How can someone get an HIV test?

People can either voluntarily request an HIV test (voluntary HIV testing) or they may be offered a test by a healthcare provider without asking for it (provider-initiated testing). Provider-initiated testing can happen in a variety of routine care settings, such as pre-natal care, hospitals and doctors’ offices. In the case of an offer of a test, there are two approaches:

• Opt-in testing: a person is offered an HIV test and must actively accept testing before the test can occur.
• Opt-out testing: a person is notified that HIV testing is a part of normal care for everyone but they can decline. If they do not decline, assent to testing is assumed.

Many provinces and territories use both voluntary and provider-initiated approaches, varying the strategy based on the setting and population being served.

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There are two primary approaches to HIV testing: 1) standard HIV testing and 2) rapid point-of-care testing (available in some provinces/territories). To test for HIV, a sample of a person’s blood is taken (either a vial of blood from a vein or a couple of drops of blood from a finger prick). The blood is either sent to a laboratory to be tested for HIV or, with rapid point-of-care testing, the blood is tested immediately for HIV at the location it was taken.

If the blood is sent to a laboratory, the person being tested will have to return for a second visit to the place where they were tested to receive the result.

With point-of-care testing, the person receives the result within a few minutes. The result may be non-reactive (negative) or reactive (probably positive). If the test is non-reactive, no further testing is required; however, if the test is reactive, then a second blood sample is taken and sent to the laboratory for confirmatory testing. The person will have to return for a second visit to receive the final result.

Another testing approach that will soon be available in Canada is HIV self-testing, where a person can collect a sample of their own blood, perform the test and interpret the results. If someone has a reactive (probably positive) test result with a self-test, then they will have to get a standard HIV test so the result can be confirmed by a laboratory. An HIV self-test is currently being researched in Canada and is likely to become available at some point in 2020 for purchase and use.

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HIV testing technologies are used to determine if a person has HIV. Several types of HIV testing technologies are used in Canada. These tests differ in several ways, including how the test detects HIV infection, the length of its window period and how long it takes to receive results.

People can be tested for HIV in a variety of different settings in Canada, including hospitals, health clinics and the community. They also now have the option to test themselves in their own home.

To test for HIV, a sample of a person’s blood is taken. With the most common test, a vial of blood taken from a vein is sent to a laboratory to be tested for HIV (standard testing). There are also rapid tests available, which use a drop of blood from a finger prick to test for HIV immediately after the sample is taken.

Laboratory Testing:

 Most HIV testing of blood samples is conducted in a laboratory. Typically, a blood sample is drawn from a person’s vein and sent to a public health laboratory for analysis. A much less common method of collecting blood samples is through dried blood spot (DBS). This approach uses samples of blood from a finger prick that are collected as blots on a card. The blood spots are dried at room temperature and mailed to a public health laboratory. Currently, this collection technique is in limited use in Canada because very few public health laboratories can process the DBS cards to prepare the blood for analysis. DBS samples are very stable once collected and do not need to be refrigerated, which makes this sampling approach particularly useful in rural and remote areas.

Regardless of how the blood was collected, the first test used in a laboratory to analyze a blood sample is referred to as a screening test. All laboratories in Canada use a fourth-generation test to screen blood samples.

If the screening test indicates that the person who gave the blood sample does not have HIV (also known as a non-reactive test result or testing negative or HIV negative), no further testing is normally performed. The negative result is sent back to the healthcare provider or clinic that ordered the test so that the person who tested can be given the result.

If the screening test indicates that the person may have HIV (also known as a reactive test result), then another test is performed on the same sample to confirm that the result of the screening test was correct. If the confirmatory test indicates that the person is HIV positive, the positive result is sent back to the healthcare provider or clinic that ordered the test so that the person who tested can be given the result.

It can take up to one or two weeks for a person to receive their test result when laboratory testing is conducted.

Rapid Testing:

There are two types of rapid HIV tests in Canada, the point-of care (POC) test and the self-test. Rapid tests are third-generation screening tests. Currently in Canada the POC test and the self-test use the same technology.

Point of Care Testing

Point-of-care tests can provide results within minutes, so the client can be given the result of the test during the same visit. There is only one POC test approved for use in Canada, the INSTI HIV-1/HIV-2 Antibody Test. This test requires a drop of blood from a finger prick to test for HIV.

If the POC test indicates no HIV infection is present (a non-reactive test result), then no further testing is normally performed and the person who tested can be immediately informed of their HIV-negative result. However, if the POC test indicates that a person has HIV (a reactive test result), this is not a final diagnosis. Instead, a vial of blood must be taken and sent to a public health laboratory for confirmatory testing. It can take up to one or two weeks to receive the results from confirmatory testing.

