HIV is the virus that causes AIDS; a person can be HIV-positive for 7 to 11 years before developing AIDS. Psychoneuroimmunology (PNI) explains how stress management affects disease progression. Prevention tools include PrEP and PEP, and treatment centres on HAART. Cultural disparities are stark: women, people of colour, youth, and low-SES groups are disproportionately affected.
Difficulty: Intermediate | Prerequisites: Basic immune system concepts (Ch. 4, pp. 97-103), biopsychosocial model
This chapter bridges immunology and psychology through the lens of HIV/AIDS. It begins with psychoneuroimmunology, which studies how the mind interacts with the immune system, then covers the biology of HIV and AIDS, transmission routes, prevention, treatment, and the psychological burden of living with the disease. Cultural disparities are a central theme: who is at risk, who has access to treatment, and how stigma shapes outcomes. You should be comfortable with basic immune system function (CD4 cells, opportunistic infections) before starting.
Psychoneuroimmunology (PNI)
The field studying the interplay between the nervous system, endocrine system, immune system, and psychological activity and behaviour. In simple terms, how your mind affects your immune system and vice versa.
HIV (Human Immunodeficiency Virus)
The virus that causes AIDS. A person can be HIV-positive for an average of 7 to 11 years before developing AIDS.
AIDS (Acquired Immunodeficiency Syndrome)
Defined as being HIV-positive and having at least one of the 21 AIDS-defining opportunistic infections, or having a CD4 cell count of 200 or less. Think of it as the stage where the immune system is too damaged to fight off infections that a healthy body handles routinely.
CD4 cells (T cells)
Immune cells targeted by HIV. Normal range is 600 to 1,500. A count of 200 or below is one criterion for an AIDS diagnosis.
Opportunistic infections
Infections caused by organisms that a healthy immune system regularly fights off, but that a compromised immune system cannot. These define the clinical progression from HIV to AIDS.
HAART (Highly Active Antiretroviral Therapy)
A cocktail of different drugs aimed at stopping HIV from replicating. The standard treatment for HIV/AIDS.
PrEP (Pre-Exposure Prophylaxis)
Two medications taken by HIV-negative people at high risk of exposure. Reduces risk by up to 92%. Think of it as a preventive shield for people in high-risk situations.
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 impairment ranging from Asymptomatic Neurocognitive Impairment (ANI) to Mild Neurocognitive Disorder (MND) to HIV-Associated Dementia (HAD, which is rare).
Encephalopathy
Gradual loss of cognitive function that can leave patients confused and disoriented, eventually progressing to a coma. A severe neurological complication of HIV/AIDS.
Psychoneuroimmunology evolved out of biology and psychology. It focuses on the interplay between the mind and the immune system, examining interactions among the nervous system, endocrine system, immune system, and psychological activity. Research in PNI has shown that stress management can directly impact disease progression in people with HIV/AIDS.
Scientists traced the disease back to the late 1970s. HIV was named in 1984.
Initially labelled the "gay man's disease" because it was first identified among gay men.
Eventually found in heterosexual women and children in Africa.
Because it affected a highly marginalised group and was classified as an STD, funding and research efforts were slow.
The global number of cases has grown 24% since 2001. About 1.1 million Americans have HIV/AIDS, with the highest rates in the South and lowest in the Midwest.
Viral loads are highest in blood, then semen, vaginal fluids, and breast milk. The most common routes of spread are unprotected sexual contact, direct blood contact, and blood transfusions.
A person with an undetectable viral load (achieved through antiretroviral therapy) has a virtually zero chance of transmitting HIV to sexual partners.
PrEP: Two medications for HIV-negative people at high risk. Reduces risk by up to 92%.
PEP: Emergency medication taken within 72 hours of potential exposure. Highly effective but not for regular use.
HAART: A cocktail of drugs that stop HIV from replicating. The standard of care.
Only 4 in 10 people living with HIV globally have access to treatment.
Most people with AIDS die from tuberculosis, not from HIV directly.
Living with HIV/AIDS is a major stressor. Disclosing one's status, navigating stigma, and dealing with the healthcare system all take a psychological toll. People with HIV/AIDS have 2x the risk of depression compared to the general population.
Depression is associated with poorer immune function and lower quality of life.
Optimism is associated with the opposite: better immune function and higher quality of life.
Social support, openness, extroversion, and conscientiousness are all protective against disease progression.
HAND covers a spectrum from asymptomatic impairment (ANI) to mild neurocognitive disorder (MND) to the rare HIV-associated dementia (HAD).
Encephalopathy involves gradual loss of cognitive function, leaving patients confused and disoriented, and can progress to a coma.
