President Joe Biden has ordered enough vaccines to immunize every American against COVID-19, and his administration says it’s using the full force of the federal government to get the doses by July. There’s a reason he can’t promise them sooner.
Vaccine supply chains are extremely specialized and sensitive, relying on expensive machinery, highly trained staff and finicky ingredients. Manufacturers have run into intermittent shortages of key materials, according to the U.S. Government Accountability Office; the combination of surging demand and workforce disruptions from the pandemic has caused delays of four to 12 weeks for items that used to ship within a week, much like what happened when consumers were sent scrambling for household staples like flour, chicken wings and toilet paper.
Read more at ProPublica.