The Role of Infectious Disease Tests
Infectious disease tests are used to diagnose specific diseases. Tests may be administered as a part of a routine health screening or if you are experiencing specific signs or symptoms.
Who should get testing?
You should get tested for an infectious disease if you suspect you may have been exposed to one, particularly if the disease is known to have serious potential complications. Even though you may be asymptomatic or experiencing only mild symptoms, you may still be able to spread the infection to those around you. Some infectious diseases can lead to serious health complications or even death, particularly for those who are immunocompromised.
The goal of screening for infectious diseases is to identify and treat people with infections before they develop complications and before they spread disease to others. Additionally, screening attempts to identify, test, and treat those who have been in contact with you in order to prevent continued spread of the infection.
Types of Infectious Disease Tests
While there are many different kinds of infectious diseases, there are two main ways of detecting whether or not the infection is or was present in your body – looking for antibodies against the infectious agent or looking for the infectious agent (antigen) itself. Serological testing looks for antibodies, your body’s reaction to an infection, in order to verify previous exposure. Polymerase chain reaction (PCR) testing (also called NAAT for nucleic acid amplification testing) is a highly specific test that detects the presence of the infectious agent’s unique genetic material (DNA or RNA).
Testing may involve physical exams, oral swabs, urine tests, pap tests, and microscopic examination of fluid swabbed from a sore, the genitals, or the anus. Other infections are diagnosed through blood tests. Here are some of examples of infectious disease tests:
More Infectious Disease Tests
Getting Tested for Infectious Diseases
Tests are usually ordered by a doctor. Before prescribing a test, the doctor typically asks about your risk factors, including your sexual and health history. The doctor also asks about any signs or symptoms of an infection in order to determine the most appropriate testing strategy.
While testing is usually performed in a hospital or doctor’s office, testing may also be available at clinics or other community health programs. Community health programs may offer free and confidential testing.
When interpreting your test results, it’s important to remember that some infectious diseases have window periods. A window period is the time between when a person is infected and when the disease shows up on a test. If a test is taken too soon after the initial infection, the results will not be accurate and the test will need to be repeated after the window period ends.
Costs of infectious disease testing
The cost of testing will vary by location and test type. Some clinics, usually community or nonprofit clinics, offer free or low-cost testing. Labs, clinics, and at-home testing companies may accept insurance to cover or lower your cost of testing.
Lab testing fees depend on the tests included in the panel, the lab, and your insurance coverage. There may even be an opportunity to test for multiple infections at once.
Types of sample collection
The sample required will depend on the particular test you’re taking. The most common specimens used for infectious disease tests are blood, urine, and saliva.
Getting test results
You will typically either receive the results of your test during a follow-up appointment with your doctor, over the phone, or through online medical charts. It’s important to discuss your test results with a health care professional who can help you manage your risk of complications associated with infection as well as to answer any questions you may have about your test results.
If test results are positive, it’s important to begin treatment as early as possible in order to reduce your risk of health complications. Your doctor can help you make a plan for sharing your results with those who you may have potentially spread the disease to and as well as if retesting is suggested after your treatment is completed.
Sources
Centers for Disease Control and Prevention. FastStats – Infectious Diseases. Updated September 6, 2022. Accessed October 4, 2022. https://www.cdc.gov/nchs/fastats/infectious-disease.htm
Chen, H., Liu, K., Li, Z., & Wang, P. (2019). Point of care testing for infectious diseases. Clinica chimica acta; international journal of clinical chemistry, 493, 138–147. https://doi.org/10.1016/j.cca.2019.03.008
Food and Drug Administration. Infectious Disease Tests. Updated February 13, 2020. Accessed October 4, 2022. https://www.fda.gov/vaccines-blood-biologics/infectious-disease-tests
Food and Drug Administration. Testing Human Cells, Tissues, and Cellular and Tissue Based Product (HCT/P) Donors for Relevant Communicable Disease Agents and Diseases. Updated February 10, 2021. Accessed October 4, 2022. https://www.fda.gov/vaccines-blood-biologics/safety-availability-biologics/testing-human-cells-tissues-and-cellular-and-tissue-based-product-hctp-donors-relevant-communicable
Rabold R, Waggoner, J. Rapid Diagnostic Tests for Infectious Diseases. Updated June 24, 2019. Accessed October 4, 2022. https://wwwnc.cdc.gov/travel/yellowbook/2020/posttravel-evaluation/rapid-diagnostic-tests-for-infectious-diseases
Tran, N. K., Albahra, S., Rashidi, H., & May, L. (2022). Innovations in infectious disease testing: Leveraging COVID-19 pandemic technologies for the future. Clinical biochemistry, S0009-9120(21)00341-6. Advance online publication. https://doi.org/10.1016/j.clinbiochem.2021.12.011