In some cases, if the POC test result is non-reactive and there is reason to believe the person being tested may have recently been exposed to HIV (and is in the window period – see below for more details), a vial of blood can be taken and sent to a laboratory for testing.

Self Testing:

HIV self-tests allow people to test themselves for HIV in their home or other locations and can provide results within minutes. The first HIV self-test was licensed for use and sale in Canada in November 2020. The INSTI HIV Self Test uses the same technology as the POC test and requires a single drop of blood to test for HIV. As with the POC test, if the self-test result is non-reactive then no further testing is required, as long as the person doing the test is out of the window period. A reactive test result requires a confirmatory test and will require the person who uses the self-test to seek out confirmatory testing.

Confirmatory Tests:

The Geenius HIV 1/2 Confirmatory Assay is now used by public health laboratories in Canada and has replaced the Western blot as the standard test used to confirm a reactive HIV screening test.

Other types of confirmatory testing may be used in certain circumstances, such as when a test result is indeterminate. These include nucleic acid amplification tests (NAATs) and p24 antigen-only tests.

No test can detect HIV immediately after infection. The time between when a person is exposed to HIV and when an HIV test can tell they have HIV is called the window period. The window period can vary between two weeks and three months. The length of the window period varies from person to person and also depends on the type of test used. Some people develop markers of HIV infection that are detected by HIV tests slowly and some people develop them more rapidly. Once these markers of HIV infection are present in amounts that the test can detect, the window period is over.

If someone has had a recent exposure to HIV and gets tested for HIV during the window period, the test result may come back as negative (non-reactive) even though the person actually has HIV. This would happen if their body has not started producing the markers of HIV infection at levels that are detectable by the test. When a test result is negative after a recent exposure to HIV, the person should be retested at the end of the window period to confirm they are HIV negative.

The most commonly used HIV tests in Canada detect different markers of HIV infection. Some look for HIV antibodies (proteins produced by the body’s immune system in response to HIV infection) only, while another looks for both antibodies and the p24 antigen (a specific part of the virus itself). All antibody tests in Canada can detect both HIV-1 (the most common type of HIV) and HIV-2.

Rapid HIV screening tests, including both the POC and self-test, are third-generation tests and detect HIV antibodies. The window period for these tests is between three weeks and 12 weeks. These tests can detect HIV antibodies in 50% of people by about 22 days after exposure to HIV and 99% of people by 12 weeks after exposure.

The antibody–antigen combination test is the fourth-generation screening test used in public health laboratories in Canada. This test detects both the p24 antigen and antibodies. The window period for this test is between two weeks and 6.5 weeks. It can detect HIV in 50% of people by 18 days after exposure to HIV and in 99% of people by 44 days after exposure. This means that the fourth-generation test can find an infection at least a week earlier than third-generation POC and self-tests in most people. This is because the p24 antigen is detectable before HIV antibodies. In addition, the fourth-generation test can rule out an HIV infection 5.5 weeks earlier than third-generation tests.

Most people will get an accurate test result with third- or fourth-generation tests three to four weeks after an exposure to HIV. However, not everyone will. It’s important to test again at the end of the window period to rule out an HIV infection.

The Geenius confirmatory assay can detect HIV infection in 50% of people by 33 days after exposure to HIV and in 99% of people by 58 days after exposure.

HIV tests are very accurate. Once confirmatory testing has been performed, the chance of a positive result being false is essentially zero.

Sensitivity and specificity are measures of the accuracy of an HIV test.

Sensitivity is the chance that a positive test result will correctly indicate that a person has HIV. This means that if the person has HIV, the test will detect it. Higher sensitivity means there is a lower chance of a false-negative result (testing negative when actually HIV positive).

Specificity is the chance that a negative test result will correctly indicate that a person does not have HIV. This means that if the person does not have HIV, the test result will be negative. Higher specificity means there is a lower chance of a false-positive result (testing positive when actually HIV negative).

HIV screening tests used in Canada (including third- and fourth-generation tests) all have a sensitivity of up to 99.9%. In other words, if 1,000 HIV-positive people were tested for HIV, 999 would correctly test positive and one would incorrectly test negative. High sensitivity is ideal for a screening test because it effectively rules out people who don’t have HIV (as long as they are outside the window period). Since the vast majority of people who get tested for HIV are actually HIV negative, the chance of a negative result being false is extremely low.

