Breadcrumb
- Home
- Tests, Treatments & Medications
- Medical Tests
- Human Immunodeficiency Virus (HIV) Test
Content Map Terms
Tests, Treatments & Medications Categories
-
Medications
- Immunization, Inactivated influenza
- Anthrax Vaccine
- Diphtheria, Pertussis, and Tetanus Vaccines
- Haemophilus Influenzae Type B (Hib) Vaccine
- Hepatitis A Vaccine
- Hepatitis B Vaccine
- Herpes-Zoster Vaccine for Shingles
- Human Papillomavirus (HPV) Vaccine
- Measles, Mumps, and Rubella Vaccine
- Meningococcal Vaccine
- Pneumococcal Vaccines
- Polio Vaccine
- Rotavirus Vaccine
- Varicella-Zoster Vaccine for Chickenpox
- Weight-Loss Medicines
- Non-Prescription Products for Weight Loss
- Obesity: Should I Take Weight-Loss Medicine?
-
Medical Tests
- Abdominal Ultrasound
- Abdominal X-Ray
- Adrenocorticotropic Hormone
- Alanine Aminotransferase (ALT)
- Albumin Urine Test
- Aldosterone in Blood
- Aldosterone in Urine
- Alkaline Phosphatase
- Allergy Tests
- Alpha-Fetoprotein (AFP) in Blood
- Ambulatory Electrocardiogram
- Ammonia
- Amniocentesis
- Amylase
- Angiogram
- Angiogram of the Head and Neck
- Angiogram of the Lung
- Antinuclear Antibodies (ANA)
- Antisperm Antibody Test
- Antithyroid Antibody Tests
- Arterial Blood Gases
- Arthrogram (Joint X-Ray)
- Arthroscopy
- Aspartate Aminotransferase (AST)
- Autoimmune Disease Tests
- Autopsy
- Barium Enema
- Bilirubin
- Biophysical Profile (BPP)
- Biopsy of Genital Warts
- Bladder Stress Test and Bonney Test for Urinary Incontinence in Women
- Blood Alcohol
- Blood Culture
- Blood Glucose
- Blood Type Test
- Blood Urea Nitrogen
- Body Temperature
- Bone Biopsy
- Bone Density
- Bone Marrow Aspiration and Biopsy
- Bone Scan
- Bowel Transit Time
- Brain Natriuretic Peptide (BNP) Test
- Breast Biopsy
- Breast Cancer (BRCA) Gene Test
- Breast Ultrasound
- Bronchoscopy
- C-Peptide
- C-Reactive Protein (CRP)
- Calcium (Ca) in Blood
- Calcium (Ca) in Urine
- Cancer Antigen 125 (CA-125)
- Carbon Dioxide
- Carbon Monoxide (CO)
- Carcinoembryonic Antigen (CEA)
- Cardiac Blood Pool Scan
- Cardiac Catheterization
- Cardiac Enzyme Studies
- Cardiac Perfusion Scan
- Catecholamines in Blood
- Catecholamines in Urine
- CD4+ Count
- Celiac Disease Antibodies
- Cell-Free Fetal DNA Test
- Chemistry Screen
- Chest X-Ray
- Chlamydia Tests
- Chloride (Cl)
- Cholesterol and Triglycerides Tests
- Chorionic Villus Sampling (CVS)
- Clinical Breast Examination
- Clostridium Difficile Toxins
- Cold Agglutinins
- Colonoscopy
- Colposcopy and Cervical Biopsy
- Complete Blood Count (CBC)
- Computed Tomography (CT) Scan of the Body
- Computed Tomography (CT) Scan of the Head and Face
- Computed Tomography (CT) Scan of the Spine
- Computed Tomography Angiogram
- Contraction Stress Test
- Coombs Antibody Test
- Coronary Calcium Scan
- Cortisol in Blood
- Cortisol in Urine
- Cranial Ultrasound
- Creatine Kinase
- Creatinine and Creatinine Clearance
- Cystometry
- Cystoscopy
- Cystourethrogram
- D-Dimer Test
