A collaboration by
In partnership with these County Public Health Departments
We send invitations by mail to randomly picked households in your county.
Use the access code in your invitation letter to order testing kits for up to one adult and one child in your household.
Enter in the 6-digit code found on your test box to take the survey and learn how to use the lancet to place blood spots on a piece of filter paper.
Mail the kit back to us using the pre-paid envelope and we'll mail your results back.
Your household has been randomly chosen to take part in a free statewide COVID-19 study. We want to learn how many people in California may have COVID-19 antibodies and how it is impacting our communities.
Please enter the activation
and zip code below.
Frequently Asked Questions
The California Department of Public Health will randomly mail letters to households asking them to take part in this study. This invitation letter will have a special 8-digit access code that people can use if they want to join the study. Up to 2 people (1 adult and 1 child older than 6 months) from each household can participate. If there are multiple adults and children living in your household, we ask that the adult and child with the nearest upcoming birthday join this study.
Only households that receive a mailed invitation letter can join. If you get an invitation letter, do not share the letter with people in a different household, even if you do not want to join the study.
If you get an invitation letter for this study, it will have a unique access code that you can use to register for the study online. Here are the steps for registering and taking part in the study:
1. Find the 8-digit access code included in your invitation letter, and enter the code online at www.calscope.org along with your zip code.
2. When you register online, you will choose if 1 or 2 people (1 adult and/or 1 child) from your household will be part of the study. You will not be asked to give names of people joining the study when you register.
3. After you register for the study online, you will receive blood test kit(s) in the mail within 1-2 weeks.
4. When you receive the kit(s), you should review the information included in the kit and make sure that any children participating in the study have permission from a parent or legal guardian to take part in the study.
5. When you’re ready to begin, go to calscope.org/#gotkit and activate the test kit by entering in the 6-character code starting with a “C” along with your zip code.
6. After you activate your kit online, you will complete the survey online and follow the directions to collect the blood sample.
7. When you are done collecting the blood sample, mail the kit back using the pre-paid return mailer bag included in the test kit package.
If you need help at any point while registering or completing the survey or blood test, you can contact the CalScope study team by phone at 1-833-580-1333 or fill out this online support form.
No, you do not have to join the study if you don’t want to. If no adult from your household wants to join the study, but a child is willing, the child may join the study if they have permission from a parent or legal guardian to join. An adult must also be willing to help the child register and take part in the study. Children must be at least 6 months old to take part in the study. Anyone who decides to join the study can choose to skip any survey questions they do not want to answer. You may also withdraw from or drop out of the study at any time.
If no one in the household wants to complete either the survey and/or the blood test kit, you should throw away the invitation letter. The invitation letter is only for the household address that it is mailed to, so please do not give the invitation letter to other people who live at a different address.
A positive antibody test, or a result that says, “antibodies are present,” means that you may have been infected with the virus that causes COVID-19 (SARS-CoV-2) in the past. A positive antibody test does not mean that you are currently infected or sick with COVID-19. You may also have a positive antibody test if you have had a COVID-19 vaccine. It can take 1-3 weeks or longer for a person’s immune system to develop antibodies after being infected with a virus or receiving the COVID-19 vaccine.
It’s important to know that a positive antibody test may be wrong, and that you may have never been infected with the virus before. This kind of error (called a “false positive”) is uncommon, and only happens about 5 to 15 times out of 100 tests. This is the first time these antibody tests have been used for testing at home, so we can’t be 100% sure of the exact accuracy of these tests yet.
The antibody test used in this study is meant to be used for public health purposes only. The results of this test should not be used to make medical decisions. Scientists do not know if having antibodies to the COVID-19 virus protects you from getting infected again in the future. The test used in this study has been designed and tested for research but has not been approved by the U.S. Food and Drug Administration (FDA). You should not change your behavior based on your result of the antibody test. You should continue to follow public health recommendations to prevent the spread of COVID-19.For more information about COVID-19 tests that are used to look for past infection, please visit the CDC COVID-19 Test for Past Infection website.
A negative antibody test, or a result that says “antibodies are absent”, means the test did not find antibodies in your blood, meaning you may never have been infected with the virus that causes COVID-19 (SARS-CoV-2) in the past. However, because it can take 1-3 weeks or longer for a person’s immune system to develop antibodies after being infected with a virus, this test can’t tell whether you are currently infected with the virus.
It’s important to know that a negative antibody test may be wrong, and that you may actually have been infected with the virus before. For example, the test may not have been able to detect any of the antibodies that you have in your blood. The test may also have been taken too early or too late after infection. This kind of error (called a “false negative”) is uncommon, and only happens about 1 time out of 100 tests. This is the first time these antibody tests have been used for testing at home, so we can’t be 100% sure about the exact accuracy of these tests yet.
The antibody test used in this study is meant to be used for public health purposes only. The results of this test should not be used to make medical decisions. Scientists do not know if having antibodies to the virus that causes COVID-19 protects you from getting infected again in the future. The test used in this study has been designed and tested for research but has not been approved by the U.S. Food and Drug Administration (FDA). You should not change your behavior based on your result of the antibody test. You should continue to follow public health recommendations to prevent the spread of COVID-19.
For more information about COVID-19 tests that are used to look for past infection, please visit the CDC COVID-19 Test for Past Infection website.
People who may have already received some or all of their COVID-19 vaccines, tested positive for COVID-19 before, or are routinely tested, are allowed to join the study.
People who are vaccinated against the virus that causes COVID-19 infection will develop antibodies that can be detected by our test. It will take 1 to 3 weeks after you have received the vaccine before your immune system develops antibodies. Depending on how many doses of the vaccine you have had, and how long ago you got the vaccine, your antibody test may or may not be positive.
This study is designed to learn more about how many people in California may have been infected with and have developed antibodies to the coronavirus (SARS-CoV-2), which causes COVID-19, or may have developed antibodies due to getting a vaccine. Antibodies are proteins in the blood that are a made by a person’s immune system when they are infected with a virus. If a person has antibodies in their blood, it is a sign that they have been infected with a virus before, even if they didn’t have symptoms. People may develop antibodies a few weeks after being infected with a virus or getting vaccinated. An antibody blood test won’t be able to tell if you currently have COVID-19 or not.
This test is different from other COVID-19 tests, which usually involve a nose or throat swab. These swab tests are used to see if someone is currently sick or infected with the virus that causes COVID-19.
Yes, your participation in this study is confidential. The survey will not ask for your personal information, such as your name or birthday. All survey and blood test results are collected anonymously (meaning we don’t ask for your name) in order to protect your identity.
In order to provide you with study updates, we will ask you to provide your phone number and email, but you don’t have to share this information if you don’t want to. As soon as your participation is completed or if you withdraw from the study, any contact information that you shared with us will be erased.