While all seven regions in Whatcom County are seeing post-holiday COVID-19 spikes, three saw their infection rates double last week and one more than tripled — yes, tripled — in just seven days.

Northern parts of the county saw the largest jumps last week, according to data released Wednesday by the Whatcom County Health Department, as the Nooksack Valley and Lynden school district regions each saw their total number of confirmed cases jump by more than 100.