- D-Xylose Absorption Test
- DHEA-S Test
- Dental X-Rays
- Digital Rectal Examination (DRE)
- Doppler Ultrasound
- Ear Examination
- Echocardiogram
- Electrocardiogram
- Electroencephalogram (EEG)
- Electromyogram (EMG) and Nerve Conduction Studies
- Electronystagmogram (ENG)
- Electrophysiology Study
- Electrophysiology Tests for the Eyes
- Endometrial Biopsy
- Endoscopic Retrograde Cholangiopancreatogram (ERCP)
- Endoscopic Sinus Examination for Sinusitis
- Esophagus Tests
- Evoked Potential Test for Multiple Sclerosis
- Exercise Electrocardiogram
- Extremity X-Ray
- Facial X-Ray
- Ferritin
- Fertility Awareness
- Fetal Blood Sampling (FBS) for Rh Sensitization During Pregnancy
- Fetal Ultrasound
- Folic Acid Test
- Galactosemia Test
- Gallbladder Scan
- Gallium Scan
- Gastrin
- Genetic Test
- Glycohemoglobin
- Gonioscopy
- Gonorrhea Test
- Growth Hormone
- HIV Viral Load Measurement
- Hair Analysis
- Hearing Tests
- Heart Catheterization for Congenital Heart Defects
- Helicobacter Pylori Tests
- Hemochromatosis Gene Test
- Hemoglobin Electrophoresis
- Hepatitis A Virus Test
- Hepatitis B Virus Tests
- Hepatitis C Virus Tests
- Herpes Tests
- High-Sensitivity C-Reactive Protein
- Home Blood Glucose Test
- Home Blood Pressure Test
- Home Ear Examination
- Home Lung Function Test
- Home Pregnancy Tests
- Homocysteine
- Hormone Inhibin A
- Human Chorionic Gonadotropin (HCG)
- Human Immunodeficiency Virus (HIV) Test
- Human Papillomavirus (HPV) Test
- Hysterosalpingogram
- Hysteroscopy
- Immunoglobulins
- Intravenous Pyelogram (IVP)
- Iron (Fe)
- Joint Fluid Analysis
- KOH Preparation
- Karyotype Test
- Ketones
- Kidney Biopsy
- Kidney Scan
- Kidney Stone Analysis
- Lactic Acid Dehydrogenase (LDH)
- Lactic Acid
- Laparoscopy
- Laryngoscopy
- Lead
- Lipase
- Liver Biopsy
- Liver Function Tests
- Liver and Spleen Scan
- Lumbar Puncture
- Lung Biopsy
- Lung Cancer Screening: Low-Dose CT Scan
- Lung Function Tests
- Lung VQ Scan
- Lyme Disease Test
- Lymph Node Biopsy
- Magnesium (Mg)
- Magnetic Resonance Angiogram (MRA)
- Magnetic Resonance Imaging (MRI) of the Abdomen
- Magnetic Resonance Imaging (MRI) of the Breast
- Magnetic Resonance Imaging (MRI) of the Head
- Magnetic Resonance Imaging (MRI) of the Knee
- Magnetic Resonance Imaging (MRI) of the Shoulder
- Magnetic Resonance Imaging (MRI) of the Spine
- Magnetic Resonance Imaging (MRI)
- Mammogram
- Mediastinoscopy
- Medicine Levels in Blood
- Mental Health Assessment
- Mononucleosis Tests
- Myelogram
- Myoglobin
- Needle Puncture and Aspiration of Sinus Contents for Sinusitis
- Neurological Examination for Multiple Sclerosis
- Neuropsychological Tests
- Nuchal Translucency Screening Test
- Ophthalmoscopy
- Oral Glucose Tolerance Test
- Overnight Dexamethasone Suppression Test
- Pap Test
- Paracentesis
- Parathyroid Hormone
- Partial Thromboplastin Time
- Pelvic Examination
- Pelvic Ultrasound
- Pericardial Drainage
- Perimetry Test for Glaucoma
