The Big Picture
Your immune system helps protect your body from things that might harm it. An immune system disorder happens when this protective response does not work as it should. The response might be too strong, too weak, or inappropriate.
HIV attacks the immune system and weakens its ability to fight certain infections. Untreated HIV might progress to AIDS. Autoimmune disorders work differently. With an autoimmune disorder, the immune system attacks the body’s own healthy cells, tissues, or organs.
Look for Nova Scotia CCA Notes throughout this page for current provincial guidance.
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Start Here If You’re Overwhelmed
Focus on these core ideas:
- human immunodeficiency virus (HIV) attacks the immune system and weakens its ability to fight certain infections.
- acquired immune deficiency syndrome (AIDS) is HIV infection that has progressed, usually after going untreated.
- HIV spreads when certain infected body fluids enter another person’s body.
- A person with HIV might have no symptoms for years and still pass the virus to someone else.
- People who start antiviral treatment early can live a longer and healthier life.
- Autoimmune disorders happen when the immune system attacks the body’s own healthy cells, tissues, or organs.
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Course Notes: Key Ideas You Need to Know
How Immune System Disorders Happen
The immune system protects the body from pathogens, cancer cells, and other harmful substances. Immune system disorders develop when the immune response becomes impaired .
The response might be inappropriate, unusually strong, or lacking. HIV and autoimmune disorders are two types discussed here.
What HIV Is
human immunodeficiency virus (HIV) is a viral infection that attacks the immune system. This makes it harder for the body to fight certain infections.
A person infected with HIV is described as HIV-positive. Without treatment, HIV might progress to acquired immune deficiency syndrome (AIDS).
Antiviral medication regimens help people living with HIV or AIDS live for years or even decades. Some people may also develop other health conditions that may be unrelated to HIV or AIDS.
HIV Treatment and Progression
Without treatment, an HIV-positive person might develop AIDS within 5 to 10 years.
Starting antiviral treatment early supports a longer and healthier life. A person receiving treatment who has no active virus detected in their body can also prevent sexual transmission of HIV to partners.
How HIV Spreads
HIV does not spread only through sexual contact. People of any age might acquire HIV through sexual or non-sexual transmission.
HIV spreads when infected body fluid from a person with HIV enters another person’s body. Supported examples of these fluids include:
- blood
- semen and pre-seminal fluid
- fluid from the rectum
- vaginal fluid
The infected fluid might enter through broken skin or through mucous membrane linings. Examples include the vagina, rectum, foreskin, and opening of the penis.
HIV also spreads through shared drug-use equipment, including needles, syringes, and other equipment used to inject drugs.
An HIV-positive child-bearing person might also pass HIV to their baby during:
- pregnancy
- childbirth
- breastfeeding
Early HIV Symptoms
Some people have no symptoms immediately after infection. Others develop mild flu-like symptoms about 2 to 4 weeks after infection.
During the first few weeks, some tests might not detect the virus. Some people have HIV for as long as 10 years without experiencing symptoms.
Early symptoms might last several days or several weeks and then seem to disappear. A person who is HIV-positive might still transmit HIV during this time.
Common early symptoms include:
- fever
- fatigue
- chills
- sore throat
- headache
- muscle aches
- joint pain
- swollen glands, called lymph nodes
These early symptoms may be mistaken for other illnesses.
Testing and Follow-Up
A person who thinks they have symptoms of HIV or AIDS needs to see a health care provider for testing and counselling.
If testing confirms HIV, treatment should begin as soon as possible. The person should also notify sexually intimate partners and people with whom they shared drug-use equipment.
Nova Scotia CCA Note
Sorrentino’s Canadian Textbook for the Support Worker, 5th Edition says treatment can prevent sexual transmission when no active virus is detected. Current Nova Scotia guidance uses the term undetectable equals untransmittable (U=U). A person living with HIV who takes antiretroviral therapy (ART) and maintains an undetectable viral load has effectively no risk of transmitting HIV through sexual contact. Nova Scotia does not extend U=U to breastfeeding/chestfeeding or injection drug use because there is not enough evidence to say there is no risk in those situations. (novascotia.ca)
Nova Scotia also changed its HIV reporting rules effective June 1, 2025. HIV and AIDS remain reportable to Public Health. Partner notification follows Public Health guidance. Usually, the person living with HIV notifies contacts, but notification can be handled by a physician or public health nurse in some situations, including when safety is a concern. (novascotia.ca)
Why this matters in Nova Scotia: Students should recognize U=U as current provincial terminology and understand that partner notification follows Nova Scotia Public Health guidance.
Official source: Nova Scotia Communicable Diseases Manual: General Information: HIV (June 2025)
Last checked: October 2, 2026
What AIDS Is
acquired immune deficiency syndrome (AIDS) is HIV infection that has progressed, usually because the HIV infection went untreated.
Starting HIV treatment early can help a person with HIV live a near-normal lifespan.
Symptoms of AIDS include certain types of:
- pneumonia
- cancerous skin tumours
- fungal infections, including yeast infections
- viral infections, including shingles
- long-term diarrhea
- rapid, unexplained weight loss
Supporting a Client Living With HIV or AIDS
Listen and Offer Support
An HIV diagnosis changes a person’s life. Listen to the client, offer support, and reassure them that HIV is a manageable health condition.
Support the Medication Routine
Encourage the client to follow their medication regimen .
