ABSTRACT
We describe the epidemiology of COVID-19 exposure, preceding illness, and SARS-CoV-2 testing in a large population with MIS-C during the first 18 months of the COVID-19 pandemic. The majority of cases had exposure, preceding illness, or positive SARS-CoV-2 testing 4-8 weeks before MIS-C onset. Serology can help establish epidemiological link to COVID-19 when past infection or exposure are unknown.
Subject(s)
COVID-19 , COVID-19/complications , COVID-19/epidemiology , COVID-19 Testing , Child , Humans , Los Angeles/epidemiology , Pandemics , SARS-CoV-2 , Systemic Inflammatory Response Syndrome/diagnosis , Systemic Inflammatory Response Syndrome/epidemiologyABSTRACT
During July 2021, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B.1.617.2 variant infections, including vaccine breakthrough infections, occurred after large public gatherings in Provincetown, Massachusetts, USA, prompting a multistate investigation. Public health departments identified primary and secondary cases by using coronavirus disease surveillance data, case investigations, and contact tracing. A primary case was defined as SARS-CoV-2 detected <14 days after travel to or residence in Provincetown during July 3-17. A secondary case was defined as SARS-CoV-2 detected <14 days after close contact with a person who had a primary case but without travel to or residence in Provincetown during July 3-August 10. We identified 1,098 primary cases and 30 secondary cases associated with 26 primary cases among fully and non-fully vaccinated persons. Large gatherings can have widespread effects on SARS-CoV-2 transmission, and fully vaccinated persons should take precautions, such as masking, to prevent SARS-CoV-2 transmission, particularly during substantial or high transmission.