Several municipalities in the US did do randomized sero surveys earlier in the pandemic. I can’t provide a citation but largely these were abandoned because th

Several municipalities in the US did do randomized sero surveys earlier in the pandemic. I can’t provide a citation but largely these were abandoned because they were influence by a couple factors * participation was obviously still voluntary and largely mirrored the same trends you describe * the data was not short term actionable and took up testing infrastructure at the time * it was dangerous - I.e., public health workers were threatened, assaulted, and in at least one case shot at.