Skip to main content

CDC document: Delta variant as contagious as chickenpox

Vaccines remain very effective at preventing severe illness from the delta variant, however.

A federal document from the Centers for Disease Control and Prevention (CDC) says the delta variant of the coronavirus is as transmissible as chickenpox, and more contagious than ebola, the common cold, smallpox, MERS, SARS and even the 1918 "Spanish" flu. 

The document, obtained by The Washington Post, warns that the delta variant can infect people who are fully vaccinated. Such cases are defined as "breakthrough" cases. Still, vaccine effectiveness remains very strong against severe illness, hospitalization and death. 

Overall, vaccines reduce delta's ability to cause severe disease by 10 fold, while showing a 3-fold reduction in infection. 

The slide below from the CDC document explains that the delta variant is highly contagious and likely causes more severe disease in the unvaccinated, while vaccines are at least 90% effective at preventing severe symptoms. 

Screen Shot 2021-07-30 at 1.27.42 PM

Between July 3-17 in Provincetown, Massachusetts, there were 469 COVID-19 cases identified in Massachusetts residents, and 346 (74%) of them were fully vaccinated people, according to the CDC. Of those infections, 133 samples underwent genomic sequencing and 90% of them were found to be the delta variant. 

However, the CDC notes that there will naturally be more breakthrough cases simply because more and more Americans are getting vaccinated. As The Washington Post stated, the information "echoes data seen from studies in other countries, including highly vaccinated Singapore, where 75 percent of new infections reportedly occur in people who are partially and fully vaccinated."

The CDC document says non-pharmaceutical interventions (NPIs) are "essential to prevent continued spread with current vaccine coverage." NPIs include social distancing and wearing a mask. 

Earlier this week, the CDC changed its masking guidance by urging everyone, even the vaccinated, to wear masks indoors in communities with "substantial or high" virus circulation. There are more than 30 counties that meet that criteria in Minnesota, according to a Friday update. 

CDC - MN counties high or substantial transmission - July 30, 2021

The Minnesota Department of Health says approximately 75% of all cases that have undergone genomic sequencing in July have been identified as the delta variant. Delta is fueling the state's rising case counts and hospital admissions. 

The state reported more than 700 new cases Friday, along with 231 people hospitalized with COVID-19, including 64 patients in intensive care. The 64 ICU admissions are the most since June 3 and the 167 non-ICU admissions are the most since June 4.

Next Up

Screen Shot 2022-05-23 at 9.58.36 PM

Eric Perkins, Miss Minnesota, Paul Fletcher create new podcast

The podcast is released Tuesdays at 8 a.m. and is available wherever you find podcasts.

Mock aircraft cabin.

MSP Airport debuts mock aircraft to help ease flying anxiety

The pre-flight experiences cover the TSA screening procedure, exploring a terminal, boarding a plane and meeting a pilot, and preparing for takeoff.

Scripps National Spelling Bee

These Minnesota kids will be competing at National Spelling Bee

The upcoming event in Maryland will be the first fully in-person Scripps National Spelling Bee since 2019.

covid, kids

New data shows how omicron has impacted kids in Minnesota

The new data shows breakthrough data during the omicron period, which began Dec. 19, 2021.

Javen Juan Moreno

Albert Lea shooting suspect arrested after 3 weeks on the run

He is accused of shooting a man in the upper thigh on May 1.

motorcycle

Motorcyclist, 59, killed after losing control on right curve

The Harley Davidson rider was thrown from his bike.

state capitol Minnesota

Minnesota's 2022 legislative session: What's happening?

A list of items agreed upon and yet to reach any bipartisan agreement in the latest legislative session.

water drain

Water main break floods 40-45 homes in St. Louis Park

The city says the rupture happened on Minnetonka Boulevard.

Eli Hart

Charges: 6-year-old Eli Hart shot up to 9 times by his mother

The 28-year-old is facing 2nd-degree murder charges.

dave lee wcco radio

Former WCCO Radio host Dave Lee moves into podcasts

His new podcast, called 'My First Concert,' launched last week.

Tow Boat

Tow boat collides with Mississippi River lock and dam in Alma, WI

The crash remains under investigation by the United States Coast Guard.

unsplash school bus

Police: Man in minivan approached kids, claimed he was former principal

Investigators say children were approached by a man in a white minivan who falsely claimed he'd been a local school principal.

Related

covid

How the Delta variant is affecting Minnesota's COVID-19 status

The number of cases identified as the Delta variant are rising.

Pexels - woman grocery shopping mask covi

CDC: Masks recommended in places with 'substantial or high' transmission

The agency is also recommending masks for everyone in K-12 schools.

covid

Delta variant circulating in Minnesota, health officials urge vaccination

"The unvaccinated are still at risk for the virus – and it has a way of finding the unvaccinated."

covid

Minnesota health officials watching closely for omicron variant

Health leaders do not yet know how transmissible or severe the new variant is.

coronavirus, ICU, COVID-19

Deaths rising rapidly in Minnesota as delta variant surges

October 2021 had more COVID deaths than October 2020, when there wasn't a vaccine.

coronavirus, covid-19

CDC director urges vigilance to prevent 'avoidable surge' of COVID

Minnesota's 7-day rolling average of new cases is rising.

Minnesota-Canada border

CDC: Do not travel to Canada, even if you are vaccinated

The CDC has issued its highest travel alert level for Canada.

Screen Shot 2021-03-29 at 12.22.38 PM

CDC director 'scared' of COVID trajectory, feeling of 'impending doom'

The warning comes at a time when Minnesota's cases are rising.