Measles virus transmission patterns and public health responses during Operation Allies Welcome: a descriptive epidemiological study

Real-Time Use of a Dynamic Model To Measure the Impact of Public Health Interventions on Measles Outbreak Size and Duration — Chicago, Illinois, 2024

“…If mass vaccination had been delayed by 1 week, there would have been an eightfold increase (from 1% to 8%) in the chance of an outbreak of 100 or more cases over the scenario in which mass vaccinations were deployed on March 8. These results are consistent with those from the OAW response, in which a modeled 7-day delay in vaccination would have yielded a 50% increase in median outbreak size ( 3 ). In addition, if public health notification of the index case had occurred when measles was first clinically suspected, an opportunity to implement mass vaccination would have occurred sooner, further reducing the chance of a large outbreak.…”

“…CDC adapted a model of measles transmission in a congregate setting previously developed during the 2021 Operation Allies Welcome (OAW) response ( 3 ). In this model, persons are placed into compartments representing their state relative to measles infection (i.e., susceptible, exposed, infected, and removed), age, and pregnancy status.…”

“…In this model, persons are placed into compartments representing their state relative to measles infection (i.e., susceptible, exposed, infected, and removed), age, and pregnancy status. Compared with the OAW model ( 3 ), this model also included a time-varying intervention representing active case-finding and a case ascertainment delay (Supplementary Figure, https://stacks.cdc.gov/view/cdc/155330 ). Model structure and parameterization evolved over the course of the outbreak; in this report, the retrospective predictions from the final model version are presented.…”

Measles and Rubella Diagnostic and Classification Challenges in Near- and Post-Elimination Countries

“…However, the limited sequence information provided by N-450 may not always be sufficient to provide substantial evidence for or against local transmission. Sequencing additional regions of the measles genome by partial or whole-genome sequencing may be able to increase the resolution needed to distinguish between chains of transmission [ 43 , 44 ].…”