Delta variant could drive herd immunity threshold over 80%


Dealing with a disconnect

In response to a reporter’s question about the possibility that the large crowd at the Lollapalooza music festival in Chicago could become a superspreader event, Dr. Emanuel said, “it is worrisome.”

“I would say that, if you’re going to go to a gathering like that, wearing an N95 mask is wise, and not spending too long at any one place is also wise,” he said.

On the plus side, the event was held outdoors with lots of air circulation, Dr. Emanuel said.

However, “this is the kind of thing where we’ve got a sort of disconnect between people’s desire to get back to normal ... and the fact that we’re in the middle of this upsurge.”

Another potential problem is the event brought people together from many different locations, so when they travel home, they could be “potentially seeding lots of other communities.”

Boosters for some, for now

Even though not officially recommended, some fully vaccinated Americans are seeking a third or booster vaccination on their own.

Asked for his opinion, Dr. Emanuel said: “We’re probably going to have to be giving boosters to immunocompromised people and people who are susceptible. That’s where we are going to start.”

More research is needed regarding booster shots, he said. “There are very small studies – and the ‘very small’ should be emphasized – given that we’ve given shots to over 160 million people.”

“But it does appear that the boosters increase the antibodies and protection,” he said.

Instead of boosters, it is more important for people who haven’t been vaccinated to get fully vaccinated.

“We need to put our priorities in the right places,” he said.

Emanuel noted that, except for people in rural areas that might have to travel long distances, access to vaccines is no longer an issue. “It’s very hard not to find a vaccine if you want it.”

A remaining hurdle is “battling a major disinformation initiative. I don’t think this is misinformation. I think there’s very clear evidence that it is disinformation – false facts about the vaccines being spread,” Dr. Emanuel said.

The breakthrough infection dilemma

Breakthrough cases “remain the vast minority of infections at this time ... that is reassuring,” Dr. Franco said.

Also, tracking symptomatic breakthrough infections remains easier than studying fully vaccinated people who become infected with SARS-CoV-2 but remain symptom free.

“We really don’t have a good handle on the frequency of asymptomatic cases,” Dr. Emanuel said. “If you’re missing breakthrough infections, a lot of them, you may be missing some [virus] evolution that would be very important for us to follow.” This missing information could include the emergence of new variants.

The asymptomatic breakthrough cases are the most worrisome group,” Dr. Emanuel said. “You get infected, you’re feeling fine. Maybe you’ve got a little sneeze or cough, but nothing unusual. And then you’re still able to transmit the Delta variant.”

The big picture

The upsurge in cases, hospitalizations, and deaths is a major challenge, Dr. Emanuel said. “We need to address that by getting many more people vaccinated right now with what are very good vaccines.”

“But it also means that we have to stop being U.S. focused alone.” He pointed out that Delta and other variants originated overseas, “so getting the world vaccinated ... has to be a top priority.”

“We are obviously all facing a challenge as we move into the fall,” Dr. Emanuel said. “With schools opening and employers bringing their employees back together, even if these groups are vaccinated, there are going to be major challenges for all of us.”

A version of this article first appeared on Medscape.com.


Recommended Reading

The VA, California, and NYC requiring employee vaccinations
The Hospitalist
CDC calls for masks in schools, hard-hit areas, even if vaccinated
The Hospitalist
Pfizer vaccine protection wanes after 6 months, study finds
The Hospitalist
As common respiratory viruses resurface, children are at serious risk
The Hospitalist
Vaccinated people infected with Delta remain contagious
The Hospitalist
‘A few mutations away’: The threat of a vaccine-proof variant
The Hospitalist
Hospital disaster preparation confronts COVID
The Hospitalist
COVID-19: Delta variant is raising the stakes
The Hospitalist
Never prouder to be a hospitalist
The Hospitalist
Increases in new COVID cases among children far outpace vaccinations
The Hospitalist
   Comments ()