Social support and access to care and treatment are the primary resiliency factors. People with low CD4 counts and higher-than-average CD8 counts show a particular immune profile.
Stigma and violence towards people with HIV/AIDS persist, largely driven by misconceptions about transmission and the populations most affected.
Women account for about 50% of HIV infections worldwide.
HIV is more easily passed to women. Those affected are more likely to be low-income women and women of colour.
Latina and African American women account for 73% of women diagnosed with HIV/AIDS.
African American women are more likely to be with male partners who do not disclose same-sex behaviours.
Men with HIV/AIDS in the US tend to be European American, economically advantaged, better educated, and without dependants.
Youth accounted for 21% of new HIV/AIDS cases in 2017.
Males: primarily same-sex transmission. Females: primarily heterosexual transmission.
Youth are the least likely age group to be virally suppressed and the least likely to be aware of their infection.
Inadequate sex education, low rates of testing, substance use and abuse, low condom usage, stigma, and misconceptions about HIV/AIDS all contribute to risk. College students have high rates of STDs, feelings of isolation, and low rates of PrEP use.
Students sometimes confuse HIV and AIDS. HIV is the virus; AIDS is the syndrome that develops when the immune system is sufficiently damaged (CD4 count below 200 or presence of an opportunistic infection).
PrEP and PEP are frequently mixed up. PrEP is preventive (taken before exposure, ongoing). PEP is emergency (taken within 72 hours after exposure, short course).
Many students assume HIV is equally transmissible in all bodily fluids. Viral loads are highest in blood, then semen, then vaginal fluids, then breast milk. Casual contact does not transmit HIV.
The idea that HIV is a "death sentence" is outdated. With HAART, people can live with an undetectable viral load and have a near-normal life expectancy.
⚠️ Know the distinction between HIV and AIDS, including the CD4 count threshold (200) and what opportunistic infections are.
⚠️ PrEP vs. PEP: know the difference, who uses each, and the 92% risk-reduction figure for PrEP.
⚠️ The 73% statistic (Latina and African American women's share of female diagnoses) is likely exam material.
⚠️ Know what HAART is and the access gap (4 in 10 globally).
⚠️ HAND and its three levels (ANI, MND, HAD) are testable.
⚠️ Understand PNI and how it connects stress management to disease progression.
True or False: A CD4 count of 300 meets the criteria for an AIDS diagnosis. (False. The threshold is 200 or below.)
Fill in the blank: PrEP reduces the risk of HIV infection by up to ___%. (92)
True or False: A person with an undetectable viral load can still easily transmit HIV to sexual partners. (False. The chance is virtually zero.)
Fill in the blank: _______ is the field studying the interplay between the mind and the immune system. (Psychoneuroimmunology / PNI)
True or False: Most people with AIDS die directly from the HIV virus itself. (False. Most die from tuberculosis or other opportunistic infections.)
Q: What is the difference between PrEP and PEP?
A: PrEP is taken by HIV-negative people at high risk before potential exposure (ongoing, reduces risk by up to 92%). PEP is taken within 72 hours after potential exposure as an emergency measure and cannot be used regularly.
Q: What does HAART stand for, and what does it do?
A: Highly Active Antiretroviral Therapy. It is a cocktail of drugs aimed at stopping HIV from replicating.
Q: Why are women disproportionately affected by HIV/AIDS?
A: HIV is more easily transmitted to women. Those affected are more likely to be low-income women and women of colour. Latina and African American women account for 73% of women diagnosed.
Q: Name the three levels of HIV-Associated Neurocognitive Disorder (HAND).
A: Asymptomatic Neurocognitive Impairment (ANI), Mild Neurocognitive Disorder (MND), and HIV-Associated Dementia (HAD, which is rare).
Q: How does psychoneuroimmunology (PNI) relate to HIV/AIDS?
A: PNI research shows that stress management can directly impact disease progression in people with HIV/AIDS, because the nervous, endocrine, and immune systems interact with psychological states and behaviour.
PNI connects directly to the Cancer chapter (Ch. 13), where stress and NK cells follow a similar logic. The cultural disparities in HIV/AIDS mirror patterns in every other chapter: SES, race/ethnicity, and gender all shape who gets sick and who gets care. Stigma as a barrier to health links to the Patient-Provider Communication chapter (Ch. 9) and the broad exam theme of social determinants of health.
HIV, AIDS, Human Immunodeficiency Virus, psychoneuroimmunology, PNI, CD4 cells, T cells, opportunistic infections, HAART, antiretroviral therapy, PrEP, PEP, HAND, encephalopathy, viral load, undetectable, HIV transmission, HIV stigma, HIV cultural variations, women and HIV, youth and HIV, college students HIV, PSY 320, health psychology