- Phenylketonuria (PKU) Test
- Phosphate in Blood
- Phosphate in Urine
- Positron Emission Tomography (PET)
- Potassium (K) in Blood
- Potassium (K) in Urine
- Prealbumin Blood Test
- Prolactin
- Prostate Biopsy
- Prostate-Specific Antigen (PSA)
- Prothrombin Time and INR
- Pulse Measurement
- Radioactive Iodine Uptake Test
- Rapid Strep Test for Strep Throat
- Renin Assay
- Reticulocyte Count
- Retinal Imaging
- Retrograde Pyelogram for Kidney Stones
- Rheumatoid Factor (RF)
- Rubella Test
- Salivary Gland Scan
- Sedimentation Rate
- Seizure Medicine Levels in Blood
- Self-Examination for Dental Plaque
- Semen Analysis
- Sentinel Lymph Node Biopsy
- Serum Osmolality
- Serum Protein Electrophoresis (SPEP)
- Sickle Cell Test
- Sigmoidoscopy
- Single Photon Emission Computed Tomography (SPECT)
- Skin Biopsy
- Skin and Wound Cultures
- Skull X-Ray
- Sleep Studies
- Slit Lamp Examination
- Sodium (Na) in Blood
- Sodium (Na) in Urine
- Sonohysterogram
- Spinal X-Ray
- Sputum Culture
- Sputum Cytology
- Stool Analysis
- Stool Culture
- Stool Tests for Colorectal Cancer
- Swallowing Study
- Sweat Test
- Syphilis Tests
- Tay-Sachs Test
- Testicular Biopsy
- Testicular Examination and Testicular Self-Examination
- Testicular Scan
- Testicular Ultrasound
- Testosterone
- Tests for Bacterial Vaginosis
- Tests for Erection Problems
- Thick and Thin Blood Smears for Malaria
- Thoracentesis
- Throat Culture
- Thyroid Biopsy
- Thyroid Hormone Tests
- Thyroid Scan
- Thyroid and Parathyroid Ultrasound
- Thyroid-Stimulating Hormone (TSH)
- Tissue Type Test
- Tonometry
- Total Serum Protein
- Toxicology Tests
- Toxoplasmosis Test
- Tuberculin Skin Test
- Tympanocentesis for Ear Infections
- Tympanometry in Ear Infections
- Upper Gastrointestinal (UGI) Series
- Upper Gastrointestinal Endoscopy
- Uric Acid in Blood
- Uric Acid in Urine
- Urine Culture
- Urine Test
- Urodynamic Tests for Urinary Incontinence
- Vaginal Examination for Preterm Labour
- Vaginal Self-Examination (VSE)
- Vaginal Wet Mount
- Viral Tests
- Vision Tests
- Vitamin B12 Test
- Vitamin D Test
-
Surgery
- Achilles Tendon Rupture: Should I Have Surgery?
- ACL Injury: Should I Have Knee Surgery?
- Blood Transfusions: Should I Bank Blood Before Surgery?
- Bunions: Should I Have Surgery?
- Carpal Tunnel Syndrome: Should I Have Surgery?
- Cataracts: Should I Have Surgery?
- Dupuytren's Disease: Should I Have Hand Surgery?
- Ear Problems: Should My Child Be Treated for Fluid Buildup in the Middle Ear?
- Endometriosis: Should I Have a Hysterectomy and Oophorectomy?
- Enlarged Prostate: Should I Have Surgery?
- Gallstones: Should I Have Gallbladder Surgery?
- GERD: Which Treatment Should I Use?
- Hammer, Claw, or Mallet Toe: Should I Have Surgery?
- Coronary Artery Disease: Should I Have Bypass Surgery?
- Hysterectomy: Should I Also Have My Ovaries Removed?
- Inguinal Hernia: Should I Have Surgery Now, or Should I Wait?
- Lumbar Herniated Disc: Should I Have Surgery?
