Teen Newsletter: December 2020 – Domestic HIV/AIDS

HIV can affect anyone regardless of sexual orientation, race, ethnicity, gender, or age. However, certain groups are at higher risk for HIV and merit special consideration because of particular risk factors.

HIV (human immunodeficiency virus) is a virus that attacks the immune system by destroying CD4+ T cells, a type of white blood cell that is vital to fighting off infection. The virus is spread by contact with certain bodily fluids of a person with HIV, most commonly during unprotected sex (sex without a condom or HIV medicine to prevent or treat HIV), or through sharing injection drug equipment. A member of the genus Lentivirus, HIV is separated into two serotypes, HIV-1 and HIV-2. HIV-1 is the most common type of HIV and accounts for 95% of all infections, whereas HIV-2 is relatively uncommon and less infectious.

If left untreated, HIV can lead to the disease AIDS (acquired immunodeficiency syndrome). Some people have flu-like symptoms within 2 to 4 weeks after infection (called acute HIV infection). But some people may not feel sick during acute HIV infection. The only way to know if someone has an HIV infection is by getting tested.

There are currently three types of HIV tests. One is the nucleic acid test, or NAT, that looks for the actual virus in the blood and involves drawing blood from a vein. The test can either tell if a person has HIV or tell how much virus is present in the blood (known as an HIV viral load test). While a NAT can detect HIV sooner than other types of tests, this test is very expensive and not routinely used for screening individuals. The second is an antigen/antibody test that looks for both HIV antibodies and antigens. Antibodies are produced by your immune system when you’re exposed to viruses like HIV. Antigens are foreign substances that cause your immune system to activate. If you have HIV, an antigen called p24 is produced even before antibodies develop. This lab test involves drawing blood from a vein. There is also a rapid antigen/antibody test available that is done with a finger prick. And finally, there is an HIV antibody test. It only looks for antibodies to HIV in your blood or oral fluid. In general, antibody tests that use blood from a vein can detect HIV sooner after infection than tests done with blood from a finger prick or with oral fluid. Most rapid tests and the only currently approved HIV self-test are antibody tests. More information on HIV testing.

The human body cannot get rid of HIV and no effective HIV cure exists. So, once you have HIV, you have it for life. However, by taking HIV medicine (called antiretroviral therapy or ART), people with HIV can live long and healthy lives and prevent transmitting HIV to their sexual partners. In addition, there are effective methods to prevent getting HIV through sex or drug use, including pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP). Prophylactic treatment for any disease means to treat for the disease after potential exposure. Be sure to do this month’s digital scavenger hunt activity for a guided exploration of the pre- and post-exposure medications!

Public health problems are diverse and can include infectious diseases, chronic diseases, emergencies, injuries, environmental health problems, as well as other health threats. Regardless of the topic, we take the same systematic, science-based approach to a public health problem by following four general steps. Let’s explore a case study on HIV/AIDS using this approach.

1. Surveillance (What is the problem?)

In public health, we identify the problem by using surveillance systems to monitor health events and behaviors occurring among a population.

CDC collects, compiles, and analyzes information on HIV activity year-round in the United States through several reporting systems, but this case study will focus on data reported through the Enhanced HIV/AIDS Reporting System (eHARS).

HIV is a notifiable disease, meaning doctors’ offices, clinics, and all testing facilities are required to report new cases of HIV infection to state health departments through the eHARS system. This web-based system assists health departments with reporting, data management, analysis, and transfer of data to CDC. CDC then analyses the data to look for clusters of new HIV cases, and to compare these data to rates of infection earlier in the year or past years to see if there are increases in numbers or a change in what type of population is being infected. These data are then provided back to each state for local programs to use, though some states do their data analyses. At times, if appropriate, CDC may send epidemiologists to investigate in the community, but more often CDC provides data analysis, advice called technical assistance, and provides funding for HIV prevention programs.

Data from eHARS is compiled into HIV surveillance reports—for example, the number and population rates of HIV diagnoses, the number of people living with HIV, and the number of people who are receiving HIV medical care. The report provides information like the map below, which shows the rate of HIV infections per 100,000 persons in 2018.

