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Dr. Ashish Jha said Monday he is worried about the potential impact of the delta variant could have in the United States.
The highly transmissible coronavirus variant, which was first detected in India and is also known as B.1.617.2, has sparked an uptick in cases in the United Kingdom that may delay officials lifting coronavirus restrictions in that country. The strain is also driving new infections in southeastern China, where doctors report patients are becoming sicker more quickly, The New York Times reports.
At the end of last week, the delta variant accounted for 6 percent of all coronavirus infections in the U.S.
“I’m concerned about the Delta variant,” Jha wrote on Twitter. “Why? Most contagious variant yet. Wreaked havoc in India. Spiking cases in UK. Growing rapidly in the US.”
The dean of the Brown University School of Public Health said getting vaccinated is key to protecting against the strain.
“Help an unvaccinated friend get the shot,” he said.
I'm concerned about the Delta variant
— Ashish K. Jha, MD, MPH (@ashishkjha) June 14, 2021
Why?
Most contagious variant yet
Wreaked havoc in India
Spiking cases in UK
Growing rapidly in the US
So what do we do?
Get vaccinated
Help an unvaccinated friend get the shot
High vaccination rates is how we fight the Delta variant
Jha is not the only public health leader concerned about the delta strain.
Dr. Bob Wachter, chair of the University of California San Francisco, laid out in a lengthy Twitter thread why the variant is making him “nervous” and the argument for why more people should be taking the threat it poses seriously.
“If you’re not vaccinated: I’d be afraid,” he wrote. “Maybe even very afraid.”
The doctor pointed out that while some places have vaccination rates topping 70 percent, about 50 percent of the country over the age of 12 remains unvaccinated. In some states, the percentage of eligible, unvaccinated individuals is higher, at about two-thirds.
While vaccinated individuals don’t have to worry about the delta variant, particularly if they live in a community with high levels of vaccinations, unvaccinated individuals are at high risk of contracting COVID-19 if they are exposed, the doctor said.
While the chance of unvaccinated individuals being exposed is lower in communities where more people are vaccinated, Wachter said he is scared about what could happen this fall and winter.
“Reason: Delta,” he wrote.
According to Wachter, the delta variant appears more infectious than the alpha variant or B.1.1.7 strain, which was first detected in the U.K.
“This means the same exposure that a person might have had last year is now about twice as likely to result in Covid,” Wachter said. “Second, it’s looking like it is more serious, though we need more data to be sure. Third — and this is the big one — it does appear to be somewhat immune resistant. Before getting too freaked out about this, it’s worth noting that the data are reassuring, in a way: the efficacy of 2-doses of Pfizer is 88 percent, only a smidge lower than the 95 percent we’re used to, and still great.”
What is concerning, according to the doctor, is that data indicate that the first dose of Pfizer, normally about 80 percent protective, is only about 33 percent protective against the delta variant.
“What to do? For a vaccinated person, watch the Delta % in your region (currently ~6% in the U.S. & rising) & Covid cases in your community,” Wachter wrote. “If you’re seeing more cases & more Delta, I’d restore some precautions (esp. if you’re high risk) – at least indoor mask wearing (if you’ve stopped; BTW, I haven’t) in places w/ unvaxxed/unmasked folks. If you’re unvaxxed, get your shots! You may be reassured by a low, local case rate, but don’t be: it may be due to summer plus the still-low Delta fraction. Both will change.”
The US has been “lulled by the amazing efficacy of the vaccines” and because previous variants haven’t been “that nasty,” Wachter said.
As it is, the doctor said he is now expecting to see “significant” surges in the fall in populations that have low vaccination rates because of the strain.
COVID-19 is not yesterday’s news, Wachter stressed.
“Delta should ring the alarm & spur action,” he said. “We need FDA to fully authorize our vaccines, to step up research on boosters & faster approvals for kids. We also need > outreach to unvaxxed (incl. info on Delta) & vaccine mandates in risky settings (healthcare, nursing homes).”
