History
HIV Stages
Screening/Testing
USPSTF Recommendations

Historical Background

It is likely that we will never know exactly where, when, and how HIV came into being. The most prevalent theory is that it mutated from SIV (Simian Immunodeficiency Virus), which has been identified in certain subgroups of chimpanzees found in central Africa. The virus was likely transmitted to humans and mutated into HIV when humans hunted these chimpanzees for meat and came into contact with their infected blood. Studies show that HIV may have jumped from apes to humans as far back as the late 1800s. The earliest confirmed case of HIV infection was detected in a blood sample collected in 1959 from a man in Kinshasa, Democratic Republic of the Congo. Over the decades, the virus slowly spread across Africa and later into other parts of the world. We know that the virus has existed in the United States since at least the mid to late 1970s. From 1979-1981 rare types of pneumonia, cancer and other illnesses were being reported by doctors in Los Angeles and New York with male patients sexually active with other men. These were illnesses are not typically found in people with healthy immune systems.

The first reports related to HIV infection in the United States were on June 5, 1981. The Morbidity and Mortality Weekly Report (MMWR) published five cases of Pneumocystis Pneumonia (PCP) in gay men in the Los Angeles, California area. By July 3, 1981, less than one month later, there were 26 additional cases reported. In the December 10, 1981 issue of the New England Journal of Medicine (Links to an external site.), three papers described cases.

The New York Times published an alarming article about the new immune system disorder, which, by that time, had affected 335 people, killing 136 of them. Because the disease appeared to affect mostly gay men, officials initially called it gay-related immune deficiency, or GRID. In 1982 public health officials began to use the term "acquired immunodeficiency syndrome," or AIDS, to describe the occurrences of opportunistic infections, such as Kaposi's sarcoma (a kind of cancer) and Pneumocystis jirovecii pneumonia, in previously healthy people. Formal tracking (surveillance) of AIDS cases began that year in the United States. By 1983, researchers discovered the virus that causes AIDS. The virus was at first named HTLV-III/LAV (human T-cell lymphotropic virus-type III/lymphadenopathy-associated virus) by an international scientific committee. This name was later changed to HIV (human immunodeficiency virus).

"When AIDS Was Funny," is a short film directed and produced by Scott Calonic. It's a bit longer (6:13), but worth the watch to experience how AIDS was perceived at the federal level in a series of White House press briefings:

Public Perception

Though the CDC discovered all major routes of the disease’s transmission, as well as that female partners of AIDS-positive men could be infected, in 1983, the public wrongly considered AIDS a gay disease. It was even called the “gay plague” for many years after. The public's perception teetered on mass hysteria during the 1980's and early 1990's. Because of the widespread fear, ignorance and misinformation about the epidemic, several PSA posters started appearing.

HIV-PrEP-public perception.jpg

Various politicians called for quarantining of anyone who tested positive for HIV, and William F. Buckley infamously penned an op-ed in the New York Times saying that "everyone detected with AIDS should be tattooed." There was an AIDS-quarantine ballot initiative in California, and various states threatened or passed conditional quarantine measures. People living with HIV/AIDS during this time also faced other kinds of discrimination, including the loss of employment and housing, as well as outright violence, including assault and murder. Even healthcare providers were not immune to the hysteria of how HIV was and was not transmitted. Check out this news clip from over 35 years ago:

Some children living with HIV were excluded from school, including Ryan White from Kokomo, Indiana, which is only about 60 miles north of Indianapolis. Ryan became a household name in 1985, when as a 14-year-old he began his successful fight to attend the public school in Kokomo that had banned him amid a clamor of fearful students and their parents (as a hemophiliac, HIV was transmitted to him via a blood transfusion). For months, he had been forced to get his seventh-grade class lessons through a telephone hook-up at home. After he prevailed in court, the boy was taunted at school by other children who wrote obscenities on his locker and shouted insults as he passed in the halls. Vandals broke windows of the family's house and slashed their car's tires. When his mother went to the grocery store, cashiers would throw down her change to avoid touching her hands.

