Difficulty: Intermediate-Advanced | Prerequisites: Immune system basics (Ch. 4, pp. 97-103), biopsychosocial model, stress and coping.
HIV/AIDS sits at the intersection of immunology, psychology, and social justice. This chapter draws on psychoneuroimmunology (PNI) to explain how stress, personality, and social support affect disease progression, and it examines the cultural, racial, and socioeconomic disparities that shape who gets infected, who gets treated, and who survives. You need the immune system basics from Chapter 4 (pp. 97-103) and a working knowledge of stress models before coming in. The central lesson is that HIV/AIDS is as much a psychological and social condition as it is a biomedical one.
HIV is the virus that causes AIDS; a person can be HIV-positive for 7 to 11 years before progressing. Transmission occurs through blood, semen, vaginal fluids, and breast milk, and an undetectable viral load makes transmission virtually impossible. Treatment (HAART) stops the virus replicating, but only 4 in 10 people globally have access. Women, people of colour, youth, and low-SES groups are disproportionately affected, and stigma remains a major barrier to testing, treatment, and quality of life.
HIV (Human Immunodeficiency Virus)
The virus that causes AIDS. A person can live HIV-positive for an average of 7 to 11 years before progressing to AIDS.
AIDS (Acquired Immunodeficiency Syndrome)
Defined as being HIV-positive and either having at least one of the 21 AIDS-defining opportunistic infections, or a CD4 cell count of 200 or less (normal range: 600-1500).
Psychoneuroimmunology (PNI)
A field studying the interplay between the nervous system, endocrine system, immune system, and psychological activity. In simple terms, it is the science of how your mind affects your immune system.
CD4 cells (T cells)
Immune cells targeted by HIV. Normal count is 600-1500; a count below 200 is one criterion for an AIDS diagnosis.
HAART (Highly Active Antiretroviral Therapy)
A cocktail of different drugs aimed at stopping HIV from replicating. Think of it as: the combination treatment that keeps the virus in check.
PrEP (Pre-Exposure Prophylaxis)
Medication taken by HIV-negative people at high risk of exposure. Two medications that reduce the risk of infection by up to 92%.
PEP (Post-Exposure Prophylaxis)
Emergency medication taken within 72 hours of potential HIV exposure. Highly effective but cannot be used regularly.
HAND (HIV-Associated Neurocognitive Disorder)
A spectrum of cognitive impairments associated with HIV, ranging from Asymptomatic Neurocognitive Impairment (ANI) to Mild Neurocognitive Disorder (MND) to HIV-Associated Dementia (HAD, rare).
Encephalopathy
Gradual loss of cognitive function in HIV/AIDS patients, leaving them confused and disoriented, potentially progressing to coma.
Undetectable viral load
When antiretroviral therapy reduces the amount of HIV in the blood to levels too low to measure. A person with an undetectable viral load has a virtually impossible chance of transmitting HIV to sexual partners.
Evolved from the intersection of biology and psychology.
Studies the interplay between the nervous system, endocrine system, immune system, and psychological activity/behaviour.
Research has found that stress management can slow disease progression in people with HIV/AIDS.
HIV is the virus; AIDS is the syndrome that develops when the immune system is severely compromised.
A person can be HIV-positive for an average of 7-11 years before progressing to AIDS.
AIDS is defined as being HIV-positive and having at least one of 21 AIDS-defining opportunistic infections, or a CD4 count of 200 or less.
Scientists traced the disease to the late 1970s; HIV was named in 1984.
Initially labelled a "gay man's disease" because it was first identified among gay men. Eventually found in heterosexual women and children in Africa.
Because early cases involved a highly marginalised group, funding and attention were slow.
Global numbers have grown 24% since 2001. About 1.1 million Americans have HIV/AIDS (highest in the South, lowest in the Midwest).
Viral loads are highest in blood, followed by semen, vaginal fluids, and breast milk.
Most common spread: unprotected sexual contact, direct blood contact, blood transfusions.
An individual with an undetectable viral load has a virtually impossible chance of transmitting to sexual partners (achieved through antiretroviral therapy).
PrEP: For HIV-negative people at high risk. Two medications; reduces risk by up to 92%.
PEP: Emergency use within 72 hours of exposure. Highly effective but not for regular use.
HIV/AIDS is a major stressor: disclosing status, navigating stigma, managing healthcare all affect mental health.
People living with HIV have 2x the risk for depression.
Cognitive changes can occur: HAND ranges from asymptomatic impairment (ANI) to mild disorder (MND) to dementia (HAD, rare). Encephalopathy involves gradual loss of cognitive function.
Depression is associated with poorer immune function and lower quality of life. Optimism is associated with the opposite.
Personality factors that help: social support, openness, extroversion, conscientiousness.
Resilience factors: social support, access to care and treatment.
HAART is a cocktail of drugs that stops the virus from replicating.
Only 4 in 10 people living with HIV globally have access to treatment.
