Booster Update August 2021
Mel Herbert, MD
Vaccines in Immunocompromised data comes from a number of smallish studies
- About 2.7% of US population is considered immunocompromised - so we are talking 10 million people
- Anecdotal reports from ER’s across the country that immunosuppressed are getting sick with COVID
- One double blind trial on 120 organ transplant patients mean antibody, T cell and virus neutralization were significantly higher for those that got 3 doses of Moderna at 0,1,3 months compared to those that got 2
- 5 Cohort studies with a total of 112 patients noted seroconversion rates of only 33-50% with a 2 shot regime
- Admission data suggest a large % of vaccinated patients being admitted are the immunocompromised
- FDA now urges 3rd dose 28 days after the second
3rd Dose for Everyone
Joint statement by HHS Public Health and Medical Experts committee has suggested 3 doses for EVERYONE (currently ages > 12) 8 months after their last dose
- The statement doesn’t provide data
- Israel has given a 3rd dose to over 1 million people and reporting that with the 3rd dose receipts are 2.5 times more protected
- Israel HMA Maccabi reported the following: 149,144 people over 60 got a third dose
- Compared to 675,000 ish with just 2 doses
- A week later 37 infected in the 3 dose group 1064 in the 2 dose group
- 024% vs. 0.16% - 6 fold reduction
A large data set from Israel in pre-publication suggest that the chance of infection before and after 146 days - is higher the longer you where away from vaccination - but this was just infection not necessarily an important outcome itself
A CDC reported nursing home study also suggests warning immunity
- Cohort of nursing home patients followed before DELTA and after
- Suggested 74.7% reduction in infection pre-delta but only 53.1% post DELTA
- This could be from DELTA virulence and/or waning immunity
Note that these booster vaccinations are the SAME formulation as the original for now
MMWR reporting from New York
- May 3-July 25th
- Sustained excellent coverage from vaccination
- Possible slowly waning protection toward the end of this time frame, but was that the vaccine or other social factors like less masking and more interacting
Transmission post vaccine
Euro Surveill > 250,000 patients vaccine efficacy study to reduce transmission for close household contacts
- 71% - 75% reduction in getting the disease if vaccinated
- This was ALPHA variant
- Probably much higher with mRNA (this was a study of mostly non-mRNA vaccines)
- This is kind of the worst case scenario - lots of exposure and reexposure. Vaccines protect YOU and those around you
Natural Immunity not very good
MMWR Reinfection post vaccination - noted patients with prior infection and NO vaccination had significantly higher rate of reinfection than those vaccinated (2x) more likely
Medical Letter August 18th 2021
VG Hall et al. Randomized trial of a third dose of mRNA-1273 vaccine in transplant recipients. N Engl J Med 2021 August 11 (epub).
Shyam S. - August 20, 2021 11:06 AM
Does it matter on what type of Booster we get (Moderna vs Pfizer)--either benefits or downsides--based on what initial vaccination we recieved?
Joel R. - October 13, 2021 10:51 AM
Hopefully Co-ComV2 is published soon and we can figure that out
Mel H. - August 20, 2021 11:12 AM
I am sure they (CDC etc) will suggest get the version you already had BUT there is some emerging data that mix and matching is better AND that MODERNA is more protective than Pfizer for Delta variant. This is not yet peer reviewed so be careful, but here is a reference. https://www.medrxiv.org/content/10.1101/2021.08.06.21261707v2
Andrew J. - August 22, 2021 5:26 PM
If the NIH or somebody would've started enrollment for booster trials back in January, when millions of health care workers and SNF residents got second doses, then they could've given third doses to those folks in March, randomized them 1:1:1:1 to placebo, the same mRNA vaccine you got initially, the other mRNA vaccine, or J&J. Then in May those trial participants would've completed 2 months of follow-up, and we'd be going into this with some actual data on efficacy and safety. Hindsight is 20/20.
tom f. - August 23, 2021 12:34 AM
very fine rundown. thanks Mel and Swami
Michael M. - August 26, 2021 7:37 AM
Mel, did you say chance of being admitted for Covid if you are vaccinated is 0.06%, and chance of dying is 0.006%? Where did that data come from?
Mel H. - August 26, 2021 7:41 AM
It was from Israel. From a snapshot over a few weeks. Now CDC and LA county has better data. Shows the same basic idea. Vaccines reduce infection a lot but not 100% but prevention from death and ICU stay remains exceptional
Katie S. - August 26, 2021 7:55 AM
In the vein of covid news, there seems to be a renewed push at the state and national level for monoclonal antibody treatments for non-hospitalized patients. Initially there was a lot of skepticism about the evidence for mAb on EMA, but they are part of the current NIH treatment guidelines, I'd be interested to hear your experts opinions on whether these are worthwhile.
Ian L. - August 26, 2021 7:33 PM
Any more analysis on the Monoclonal antibodies for at risk patients as early as possible ?
Who is deciding on whether to initiate such treatment and any information on how many doses have been given ?
John V. - August 30, 2021 9:05 PM
I just want to take the mask off. How many jabs will I need?
E. F. B. - September 2, 2021 12:21 PM
I am feeling pressured to prescribe REGEN-COV (casirivimab 600 mg and imdevimab 600 mg) to minimally symptomatic Covid patients. What is the scoop on this regimen? I am reticent to add to the confusion and to recommend treatments that are unproven.