COVID-19 Testing at Emerson Hospital

Emerson Hospital offers testing for COVID-19 for patients with a physician’s order. If you are experiencing symptoms, please call your primary care physician. You will be given instructions on how to get care without exposing other people to a potential illness. If it is determined that you require testing, you will be instructed on where to go and what to do.

Testing is also available at the Emerson Urgent Care Centers in Hudson and Littleton. Drive-up testing with a physician's order is available at Littleton. Please call 978-287-8990 to confirm availability at either of those locations.

What tests are available for diagnosing COVID-19?

Viral tests, also referred to as PCR tests, are used to diagnose COVID-19. The test is collected by a nasal swab and the results are usually back within two days. If your test is positive, it is over 99 percent accurate in diagnosing a COVID-19 infection. However, up to thirty percent of people who are with COVID-19 will test negative by the viral test. The test is less likely to be positive the longer it has been since the start of your symptoms. The viral test becomes negative over time so it is not used to show if you have had a past infection.

If you have symptoms of COVID-19, or have been in close contact with someone who has COVID-19, call your doctor and they will inform you of where to be tested.

What is antibody testing?

Antibody testing, also referred to as serology testing, checks a sample of a person’s blood to determine if your body has produced proteins that fight COVID-19. It typically takes between one and three weeks to develop these proteins, known as antibodies. Some people may take even longer to develop antibodies and some people may not develop antibodies. Antibody tests are generally not used to diagnose acute COVID-19. PCR (viral) tests are used to diagnose COVID-19.

What does a positive antibody test mean?

A positive test may mean that you may have been infected with the COVID-19 virus. The antibody test has a significant rate of false positives (people getting a positive antibody test who were not actually infected).

More importantly, what does a positive antibody test not tell you?

A positive test does not mean that you are immune to COVID-19. It is not known yet if having antibodies to COVID-19 can protect you from getting infected again. Even if they do protect you, it is unknown how long that protection will last.

WheN is antibody testing useful?  

Antibody testing can be offered as a method to support the diagnosis of COVID-19 illness for those who present late (and who therefore may have a false-negative COVID-19 PCR test result).

What is the Massachusetts Department of Health’s (MDPH) position on antibody testing?

MDPH does not recommend antibody testing at this time. Antibody tests are not indicated for diagnostic purposes. In order to be appropriately interpreted, more data is needed on the performance characteristics of these tests, the immune response to COVID-19, the timing and duration of antibody response, and how antibodies correlate to protective immunity.

What are the key points about the use of serologic/antibody test results?

Serologic tests should:
  • NOT be used to determine a person’s immunity to COVID-19
  • NOT be used to make decisions about relaxing or not following social distancing guidelines
  • NOT change the use of personal protective equipment (PPE) by health care workers and first responders
  • NOT be used to make decisions about returning persons to the workplace


Individual COVID-19 viral (PCR) tests at Emerson Hospital cost $51.31. However, there is no cost-sharing for this test and patients will not be charged at all. All testing will be billed to insurance companies. If a patient does not have insurance and is self-pay, they will not be responsible for the cost of the test. (Please note: This pricing information does not pertain to antibody tests.)