HIV screening tests used in Canada have a slightly lower specificity of up to 99.5%. In other words, if 1,000 HIV-negative people were tested, 995 would correctly test negative and five would incorrectly test positive. Since the specificity is lower, this means there is a higher chance of false positives with the screening tests. This is why all positive screening test results are sent for confirmatory testing with a test that has a very high specificity.

The Geenius assay has a specificity of 100%. This means that the chance of a false-positive result after confirmatory testing is essentially zero.

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Non-identifying information collected when a person has an HIV test may include age, sex, city of residence, name of the diagnosing healthcare provider, country of birth, ethnicity, and information detailing the HIV-related risk factors of the person being tested.

Whether the name of the person being tested is collected is determined by the testing option: nominal (name-based), non-nominal (non-identifying), or anonymous testing. Nominal and non-nominal testing are widely available in Canada. Anonymous HIV testing is available in some, but not all, provinces.

Nominal testing:

Nominal testing, or name-based testing, is available across Canada and often takes place within clinics, offices of healthcare providers and hospitals. When a person has a nominal HIV test, the HIV test is ordered using the person’s name. If the test is positive, the result is reported to public health authorities using the person’s name and the test result is also recorded in the healthcare record of the person being tested

Non-Nominal testing:

Non-nominal, or non-identifying testing, is also available across Canada and often takes place within clinics and offices of healthcare providers. If a person has a non-nominal HIV test, the HIV test is ordered using a code or the person’s initials or an alias (depending on the province/territory), not their full or partial name. If the test is positive, the result is reported to public health using the person’s name in most (but not all) provinces. The test result is also recorded in the healthcare record of the person being tested.

Anonymous testing:

Anonymous HIV testing is available in some provinces and territories, but not all. This form of HIV testing offers the highest degree of confidentiality for the person being tested. The person does not have to give their name and the HIV test is carried out using a code that is not linked to the person’s identity. Anonymous testing usually takes place in specialised clinics or other community-based venues.

In most provinces or territories where anonymous testing is available, if an anonymous HIV test is positive, the testing laboratory notifies public health about the positive test result. The name and contact information for the individual being tested is not shared with public health (as they are not known). The HIV test result is not recorded on the healthcare record of the person being tested.

Yes, a person’s decision to pursue HIV testing and their HIV status are both confidential pieces of information, except in very rare cases. The maintenance of confidentiality is an important consideration for a person who has decided to be tested for HIV. As with all medical information, it is the responsibility of the provider (that is, the tester) to ensure that the confidentiality of the person being tested is maintained.

There are very limited circumstances in which confidentiality may be broken without consent. For example, the law may require your personal information to be released or some information may be required to be released to public health.

HIV testing must only be performed after a person gives consent that is explicit, informed and voluntary.

It is understood in Canada that respecting and protecting people’s rights needs to be central to HIV testing. HIV testing is voluntary in Canada, meaning that a person is free to accept or refuse an HIV test without threat or coercion. Under no circumstances should the person be pressured to receive an HIV test.

A person being tested for HIV must provide informed consent. To be able to provide informed consent, the person must be able to:

1. Understand the advantages and disadvantages of HIV testing;
2. Interpret the meaning of the test results; and,
3. Understand how HIV can be transmitted.

A pre-test discussion should ensure that the person being tested is able to provide informed consent. The Public Health Agency of Canada’s HIV Screening and Testing Guide recommends that verbal informed consent be sufficient, as with other medical tests.

Before and after the test, the care provider should give the person being tested appropriate written or verbal information or counselling about HIV and how it is transmitted.

Pre-test counselling:

Before an HIV test is given, people should receive appropriate information and/or counselling through a pre-test discussion.

During pre-test counselling the person is asked about their knowledge of HIV transmission and prevention and any sexual and/or drug use behaviours that may have put them at risk for HIV. The testing process may also be reviewed, particularly when point-of-care testing is being used and there is a possible need for confirmatory testing. Pre-test counselling may also include a discussion about testing for other sexually transmitted or blood-borne infections, such as chlamydia, gonorrhea, syphilis, and hepatitis C. It may also include a conversation about the person’s post-test support needs (such as risk reduction services, counselling, etc.).

However, because people with many different backgrounds, experiences, history with HIV testing, and risk profiles are tested for HIV, providers offering the HIV test often tailor the pre-test information or counselling they give to meet the context-specific requirements of the individual. For example, in some situations, a provider may offer extensive pre-test counselling, particularly to those individuals who have never tested for HIV. In other situations, a provider may give written information on HIV testing and prevention, particularly for repeat testers. In all cases, the provider must ensure that the person being tested is able to give informed consent.