In this TedTalk, you will see how the stigma still persists:

Early AIDS Activism

The rise of AIDS also lead to the rise of AIDS activism. Most of the early activists were those most affected by the disease: gay men and transgender women. These early activists not only endeavored to destigmatize AIDS, but they also endeavored to change the perception that AIDS was God's moral punishment; AIDS was a public health crisis. Additionally those affected by AIDS also became active participants in their own treatments; fighting for the right to be a part of the public discourse that determined HIV/AIDS research. By the end of the decade, in 1989, 27,408 people died from AIDS related illness and complications. A part of the early activism also included public memorials. In 1983, larger metropolitan areas held candlelight vigils to not only honor those who had died from AIDS but also to raise public awareness.

One of the most famous vigils happened by chance. In 1985, Cleve Jones asked people participating in a San Francisco march to place the names of those lost to AIDS on a wall. Upon looking at the wall of names, Jones was struck at how much it looked like the patchwork of a quilt. Inspired by this image, Jones created what would be the first panel of the AIDS Quilt. As word spread, others from cities hard-hit by AIDS starting crafting panels and sending them to Jones. Many people donated equipment, supplies and time. In October 1987, the Quilt was publicly displayed for the first time at the National Mall in Washington, DC. The Quilt had 1,920 panels and was larger than a football field. It is estimated that around 500,000 people visited the Quilt that weekend. Energized by the overwhelming public response, the Quilt was taken on a 20-city tour that raised over $500,000 for AIDS service organizations. In 1988, the Quilt had grown to 8,288 panels in October of that year, it was displayed in front of the White House. Each year, part of this quilt is on display at the Indianapolis AIDS Walk.

Putting a "Straight" Face on HIV/AIDS

It was until 1991 when a "straight" face was associated with HIV/AIDS. It took the announcement of two prominent male, heterosexual athletes for the general public to really understand that HIV and AIDS did not only affect gay men. The first announcement was held on November 7, 1991 when Earvin "Magic" Johnson announced he was HIV positive and his subsequent retirement from the Los Angeles Lakers. That following April, trailblazing tennis champion Arthur Ashe announced he had AIDS. Ashe is the only African American to have won three Grand Slam singles titles at Wimbledon, the US Open Open and the Australian Open.

be sure to complete all tabs of this module before clicking "next"

Overview of HIV

Before we look at the three stages of HIV infection, we are going to do a brief review of HIV and transmission. HIV is classified as a retrovirus. It is composed of genetic material that includes RNA that needs to be converted to DNA to infect human cells. The HIV retrovirus has a central core surrounded by a lipid envelope and characteristic proteins. The incubation period is relatively quick. On Day 0, the HIV exposure occurs. By Day 2, the virus has been collected by the dendritic cells and carried to lymph nodes. Dendritic cells are antigen-presenting cells (also known as accessory cells) of the immune system. Their main function is to process antigen material and present it on the cell surface to the T cells of the immune system. The dendritic cells act as messengers between the innate and the adaptive immune systems. Between Days 4-11, the HIV retrovirus replicates itself in CD4 cells that are released into the body. By Day 11, the virus has spread to other organs within the body. Below is a depiction of the HIV life cycle and how the different classes of drugs target and attempt to disrupt viral replication.

Transmission

Modes of transmission driving the HIV pandemic include sexual, parenteral and perinatal transmission. HIV can be transmitted via blood, semen, pre-seminal fluid, rectal fluid, vaginal fluid and breast milk. It is transmitted via direct fluid contact with a mucous membrane or damaged tissue or must be directly injected into the bloodstream. Susceptible mucous membranes are found inside the rectum, vagina, opening of the penis, the foreskin in an uncircumcised person, and mouth. It can be transmitted/acquired by having penetrative sex with someone living with HIV that has a detectable viral load (primarily anal and vaginal with oral presenting negligible risk). In the United States, sexual contact is the most common source of transmission. Receptive anal sex has the highest likeliness of sexual transmission as the tissue lining the anus is fragile and susceptible to tears during intercourse. Additionally, as part of the GI tract, the rectal tissue houses lymphocytes that HIV targets. Insertive anal sex and receptive vaginal sex are the next likely to offer risk for HIV transmission. The table below has additional information regarding HIV transmission rates. It is important to note that HIV can be transmitted in pre-seminal fluids that may be exchanged during sex. Deep, open-mouthed kissing can also transmit the disease if both people have mouth sores and/or bleeding gums but this is a very uncommon occurrence. Having another sexually transmitted infection can lead to increased risk for acquiring HIV.

