Meeting the health challenges of displaced populations from Ukraine

[摘要] up, and known differences related to health-care seeking exposure, largely driven by social and cultural inclinations that are not part of a standard electronic medical record.6 Still, assuming consistent application of the methods described in this Article by Rearte and colleagues,5 all future estimates will be subject to the same sources of potential bias, thus providing a reliable tool for continuous monitoring of vaccine-induced immunity in the population, along with the changing of the seasons, and dominant variants. Evaluating the real-world effectiveness of vaccines for any disease is challenging, but even more so with COVID-19 because the roll-out of vaccines occurred with unprecedented speed over divergent social and geographical environments. These vaccines were developed during the early period of the pandemic when SARS-CoV-2 variants were poorly understood. The roll-out in Argentina occurred when the lambda (C.37) variant was the dominant subtype in the continent of South America.5 Argentina is now experiencing a surge in cases, most likely linked to omicron (B.1.1.529).7 Unlike other continents, the delta (B.1.617.2) variant has not developed much of a foothold in the region, but the emergence of omicron as a highly transmissible variant now necessitates careful monitoring to determine the spread of it in South America and whether new mutations weaken the morbidity associated with infection. Evidence from North America reported in early 2022 indicated that two doses of vaccine may be less effective than hoped at protecting against omicron infection, but that a third vaccine dose with an mRNA vaccine offered some