Post-test counselling:

After a person is tested for HIV, whether the person tests HIV positive or negative, the provider should offer post-test counselling or information. The provider should tailor the approach to meet the context-specific requirements of the individual. If a standard test is used, the person is asked to come back for a second visit to get the result and receive post-test counselling. In a limited number of provinces, this may take place over the phone if the result is HIV negative. If a rapid point-of-care test is used, post-test counselling occurs in the same visit after the negative or reactive result has been given to the person.

The process can vary across the country but, generally speaking, when a test reveals that the individual is HIV positive, the post-test counselling is extensive (and may take place over time, depending on the needs of the person receiving the diagnosis). Typically, a provider gives a person time to absorb the results, discusses the impact of the positive test result, and provides the opportunity for the person to ask questions. Post-test counselling following a positive diagnosis usually includes support and extensive discussion and comprehensive linkage to other services, including HIV care.

If a rapid point-of-care test indicates a reactive result, the person is informed of the result and, after obtaining informed consent, the counsellor draws a blood sample, which is sent to a laboratory for confirmatory testing. The person is given post-test counselling immediately after receiving a reactive result and again when returning to pick up the result of the confirmatory test one to two weeks later.

If a standard test reveals that the individual is HIV negative, the provider explains the result, ensures the person understands the result, and discusses any other questions about HIV testing, transmission, or prevention. They may also discuss the need for further safer sex or harm reduction education or other services, provide referral to other community services as appropriate, and discuss opportunities for other testing, such as sexually transmitted infections (STIs) or hepatitis C, if appropriate.

If a rapid point-of-care test is non-reactive, the person is given the result and post-test counselling as appropriate to their individual needs. This whole process can be completed in one 20-minute visit (although time can vary based on the person’s pre- and post-test counselling needs).

People who test negative but are in the window period, may be advised to test again at an appropriate time to ensure the result is accurate. For those who test HIV negative, but are at continuing high risk for infection, efforts should be made to actively ensure that they are linked to and engaged in enhanced prevention services and risk-reduction counselling. They should also be encouraged to repeat testing as necessary.

After a client receives a positive HIV test result, the result is reported to public health. A positive result initiates a series of processes to support the care of the client, to identify recent partners who may benefit from testing, and to prevent onward transmission.

Public Health notification:

HIV is a reportable, or notifiable, illness in all Canadian provinces and territories except for Quebec¹. This means that when an HIV infection is confirmed by a clinic, doctor or laboratory, it is reported to public health authorities (within their jurisdiction). Each province and territory has public health laws that stipulate specific requirements for reporting HIV diagnoses. HIV is a reportable disease because it is considered to be of significant importance to public health.

The amount of information collected and shared with public health (in the case of HIV-positive test results) varies according to each province or territory. However, all provinces and territories provide non-nominal (non-identifying) data on positive tests to the Public Health Agency of Canada, which facilitates the production of national-level reports on the state of the HIV epidemic in Canada.

Partner notification:

HIV partner notification, or contact tracing, is the practice of identifying, locating and informing someone that a partner they have had sex or used drugs with has been diagnosed with HIV. Contact tracing is meant to encourage the partners to test for HIV to identify new HIV infections as early as possible.

When someone has a confirmed HIV diagnosis, they are asked by the healthcare provider or public health nurse to contact or provide contact information for all their sexual or drug-sharing partners since their last HIV test. If the person chooses to not contact their partners themselves, the healthcare provider or public health nurse attempts to contact the partners and encourage them to test for HIV. All efforts are made to protect their anonymity, such as not providing the name of the person to partners when they are contacted. However, in some circumstances, such as when the person being contacted only has had one sexual partner, it may not be possible to maintain their anonymity.

Many provinces and territories have laws associated with partner notification: some require that partner notification be carried out (British Columbia, Saskatchewan, Manitoba, Prince Edward Island, Nunavut and Northwest Territories). Others allow it to be carried out (Alberta, Ontario, New Brunswick, Nova Scotia and Yukon). Quebec and Newfoundland and Labrador have no specific laws mandating contact tracing, but health officials conduct contact tracing based on available Canadian guidelines.

Linkage to prevention and care:

HIV testing is an important entry point for people into other services, such as HIV care, treatment, and prevention, as well as other services such as harm reduction and housing.

For people who test HIV positive, attempts should be made to ensure they are linked to, engaged in, and retained in HIV care and treatment, as well as to ensure they are linked to information and services related to prevention, to help avoid the onward transmission of HIV.

For people who test HIV negative, but may continue to be at risk of acquiring HIV, attempts should be made to ensure that they are linked to prevention services, such as pre-exposure prophylaxis (PrEP) and risk-reduction counselling, and repeat testing.

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