People living with HIV need to take their HIV medication every day, exactly as prescribed. Work with the client and their significant others to help establish a regular medication routine and encourage the client to continue it.
Encourage Healthy Practices
Support the client in choosing nutrient-rich foods that follow Canada’s Food Guide recommendations.
The supported healthy practices also include:
- reducing alcohol intake
- getting enough sleep
- exercising
- avoiding recreational drugs without the health care provider’s consent
- practising safer sex
Watch for Illness
People living with HIV might have less resistance to illnesses such as colds and influenza.
Observe for signs of illness. Encourage the client to seek early treatment when they feel unwell.
Encourage Support and Education
Support groups and counselling can be valuable sources of information and support for clients and significant others. Groups also help clients think about what to say to intimate partners who do not know about the diagnosis.
Encourage clients and families to learn about HIV medications, signs of illness, and ways to stay healthy. This knowledge can give the client a sense of empowerment .
What Autoimmune Disorders Are
Autoimmune disorders happen when the immune system attacks the body’s own healthy cells, tissues, or organs.
They might affect any part of the body. They often affect several body parts at the same time. They might change how an organ works or cause abnormal organ growth.
Examples discussed here include:
- multiple sclerosis
- rheumatoid arthritis
- scleroderma
- type 1 diabetes
- celiac disease
- inflammatory bowel disease, including Crohn’s disease, colitis, and irritable bowel syndrome (IBS)
Important Autoimmune Disorder Terms
multiple sclerosis (MS) is a persistent, slowly progressing disease. The immune system attacks the protective myelin sheaths around nerve cells in the brain and spinal cord. This process is called demyelination. Damaged areas then fail to transmit nerve impulses normally.
scleroderma is a progressive autoimmune disease involving hardening of the skin and connective tissue throughout the body.
celiac disease is an inborn metabolic disorder involving an inability to tolerate gluten protein found in wheat, oats, and barley.
Crohn’s disease is a persistent inflammatory bowel disease of unknown origin. It usually affects the ileum, colon, or another part of the gastrointestinal tract.
colitis means inflammation of the colon.
irritable bowel syndrome (IBS) is a bowel disorder involving abdominal pain and changes in bowel habits.
Hashimoto’s Disease
Hashimoto’s disease affects the thyroid gland.
Antibodies react against proteins in the thyroid. Over time, this gradually destroys the gland. Eventually, the thyroid does not produce enough thyroid hormone.
Supported signs and symptoms include:
- fatigue
- weakness
- weight gain
- sensitivity to cold
- muscle aches
- stiff joints
- facial swelling
- constipation
Graves’ Disease
With Graves’ disease, antibodies react with a receptor on the thyroid gland. This might cause the gland to produce too much thyroid hormone and lead to a hyperthyroid condition.
Supported signs and symptoms include:
- anxiety
- trouble sleeping
- rapid heart rate
- weight loss
- sweating
- muscle weakness
- shaky hands
- bulging eyes
Lupus
Lupus is an inflammatory disease that affects several parts of the body. It might damage the joints, skin, kidneys, heart, lungs, and other body parts.
A butterfly-shaped rash across the nose and cheeks is common. Lupus is sometimes difficult to diagnose because symptoms vary and might resemble other illnesses.
A person with lupus might move between periods of illness and periods of remission. Some people with lupus are able to live normal lives, while others may be very sick.
CCA action: When caring for a client with lupus, follow the care plan carefully because treatment differs from one client to another.
Exam Clue Words
- Every day: HIV medication should be taken daily as part of the prescribed medication regimen.
- Exactly as prescribed: The prescribed HIV medication directions matter. The client should follow them exactly.
- Early: Starting HIV treatment early supports a longer and healthier life.
- Follow the care plan: Care for a client with lupus should follow the individual client’s care plan carefully because treatment differs between clients.
Common Mix-Ups
| Wrong Idea | Better Idea |
|---|---|
| HIV spreads only through sexual contact. | HIV can also spread non-sexually through shared drug-use equipment and during pregnancy, childbirth, or breastfeeding. |
Fast Review
Use these points for a fast final review. Focus on the differences, transmission routes, timing, symptoms, and client-support points.
- HIV attacks the immune system and weakens its ability to fight certain infections.
- Untreated HIV might progress to AIDS. Without treatment, this might happen within 5 to 10 years.
- HIV spreads when certain infected body fluids enter another person’s body.
- HIV also spreads through shared drug-use equipment and from an HIV-positive child-bearing person during pregnancy, childbirth, or breastfeeding.
- Mild flu-like symptoms might appear 2 to 4 weeks after HIV infection, but some people have no symptoms for as long as 10 years.
- A person who has no symptoms might still transmit HIV.
- HIV medication should be taken every day, exactly as prescribed.
- AIDS is HIV infection that has progressed, usually because the HIV infection went untreated.
- Autoimmune disorders happen when the immune system attacks healthy cells, tissues, or organs.
- Hashimoto’s disease gradually damages the thyroid gland, while Graves’ disease might cause the thyroid to produce too much thyroid hormone.
- Lupus might affect several body parts and might alternate between periods of illness and remission.
- When caring for a client with lupus, follow the care plan carefully because treatment differs between clients.
Final Pep Talk
This topic has several ideas that sound similar, especially HIV versus AIDS and the different autoimmune disorders. Review them in small groups, then come back to the symptom lists and timing details that need another pass.