- Lumbar Spinal Stenosis: Should I Have Surgery?
- Meniscus Tear: Should I Have Surgery?
- Nearsightedness: Should I Have Laser Surgery?
- Pelvic Organ Prolapse: Should I Have Surgery?
- Peripheral Arterial Disease: Should I Have Surgery?
- Plantar Fasciitis: Should I Have Surgery for Heel Pain?
- Rotator Cuff Problems: Should I Have Surgery?
- Scoliosis: Should My Child Have Surgery?
- Sinusitis: Should I Have Surgery?
- Sleep Apnea: Should I Have Surgery?
- Stress Incontinence in Women: Should I Have Surgery?
- Tennis Elbow: Should I Have Surgery?
- Temporomandibular Disorder: Should I Have Surgery for Jaw Pain?
- Tonsillitis: Should My Child Have a Tonsillectomy?
- Ulcerative Colitis: Should I Have Surgery?
- Umbilical Hernia: Should I Have Surgery?
- Umbilical Hernia: Should My Child Have Surgery?
- Uterine Fibroids: Should I Have Surgery?
- Varicose Veins: Should I Have a Surgical Procedure?
- Wisdom Teeth: Should I Have My Wisdom Teeth Removed?
-
Treatments
- Bedwetting: Should My Child See a Doctor?
- Complementary Medicine: Should I Use Complementary Medicine?
- Advance Care Planning: Should I Receive CPR and Life Support?
- Advance Care Planning: Should I Stop Treatment That Prolongs My Life?
- Hearing Loss: Should I Get Hearing Aids?
- Atrial Fibrillation: Should I Have Catheter Ablation?
- Hemorrhoids: Which Treatment Should I Use?
- Kidney Failure: What Type of Dialysis Should I Have?
- Low Back Pain: Should I Try Epidural Steroid Shots?
- Obesity: Should I Use a Diet Plan to Lose Weight?
- Testicular Cancer: Which Treatment Should I Have for Stage I Non-Seminoma Testicular Cancer After My Surgery?
- Testicular Cancer: Which Treatment Should I Have for Stage I Seminoma Testicular Cancer After My Surgery?
- Warts: Should I Treat Warts?
- First Aid
British Columbia Specific Information
Human Immunodeficiency Virus (HIV) causes an infection that damages the immune system. The immune system is the part of the body that fights infection and disease. If untreated, HIV infection will lead to a serious disease called Acquired Immunodeficiency Syndrome (AIDS).
For information on HIV infection and care in British Columbia, visit BC Centre for Disease Control and BC Centre for Excellence in HIV/AIDS. For information on HIV drug coverage in B.C., please visit the Ministry of Health BC PharmaCare website.
In B.C. HIV testing guidelines recommend that everyone have an HIV test at least every 5 years. They recommend more frequent testing for people who belong to populations that have a greater chance of having HIV, are pregnant, experience a change in their health that suggests HIV, or if someone requests a test. For information on HIV testing, see HealthLinkBC File #08m HIV and HIV Tests and HealthLinkBC File #38a HIV Testing in Pregnancy.
Test Overview
A human immunodeficiency virus (HIV) test detects HIV antibodies or antigens or the genetic material (DNA or RNA) of HIV in the blood or another type of sample. This determines whether an HIV infection is present (HIV-positive). HIV infects white blood cells called CD4+ cells, which are part of the body's immune system that help fight infections. HIV can progress to acquired immunodeficiency syndrome (AIDS).
After the original infection, it takes about 4 to 12 weeks for HIV antibodies or antigens to appear in the blood. The period between becoming infected with HIV and the point at which antibodies or antigens to HIV can be detected in the blood is called the seroconversion or "window" period. During this period, an HIV-infected person can still spread the disease, even though a test will not detect any antibodies or antigens in his or her blood.
