What It Means to Be Asymptomatic

When You Are Ill—and, in Some Cases, Contagious—but You Feel Fine

The term "asymptomatic" means the absence of symptoms. If your provider tells you that you have a disease or condition but are asymptomatic, it means your medical condition is not producing any noticeable symptoms indicating that you are sick.

The term is often used to describe cases of illness that are symptom-free for all or part of the time. However, the term "pre-symptomatic" is sometimes used to differentiate those cases that start with no symptoms but then go on to develop them.

This article goes over the meaning of asymptomatic and covers different types of asymptomatic illnesses and conditions. You will learn why being asymptomatic can be a concern to both your health and the health of others, how asymptomatic conditions and diseases are diagnosed, and how they are treated.

Understanding Asymptomatic Illnesses

Laura Porter / Verywell

What Asymptomatic Means

Asymptomatic means that you aren't showing any symptoms. You could be asymptomatic for two different reasons: You may have recently recovered from an illness or a condition and no longer have symptoms, or you may have an illness or a condition but no symptoms.

It's hard to know whether an asymptomatic condition will eventually cause symptoms or not. If you have an asymptomatic condition like high blood pressure or diabetes, you may have to make healthcare decisions to try to improve your long-term quality of life or survival.

If you have an asymptomatic disease that is contagious, you may need to take steps to prevent spreading the condition to other people.

However, an asymptomatic finding doesn't always mean you should, or can, do anything to change the situation. In some cases, the early detection of a condition will not lead to an improved quality of life or greater survival. In this case, additional testing and medical interventions would not be helpful—in fact, they could be harmful.

Not only is this situation emotionally upsetting and stressful, but the unnecessary medical work-up itself could pose risks (e.g., the surgical risk from a biopsy) and can be costly.

When You Might Be Asymptomatic

It may seem odd that you can be unwell and not know it, but there are a variety of instances in which this can occur.

You may be asymptomatic under the following circumstances:

  • Your immune system is successfully fighting off an invader before you can recognize that it is there (e.g., the flu virus or the bacterium that causes strep throat).
  • You are in recovery or remission from an illness in which you experienced symptoms (e.g., a sinus infection).
  • You are sick with something that typically only shows symptoms in more advanced stages (e.g., chlamydia or colon cancer).
  • You have a condition that slowly develops (e.g., high blood pressure or diabetes).
  • You have a chronic illness that goes through recurring cycles of being asymptomatic and then having a return of symptoms (e.g., the relapsing-remitting pattern seen in multiple sclerosis).

In some cases, screening tests can detect an issue in people even if they are asymptomatic. However, if you don't feel sick, you're less likely to seek care.

What Diseases Are Asymptomatic?

There are many diseases that can be asymptomatic, from certain cancers to ones that affect the bones and eyes. In addition to the conditions noted above, other conditions that can be present without symptoms include:

Can You Have COVID-19 Without Symptoms?

Yes. Although you may not feel sick, you can still spread the virus to others if you are asymptomatic. If COVID-19 symptoms do appear, they usually show up between two and 14 days after exposure.

If you've been exposed to someone who is infected, you may want to get tested whether you are symptomatic or not.

If you don't have any symptoms but test positive, the Centers for Disease Control and Prevention recommends taking precautions for the next five days. If you develop any symptoms, you should self-isolate until your symptoms improve for 24 hours.

Concerns With Being Asymptomatic

Being symptom-free can be a good thing for obvious reasons. But it can also delay diagnosis and treatment.

Since you're unlikely to change habits like going to work if you feel fine, you can unknowingly pass along infectious conditions to others.

Personal Health Risks

Being asymptomatic is concerning because it means you won't get the treatment you need at a time when a disease or condition may be most treatable and least likely to cause complications.

For example, if you have high blood pressure, but no symptoms, you still need treatment to avoid potential issues such as a stroke, kidney damage, and a heart attack.

If you have lung cancer, it may take years for you to experience symptoms. You may be asymptomatic even though the cancer is growing and spreading.

The disease may not be detected until its later stages (which is usually the case). It's most treatable, however, in stage 1.

