The Centers for Disease Control and Prevention (CDC) bought access to location data from tens of millions of American phones. They used the data to analyze the compliance of curfews, track neighbor-to-neighbor-visits, visits to churches, etc. The data was purchased for the pandemic, but according to documents, the CDC intended to use it for more-general purposes too.
In terms of privacy: Although the data is aggregated and reworked to remove personal information, it can be manipulated to track specific individuals and poses a breach of privacy.
Nonpublic information: Researchers could only obtain the CDC’s purchase through a Freedom of Information Act (FOIA) request. Many have been concerned that the CDC would try to track Americans for pandemic and vaccine-related purposes, commonly citing Australia’s tracking application launched in 2020.