away from the body.
- Do not break the needle off from the syringe.
- Place used sharps and syringes in a safe container with at least a one-inch opening and a lid that will seal tightly, such as an empty plastic laundry detergent container or glass bottle or jar. If a glass jar is used, place it in a larger plastic bucket or container that has a tight-fitting lid. Soda cans are not good containers to use because people often try to recycle discarded cans. Do not flush needles or syringes down the toilet.
- Tape the container shut for added safety and label it with the warning: “SHARPS, DO NOT RECYCLE!” Place it well out of reach of children.
- Call the local health department to determine what disposal sites are available.
Anyone with an accidental needlestick requires a prompt assessment by a medical professional. Testing for HIV, HCV, and HBV may be recommended. If someone finds and handles a syringe, but no needlestick occurs, testing for HIV is not necessary.
In the United States, HIV is most commonly transmitted through specific sexual behaviors (anal or vaginal sex) or sharing needles with an infected person. It is less common for HIV to be transmitted through oral sex or for an HIV-infected woman to pass the virus to her baby. It is also possible to acquire HIV through exposure to infected blood, transfusions of infected blood, blood products, or organ transplantation, though this risk is extremely remote due to rigorous testing of the U.S. blood supply and donated organs.
HIV/AIDS is preventable, but because the virus is transmitted through behaviors that many people find pleasurable—sexual activity and injection drug use—prevention is difficult. Prevention of HIV begins with education and counseling about sexual practices and injection drug use.
The risk of healthcare workers being exposed to HIV on the job is very low, especially if they carefully follow Standard Precautions. It is important to remember that casual, everyday contact with an HIV-infected person does not expose healthcare workers or anyone else to HIV. For healthcare workers on the job, the main risk of HIV transmission is through accidental injuries from needles and other sharp instruments that may be contaminated with the virus; however, even this risk is small.
Although preventing exposures to blood and body fluids is the primary means of preventing occupationally acquired HIV infection, appropriate postexposure management is an important element of workplace safety.
HIV/AIDS (Centers for Disease Control and Prevention)
Post-Exposure Prophylaxis Hotline (PEPline): 1-888-448-4911
Selected EPA-registered disinfectants (Environmental Protection Agency)
NOTE: Complete URLs for references retrieved from online sources are provided in the PDF of this course (view/download PDF from the menu at the top of this page).
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