Patel et al. assessed the duration of antibody response to SARS-CoV-2 infection in health care personnel. A convenience sample of health care personnel at Vanderbilt University Medical Center was used. Participants were tested for seroprevalence between April 3 and April 13, 2020 (baseline) and June 2 and June 27, 2020 (60-day follow-up). A total of 249 participants were tested at baseline and 230 (92%) returned for the second test. Nineteen (7.6%) tested positive for anti-SARS-CoV-2 antibodies at baseline. Eight (42%) of these individuals remained seropositive throughout the 60 days with six (75%) reporting symptoms prior to the baseline visit. The other 11 (58%) tested negative at the follow-up test. Of these 11, five (45%) reported symptoms prior to the baseline visit. All 19 participants who tested positive at baseline showed a decrease in antibody concentration over the 60-day period. Those who remained seropositive over the 60-day period showed a higher signal-to- threshold ratio at baseline than those who initially tested positive, but then tested negative the second time (4.8 vs. 1.4). The findings suggest cross-sectional seroprevalence studies may not accurately assess rates of prior infection as antibody concentrations appear to decrease below the threshold of detection over time.