Read his full thread below:
This thread by @Bob_Wachter on the Delta variant is terrific
— Ashish K. Jha, MD, MPH (@ashishkjha) June 14, 2021
It is well worth your time so please read it
Delta variant also has me feeling a little concerned about state of things in the US
A very contagious variant
1/3 of adults still not vaccinated
Its not great https://t.co/lo6xplFhoT
3/ Current U.S. situation is good. Cases, hospitalizations, & deaths are falling fast, largely due to our fabulous vaccines. In SF – w/ 70% of people aged >12 fully vaxxed – we’re nearly in a post-Covid world. Everybody’s opening up, including (on Tues) CA. That’s fine…for now.
— Bob Wachter (@Bob_Wachter) June 13, 2021
5/ Unvaccinated people remain at high risk of getting Covid… if they’re exposed to it. In April, I argued @washingtonpost that this is the most dangerous time for unvaccinated people (without prior Covid), since their bodies are no better … https://t.co/wH8F58Q9zV
— Bob Wachter (@Bob_Wachter) June 13, 2021
7/ …to be exposed to virus since community rates had fallen so much (due to kindness of vaccinated strangers). This remains true, which is why unvaxxed may well do OK for a while, probably through summer.
— Bob Wachter (@Bob_Wachter) June 13, 2021
But fall/winter now scares me a lot, much more than it did 2 weeks ago.
9/ There’s still debate over whether Alpha is more serious (some studies say yes, others no). But there’s no question that the vaccines (at least the 3 approved in the U.S.) work just fine against it. This meant that – even though it became the dominant virus in Israel, the UK…
— Bob Wachter (@Bob_Wachter) June 13, 2021
11/ Why is Delta scarier? First, it appears to be even more infectious than the Alpha variant, probably by a similar amount (~40% more infectious than Alpha.)(h/t @EricTopol for @BBC table below) This means the same exposure that a person might have had last year is now about… pic.twitter.com/wjMkpuDSIL
— Bob Wachter (@Bob_Wachter) June 13, 2021
13/ …data are reassuring, in a way: the efficacy of 2-doses of Pfizer is 88%, only a smidge lower than the 95% we’re used to, and still great.
— Bob Wachter (@Bob_Wachter) June 13, 2021
But the first dose data is concerning. Normally, a few weeks after dose 1, you’re about 80% protected (this was the argument for…
15/ …degree of vaccine/immune escape. And – though this isn’t proven – I’d worry that a fully vaccinated elder, or someone whose immunity stems from an infection >12 mths ago, won’t be sufficiently protected over time, if immunity falls below a threshold needed to thwart Delta.
— Bob Wachter (@Bob_Wachter) June 13, 2021
17/ … indoor mask wearing (if you’ve stopped; BTW, I haven’t) in places w/ unvaxxed/unmasked folks.
— Bob Wachter (@Bob_Wachter) June 13, 2021
If you’re unvaxxed, get your shots! You may be reassured by a low a local case rate , but don’t be: it may be due to summer plus the still-low Delta fraction. Both will change.
19/ …that Covid is yesterday's news, & that now seems like an awful bet. Moreover, I worry that a right-leaning Governor who opened up early & proudly (& has gotten away with it so far) will be stubbornly unwilling to reverse course, even in the face of surging cases & deaths.
— Bob Wachter (@Bob_Wachter) June 13, 2021
21/ Is the threat real? UK has been a step ahead of U.S. on vaccinations, & cases/deaths have fallen faster in UK than in U.S. But look at recent UK case # s – they’ve doubled in past 2 wks, as Delta became dominant strain (now 91% of UK cases). Reassuringly, deaths remain low… pic.twitter.com/1bp4Vbje6u
— Bob Wachter (@Bob_Wachter) June 13, 2021
23/ We’ve been lulled by the amazing efficacy of the vaccines & by fact that prior variants haven’t been all that nasty (esp. w/ regard to immune escape). Delta should ring the alarm & spur action. We need FDA to fully authorize our vaccines, to step up research on boosters,…
— Bob Wachter (@Bob_Wachter) June 13, 2021
25/ …psychologically prepped for some restrictions to return in fall (tho highly vaxxed places like SF will likely do fine). Nobody wants that, but the virus doesn’t care what we want.
— Bob Wachter (@Bob_Wachter) June 13, 2021
For unvaxxed, I wish you well but my sympathy is flagging. Your bad choice is looking worse.
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