HomeNewsNationalCOVID-19 live updates: US faces summer surge as delta variant spreadsCOVID-19 live updates: US faces summer surge as delta variant spreadsMon, July 26, 2021 by ABC NewsSHARE NOW Vichai/iStock(NEW YORK) — The United States is facing a COVID-19 summer surge as the delta variant spreads.More than 610,000 Americans have died from COVID-19, according to real-time data compiled by the Center for Systems Science and Engineering at Johns Hopkins University.Just 57% of Americans ages 12 and up are fully vaccinated, according to data from the Centers for Disease Control and Prevention.COVID-19 has infected more than 194 million people worldwide and killed over 4.1 million.Here’s how the news is developing Monday. All times Eastern:Jul 26, 9:11 am Symptomatic breakthrough infections rare, CDC data estimatesNew data shows how rare COVID-19 breakthrough infections likely are.With more than 156 million Americans fully vaccinated, about 153,000 symptomatic breakthrough cases are estimated to have occurred as of last week, representing approximately 0.098% of those fully vaccinated, according to an unpublished internal Centers for Disease Control and Prevention document obtained by ABC News. These estimates reflect only the adult population and do not include asymptomatic breakthrough infections.But in Provincetown, on Massachusetts’ Cape Cod, at least 551 COVID-19 infections, many of them breakthroughs, were confirmed after the July Fourth weekend. Of the Massachusetts residents who tested positive as a result of the Provincetown cluster, 69% reported to be fully vaccinated, according to local officials.Most people were symptomatic. Apart from three hospitalizations, symptoms from cases associated with this cluster were known to be mild and without complication, said Alex Morse, the town manager for Provincetown.Copyright © 2021, ABC Audio. All rights reserved.