Additionally, HIV can be transmitted/acquired by sharing needles and/or syringes with someone who is living with HIV. The virus can live in a needle for up to 42 days. HIV can also spread from exposure of a pregnant person living with HIV to their child during pregnancy, childbirth, or breastfeeding. This type of HIV transmission is called vertical transmission of HIV. HIV cannot be transmitted via mosquitoes, ticks, or other insect bites. HIV is not spread in saliva, tears, sweat, feces, or urine that is not mixed with the blood of a person with HIV.

Probability of HIV Transmission: What are the probabilities of acquiring HIV?

Type of Exposure	Risk per 10,000 Exposures
Sexual Intercourse
Receptive Anal Intercourse	138
Insertive Anal Intercourse	11
Receptive Penile-Vaginal Intercourse	8
Insertive Penile-Vaginal Intercourse	4
Needles/Transfusions
Blood Transfusion	9,250
Needle sharing during injection drug use	63
Percutaneous (needle stick)	23

Three Stages of HIV

HIV-PrEP-stages of HIV.png

Stage 1: Acute HIV

Within 2 to 4 weeks after the initial transmission of HIV, people may experience a flu-like illness, which may last for a few weeks. This is the body’s natural response to infection because the body is trying to fight the virus. HIV is multiplying rapidly and attacking the CD4 cells of the immune system. Symptoms during this acute stage can include:

fever
body rash
sore throat
swollen glands
headache
upset stomach
joint aches and pains
muscle pain

When people are in this stage, they have a large amount of virus in their blood which leads to higher rate of transmission. It is during this stage that active viral replication occurs. People with acute infection are often unaware that they are living with HIV because of the rather common symptoms, or they may not feel sick at all. Only antigen/antibody tests or nucleic acid tests (NATs) can diagnose an acute infection.

Stage 2: Chronic HIV

This period is sometimes called clinical latency or asymptomatic HIV. During this phase, HIV is still active but reproduces at very low levels. The host's immune response controls the viral replication. The CD4 cell count is gradually declining during this stage. People may not have any symptoms or get sick during this time. For people who are not taking medicine to treat HIV, this period can last anywhere from six months to a decade or longer, but some may progress faster. During this phase, the virus is slowly destroying the immune system. It is important to remember that people can still transmit HIV to others during this phase, although people who are on ART and are undetectable, cannot sexually transmit HIV to their partners. At the end of this phase, a person’s viral load starts to go up and the CD4 cell count begins to go down. As this happens, the person may begin to have symptoms as the virus levels increase in the body. At this point, they will move into stage 3. People who take HIV medication as prescribed may never move into stage 3.

Stage 3: Acquired Immunodeficiency Syndrome (AIDS)

This is the most severe stage of HIV. People living with AIDS have such badly damaged immune systems that they get an increasing number of severe illnesses called opportunistic infections. To receive an AIDS diagnosis, the person’s CD4 cell count will be below 200 cells/mm, or they will develop certain opportunistic infections. Without treatment, people living with AIDS typically survive about 3 years. Their viral load will be high and due to this, the person will be very infectious. During this phase, the person my experience any of the following symptoms:

weight loss
chronic diarrhea
night sweats
fever
persistent cough
mouth and skin problems
regular infections
serious illnesses or diseases

Common Opportunistic Infections

Candidiasis
Invasive cervical cancer
Coccidioidomycosis
Cryptococcosis
Cryptosporidiosis
Cytomegalovirus (CMV)
Encephalopathy-HIV related
Herpes simplex virus (HSV)
Histoplasmosis
Kaposi’s sarcoma
Lymphoma
Tuberculosis
Mycobacterium avium complex
Pneumocystis pneumonia
Pneumonia
Progressive multifocal leukoencephalopathy
Salmonella septicemia
Toxoplasmosis
Wasting syndrome due to HIV

be sure to complete all tabs of this module before clicking "next"

Screening/Testing

Who Should Be Tested?

