Ending the HIV/AIDS Syndemic
“Far better is it to dare mighty things, to win glorious triumphs, even though checkered by failure... than to rank with those poor spirits who neither enjoy nor suffer much, because they live in a gray twilight that knows not victory nor defeat.”
During the course of my 43 years as an infectious diseases physician, I’ve witnessed the onslaught of many, if not all, of the more than 140 so-called “emerging infections.” But in terms of its devastation and extraordinary complexity, none of the others comes even close to HIV/AIDS. Thus, in 2019 when organizations such as the World Health Organization, UNAIDS, Center for Disease Control and Prevention, and the administration of President Donald J. Trump announced the goal of ending the HIV/AIDS epidemic by 2030, I was delighted but somewhat skeptical.
Current status of HIV/AIDS. According to UNAIDS, approximately 37.9 million people across the globe were living with HIV/AIDS in 2018. Of these, 36.2 million were adults, and 1.7 million were children (<15 years old). An estimated 1.7 million individuals worldwide became newly infected with HIV in 2018. And of those newly infected, 1.6 million were ages 15 and older, and 160,000 infections were among children ages 0-14. Because HIV infection doesn’t manifest clinically for an average of 10 years after acquiring the virus sexually or via intravenous drug use, many of those infected don’t realize it. Accounting for this huge hidden part of the HIV/AIDS iceberg is crucial in developing mathematical models for predicting the end of HIV/AIDS.
Since the early years of the HIV/AIDS epidemic, when everyone infected was destined to die of it, much has been accomplished, mainly due to the advent in the mid-1990s of highly effective antiretroviral therapy (ART). Currently, there are more than 25 FDA-approved drugs to treat HIV-infected patients. Although none of these medications can totally eradicate the virus, persons with HIV who are treated with ART have a near-normal life expectancy. And importantly, with effective sustained viral suppression, they don’t transmit HIV to sexual partners.
The HIV/AIDS Syndemic. Everybody’s heard of the word epidemic (from the Greek “epi,” upon + “demos,” people or population), but when HIV/AIDS was first recognized in 1981 in gay males and injection drug users in California and New York, it appeared to be an endemic (a disease or social condition found in a specific area or group). When it then quickly spread throughout the rest of the world it took on the characteristics of a pandemic (observed in a wide geographic area or even worldwide). Over the past several decades, however, as the interacting biological and sociological factors involved in HIV/AIDS became more fully understood, it seemed best described as a syndemic.
The term syndemic was coined by Merrill Singer, a medical anthropologist at the University of Connecticut, in the mid-1990s . She used the term to describe the way epidemics can overlap with one another and are fueled by social and cultural problems. By definition, a syndemic is “the aggregation of two or more concurrent or sequential epidemics or disease clusters in a population with biological interactions, which exacerbate the prognosis and burden of disease.”
Syndemics develop under health disparity, caused by poverty, stress, or structural violence. They are primarily studied by professionals interested in public or community health and the effects of social conditions on health. Other syndemics have been subjects of prior Germ Gems blogs (most recently, Hepatitis A Outbreaks and the Social Determinants of Health, January 8, 2020).
The separate epidemics of HIV/AIDS, substance abuse, trauma, incarcerations, racism, and poverty are known to be interconnected and to comprise the syndemic. Surrounding the syndemic are behavioral, social, and structural factors, each of which influence and are influenced by the others.
What’s needed to end the HIV/AIDS syndemic? If a successful vaccine were to come along, this would be a real game changer. In fact, we could in relatively short order declare “game over!” (Of course, a magic wand that put an end to unsafe sex and sharing of needles would be even better.) But in the absence of these preventative measures, the end of the HIV/AIDS syndemic will depend upon both biological and sociological approaches.
The cornerstone of the biological measures is widespread (global) use of ART. To date the most successful and remarkable program is one that made ART readily available in Africa—the United States President’s Emergency Plan for AIDS Relief (PEPFAR). First announced during the 2003 State of the Union Address by the then President, George W. Bush, PEPFAR celebrated its 15th anniversary in 2018. By providing medicines and infrastructure support for ART, PEPFAR has saved millions of lives, prevented millions of new infections, and changed the course of the epidemic.
In his 2019 Sate of the Union Address, President Donald Trump announced another program, “Ending the HIV Epidemic: A Plan for America.” This ten-year initiative aims to reduce new HIV infections to less that 3,000 per year by 2030. (This would signify that the epidemic had ended statistically in America.) To achieve this ambitious goal, it will be necessary to implement ART in a large majority of infected individuals. Key to its success is the “Ready, Set, PrEp Program” led by the U.S. Department of Health and Human Services, which makes ART available at no cost to thousands of people who qualify. PrEP stands for “Pre-Exposure Prophylaxis, “ and it's the use of anti-HIV medication that keeps HIV negative people from becoming infected. PrEP is approved by the FDA and has been shown to be safe and effective.
Even if this aspirational goal is achieved and HIV transmissions no longer occur in epidemic proportions in the U.S., it would not be possible to declare an end to HIV. There will still be at least 1 million people in the United States living with HIV, and it will be important to attend to their special medical needs even though they may have suppression of the virus to below detectable levels.
Persons with HIV have a disproportionate risk of various comorbidities, such as cardiovascular disease, chronic kidney disease, osteopenia, osteoporosis, hepatic disease, and cancer, as well as a significant burden of neurocognitive disorders. Unless a cure is developed for HIV, which would entail eradication of the replication-competent viral reservoir, persons with HIV will contend with this heightened risk of HIV-associated comorbidities.
Of course, biological programs like PrEP won’t eliminate any of the social determinants that play key roles in the HIV/AIDS syndemic, such as injection drug use, racism, and poverty. But then again, the quotation cited at the beginning of this post by the 26th President of the U.S. and winner of the 1906 Nobel Peace Prize, Theodore Roosevelt, was uttered 18 years before the opening of the Panama Canal—an unfathomable achievement that he helped realize.