Most people with AIDS die from tuberculosis, not from the virus itself.
Low CD4 cells and higher-than-average CD8 cells are characteristic.
Women account for about 50% of HIV infections worldwide. The virus is more easily passed to women, and low-income women and women of colour are disproportionately affected.
Latina and African American women account for 73% of women diagnosed in the US.
African American women tend to be with men who are less likely to disclose same-sex behaviours.
Men with HIV tend to be European American, economically advantaged, and better educated.
Youth made up 21% of new cases in 2017. Young males: primarily same-sex transmission. Young females: primarily heterosexual transmission. This age group is the least likely to be virally suppressed and the least likely to be aware of their infection.
College students face particular risks: inadequate sex education, low testing rates, substance use, low condom usage, stigma, and misconceptions about HIV/AIDS.
Stigma and violence toward people with HIV/AIDS persist due to misconceptions.
Students sometimes think HIV and AIDS are the same thing. HIV is the virus; AIDS is the syndrome that develops after prolonged immune suppression (defined by CD4 count or opportunistic infections).
Students may believe that a person with HIV will inevitably transmit it to sexual partners. A person with an undetectable viral load has a virtually impossible chance of transmission.
Students often assume PrEP is a vaccine. It is not: PrEP is a daily medication that reduces risk by up to 92%, taken by people who are HIV-negative but at high risk.
Students sometimes think HIV/AIDS primarily affects gay men. Women account for about 50% of global infections, and the demographics vary considerably by region and race.
⚠️ Know the difference between HIV and AIDS, including the specific CD4 count threshold (200 or less) and the 21 opportunistic infections criterion.
⚠️ PrEP vs. PEP: know which is preventive (before exposure) and which is emergency (within 72 hours).
⚠️ Undetectable = untransmittable is a key concept.
⚠️ Know what PNI is and how it connects mind, immune system, and disease progression.
⚠️ HAND and its subtypes (ANI, MND, HAD) are likely testable.
⚠️ Cultural demographics: women = 50% of global infections; Latina + AA women = 73% of US women diagnosed; youth = 21% of new cases.
⚠️ Only 4 in 10 people living with HIV globally have access to treatment.
Fill in the blank: A CD4 count of ________ or less is one criterion for an AIDS diagnosis. (200.)
True or False: PEP must be taken within 48 hours of exposure. (False: within 72 hours.)
Fill in the blank: PrEP reduces the risk of HIV infection by up to ________%. (92%.)
True or False: Most people with AIDS die from HIV itself. (False: most die from tuberculosis.)
True or False: A person with an undetectable viral load can still easily transmit HIV. (False: transmission is virtually impossible.)
Q: What is psychoneuroimmunology, and how does it apply to HIV/AIDS?
A: PNI is the study of how the nervous, endocrine, and immune systems interact with psychological activity and behaviour. In HIV/AIDS, PNI research shows that stress management can slow disease progression, while depression worsens immune function and quality of life.
Q: A college student says they do not need to worry about HIV because it is a "gay man's disease." How would you correct this using course material?
A: HIV affects all demographics. Women account for 50% of global infections, and among US women, Latina and African American women make up 73% of diagnoses. Among youth, young females are infected primarily through heterosexual contact. College students specifically face elevated risks from low testing rates, inadequate sex education, and substance use.
Q: What is the difference between PrEP and PEP?
A: PrEP is a preventive medication taken daily by HIV-negative people at high risk, reducing infection risk by up to 92%. PEP is an emergency medication taken within 72 hours after potential exposure; it is highly effective but not intended for regular use.
Q: Describe the spectrum of HIV-associated neurocognitive disorders (HAND).
A: HAND ranges from Asymptomatic Neurocognitive Impairment (ANI, no obvious symptoms but measurable on testing), through Mild Neurocognitive Disorder (MND, noticeable cognitive difficulties), to HIV-Associated Dementia (HAD, rare, severe cognitive decline). Separately, encephalopathy involves a gradual loss of cognitive function that can progress to coma.
PNI is the theoretical bridge between this chapter and every other chronic-disease chapter in the course: the stress-immune pathway explains how psychological factors affect cancer progression (Ch. 13) and heart disease (Ch. 14). Cultural disparities in HIV/AIDS mirror the patterns seen in patient-provider communication (Ch. 9) and cancer screening. The role of social support and personality in disease outcomes connects to the broader exam themes of the biopsychosocial model and social determinants of health.
HIV, AIDS, Human Immunodeficiency Virus, Acquired Immunodeficiency Syndrome, psychoneuroimmunology, PNI, CD4 cells, T cells, CD8 cells, HAART, antiretroviral therapy, PrEP, pre-exposure prophylaxis, PEP, post-exposure prophylaxis, undetectable viral load, HAND, neurocognitive disorder, ANI, MND, HAD, encephalopathy, opportunistic infections, tuberculosis, HIV stigma, HIV transmission, HIV and women, HIV and youth, college students and HIV, HIV cultural variations