The below Clinicians Chat video from the CDC features Dr. Oni Blackstock, MD, MHS, a physician in the Infectious Disease Clinic at Harlem Hospital, and Ariel Watriss, MSN, NP-C, a nurse practitioner in College Health at Tufts University. They discuss the importance of routine HIV screening to improve patients’ health outcomes and provide practice tips on how to start the conversation about HIV screening with patients.

The CDC recommends HIV testing for all persons seeking STI evaluation who are not already known to have HIV. Testing should be routine at the time of STI evaluation. CDC and USPSTF recommend HIV screening at least once for all persons aged 15-65. Persons at higher risk for HIV acquisition should screened at least annually. Physicians may consider the benefits of offering more frequent screening (eg. every 3-6 months). All pregnant patients should be tested for HIV. HIV testing should be voluntary and free from coercion. Patients should not be tested without their knowledge. Opt-out HIV screening (notifying the patient that an HIV test will be performed, unless the patient declines) is recommended in all healthcare settings. Screening is recommended with laboratory based antigen/antibody combination assay. If unlikely to follow-up, a rapid point of care test is useful. Physicians should test for HIV RNA if initial testing according to the HIV testing algorithm recommended by CDC is negative or indeterminate when concerned for acute HIV infection.

What are the Desired Outcomes of Routine HIV Screening?

An estimated 1.2 million people in the US have HIV, including about 158,500 people who are unaware of their status. Nearly 40% of new HIV infections are transmitted by people who don't know they have the virus. The goals of routine HIV screening are two-fold: to improve the quality of life and survival of patients who are living with HIV and decrease the risk of transmission to others. Prompt referral of individuals living with HIV to medical care is a critical step in this process. In an effort to increase the likelihood that a person living with HIV will access treatment and care, plus reduce the chance of transmitting HIV to others, the CDC, through their revised recommendations, seeks to increase the number of physicians offering routine HIV screening as a standard part of care.

What are the Benefits to Routine Screening?

Doing risk-based screening has failed to identify a substantial proportion of people with living with HIV early in disease. Additionally, risk assessment and prevention counseling are rather resource intensive. The HIV/AIDS epidemic affects all populations, and risk-based testing can fail to identify HIV in some patients. The CDC’s recommendations address the drawbacks and limitations of risk-based testing and simplify the process for providers, thereby ensuring better detection of HIV. There are also situations where patients do not always disclose or may not be aware of their risk. According to Bernstein, et, al (2008), 39% of men who had sex with a man within the past year did not disclose it to their health care provider. In another example, Lyss, et al (2007) found that 51% of rapid test positive patients identified in emergency department screening had no identified risk.

Check out this video for medical students on HIV pre-test counseling:

What Happens After the Test Results are In?

Preliminary positive screening tests for HIV should be followed by supplemental testing to establish the diagnosis. Physicians should not assume that a laboratory report of a negative HIV Ag/Ab or antibody test indicates that the requisite HIV RNA testing for acute HIV infection has been conducted. They should consider explicitly requesting HIV RNA testing when concerned about early acute HIV infection.

When diagnosis is confirmed, patients need to be told they are living with HIV. This may or may not fall to the physician. Many of you will take classes or workshops on how to deliver a life changing diagnosis. We are not going to teach anything that you won't learn in your profession. However, people living with HIV are still unfortunately stigmatized. The diagnosis of HIV can carry additional weight that let's say a cancer diagnosis does not.