Risks to Others

Even if you don't have symptoms of a contagious disease, you can still spread it to others. Not all conditions spread in the same way, but some common ways that viruses and infections can be transmitted include:

  • Though sexual activity
  • By breathing out, coughing, and sneezing
  • By touching contaminated surfaces, and then touching your eyes, nose, or mouth
  • By ingesting food or liquids containing tiny particles of infected feces

The amount of time you may be contagious depends on the condition or illness. Some diseases have a small contagion window, while others, such as gonorrhea, can be spread from person to person for years.

If you're unaware that you have a condition, you may not take precautions to avoid infecting other people. Precautions include things like having protected sex or practicing abstinence, washing your hands regularly, and social distancing until you're no longer contagious.

How Do I Know if I'm Asymptomatic?

Although you may not know to get tested for a disease if you're not experiencing symptoms, there are still ways to get a diagnosis before the condition worsens.

You may choose to be screened for a disease if you're at risk of being exposed to it or developing it, or a healthcare provider may recommend a screening for these reasons. For example, women who are ages 50 to 74 may be told to get a mammogram every two years to check for breast cancer, which is more common among older women. Most insurance plans are required to cover the screenings.

General health screenings, such as checking blood pressure and blood sugar (glucose) levels, can spot chronic conditions like hypertension and diabetes before they cause symptoms.

Additionally, if you don't have symptoms of an illness or disease but you know you were exposed to it, you might be able to find out if you have it by getting a test. For example, if a partner informs you that they have an STI, you may choose to get tested and find out that you also have it.

You can even test at home for some conditions, such as COVID-19.

Are Asymptomatic Cancers Overdiagnosed?

Sometimes screening tests can contribute to overdiagnosis, which is the diagnosis of a condition that wouldn't have caused symptoms or death. Overdiagnosis can have serious consequences and is relatively common for some types of cancers. For example, studies have estimated that 19% of breast cancer diagnoses and 20% to 50% of prostate cancer diagnoses stemming from cancer screenings are overdiagnosed.

What Should You Do if You're Asymptomatic?

If you've been around someone who's sick and think you may have a contagious disease, take care to prevent spreading it to others. Check in with a healthcare provider to get tested or, if possible, take an at-home test. Having a definitive answer will let you know what steps to take next.

Visiting your healthcare provider for screenings and routine testing can help you detect asymptomatic conditions that are not contagious, like high blood pressure or diabetes. Preventive care can be vital to your health.

For diseases like osteoporosis, hepatitis, and other asymptomatic conditions, regular check-ups allow your healthcare provider to monitor your condition as a way to prevent or slow progression. They let your provider see how well any treatment or lifestyle changes may be working.

Questions to Ask Your Healthcare Provider

  • What are the chances that I will develop the disease for which I'm now asymptomatic? How might that change with treatment?
  • What might treatment entail? What are the pros and cons?
  • What are the chances that nothing would happen if did nothing about the finding? (Sometimes looking at statistics is helpful.)
  • Is there concern that this condition is overdiagnosed?
  • What would you do if you were in my shoes?

Summary

If you are sick but do not have symptoms, it means you're asymptomatic. While you might feel free to go about your regular day-to-day activities since you aren't feeling sick, it's important to know that you still might be able to spread the illness to others even if you don't have symptoms.

Sometimes, an asymptomatic disease is picked up by a screening test. That said, asymptomatic conditions can go unchecked because people are less likely to seek care if they aren't feeling sick.

If your provider tells you that you have an asymptomatic illness or condition, ask your provider what steps you need to take to protect yourself and others.

11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  3. Centers for Disease Control and Prevention. Symptoms of COVID-19.

  4. Centers for Disease Control and Prevention. Overview of testing for SARS-CoV-2, the virus that causes COVID-19.

  5. Centers for Disease Control and Prevention. Preventing Spread of Respiratory Viruses When You’re Sick.

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  10. Centers for Disease Control and Prevention. What is breast cancer screening?

  11. National Cancer Institute. Crunching numbers: What cancer screening statistics really tell us.

Additional Reading

By Lynne Eldridge, MD
 Lynne Eldrige, MD, is a lung cancer physician, patient advocate, and award-winning author of "Avoiding Cancer One Day at a Time."