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Zero Hour Health & Zedic Newsletter - Tuesday, July 20th

Breakthrough infections 101, pediatricians recommend masks for school kids, and how long does natural immunity last?

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  • This is becoming a “pandemic of the unvaccinated” according to the CDC’s Director - and the data prove it. Of the 130 people who died of COVID in Maryland in June, every single one of them was unvaccinated. (ABC)
  • While case counts are still much lower than they were in January on a national level, specific communities (with low vaccination rates) are being hit harder than ever before. (The Atlantic)
  • The CDC and State Department have issued a warning against travelling to the UK as cases skyrocket there. (Reuters)
  • Providing private vaccinations (so others don’t have to know you’re getting vaccinated) may be key to reaching some who are vaccine-resistant. (MedPage Today)
  • The largest organization representing pediatricians is recommending school-aged children (over the age of 2) wear masks indoors when returning to the classroom, due to concerns about outbreaks among unvaccinated children. This is in direct contrast to the CDC’s guidance which doesn’t require masks for school kids. (AAP)
  • The Olympics, set to start Friday, are already a COVID hotspot, with at least 4 athletes testing positive and many more cases among coaches and support staff. (USA Today)
  • Millions of doses of vaccine are set to go to waste as US states’ allocations near their expiration dates. (STAT)
  • Hollywood studios can mandate that everyone on set be vaccinated, after major unions voted on the subject this week. (New York Times)

Today’s Health News

  • Just when they’re lifting COVID restrictions, the UK is experiencing a large Norovirus outbreak. (Business Insider)
  • As if one pandemic wasn’t scary enough, the Colorado Department of Health (CDPHE) confirms that fleas with the plague were found in La Plata County. (DurangoHerald) 
  • Scientists have developed a way to use 3D printers to create synthetic grafts and repair ruptured ear drums under local anesthesia in just 20 minutes.  (StatNews)
  • The CDC confirmed a case of monkeypox, a rare but potentially dangerous virus, in a traveller returning to Texas from Nigeria. Luckily, COVID precautions like masks also limit monkeypox, another respiratory virus. (CDC)
  • A new study shows that even in the same hospitals, Black patients have worse outcomes than White patients - further evidence of the systemic racism in the US healthcare system. (LA Times)

Best Questions

With the Delta variant, how at risk are those who were previously COVID+ but aren’t vaccinated?

There isn't a lot of research out yet about this, because it's all so new, but early reports show that COVID antibodies from previous infection aren't as effective as vaccines in terms of protecting against the Delta variant. A new study in Nature shows that in 56 people who had COVID, their "natural" antibodies didn't protect very well against Delta, but after even just a single dose of Pfizer or Moderna, they neutralized all 4 strains of Delta variant. 

How long does natural immunity last? 

There isn't a lot of great data on the full length of natural immunity, or the immunity someone gets after they get sick with COVID. There is strong data showing that it lasts at least 90 days, and more recent studies showing it may last even longer, up to 8 or 9 months or more according to a recent NIH study. There's good evidence that those who were previously infected with COVID and vaccinated have very high protection levels after even just a single dose of mRNA vaccine. The CDC is still recommending they get a second dose just to be safe and to keep the recommendations consistent for everyone, but it does seem those with previous COVID infection and two doses of vaccine are basically the best protected people out there. It's important to note here that there was a recent study showing that for people who have never been infected with COVID before, it's crucial to get BOTH doses of vaccine for Pfizer and Moderna in terms of protecting against the Delta variant - one dose doesn't do much, but two works well against Delta and other variants.

Are hospitals seeing an uptick in admissions or severe disease in vaccinated people?

No - while breakthrough cases are happening, the vast majority are mild and don't require hospitalizations. The CDC has heard of about 5,500 total cases where someone vaccinated has gotten sick enough to require hospitalization, which is a tiny percentage of total cases - compare that to over 605,000 deaths and so many hospitalizations that the CDC can't even track that number. Most of those severe breakthrough cases are in people over age 65, and many have other comorbidities which may have added to the severity of their illness.  The vast majority of those in the hospital and dying of COVID now are unvaccinated. 

Are there any patterns to who is getting sick after being vaccinated in breakthrough cases?

Not really. Breakthrough cases are rare, but they do happen. There’s some evidence that the J&J vaccine is slightly less effective against mild to moderate illness, but all three vaccines approved in the US are extremely effective against severe disease. One thing to keep in mind is that there are over 337 million people vaccinated, so while breakthrough cases are rare, these numbers are so huge that even a tiny percentage of breakthrough cases is still a lot of people. If 95% of people vaccinated are totally prevented from getting COVID, that still leaves 5% - or 16.85 million people - who might get sick, though their illness will be much milder than if they weren’t vaccinated at all. And remember, the vaccines haven’t been administered evenly - nearly half of all vaccines given are Pfizer brand, because they were first and able to ramp up production sooner. So if you hear of a few Pfizer breakthrough cases, don’t assume that means Pfizer isn’t working, because it absolutely is. 

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Disclaimer: This post is meant for general information and educational purposes only and does not constitute, and is not intended as, any form of medical, legal or regulatory advice or a recommendation or suggestion regarding the same.  No recipient of this information should act or refrain from acting on the basis of this information without first seeking legal advice from counsel in the relevant jurisdiction.