Several tests can find antibodies to or genetic material (RNA) of the HIV virus. These tests include:
- Enzyme-linked immunosorbent assay (ELISA). This test is usually the first one used to detect infection with HIV. If antibodies to HIV are present (positive), the test is usually repeated to confirm the diagnosis. If ELISA is negative, other tests are not usually needed. This test has a low chance of having a false result after the first few weeks that a person is infected.
- Polymerase chain reaction (PCR). This test finds either the RNA of the HIV virus or the HIV DNA in white blood cells infected with the virus. PCR testing is not done as frequently as antibody testing, because it requires technical skill and expensive equipment. This test may be done in the days or weeks after exposure to the virus. Genetic material may be found even if other tests are negative for the virus. The PCR test is very useful to find a very recent infection, determine if an HIV infection is present when antibody test results were uncertain, and screen blood or organs for HIV before donation.
- Indirect fluorescent antibody (IFA). This test detects HIV antibodies using a special fluorescent dye and a microscope. This test may be used to confirm the results of an ELISA test.
- Simple/rapid assays. This test does not require sophisticated equipment to perform and can be used in the laboratory or at the point of care (POC) to screen for HIV antibodies.
If HIV antibodies or antigens are not found, the test may be repeated in a few months.
If you have a positive test result, contact your sex partners to inform them. They may want to be tested. You may be able to get help from your local health unit to do this.
Why It Is Done
A test for the human immunodeficiency virus (HIV) is done to:
- Detect an HIV infection. Testing is often done for people with risk factors for HIV infection and people who have symptoms of an HIV infection.
- Screen blood, blood products, and organ donors to prevent the spread of HIV.
- Screen pregnant women for HIV infection. The Society of Obstetricians and Gynecologists of Canada (SOGC) recommends all pregnant women be screened. Pregnant women who are infected with HIV and receive treatment are less likely to pass the infection on to their babies than are women who do not receive treatment.
- Find out if a baby born to an HIV-positive woman also is infected with HIV. A PCR test is often done in this case because the baby may get antibodies against HIV from the mother and yet not be infected.
This test is not done to determine if a person has AIDS. A diagnosis of AIDS means a person is HIV-positive and other problems are present.
How To Prepare
You do not need to do anything before you have this test.
A test for HIV infection can't be done without your consent. Most doctors offer counseling before and after the test to discuss:
- How the test is done, what the results mean, and any other tests that may be done.
- How the diagnosis of an HIV infection may affect your social, emotional, professional, and financial outlooks.
- The benefits of early diagnosis and treatment.
Before the test, it is important to tell your doctor how and where to contact you when your test results are ready. If your doctor has not contacted you within 1 to 2 weeks of your test, call and ask for your results.
How It Is Done
The health professional drawing blood will:
- Wrap an elastic band around your upper arm to stop the flow of blood. This makes the veins below the band larger so it is easier to put a needle into the vein.
- Clean the needle site with alcohol.
- Put the needle into the vein. More than one needle stick may be needed.
- Attach a tube to the needle to fill it with blood.
- Remove the band from your arm when enough blood is collected.
- Apply a gauze pad or cotton ball over the needle site as the needle is removed.
- Put pressure on the site and then put on a bandage.
How It Feels
You may feel nothing at all from the needle puncture, or you may feel a brief sting or pinch as the needle goes through the skin. Some people feel a stinging pain while the needle is in the vein. But many people do not feel any pain (or have only minor discomfort) once the needle is positioned in the vein. The amount of pain you feel depends on the skill of the health professional drawing the blood, the condition of your veins, and your sensitivity to pain.
Risks
There is very little risk of complications from having blood drawn from a vein.
- You may develop a small bruise at the puncture site. You can reduce the risk of bruising by keeping pressure on the site for several minutes after the needle is withdrawn.
- In rare cases, the vein may become inflamed after the blood sample is taken. This condition is called phlebitis and is usually treated with a warm compress applied several times daily.
Results
A human immunodeficiency virus (HIV) test detects HIV antibodies or antigens, or the genetic material (DNA or RNA) of HIV in blood or another type of sample. ELISA results are usually available in 2 to 4 days. Results of other tests may take longer to be available.
