Inclusion Criteria:

* NCCAPS STUDY ELIGIBILITY CRITERIA:
* Patient must have a prior or current cancer diagnosis (e.g., solid tumor or hematologic malignancy) and cancer treatment that fits into one of the three following categories:

* Metastatic (stage IV) solid tumor, any hematologic malignancy, or any central nervous system (CNS) malignancy, and:

* Patient is receiving eligible active treatment (defined as current treatment or treatment within the 6 weeks prior to their first positive SARS-CoV-2 test collection) or is expected to begin receiving treatment within 2 weeks of study enrollment
* Eligible active treatment types are chemotherapy, immunotherapy, monoclonal antibody therapy (e.g., rituximab, trastuzumab, cetuximab), targeted therapy (e.g., BRAF/MEK inhibitor, EGF-R inhibitor), endocrine therapy, radiation therapy, or targeted radionuclide therapy; OR
* Non-metastatic (Stage I-III) solid tumor and:

* Patient is receiving eligible active treatment (defined as current treatment or treatment within past 6 weeks prior to their first positive SARS-CoV-2 test collection) or is expected to begin receiving treatment within 2 weeks of study enrollment
* Eligible active treatment types for non-metastatic solid tumor patients are intravenous chemotherapy, immunotherapy, targeted therapy, radiation therapy, targeted radionuclide therapy, or monoclonal antibody therapy (except as noted below)

* HER2-targeted therapy (trastuzumab, pertuzumab, neratinib, ado-trastuzumab) that is not accompanied by chemotherapy is NOT considered an eligible active treatment
* Patients on endocrine therapy alone are not eligible; OR
* Prior or current transplant for the treatment of cancer:

* Patient has received an allogenic stem cell/bone marrow transplant or chimeric antigen receptor (CAR)-T cell or other modified cellular therapy at any time; or
* Patient is currently receiving treatment or prophylaxis for graft graft versus (vs.) host disease; or
* Patient has received an autologous stem cell/bone marrow transplant within the past 2 years
* Patient must have documented positive viral test result for SARS-CoV-2

* For patients 18 years of age or older, the specimen collection for the patient's FIRST positive test must have occurred no earlier than 14 days prior to enrollment
* For patients under 18 years of age, the specimen collection for the patient's first positive test must have occurred after January 31, 2020
* The viral test can be either a nucleic acid (polymerase chain reaction \[PCR\]) test or an antigen test. Serological or antibody tests are not allowed
* Any specimen source (e.g., nasopharyngeal swab, oropharyngeal swab, etc.) is allowable for the viral SARS-CoV-2 test
* Patients with prior negative viral SARS-CoV-2 test(s) are eligible if they are being tested again
* The SARS-CoV-2 test must be a validated diagnostic assay performed in accordance with the most recent guidance issued by the Food and Drug administration (FDA) in the Policy for Coronavirus Disease-2019 Tests During the Public Health Emergency. This policy is available at: https://www.fda.gov/regulatory-information/search-fda-guidance-document…
* Human immunodeficiency virus (HIV)-infected patients are eligible
* Patients with CNS metastases are eligible
* Co-enrollment on other clinical trials (for cancer or for COVID-19) is allowed
* PEDIATRIC COVNET COHORT ELIGIBILITY CRITERIA:

Patients should only be enrolled in the pediatric COVNET cohort if they are not eligible for the main NCCAPS Study cohort or decline to participate in the main study

* Patient must be \< 18 years of age
* Patient must have a positive SARS-CoV-2 viral test after January 31, 2020
* Patient must have a current or prior diagnosis of cancer. Active cancer treatment is not required
* Note: Patients who enroll on Pediatric COVNET cohort will not be followed longitudinally; study data collection involves only a single questionnaire and research blood collection. A separate consent document is provided for the Pediatric COVNET cohort