Objective: To find the number of people with detectable antibodies to SARS-COV2 from a sampling of adults who have no known exposure or clinical illness. Eligibility: Adults ages 18 and older without a confirmed COVID19 infection or current symptoms consistent with COVID19 Design: Participants will enroll and give consent over the phone. They will be screened over the phone with a health assessment questionnaire. They will be screened for COVID19 using the NIH COVID19 screening questionnaire. Participants will give a blood sample. They can go to the NIH Clinical Center or do home blood sampling. In-person collection at NIH is preferred. If participants go to NIH, 2 tubes of blood will be taken. If participants do home sampling, they will be sent a home sampling kit. The kit contains gauze, an alcohol pad, a lancet, collection devices, and shipping materials. It also contains detailed instructions. They will collect 80ul of blood and mail it to the NIH lab. Participants may enroll in the study up to 4 times. They cannot enroll within 30 days of previous enrollment. 可以去NIH center采血，也可以根据指示在家采血。NIH prefers前者，但想来后者会更受欢迎。
这个情况似乎不合格？