Normal: |
No HIV antibodies or antigens are found. Normal results are called negative. |
If a test is done during the seroconversion period and is negative, repeat testing is needed. Most people have HIV antibodies or antigens within 3 months after becoming infected. If a repeat test is negative, there is no infection. |
|
A PCR test to look for genetic material does not detect any RNA or DNA of HIV. |
|
Uncertain: |
Test results do not clearly show whether a person has an HIV infection. This is usually called an indeterminate result. It may occur before HIV antibodies or antigens develop or when some other type of antibody or antigen is interfering with the results. If this occurs, a PCR test, which detects HIV RNA or DNA, may be done to see if the virus is present. |
A person who still has indeterminate results for 3 months or longer is called "stable indeterminate" and is not considered to be infected with HIV. |
|
Abnormal: |
HIV antibodies or antigens are found. These results are called positive. |
A positive ELISA is repeated using the same blood sample. If two or more ELISA results are positive, they must be confirmed by another test, such as a PCR test. |
|
A PCR test finds genetic material (RNA or DNA) of HIV. |
What Affects the Test
Reasons you may not be able to have the test or why the results may not be helpful include:
- Using corticosteroids.
- Having an antibody test done before a detectable amount of antibodies is present (during the seroconversion period).
- Having an autoimmune disease, leukemia, or syphilis.
- Drinking too much alcohol.
What To Think About
- After initial testing, it is important for your doctor to contact you with the results of your test. Be sure to tell your doctor how and where to contact you. If your doctor has not contacted you within 1 to 2 weeks of your test, call and ask for your results.
- The ELISA is a good screening test, because it is usually positive when an HIV infection is present. But the ELISA test results can indicate HIV is present when it is not (false-positive). So the ELISA alone cannot be used to make a definite diagnosis of HIV infection. No one is considered HIV-positive until he or she has a positive test for HIV DNA or RNA.
- Detecting HIV in a newborn infant is difficult. Until about 18 months of age, even a baby who is not infected may still have HIV antibodies received from his or her HIV-positive mother. A PCR test may be done to see if HIV genetic material (RNA or DNA) is present in the baby.
- To be certain that an HIV infection is not present, a person must test negative for the virus at least 3 months after the last possible exposure to HIV. Testing is often repeated in a few weeks to find out whether a person is infected.
- Home blood test kits are currently not available in Canada.
- A screening test for HIV infection may also be done on urine. Urine testing is rarely done.
- Most provinces and territories require health professionals, clinics, and hospitals to report confirmed cases of HIV infection to the provincial ministry of health. This is often done through anonymous reporting (the person's name or other identifying information is not provided).
- After an HIV infection is present, other tests are done to determine when to treat the infection and how treatment is working. These tests include a CD4+ count and the viral load.
- Two types of HIV have been identified.
- HIV-1 causes almost all of the cases of AIDS worldwide.
- HIV-2 is found mostly in West Africa.
Related Information
References
Other Works Consulted
- Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.
- Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
- U.S. Department of Health and Human Services Panel on Antiretroviral Guidelines for Adults and Adolescents (2015). Guidelines for the use of antiretroviral agents in HIV-1-infected adults and adolescents. U.S. Department of Health and Human Services. http://aidsinfo.nih.gov/contentfiles/lvguidelines/adultandadolescentgl.pdf. Accessed May 5, 2015.
Credits
Adaptation Date: 4/28/2022
Adapted By: HealthLink BC
Adaptation Reviewed By: HealthLink BC
Adaptation Date: 4/28/2022
Adapted By: HealthLink BC
Adaptation Reviewed By: HealthLink BC
This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use and Privacy Policy. Learn how we develop our content.
Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
HealthLinkBC Files
HealthLinkBC Files are easy-to-understand fact sheets on a range of public health and safety topics including disease prevention and immunizations.
Find Services and Resources
If you are looking for health services in your community, you can use the HealthLinkBC Directory to find hospitals, clinics, and other resources.