Caitlin Frazier wrote a piece for the The Atlantic titled, "What It's Like to Tell Someone They Have HIV." In the article, she writes:

You’ve just been cast as a character in a major moment of someone’s life. You don’t want to do or say the wrong thing. Once when I was anxiously preparing to disclose a positive result, an HIV-positive volunteer overheard me. “It doesn’t matter exactly what you say,” he said. “He won’t hear anything after the word ‘positive.’”

On a bigger level, telling someone that he or she is HIV positive is one of the best things you can do to fight the spread of the virus. There are a couple ways to think about HIV testing. One is that you’re providing a service to the community: people come in, you test them, you give them results and/or referrals, and then they leave. But another way to think about testing is that you are on the front lines of stopping the virus: you are looking for people who are at high risk for HIV, testing them, and then if they test positive, you make sure they transition immediately into a continuum of care.”

Now the patient needs to be told they are HIV positive. This may or may not fall to you in your medical career. Many of you will take classes or workshops on how to deliver a life changing diagnosis. Keep in mind that people infected with HIV are still unfortunately stigmatized. The diagnosis of HIV can carry additional weight that let's say a cancer diagnosis does not.

Types of Diagnostic Tests

There are three main types of HIV tests: combination antigen/antibody tests, nucleic acid tests (NATs), and antibody tests. All tests are designed to detect HIV-1, which is overwhelmingly the most common type of HIV in the United States. Some antibody tests and the combination test can also detect HIV-2 infections, which are less common in the U.S. No test is perfect; tests may be falsely positive or falsely negative or impossible to interpret ("indeterminate," see below).

HIV Antibody Test: HIV possesses many unique proteins on its surface and inside the virus itself. When someone is living with HIV, their body produces substances designed to neutralize the virus. These substances are called antibodies, and they are directed against the unique proteins of HIV. These tests are designed to detect HIV antibodies in the oral fluid, whole blood, or plasma of a person living with HIV. Further testing must be done to confirm an HIV diagnosis. These tests take 23 to 90 days to detect HIV after exposure.

NATs look for the actual virus in the blood. This test is expensive and is not routinely used for HIV screening unless the person recently had a high-risk exposure or a possible exposure with early symptoms of HIV. This test can detect HIV 10 to 33 days after exposure.

Combination Antigen/Antibody HIV Test: The HIV combination test detects antibodies directed against HIV-1 or HIV-2, as well as a protein called p24, which forms part of the core of the virus. This is important because it takes weeks for antibodies to form after the initial infection, even though the virus (and the p24 protein) is present in the blood. Thus, combination testing may allow for earlier detection of HIV. An antigen/antibody test performed by a laboratory on blood from a vein can usually detect HIV infection 18 to 45 days after an exposure. There is also a rapid antigen/antibody test available that is done with a finger prick. Antigen/antibody tests done with blood from a finger prick can take longer to detect HIV (18 to 90 days after an exposure). The graph below illustrates when these diagnostic tests can detect HIV infection.

Window Period for Antibody Tests

When using a test that only detects HIV antibodies, it is important to discuss the window period with the person being screened. The window period is the time between infection and the development of antibodies. When a person is infected with HIV, it takes a few weeks for the body to make antibodies to the virus. An HIV antibody test performed during the window period may be negative, even though the patient may have high levels of virus in their blood. Most people develop antibodies within a month of infection, although some people can take up to 3 months. In very rare cases, it can take 6 months for the test to be positive. In general, repeat testing for HIV should occur at 3 months if there is a significant concern of recent HIV infection. Additionally, because the level of virus in the blood is high during the window period, people can more easily transmit HIV.

USPSTF Recommendations

The process followed by the USPSTF to determine the evidence for preventive services includes: first to conduct a scientific review of clinical preventive services; next to estimate the magnitude of benefits and harms for each preventive service and to determine the net benefit; and finally to issue a recommendation. The strength of evidence is quantified by the task force and given a grade:

“A” means a prevention item is strongly recommended
"B” is recommended
“C” is not recommendation for or against
“D” is recommendation against
“I” indicates that there is insufficient evidence to recommend either for or against the specific service

be sure to complete all tabs of this module before clicking "next"

back to top