The data is also analyzed according to age, gender, race/ethnicity, and sex (at birth) and transmission category. Below you can see the 2018 data broken down according to race/ethnicity. From the larger graph we see that the Black/African American population has the highest incidence. Also note that the smaller inset is due to the difference in scale on the Y axis.

Below is the breakdown of data according to age. From the graph we can see highest incidence was within the 25-34 years age group, and that for several other age groups the rates decreased slightly.

Analyzing data helps CDC and other public health entities create programs for the populations most at risk for HIV infection.

2. Risk Factor Identification (What is the cause?)

After we’ve identified the problem, the next question is, “What is the cause of the problem?” For example, are there factors that might make certain populations more susceptible to disease, such as something in the environment or certain behaviors that people are practicing?

In this step, we, the collective public health community, consider why people in this community are testing positive – are they doing anything that is putting them at risk? For example, in one community a cluster of new HIV cases was detected in a homeless encampment. The investigation also revealed that a medical clinic nearby offered PrEP for HIV prevention. Earlier in this newsletter, you learned that PrEp, if taken every day, provides a 99% protection against HIV, so it could be easy to assume that the HIV infections in this community should be low. However, investigations into this cluster revealed that persons living in the area were often afraid to leave their tents or the encampment area for fear of their possessions being taken, either by others living nearby or in a city-mandated clean up. For HIV prevention this is problematic for several reasons. First, a person must be evaluated by a medical professional before being prescribed PrEP and the PrEP medications must be taken daily. If persons are afraid of leaving their areas and are afraid that their possessions may be taken, they may not be willing to go see the medical professionals for the initial evaluation, and they could have trouble keeping their supply of pills.

3. Intervention Evaluation (What works?)

Once we’ve identified the risk factors related to the problem, we ask, “What intervention works to address the problem?” We look at what has worked in the past in addressing this same problem and if a proposed intervention makes sense with our affected population.

In our scenario of persons who are homeless, local or state organizations may consider what ways they could support persons who are homeless. Examples of programs they could evaluate are ways in which to bring medical professionals to the encampment, housing options, or ways to help these individuals keep their medication supplies safe. Part of the evaluation of intervention strategies would involve determining funding for possible programs.

4. Implementation (How did we do it?)

In the last step, we ask, “How can we implement the intervention? Given the resources we have and what we know about the affected population, will this work?”

In this step, CDC would work with partner agencies or groups by funding programming such as mobile HIV testing groups, mobile medical clinics, and prescription lockers to allow persons experiencing homelessness to have a safe place to store ART or PrEP medications.

Much of the work CDC does is to provide data for local groups to implement in their communities. Read this article of how Boston University’s School of Social work implemented mobile medical teams across the U.S. to serve persons who are homeless and have HIV.

As you can see, using The Public Health Approach helps public health professionals identify a problem, find out what is causing it, and determine what solutions/interventions work.

CDC Museum’s Historic Collection has many objects and documents related to early days of work on what we now call HIV/AIDS. The CDC Museum Collections Manager Mary Hilpertshauser (contractor) shares her favorite HIV/AIDS related item in collection – a booklet that was mailed to every U.S. address in 1988 to increase understanding of the disease and to reduce stigma. The “Understanding AIDS” pamphlet made public health history in 1988 because it was mailed to every household in the United States. According to several national polls, approximately 126 million copies were distributed, reaching at least 60 percent of the population.

“Understanding AIDS” was a pioneering effort, as it was the first government publication aimed at the general public that contained all the essential facts about AIDS. It used explicit language to describe HIV Infection and AIDS as pioneered in the “Surgeon General’s Report on Acquired Immune Deficiency Syndrome.” It allowed people to start talking more openly about sex and sexual orientation. Read a CDC Morbidity and Mortality Report article announcing the mailer.

In the image above, Mary displays the mint condition, never-opened booklet safely preserved in the CDC Museum Historic Collection.